CAT.POL.A.100 Performance classes
Regulation (EU) No 965/2012
(a) The aeroplane shall be operated in accordance with the applicable performance class requirements.
(b) Where full compliance with the applicable requirements of this Section cannot be shown due to specific design characteristics, the operator shall apply approved performance standards that ensure a level of safety equivalent to that of the appropriate chapter.
Regulation (EU) 2019/1387
(a) The mass of the aeroplane:
(1) at the start of the take-off; or
(2) in the event of in-flight replanning, at the point from which the revised operational flight plan applies,
shall not be greater than the mass at which the requirements of the appropriate chapter can be complied with for the flight to be undertaken. Allowance may be made for expected reductions in mass as the flight proceeds and for fuel jettisoning.
(b) The approved performance data contained in the AFM shall be used to determine compliance with the requirements of the appropriate chapter, supplemented as necessary with other data as prescribed in the relevant chapter. The operator shall specify other data in the operations manual. When applying the factors prescribed in the appropriate chapter, account may be taken of any operational factors already incorporated in the AFM performance data to avoid double application of factors.
(c) Due account shall be taken of aeroplane configuration, environmental conditions and the operation of systems that have an adverse effect on performance.
(d) The operator shall take account of charting accuracy when assessing the take-off requirements of the applicable chapters.
CHAPTER 2 – Performance class A
Regulation (EU) No 965/2012
(a) The approved performance data in the AFM shall be supplemented as necessary with other data if the approved performance data in the AFM is insufficient in respect of items such as:
(1) accounting for reasonably expected adverse operating conditions such as take-off and landing on contaminated runways; and
(2) consideration of engine failure in all flight phases.
(b) For wet and contaminated runways, performance data determined in accordance with applicable standards on certification of large aeroplanes or equivalent shall be used.
(c) The use of other data referred to in (a) and equivalent requirements referred to in (b) shall be specified in the operations manual.
WET AND CONTAMINATED RUNWAY DATA
The determination of take-off performance data for wet and contaminated runways should be based on the reported runway surface condition in terms of contaminant and depth. The determination of landing performance data should be based on information provided in the OM on the reported RWYCC. The RWYCC is determined by the aerodrome operator using the RCAM and associated procedures defined in Annex V (Part-ADR.OPS) to Regulation (EU) No 139/2014. The RWYCC is reported through an RCR in the SNOWTAM format in accordance with ICAO Annex 15.
Regulation (EU) No 965/2012
(a) The take-off mass shall not exceed the maximum take-off mass specified in the AFM for the pressure altitude and the ambient temperature at the aerodrome of departure.
(b) The following requirements shall be met when determining the maximum permitted take-off mass:
(1) the accelerate-stop distance shall not exceed the accelerate-stop distance available (ASDA);
(2) the take-off distance shall not exceed the take-off distance available, with a clearway distance not exceeding half of the take-off run available (TORA);
(3) the take-off run shall not exceed the TORA;
(4) a single value of V1 shall be used for the rejected and continued take-off; and
(5) on a wet or contaminated runway, the take-off mass shall not exceed that permitted for a take-off on a dry runway under the same conditions.
(c) When showing compliance with (b), the following shall be taken into account:
(1) the pressure altitude at the aerodrome;
(2) the ambient temperature at the aerodrome;
(3) the runway surface condition and the type of runway surface;
(4) the runway slope in the direction of take-off;
(5) not more than 50 % of the reported headwind component or not less than 150 % of the reported tailwind component; and
(6) the loss, if any, of runway length due to alignment of the aeroplane prior to take-off.
LOSS OF RUNWAY LENGTH DUE TO ALIGNMENT
(a) The length of the runway that is declared for the calculation of take-off distance available (TODA), accelerate-stop distance available (ASDA) and take-off run available (TORA) does not account for line-up of the aeroplane in the direction of take-off on the runway in use. This alignment distance depends on the aeroplane geometry and access possibility to the runway in use. Accountability is usually required for a 90°-taxiway entry to the runway and 180°-turnaround on the runway. There are two distances to be considered:
(1) the minimum distance of the main wheels from the start of the runway for determining TODA and TORA,’L’; and
(2) the minimum distance of the most forward wheel(s) from the start of the runway for determining ASDA,’N’.
Figure 1
Line-up of the aeroplane in the direction of take-off — L and N
Where the aeroplane manufacturer does not provide the appropriate data, the calculation method given in (b) should be used to determine the alignment distance.
(b) Alignment distance calculation
The distances mentioned in (a)(1) and (a)(2) are:
|
|
90° entry |
180° turnaround |
|
L= |
RM + X |
RN + Y |
|
N= |
RM + X + WB |
RN + Y + WB |
where:
RN = A + WN = WB/cos(90°-α) + WN
RM = B + WM = WB tan(90°-α) + WM
X = safety distance of outer main wheel during turn to the edge of the runway
Y = safety distance of outer nose wheel during turn to the edge of the runway
Note: Minimum edge safety distances for X and Y are specified in FAA AC 150/5300-13 and ICAO Annex 14, 3.8.3
RN = radius of turn of outer nose wheel
RM = radius of turn of outer main wheel
WN = distance from aeroplane centre-line to outer nose wheel
WM = distance from aeroplane centre-line to outer main wheel
WB = wheel base
α = steering angle.
RUNWAY SURFACE CONDITION
(a) Operation on runways contaminated with water, slush, snow or ice implies uncertainties with regard to runway friction and contaminant drag and, therefore, to the achievable performance and control of the aeroplane during take-off, since the actual conditions may not completely match the assumptions on which the performance information is based. In the case of a contaminated runway, the first option for the commander is to wait until the runway is cleared. If this is impracticable, he/she may consider a take-off, provided that he/she has applied the applicable performance adjustments, and any further safety measures he/she considers justified under the prevailing conditions.
(b) An adequate overall level of safety will only be maintained if operations in accordance with AMC 25.1591 or equivalent are limited to rare occasions. Where the frequency of such operations on contaminated runways is not limited to rare occasions, the operator should provide additional measures ensuring an equivalent level of safety. Such measures could include special crew training, additional distance factoring and more restrictive wind limitations.
CAT.POL.A.210 Take-off obstacle clearance
Regulation (EU) No 965/2012
(a) The net take-off flight path shall be determined in such a way that the aeroplane clears all obstacles by a vertical distance of at least 35 ft or by a horizontal distance of at least 90 m plus 0,125 × D, where D is the horizontal distance the aeroplane has travelled from the end of the take-off distance available (TODA) or the end of the take-off distance if a turn is scheduled before the end of the TODA. For aeroplanes with a wingspan of less than 60 m, a horizontal obstacle clearance of half the aeroplane wingspan plus 60 m, plus 0,125 × D may be used.
(b) When showing compliance with (a):
(1) The following items shall be taken into account:
(i) the mass of the aeroplane at the commencement of the take-off run;
(ii) the pressure altitude at the aerodrome;
(iii) the ambient temperature at the aerodrome; and
(iv) not more than 50 % of the reported headwind component or not less than 150 % of the reported tailwind component.
(2) Track changes shall not be allowed up to the point at which the net take-off flight path has achieved a height equal to one half the wingspan but not less than 50 ft above the elevation of the end of the TORA. Thereafter, up to a height of 400 ft it is assumed that the aeroplane is banked by no more than 15°. Above 400 ft height bank angles greater than 15°, but not more than 25° may be scheduled.
(3) Any part of the net take-off flight path in which the aeroplane is banked by more than 15° shall clear all obstacles within the horizontal distances specified in (a), (b)(6) and (b)(7) by a vertical distance of at least 50 ft.
(4) Operations that apply increased bank angles of not more than 20° between 200 ft and 400 ft, or not more than 30° above 400 ft, shall be carried out in accordance with CAT.POL.A.240.
(5) Adequate allowance shall be made for the effect of bank angle on operating speeds and flight path including the distance increments resulting from increased operating speeds.
(6) For cases where the intended flight path does not require track changes of more than 15°, the operator does not need to consider those obstacles that have a lateral distance greater than:
(i) 300 m, if the pilot is able to maintain the required navigational accuracy through the obstacle accountability area; or
(ii) 600 m, for flights under all other conditions.
(7) For cases where the intended flight path requires track changes of more than 15°, the operator does not need to consider those obstacles that have a lateral distance greater than:
(i) 600 m, if the pilot is able to maintain the required navigational accuracy through the obstacle accountability area; or
(ii) 900 m, for flights under all other conditions.
(c) The operator shall establish contingency procedures to satisfy the requirements in (a) and (b) and to provide a safe route, avoiding obstacles, to enable the aeroplane to either comply with the en-route requirements of CAT.POL.A.215, or land at either the aerodrome of departure or at a take-off alternate aerodrome.
TAKE-OFF OBSTACLE CLEARANCE
(a) In accordance with the definitions used in preparing the take-off distance and take-off flight path data provided in the AFM:
(1) The net take-off flight path is considered to begin at a height of 35 ft above the runway or clearway at the end of the take-off distance determined for the aeroplane in accordance with (b) below.
(2) The take-off distance is the longest of the following distances:
(i) 115 % of the distance with all engines operating from the start of the take-off to the point at which the aeroplane is 35 ft above the runway or clearway;
(ii) the distance from the start of the take-off to the point at which the aeroplane is 35 ft above the runway or clearway assuming failure of the critical engine occurs at the point corresponding to the decision speed (V1) for a dry runway; or
(iii) if the runway is wet or contaminated, the distance from the start of the take-off to the point at which the aeroplane is 15 ft above the runway or clearway assuming failure of the critical engine occurs at the point corresponding to the decision speed (V1) for a wet or contaminated runway.
(b) The net take-off flight path, determined from the data provided in the AFM in accordance with (a)(1) and (a)(2), should clear all relevant obstacles by a vertical distance of 35 ft. When taking off on a wet or contaminated runway and an engine failure occurs at the point corresponding to the decision speed (V1) for a wet or contaminated runway, this implies that the aeroplane can initially be as much as 20 ft below the net take-off flight path in accordance with (a) and, therefore, may clear close-in obstacles by only 15 ft. When taking off on wet or contaminated runways, the operator should exercise special care with respect to obstacle assessment, especially if a take-off is obstacle-limited and the obstacle density is high.
EFFECT OF BANK ANGLES
(a) The AFM generally provides a climb gradient decrement for a 15° bank turn. For bank angles of less than 15°, a proportionate amount should be applied unless the manufacturer or AFM has provided other data.
(b) Unless otherwise specified in the AFM or other performance or operating manuals from the manufacturer, acceptable adjustments to assure adequate stall margins and gradient corrections are provided by the following table:
Table 1
Effect of bank angles
|
Bank |
Speed |
Gradient correction |
|
15° |
V2 |
1 x AFM 15° gradient loss |
|
20° |
V2 + 5 kt |
2 x AFM 15° gradient loss |
|
25° |
V2 + 10 kt |
3 x AFM 15° gradient loss |
REQUIRED NAVIGATIONAL ACCURACY
(a) Navigation systems
The obstacle accountability semi-widths of 300 m and 600 m may be used if the navigation system under OEI conditions provides a two standard deviation accuracy of 150 m and 300 m respectively.
(b) Visual course guidance
(1) The obstacle accountability semi-widths of 300 m and 600 m may be used where navigational accuracy is ensured at all relevant points on the flight path by use of external references. These references may be considered visible from the flight crew compartment if they are situated more than 45° either side of the intended track and with a depression of not greater than 20° from the horizontal.
(2) For visual course guidance navigation, the operator should ensure that the weather conditions prevailing at the time of operation, including ceiling and visibility, are such that the obstacle and/or ground reference points can be seen and identified. The operations manual should specify, for the aerodrome(s) concerned, the minimum weather conditions which enable the flight crew to continuously determine and maintain the correct flight path with respect to ground reference points, so as to provide a safe clearance with respect to obstructions and terrain as follows:
(i) the procedure should be well-defined with respect to ground reference points so that the track to be flown can be analysed for obstacle clearance requirements;
(ii) the procedure should be within the capabilities of the aeroplane with respect to forward speed, bank angle and wind effects;
(iii) a written and/or pictorial description of the procedure should be provided for crew use; and
(iv) the limiting environmental conditions (such as wind, the lowest cloud base, ceiling, visibility, day/night, ambient lighting, obstruction lighting) should be specified.
CONTINGENCY PROCEDURES FOR OBSTACLES CLEARANCES
If compliance with CAT.POL.A.210 is based on an engine failure route that differs from the all engine departure route or SID normal departure, a ‘deviation point’ can be identified where the engine failure route deviates from the normal departure route. Adequate obstacle clearance along the normal departure route with failure of the critical engine at the deviation point will normally be available. However, in certain situations the obstacle clearance along the normal departure route may be marginal and should be checked to ensure that, in case of an engine failure after the deviation point, a flight can safely proceed along the normal departure route.
CAT.POL.A.215 En-route – one-engine-inoperative (OEI)
Regulation (EU) 2023/217
(a) The OEI en-route net flight path data shown in the AFM, appropriate to the meteorological conditions expected for the flight, shall allow demonstration of compliance with (b) or (c) at all points along the route. The net flight path shall have a positive gradient at 1 500 ft above the aerodrome where the landing is assumed to be made after engine failure. In meteorological conditions requiring the operation of ice protection systems, the effect of their use on the net flight path shall be taken into account.
(b) The gradient of the en-route net flight path shall be positive at least 1 000 ft above all terrain and obstructions along the route within 9,3 km (5 NM) on either side of the intended track.
(c) The en-route net flight path shall permit the aeroplane to continue flight from the cruising altitude to an aerodrome where a landing can be made in accordance with point CAT.POL.A.230 or CAT.POL.A.235, as appropriate. The en-route net flight path shall clear vertically, by at least 2 000 ft, all terrain and obstructions along the route within 9,3 km (5 NM) on either side of the intended track, taking into account the following elements:
(1) the engine is assumed to fail at the most critical point along the route;
(2) account is taken of the effects of winds on the flight path;
(3) fuel jettisoning is permitted to an extent consistent with reaching the aerodrome where the aeroplane is assumed to land after engine failure with the required fuel reserves in accordance with point CAT.OP.MPA.181, appropriate for an alternate aerodrome, if a safe procedure is used;
(4) the aerodrome, where the aeroplane is assumed to land after engine failure, shall meet the following criteria:
(i) the performance requirements for the expected landing mass are met;
(ii) weather reports or forecasts and runway condition reports indicate that a safe landing can be accomplished at the estimated time of landing;
(5) if the AFM does not contain en-route net flight path data, the gross OEI en-route flight path shall be reduced by a climb gradient of 1,1 % for two-engined aeroplanes, 1,4 % for three-engined aeroplanes, and 1,6 % for four-engined aeroplanes.
(d) The operator shall increase the width margins provided for in points (b) and (c) to 18,5 km (10 NM) if the navigational accuracy does not meet at least navigation specification RNAV 5.
ROUTE ANALYSIS
(a) The high terrain or obstacle analysis required should be carried out by a detailed analysis of the route.
(b) A detailed analysis of the route should be made using contour maps of the high terrain and plotting the highest points within the prescribed corridor’s width along the route. The next step is to determine whether it is possible to maintain level flight with OEI 1 000 ft above the highest point of the crossing. If this is not possible, or if the associated weight penalties are unacceptable, a drift down procedure should be worked out, based on engine failure at the most critical point and clearing critical obstacles during the drift down by at least 2 000 ft. The minimum cruise altitude is determined by the intersection of the two drift down paths, taking into account allowances for decision making (see Figure 1). This method is time-consuming and requires the availability of detailed terrain maps.
(c) Alternatively, the published minimum flight altitudes (MEA or minimum off-route altitude (MORA)) should be used for determining whether OEI level flight is feasible at the minimum flight altitude, or if it is necessary to use the published minimum flight altitudes as the basis for the drift down construction (see Figure 1). This procedure avoids a detailed high terrain contour analysis, but could be more penalising than taking the actual terrain profile into account as in (b).
(d) In order to comply with CAT.POL.A.215 (c), one means of compliance is the use of MORA and, with CAT.POL.A.215 (d), MEA provided that the aeroplane meets the navigational equipment standard assumed in the definition of MEA.
Figure 1
Intersection of the two drift down paths
Note: MEA or MORA normally provide the required 2 000 ft obstacle clearance for drift down. However, at and below 6 000 ft altitude, MEA and MORA cannot be used directly as only 1 000 ft clearance is ensured.
CAT.POL.A.220 En-route – aeroplanes with three or more engines, two engines inoperative
Regulation (EU) 2021/1296
(a) An aeroplane that has three or more engines shall not be away from an aerodrome at which the requirements of points CAT.POL.A.230 or CAT.POL.A.235(a) for the expected landing mass are met accordingly, at any point along the intended track for more than 90 minutes, with all engines operating at cruising power or thrust, as appropriate, at standard temperature in still air, unless points (b) to (f) of this point are complied with.
(b) The two-engines-inoperative en-route net flight path data shall allow the aeroplane to continue the flight, in the expected meteorological conditions, from the point where two engines are assumed to fail simultaneously to an aerodrome at which it is possible to land and come to a complete stop when using the prescribed procedure for a landing with two engines inoperative. The en-route net flight path shall clear vertically, by at least 2 000 ft, all terrain and obstructions along the route within 9,3 km (5 NM) on either side of the intended track. At altitudes and in meteorological conditions that require ice protection systems to be operable, the effect of their use on the en-route net flight path data shall be taken into account. If the navigational accuracy does not meet at least navigation specification RNAV 5, the operator shall increase the prescribed width margin provided for in the second sentence to 18,5 km (10 NM).
(c) The two engines shall be assumed to fail at the most critical point of that portion of the route where the aeroplane is operated for more than 90 minutes, with all engines operating at cruising power or thrust, as appropriate, at standard temperature in still air, away from the aerodrome referred to in point (a).
(d) The net flight path shall have a positive gradient at 1 500 ft above the aerodrome where the landing is assumed to be made after the failure of two engines.
(e) Fuel jettisoning shall be permitted to an extent consistent with reaching the aerodrome with the required fuel reserves referred to in point (f), if a safe procedure is used.
(f) The expected mass of the aeroplane at the point where the two engines are assumed to fail shall not be less than that which would include sufficient fuel/energy to proceed to an aerodrome where the landing is assumed to be made, and to arrive there at an altitude of at least 1 500 ft (450 m) directly over the landing area, and thereafter, to fly for 15 minutes at cruising power or thrust, as appropriate.
CAT.POL.A.225 Landing – destination and alternate aerodromes
Regulation (EU) No 965/2012
(a) The landing mass of the aeroplane determined in accordance with CAT.POL.A.105(a) shall not exceed the maximum landing mass specified for the altitude and the ambient temperature expected for the estimated time of landing at the destination aerodrome and alternate aerodrome.
ALTITUDE MEASURING
The operator should use either pressure altitude or geometric altitude for its operation and this should be reflected in the operations manual.
MISSED APPROACH
(a) For instrument approaches with a missed approach climb gradient greater than 2.5 %, the operator should verify that the expected landing mass of the aeroplane allows for a missed approach with a climb gradient equal to or greater than the applicable missed approach gradient in the OEI missed approach configuration and at the associated speed.
(b) For instrument approaches with DH below 200 ft, the operator should verify that the expected landing mass of the aeroplane allows a missed approach gradient of climb, with the critical engine failed and with the speed and configuration used for a missed approach of at least 2.5 %, or the published gradient, whichever is greater.
MISSED APPROACH GRADIENT
(a) Where an aeroplane cannot achieve the missed approach gradient specified in AMC2 CAT.POL.A.225, when operating at or near maximum certificated landing mass and in engine-out conditions, the operator has the opportunity to propose an alternative means of compliance to the competent authority demonstrating that a missed approach can be executed safely taking into account appropriate mitigating measures.
(b) The proposal for an alternative means of compliance may involve the following:
(1) considerations to mass, altitude and temperature limitations and wind for the missed approach;
(2) a proposal to increase the DA/H or MDA/H; and
(3) a contingency procedure ensuring a safe route and avoiding obstacles.
CAT.POL.A.230 Landing – dry runways
Regulation (EU) 2023/217
(a) The landing mass of the aeroplane determined in accordance with point CAT.POL.A.105(a) for the estimated time of landing at the destination aerodrome and at any alternate aerodrome shall allow a full-stop landing from 50 ft above the threshold:
(1) for turbojet-powered aeroplanes, within 60 % of the landing distance available (LDA);
(2) for turbopropeller-powered aeroplanes, within 70 % of the LDA;
(3) by way of derogation from points (a)(1) and (a)(2), for aeroplanes that are approved for reduced landing distance operations under point CAT.POL.A.255, within 80 % of the LDA.
(b) For steep approach operations, the operator shall use the landing distance data factored in accordance with point (a)(1) or (a)(2), as applicable, based on a screen height of less than 60 ft, but not less than 35 ft, and shall comply with point CAT.POL.A.245.
(c) For short landing operations, the operator shall use the landing distance data factored in accordance with point (a)(1) or (a)(2), as applicable, and shall comply with point CAT.POL.A.250.
(d) When determining the landing mass, the operator shall take into account the following:
(1) not more than 50 % of the headwind component or not less than 150 % of the tailwind component;
(2) corrections as provided in the AFM.
(e) For dispatching the aeroplane, the aeroplane shall:
(1) land on the most favourable runway, in still air; and
(2) land on the runway most likely to be assigned, considering the probable wind speed and direction, the ground-handling characteristics of the aeroplane and other conditions such as landing aids and terrain.
(f) If the operator is unable to comply with point (e)(2) for the destination aerodrome, the aeroplane shall only be dispatched if an alternate aerodrome is designated that allows full compliance with one of the following:
(1) points (a) to (d), if the runway at the estimated time of arrival is dry;
(2) points CAT.POL.A.235(a) to (d), if the runway at the estimated time of arrival is wet or contaminated.
AMC1 CAT.POL.A.230 Landing — dry runways
ED Decision 2022/012/R
FACTORING OF AUTOMATIC LANDING DISTANCE PERFORMANCE DATA
In those cases where the landing requires the use of an automatic landing system, and the distance published in the AFM includes safety margins equivalent to those contained in CAT.POL.A.230(a)(1) and CAT.POL.A.230(a)(2), the landing mass of the aeroplane should be the lesser of:
(a) the landing mass determined in accordance with CAT.POL.A.230(a)(1) and CAT.POL.A.230(a)(2); or
(b) the landing mass determined for the automatic landing distance for the appropriate surface condition, as given in the AFM or equivalent document. Increments due to system features such as beam location or elevations, or procedures such as use of overspeed, should also be included.
AMC2 CAT.POL.A.230 Landing — dry runways
ED Decision 2022/012/R
FACTORING OF LANDING DISTANCE PERFORMANCE DATA WHEN USING A HEAD-UP DISPLAY (HUD) OR AN EQUIVALENT DISPLAY WITH FLARE CUE
In those cases where the landing requires the use of a HUD or an equivalent display with flare cue, and the landing distance published in the AFM includes safety factors, the landing mass of the aeroplane should be the lesser of:
(a) the landing mass determined in accordance with CAT.POL.A.230(a)(1); or
(b) the landing mass determined, when using a HUD or an equivalent display with flare cue for the appropriate surface condition, as given in the AFM or equivalent document.
LANDING MASS
CAT.POL.A.230 establishes two considerations in determining the maximum permissible landing mass at the destination and alternate aerodromes:
(a) Firstly, the aeroplane mass will be such that on arrival the aeroplane can be landed within 60 %, 70 %, or 80 % (as applicable) of the landing distance available (LDA) on the most favourable (normally the longest) runway in still air. Regardless of the wind conditions, the maximum landing mass for an aerodrome/aeroplane configuration at a particular aerodrome cannot be exceeded.
(b) Secondly, consideration should be given to anticipated conditions and circumstances. The expected wind, or ATC and noise abatement procedures, may indicate the use of a different runway. These factors may result in a lower landing mass than that permitted under (a), in which case dispatch should be based on this lesser mass.
(c) The expected wind referred to in (b) is the wind expected to exist at the time of arrival.
GM1 CAT.POL.A.230 & CAT.POL.A.235 Landing — dry runways & Landing — wet and contaminated runways
ED Decision 2021/005/R
WORKFLOW OF THE LANDING DISTANCE ASSESSMENT AT THE TIME OF DISPATCH — RUNWAY SUITABILITY CHECK
WORKFLOW OF THE LANDING DISTANCE ASSESSMENT AT THE TIME OF DISPATCH — DRY RUNWAYS
WORKFLOW OF THE LANDING DISTANCE ASSESSMENT AT THE TIME OF DISPATCH — WET RUNWAYS
WORKFLOW OF THE LANDING DISTANCE ASSESSMENT AT THE TIME OF DISPATCH — CONTAMINATED RUNWAYS
GM2 CAT.POL.A.230 & CAT.POL.A.235 Landing — dry runways & Landing — wet and contaminated runways
ED Decision 2021/005/R
LANDING DISTANCES AND CORRECTIVE FACTORS
The AFM provides performance data for landing distance under conditions defined in the applicable certification standards. This distance, commonly referred to as the actual landing distance (ALD), is the distance from the position on the runway of the screen height to the point where the aeroplane comes to a full stop on a dry runway.
The determination of the ALD is based on the assumption that the landing is performed in accordance with the conditions and the procedures set out in the AFM on the basis of the applicable certification standards.
As a matter of fact, any particular landing may be different from the landing technique that is assumed in the AFM for certification purposes. The aircraft may approach the runway faster and/or higher than assumed; the aircraft may touch down further along the runway than the optimum point; the actual winds and other weather factors may be different from those assumed in the calculation of the ALD; and maximum braking may not be always achievable. For this reason, the LDA is required by CAT.POL.A.230 and CAT.POL.A.235 to be longer than the ALD.
The margins by which the LDA shall exceed the ALD on dry runways, in accordance with CAT.POL.A.230, are shown in the following Table 1.
Table 1: Corrective factors for dry runways
|
Aeroplane category |
Required margin (dry runway) |
Resulting factor (dry runway) |
|
Turbojet-powered aeroplanes |
ALD < 60 % of the LDA |
LDA = at least 1.67 x ALD |
|
Turbopropeller-powered aeroplanes |
ALD < 70 % of the LDA |
LDA = at least 1.43 x ALD |
|
Aeroplanes approved under CAT.POL.A.255 |
ALD < 80 % of the LDA |
LDA = at least 1.25 x ALD |
If the runway is wet and the AFM does not provide specific performance data for dispatch on wet runways, a further increase of 15 % of the landing distance on dry runways has to be applied, in accordance with CAT.POL.A.235, as shown in the following Table 2.
Table 2: Corrective factors for wet runways
|
Aeroplane category |
Resulting factor (dry runway) |
|
Turbojet-powered aeroplanes |
LDA = at least 1.15 x 1.67 x ALD = 1.92 x ALD |
|
Turbopropeller-powered aeroplanes |
LDA = at least 1.15 x 1.43 x ALD = 1.64 x ALD |
|
Aeroplanes approved under CAT.POL.A.255 |
LDA = at least 1.15 x 1.25 X ALD = 1.44 x ALD |
However, for aeroplanes that are approved under CAT.POL.A.255, when landing on wet runways, CAT.POL.A.255 further requires the flight crew to apply the longer of the landing distance resulting from the above table and the landing distance resulting from the application of CAT.OP.MPA.303(a) or (b) as applicable. If performance information for the assessment of LDTA is not available as per CAT.OP.MPA.303(b)(2), the required landing distance on wet runways should be at least: 1.15 x 1.67 x ALD for turbojet-powered aircraft and 1.15 x 1.43 x ALD for turbopropeller-powered aircraft.
GM1 CAT.POL.A.230(a) Landing — dry runways
ED Decision 2021/005/R
ALTERNATE AERODROMES
The alternate aerodromes for which the landing mass is required to be determined in accordance with CAT.POL.A.230 are:
(a) destination alternate aerodromes;
(b) fuel ERA aerodromes; and
(c) re-dispatch or re-clearance aerodromes.
GM1 CAT.POL.A.230(d)(2) Landing — dry runways
ED Decision 2021/005/R
AFM LANDING PERFORMANCE CORRECTIONS
Landing performance data is provided in the AFM at least for the certified range of pressure altitudes. AFM data may include other influence parameters such as, but not limited to, runway slope and temperature. The effect of speed increments over threshold should also be accounted for when these increments are required by the applicable AFM procedures, such as autoland or steep approach.
CAT.POL.A.235 Landing – wet and contaminated runways
Regulation (EU) 2023/217
(a) When the appropriate weather reports or forecasts, or both, indicate that the runway at the estimated time of arrival may be wet, the LDA shall be one of the following distances:
(1) a landing distance provided in the AFM for use on wet runways at time of dispatch, but not less than that required by point CAT.POL.A.230(a)(1) or (a)(2), as applicable;
(2) if a landing distance is not provided in the AFM for use on wet runways at time of dispatch, at least 115 % of the required landing distance, determined in accordance with point CAT.POL.A.230(a)(1) or (a)(2), as applicable;
(3) a landing distance shorter than that required by point (a)(2), but not less than that required by point CAT.POL.A.230(a)(1) or (a)(2), as applicable, if the runway has specific friction-improving characteristics and the AFM includes specific additional information for landing distance on that runway type;
(4) by way of derogation from points (a)(1), (a)(2) and (a)(3), for aeroplanes that are approved for reduced landing distance operations under point CAT.POL.A.255, the landing distance determined in accordance with point CAT.POL.A.255(b)(2)(v)(B).
(b) When the appropriate weather reports or forecasts indicate that the runway at the estimated time of arrival may be contaminated, the LDA shall be one of the following distances:
(1) at least the landing distance determined in accordance with point (a), or at least 115 % of the landing distance determined in accordance with approved contaminated landing distance data or equivalent, whichever is greater;
(2) on specially prepared winter runways, a landing distance shorter than that required by point (b)(1), but not less than that required by point (a), may be used if the AFM includes specific additional information about landing distances on contaminated runways. Such landing distance shall be at least 115 % of the landing distance contained in the AFM.
(c) By way of derogation from point (b), the increment of 15 % needs not to be applied if it is already included in the approved landing distance data or equivalent.
(d) For points (a) and (b), the criteria of points CAT.POL.A.230(b), (c) and (d) shall apply accordingly.
(e) For dispatching the aeroplane, the aeroplane shall:
(1) land on the most favourable runway, in still air; and
(2) land on the runway most likely to be assigned, considering the probable wind speed and direction, the ground-handling characteristics of the aeroplane and other conditions such as landing aids and terrain.
(f) If the operator is unable to comply with point (e)(1) for a destination aerodrome where the appropriate weather reports or forecasts indicate that the runway at the estimated time of arrival may be contaminated and where a landing depends upon a specific wind component, the aeroplane shall only be dispatched if two alternate aerodromes are designated.
(g) If the operator is unable to comply with point (e)(2) for the destination aerodrome where the appropriate weather reports or forecasts indicate that the runway at the estimated time of arrival may be wet or contaminated, the aeroplane shall only be dispatched if an alternate aerodrome is designated.
(h) For points (f) and (g), the designated alternate aerodrome or aerodromes shall allow compliance with one of the following:
(1) points CAT.POL.A.230(a) to (d), if the runway at the estimated time of arrival is dry;
(2) points CAT.POL.A.235(a) to (d), if the runway at the estimated time of arrival is wet or contaminated.
AMC1 CAT.POL.A.235 Landing — dry runways
ED Decision 2022/012/R
FACTORING OF AUTOMATIC LANDING DISTANCE PERFORMANCE DATA
In those cases where the landing requires the use of an automatic landing system, and the distance published in the AFM includes safety margins equivalent to thse contained in CAT.POL.A.235, the landing mass of the aeroplane should be the lesser of:
(a) the landing mass determined in accordance with CAT.POL.A.235; or
(b) the landing mass determined for the automatic landing distance for the appropriate surface condition, as given in the AFM or equivalent document. Increments due to system features such as beam location or elevations, or procedures such as use of overspeed, should also be included.
AMC2 CAT.POL.A.235 Landing — wet and contaminated runways
ED Decision 2023/007/R
FACTORING OF LANDING DISTANCE PERFORMANCE DATA WHEN USING A HEAD-UP DISPLAY (HUD) OR AN EQUIVALENT DISPLAY WITH FLARE CUE
In those cases where the landing requires the use of a HUD or an equivalent display with flare cue, and the landing distance published in the AFM includes safety factors, the landing mass of the aeroplane should be the lesser of:
(a) the landing mass determined in accordance with CAT.POL.A.235; or
(b) the landing mass determined, when using a HUD or an equivalent display with flare cue for the appropriate surface condition, as given in the AFM or equivalent document.
GM1 CAT.POL.A.235(a) and (b) Landing — wet and contaminated runways
ED Decision 2021/005/R
DISPATCH CONSIDERATIONS FOR MARGINAL CASES
The LDTA required by CAT.OP.MPA.303 may, in some cases, and in particular on wet or contaminated runways, exceed the landing distance considered at the time of dispatch. The requirements for dispatch remain unchanged, however, when the conditions at the time of arrival are expected to be marginal, it is a good practice to carry out at the time of dispatch a preliminary calculation of the LDTA.
GM1 CAT.POL.A.235(a)(1) Landing — wet and contaminated runways
ED Decision 2021/005/R
AFM LANDING DISTANCES FOR WET RUNWAYS
Specific landing distances provided in the AFM for dispatch on wet runways, unless otherwise indicated, include a safety factor, which renders not necessary the application of the 15 % safety factor used in CAT.POL.A.235(a)(2). This implies that the AFM distance may be presented as factored distance. When the AFM distance is not factored, a safety factor of 15 % should be applied. These distances may be longer or shorter than those resulting from CAT.POL.A.235(a)(2), but when provided, they are intended as a replacement of CAT.POL.A.235(a)(2) and mandatory for use at the time of dispatch.
AMC1 CAT.POL.A.235(a)(3) Landing — wet and contaminated runways
ED Decision 2021/005/R
RUNWAYS WITH FRICTION IMPROVING CHARACTERISTICS
Materials or construction techniques meant to improve the friction characteristics of a runway may be grooved runways, runways treated with porous friction course (PFC) or other materials or techniques for which the AFM provides specific performance data.
Before taking the AFM performance credit for such runways, the operator should verify that the runways intended to be operated on are maintained to the extent necessary to ensure the expected improved friction characteristics.
CAT.POL.A.240 Approval of operations with increased bank angles
Regulation (EU) No 379/2014
(a) Operations with increased bank angles require prior approval by the competent authority.
(b) To obtain the approval, the operator shall provide evidence that the following conditions are met:
(1) the AFM contains approved data for the required increase of operating speed and data to allow the construction of the flight path considering the increased bank angles and speeds;
(2) visual guidance is available for navigation accuracy;
(3) weather minima and wind limitations are specified for each runway; and
(4) the flight crew has obtained adequate knowledge of the route to be flown and of the procedures to be used in accordance with Subpart FC of Part-ORO.
CAT.POL.A.245 Approval of steep approach operations
Regulation (EU) No 965/2012
(a) Steep approach operations using glideslope angles of 4,5° or more and with screen heights of less than 60 ft, but not less than 35 ft, require prior approval by the competent authority.
(b) To obtain the approval, the operator shall provide evidence that the following conditions are met:
(1) the AFM states the maximum approved glideslope angle, any other limitations, normal, abnormal or emergency procedures for the steep approach as well as amendments to the field length data when using steep approach criteria;
(2) for each aerodrome at which steep approach operations are to be conducted:
(i) a suitable glide path reference system comprising at least a visual glide path indicating system shall be available;
(ii) weather minima shall be specified; and
(iii) the following items shall be taken into consideration:
(A) the obstacle situation;
(B) the type of glide path reference and runway guidance;
(C) the minimum visual reference to be required at decision height (DH) and MDA;
(D) available airborne equipment;
(E) pilot qualification and special aerodrome familiarisation;
(F) AFM limitations and procedures; and
(G) missed approach criteria.
GM1 CAT.POL.A.245(a) Approval of steep approach operations
ED Decision 2021/005/R
SCREEN HEIGHT
For the purpose of steep approach operations, the screen height is the reference height above the runway surface, typically above the runway threshold, from which the landing distance is measured. The screen height is set at 50 ft for normal operations and at another value between 60 ft and 35 ft for steep approach operations.
CAT.POL.A.250 Approval of short landing operations
Regulation (EU) 2019/1387
(a) Short landing operations require prior approval by the competent authority.
(b) To obtain the approval, the operator shall provide evidence that the following conditions are met:
(1) the distance used for the calculation of the permitted landing mass may consist of the usable length of the declared safe area plus the declared LDA;
(2) the State of the aerodrome has determined a public interest and operational necessity for the operation, either due to the remoteness of the aerodrome or to physical limitations relating to extending the runway;
(3) the vertical distance between the path of the pilot’s eye and the path of the lowest part of the wheels, with the aeroplane established on the normal glide path, does not exceed 3 m;
(4) RVR/VIS minimum shall not be less than 1 500 m and wind limitations are specified in the operations manual;
(5) minimum pilot experience, training and special aerodrome familiarisation requirements are specified and met;
(6) the crossing height over the beginning of the usable length of the declared safe area is 50 ft;
(7) the use of the declared safe area is approved by the State of the aerodrome;
(8) the usable length of the declared safe area does not exceed 90 m;
(9) the width of the declared safe area is not less than twice the runway width or twice the wing span, whichever is greater, centred on the extended runway centre line;
(10) the declared safe area is clear of obstructions or depressions that would endanger an aeroplane undershooting the runway and no mobile object is permitted on the declared safe area while the runway is being used for short landing operations;
(11) the slope of the declared safe area does not exceed 5 % upward nor 2 % downward in the direction of landing;
(11a) reduced required landing distance operations in accordance with CAT.POL.A.255 are prohibited; and
(12) additional conditions, if specified by the competent authority, taking into account aeroplane type characteristics, orographic characteristics in the approach area, available approach aids and missed approach/balked landing considerations.
CAT.POL.A.255 Approval of reduced required landing distance operations
Regulation (EU) 2020/1176
(a) An aeroplane operator may conduct landing operations within 80 % of the landing distance available (LDA) if it complies with the following conditions:
(1) the airplane has an MOPSC of 19 or less;
(2) the airplane has an eligibility statement for reduced required landing distance in the AFM;
(3) the airplane is used in non-scheduled on-demand commercial air transport (CAT) operations;
(4) the landing mass of the aeroplane allows a full-stop landing within that reduced landing distance;
(5) the operator has obtained a prior approval of the competent authority.
(b) To obtain the approval referred to in point (a)(5), the operator shall provide evidence of either of the following circumstances:
(1) that a risk assessment has been conducted to demonstrate that a level of safety equivalent to that intended by point CAT.POL.A.230(a)(1) or (2), as applicable, is achieved;
(2) that the following conditions are met:
(i) special-approach procedures, such as steep approaches, planned screen heights higher than 60 ft or lower than 35 ft, low-visibility operations, approaches outside stabilised approach criteria approved under point CAT.OP.MPA.115(a), are prohibited;
(ii) short landing operations in accordance with point CAT.POL.A.250 are prohibited;
(iii) landing on contaminated runways is prohibited;
(iv) an adequate training, checking and monitoring process for the flight crew is established;
(v) an aerodrome landing analysis programme (ALAP) is established by the operator to ensure that the following conditions are met:
(A) no tailwind is forecast at the expected time of arrival;
(B) if the runway is forecast to be wet at the expected time of arrival, the landing distance at dispatch shall either be determined in accordance with point CAT.OP.MPA.303(a) or (b) as applicable, or shall be 115 % of the landing distance determined for dry runways, whichever is longer;
(C) no forecast contaminated runway conditions exist at the expected time of arrival;
(D) no forecast adverse weather conditions exist at the expected time of arrival;
(vi) all the equipment that affects landing performance is operative before commencing the flight;
(vii) the flight crew is composed of at least two qualified and trained pilots that have recency in reduced required landing distance operations;
(viii) based on the prevailing conditions for the intended flight, the commander shall make the final decision to conduct reduced required landing distance operations and may decide not to do so when he or she considers that to be in the interest of safety;
(ix) additional aerodrome conditions, if specified by the competent authority that has certified the aerodrome, taking into account orographic characteristics of the approach area, available approach aids, missed-approach and balked-landing considerations.
GM1 CAT.POL.A.255(a)(2) Approval of reduced required landing distance operations
ED Decision 2021/005/R
AEROPLANE ELIGIBILITY
The factors required by CAT.POL.A.230(a)(1) or (a)(2), as applicable, provide an operational safety margin to take into account landing distance operational variability in normal operations compared to the conditions and procedures set out to determine the actual landing distances during the certification of the aeroplane. The reduction of this margin, allowed when operating with reduced required landing distance, is based on a set of mitigating conditions required by CAT.POL.A.255.
However, if the factors required by CAT.POL.A.230(a)(1) or (a)(2), as applicable, have been used during the certification of the aeroplane to demonstrate compliance with certification standards such as, but not limited to, CS 25.1309 or equivalent, the aeroplane is not eligible for a reduction of the margin provided by those factors.
Furthermore, certification methods offer different options for the determination of the air distance portion of the landing distance in terms of assumption that can be made for parameters such as, but not limited to, glide path angle and sink rate at touchdown. The assumptions made during the certification of the aeroplane may increase the landing distance operational variability in normal operations. The effect of parameters such as temperature or runway slope, when these were not considered during certification, may as well increase the landing distances achievable in normal operations. Overall, the set of assumptions made during the certification of the aeroplane may not be always compatible with the operational safety margin reduction allowed in reduced required landing distance operations under CAT.POL.A.255.
Whether the factors required by CAT.POL.A.230(a)(1) or (a)(2), as applicable, have been used to demonstrate compliance with certification standards, or the set of assumptions made to determine actual landing distances during the certification of the aeroplane are compatible with reduced landing distance operations, may be only declared by the aeroplane manufacturer or by the TC/STC holder.
GM1 CAT.POL.A.255(a)(3) Approval of reduced required landing distance operations
ED Decision 2021/005/R
NON-SCHEDULED ON-DEMAND COMMERCIAL AIR TRANSPORT (CAT) OPERATIONS
For the purpose of reduced required landing distance operations, non-scheduled on-demand CAT operations are those CAT operations conducted upon request of the customer.
Non-scheduled on-demand CAT operations eligible for reduced required landing distance operations do not include holiday charters, i.e. charter flights that are part of a holiday travel package.
AMC1 CAT.POL.A.255(b)(1) Approval of reduced required landing distance operations
ED Decision 2021/005/R
EQUIVALENT LEVEL OF SAFETY
A level of safety equivalent to that intended by CAT.POL.A.230(a)(1) or CAT.POL.A.230(a)(2), as applicable, may be achieved when conducting reduced required landing distance operations if mitigating measures are established and implemented. Such measures should address flight crew, aircraft characteristics and performance, aerodromes and operations. It is, however, essential that all conditions established are adhered to as it is the combination of said conditions that achieves the intended level of safety. The operator should in fact also consider the interrelation of the various mitigating measures.
The mitigating measures may be determined by the operator by using a risk assessment or by fulfilling all the conditions established under CAT.POL.A.255(b)(2). An operator willing to establish a set of conditions different from those under CAT.POL.A.255(b)(2) needs to demonstrate to the competent authority the equivalent level of safety through a risk assessment.
The risk assessment required by CAT.POL.A.255(b)(1) should include at least the following elements:
(a) flight crew qualification in terms of training, checking and recency;
(b) flight crew composition;
(c) runway surface conditions;
(d) dispatch criteria;
(e) weather conditions and limitations, including crosswind;
(f) aerodrome characteristics, including available approach guidance;
(g) aeroplane characteristics and limitations;
(h) aeroplane equipment and systems affecting landing performance;
(i) aeroplane performance data;
(j) operating procedures and operating minima; and
(k) analysis of operators’s performance and occurrence reports related to unstable approaches and long landings.
The competent authority may require other mitigating measures in addition to those proposed by the operator.
AMC1 CAT.POL.A.255(b)(2)(iv) Approval of reduced required landing distance operations
ED Decision 2021/005/R
GENERAL
(a) The operator should ensure that flight crew training programmes for reduced required landing distance operations include ground training, flight simulation training device (FSTD), and/or flight training.
(b) Flight crew with no reduced required landing distance operations experience should have completed the full training programme of (a) above.
(c) Flight crew with previous reduced required landing distance operations experience of a similar type of operation with another EU operator, may undertake the following:
(1) an abbreviated ground training course if operating an aircraft of a type or class different from that of the aircraft on which the previous reduced required landing distance operations experience was gained;
(2) an abbreviated ground, FSTD and/or flight training course if operating the same type or class and variant of the same aircraft type or class on which the previous reduced required landing distance operations experience was gained; this course should include at least the provisions of the conversion training contained in this AMC; the operator may reduce the number of approaches/landings required by the conversion training if the type/class or the variant of the aircraft type or class has the same or similar operating procedures, handling characteristics and performance characteristics as the previously operated aircraft type or class.
(d) Flight crew with reduced required landing distance operations experience with the operator may undertake an abbreviated ground, FSTD and/or flight training course according to the following conditions:
(1) when changing aircraft type or class, the abbreviated course should include at least the content of the conversion training;
(2) when changing to a different variant of aircraft within the same type or class rating that has the same or similar operating procedures, handling characteristics and performance characteristics, as the previously operated aircraft type or class, a difference course or familiarisation appropriate to the change of variant should fulfil the abbreviated course’s purposes; and
(3) when changing to a different variant of aircraft within the same type or class rating that has significantly different operating procedures, handling characteristics and performance characteristics, the abbreviated course should include the content of the conversion training.
GROUND TRAINING
(a) The initial ground training course for reduced required landing distance operations should include at least the following:
(1) operational procedures and limitations, including flight preparation and planning;
(2) characteristics of the runway visual aids and runway markings;
(3) aircraft performance related to reduced required landing distance operations, including:
(i) aircraft-specific decelerating devices and equipment;
(ii) items that increase the aircraft landing distance, e.g. excess speed at touchdown, threshold crossing height, delayed brake application, delayed spoiler/speed brake or thrust reverser application; and
(iii) runway surface conditions;
(4) in-flight assessment of landing performance, including maximum landing masses and runway conditions;
(5) stabilised approach criteria;
(6) correct vertical flight path after the DA/MDA;
(7) correct flare, touchdown and braking techniques;
(8) touchdown within the appropriate touchdown zone;
(9) recognition of failure of aircraft equipment affecting aircraft performance, and action to be taken in that event;
(10) flight crew task allocation and pilot monitoring duties, including monitoring of the activation of deceleration devices;
(11) go-around/balked-landing criteria and decision-making;
(12) selection of precision approaches versus non-precision approaches if both are available; and
(13) qualification requirements for pilots to obtain and retain reduced required landing distance operations, including aerodrome landing analysis programme (ALAP) procedures.
FSTD TRAINING AND/OR FLIGHT TRAINING
(a) FSTD and/or flight training should be undertaken by all flight crew on flight duty at the controls during landing when performing reduced required landing distance operations.
(b) FSTD and/or flight training for reduced required landing distance operations should include checks of equipment functionality, both on the ground and in flight.
(c) Initial reduced required landing distance operations training should consist of a minimum of two approaches and landings to include at least the following exercises which may be combined:
(1) an approach and landing at the maximum landing mass;
(2) an approach and landing without the use of visual approach;
(3) a landing on a wet runway;
(4) a landing with crosswind;
(5) a malfunction of a stopping device on landing; and
(6) a go-around/balked landing.
(d) Special emphasis should be given to the following items:
(1) in-flight assessment of landing performance;
(2) stabilised approach, recognition of an unstable approach and, consequentially, a go-around;
(3) flight crew task allocation and pilot monitoring duties, including monitoring of the activation of deceleration devices;
(4) timely and correct activation of deceleration devices;
(5) correct flare technique; and
(6) landing within the appropriate touchdown zone.
CONVERSION TRAINING
Flight crew members should complete the following reduced required landing distance operations training if converting to a new type or class or variant of aircraft in which reduced required landing distance operations will be conducted.
(a) Ground training, taking into account the flight crew member’s reduced required landing distance operations experience.
(b) FSTD training and/or flight training.
RECURRENT TRAINING AND CHECKING
(a) The operator should ensure that in conjunction with the normal recurrent training and operator’s proficiency checks, the pilot’s knowledge and ability to perform the tasks associated with reduced required landing distance operations are adequate.
(b) The items of the ground training should cover a 3-year period.
(c) An annual reduced required landing distance operations training should consist of a minimum of two approaches and landings so that it includes at least the following exercises which may be combined:
(1) an approach and landing at the maximum landing mass;
(2) an approach and landing without the use of visual approach;
(3) a landing on a wet runway;
(4) a malfunction of a stopping device on landing; and
(5) a go-around/balked landing.
(6) Operations in crosswind conditions
FLIGHT CREW QUALIFICATION AND EXPERIENCE
(a) Flight crew qualification and experience are specific to the operator and type of aircraft operated.
(b) The operator should ensure that each flight crew member successfully completes the specified FSTD and/or flight training before conducting reduced required landing distance operations.
(c) The operator should ensure that no inexperienced flight crew members, as defined in AMC1.ORO.FC.200(a), perform an approach and landing with reduced required landing distance operations.
AMC2 CAT.POL.A.255(b)(2)(iv) Approval of reduced required landing distance operations
ED Decision 2021/005/R
MONITORING
(a) Reduced required landing distance operations should be continuously monitored by the operator to detect any undesirable trends before they become hazardous.
(b) A flight data monitoring (FDM) programme, as required by ORO.AOC.130, is an acceptable method to monitor operational risks related to reduced required landing distance operations.
(c) When an FDM programme is in use, it should include FDM events or FDM measurements relevant for monitoring the risk of runway excursions at landing.
(d) When FDM is neither required by ORO.AOC.130, nor implemented on a voluntary basis, flight crew reports should be used. Specific guidance for reporting events and exceedances during reduced required landing distance operations should be provided to the flight crew.
GM1 CAT.POL.A.255(b)(2)(iv) Approval of reduced required landing distance operations
ED Decision 2021/005/R
GENERAL
Flight crew training should be conducted preferably at aerodromes representative of the intended operations. An FSTD generic aerodrome with the same characteristics of an aerodrome requiring the reduced required landing distance is also acceptable for the initial and recurrent training.
GM2 CAT.POL.A.255(b)(2)(iv) Approval of reduced required landing distance operations
ED Decision 2021/005/R
MONITORING
(a) Although ORO.AOC.130 requires an FDM programme only for aeroplanes with a maximum certified take-off mass (MCTOM) of more than 27 000 kg, FDM may be used voluntarily on aeroplanes having a lower MCTOM. It is recommended for all operators conducting reduced required landing distance operations.
(b) Guidance on the definition of FDM events and FDM measurements relevant for monitoring the risk of runway excursion at landing may be found in the publications of the European Operators Flight Data Monitoring (EOFDM) forum.
AMC1 CAT.POL.A.255(b)(2)(v) Approval of reduced required landing distance operations
ED Decision 2021/005/R
AERODROME LANDING ANALYSIS PROGRAMME (ALAP)
The intent of an ALAP is to ensure that the aerodrome critical data related to landing performance in reduced required landing distance operations is known and taken into account in order to avoid any further increase of the landing distance. Two important aerodrome-related variables largely contribute to increasing the landing distance: landing (ground) speed and deceleration capability. Related factors to consider should include at least the following elements:
(a) Topography
Terrain around the aerodrome should be considered. High, fast-rising terrain may require special approach or decision points, missed approach or balked landing procedures and may affect landing performance. Aerodromes located on top of hilly terrain or downwind of mountainous terrain may occasionally experience conditions of wind shear and gusts. Such conditions are particularly relevant during the landing manoeuvre, particularly during the flare, and may increase landing distance.
(b) Runway conditions
Runway characteristics, such as unknown slope and surface composition, can cause the actual landing distance to be longer than the calculated landing distance. The braking action always impacts the landing distance required as it deteriorates. To this regard, consideration should be given to, and information obtained on, the maintenance status of the runway, as a wet runway surface may be significantly degraded due to poor aerodrome maintenance.
(c) Aerodrome or area weather
Some aerodromes may not have current weather reports and forecast available for flight planning. Others may have automated observations for operational use. Others may depend on the weather forecast of a nearby aerodrome. Area forecasts are also valuable in evaluating weather conditions for a particular operation. Comparing forecasted conditions to current conditions provides insight on upcoming changes as weather systems move and forecasts are updated. Longer flight segments may lean more heavily on the forecast for the estimated time of arrival (ETA), as current conditions may change significantly as weather systems move. The most important factors that should be considered are contained in AMC1 CAT.OP.MPA.300(a), AMC1 CAT.OP.MPA.311, GM1 CAT.OP.MPA.311, GM1 CAT.OP.MPA.303 and GM2 CAT.OP.MPA.303.
(d) Adverse weather
Adverse weather conditions include, but are not restricted to, thunderstorms, showers, downbursts, squall lines, tornadoes, moderate or severe turbulence on approach, heavy precipitation, wind shear and icing conditions. In general, all weather phenomena having the potential to increase the landing distance should be carefully assessed. Among these, tailwind is particularly relevant.
Wind variations should be carefully monitored as they may lead to variations in the reported and/or actual wind at the touchdown zone. Due consideration should be given also to the crosswind perpendicular to the landing runway as a slight variation in the direction of the crosswind may result in a considerable tailwind component.
(e) Runway safety margins
Displaced thresholds, aerodrome construction, and temporary obstacles (such as cranes and drawbridges) may impact the runway length available for landing. Notices to airmen (NOTAMs) must be consulted during the flight preparation. Another safety margin is the size and adequacy of the runway strip and the runway end safety area (RESA). A well-designed and well-maintained runway strip and RESA decrease the risk of damaging the aircraft in case of a runway excursion. ICAO Annex 14 provides the Standards and Recommended Practices (SARPs) to this regard.
GM1 CAT.POL.A.255(b)(2)(v) Approval of reduced required landing distance operations
ED Decision 2021/005/R
AERODROME LANDING ANALYSIS PROGRAMME (ALAP) — AERODROME FACILITIES
The ALAP may also consider the services that are available at the aerodrome. Services such as communications, maintenance, and fuelling, availability of adequate rescue and firefighting services (RFFS) and medical services may have an impact on operations to and from that aerodrome, though not directly related to the landing distance. It is also worth considering whether the aerodrome is only meeting ICAO and national standards or also ICAO recommendations, as well as when the aerodrome bearing ratios are below the design and maintenance criteria indicated in ICAO Doc 9157 ‘Aerodrome Design Manual’.
AMC1 CAT.POL.A.255(b)(2)(vi) Approval of reduced required landing distance operations
ED Decision 2021/005/R
EQUIPMENT AFFECTING LANDING PERFORMANCE
Equipment affecting landing performance typically includes flaps, slats, spoilers, brakes, anti-skid, autobrakes, reversers, etc. The operator should establish procedures to identify, based on the aircraft characteristics, those systems and the equipment that are performance relevant, and to ensure that they are verified to be operative before commencing the flight. Appropriate entries should be included in the minimum equipment list (MEL) to prohibit dispatch with such equipment inoperative when conducting reduced required landing distance operations.
GM1 CAT.POL.A.255(b)(2)(vi) Approval of reduced required landing distance operations
ED Decision 2021/005/R
EQUIPMENT AFFECTING LANDING PERFORMANCE
Should any item of equipment affecting landing performance become inoperative during flight, the failure will be dealt with in accordance with the abnormal/emergency procedures established in the OM and, based on the prevailing conditions for the remainder of the flight, the commander will decide upon the discontinuation of the planned operation of reduced required landing distance.
AMC1 CAT.POL.A.255(b)(2)(vii) Approval of reduced required landing distance operations
ED Decision 2021/005/R
RECENCY
Flight crew conducting reduced landing distance operations should perform at least two landings with reduced landing distance, either in actual operations or in an FSTD, performed within the validity period of the operator proficiency check (OPC).
AMC1 CAT.POL.A.255(b)(2)(ix) Approval of reduced required landing distance operations
ED Decision 2021/005/R
ADDITIONAL AERODROME CONDITIONS
(a) Operators should establish procedures to ensure that:
(1) the aerodrome information is obtained from an authoritative source, or when this is not available, from a source that has been verified by the operator to meet quality standards that are adequate for the intended use;
(2) any change reducing landing distances that has been declared by the aerodrome operator has been taken into account; and
(3) no steep approaches, screen heights lower than 35 ft or higher than 60 ft, operations outside the stabilised approach criteria, or low-visibility operations are required at the aerodrome when reduced required landing distance operations are conducted.
(b) Additional aerodrome conditions related to aeroplane type characteristics, orographic characteristics in the approach area, available approach aids and missed approach/balked landing considerations, as well as operating limitations, should also be taken into account.
(c) When assessing the aerodrome characteristics and the level of risk of the aeroplane undershooting or overrunning the runway, the operator should consider the nature and location of any hazard beyond the runway end, including the topography and obstruction environment beyond the runway strip, the length of the RESA and the effectiveness of any other mitigation measures that may be in place to reduce the likelihood and the consequences of a runway overrun.
CHAPTER 3 – Performance class B
Regulation (EU) 2017/363
(a) Unless approved by the competent authority in accordance with Annex V (Part-SPA), Subpart L — SINGLE- ENGINED TURBINE AEROPLANE OPERATIONS AT NIGHT OR IN IMC (SET-IMC), the operator shall not operate a single-engined aeroplane:
(1) at night; or
(2) in IMC, except under special VFR.
(b) The operator shall treat two-engined aeroplanes that do not meet the climb requirements of CAT.POL.A.340 as single-engined aeroplanes.
Regulation (EU) No 965/2012
(a) The take-off mass shall not exceed the maximum take-off mass specified in the AFM for the pressure altitude and the ambient temperature at the aerodrome of departure.
(b) The unfactored take-off distance, specified in the AFM, shall not exceed:
(1) when multiplied by a factor of 1,25, the take-off run available (TORA); or
(2) when stop way and/or clearway is available, the following:
(i) the TORA;
(ii) when multiplied by a factor of 1,15, the take-off distance available (TODA); or
(iii) when multiplied by a factor of 1,3, the ASDA.
(c) When showing compliance with (b), the following shall be taken into account:
(1) the mass of the aeroplane at the commencement of the take-off run;
(2) the pressure altitude at the aerodrome;
(3) the ambient temperature at the aerodrome;
(4) the runway surface condition and the type of runway surface;
(5) the runway slope in the direction of take-off; and
(6) not more than 50 % of the reported headwind component or not less than 150 % of the reported tailwind component.
RUNWAY SURFACE CONDITION
(a) Unless otherwise specified in the AFM or other performance or operating manuals from the manufacturer, the variables affecting the take-off performance and the associated factors that should be applied to the AFM data are shown in Table 1 below. They should be applied in addition to the operational factors as prescribed in CAT.POL.A.305.
Table 1
Runway surface condition — Variables
|
Surface type |
Condition |
Factor |
|
Grass (on firm soil) up to 20 cm long |
Dry |
1.2 |
|
up to 20 cm long |
Wet |
1.3 |
|
Paved |
Wet |
1.0 |
(b) The soil should be considered firm when there are wheel impressions but no rutting.
(c) When taking off on grass with a single-engined aeroplane, care should be taken to assess the rate of acceleration and consequent distance increase.
(d) When making a rejected take-off on very short grass that is wet and with a firm subsoil, the surface may be slippery, in which case the distances may increase significantly.
(e) The determination of take-off performance data for wet and contaminated runways, when such data is available, should be based on the reported runway surface condition in terms of contaminant and depth.
RUNWAY SLOPE
Unless otherwise specified in the AFM, or other performance or operating manuals from the manufacturer, the take-off distance should be increased by 5 % for each 1 % of upslope except that correction factors for runways with slopes in excess of 2 % should only be applied when the operator has demonstrated to the competent authority that the necessary data in the AFM or the operations manual contain the appropriated procedures and the crew is trained to take-off in runway with slopes in excess of 2 %.
RUNWAY SURFACE CONDITION
(a) Due to the inherent risks, operations from contaminated runways are inadvisable, and should be avoided whenever possible. Therefore, it is advisable to delay the take-off until the runway is cleared.
(b) Where this is impracticable, the commander should also consider the excess runway length available including the criticality of the overrun area.
CAT.POL.A.310 Take-off obstacle clearance – multi-engined aeroplanes
Regulation (EU) No 379/2014
(a) The take-off flight path of aeroplanes with two or more engines shall be determined in such a way that the aeroplane clears all obstacles by a vertical distance of at least 50 ft, or by a horizontal distance of at least 90 m plus 0,125 × D, where D is the horizontal distance travelled by the aeroplane from the end of the TODA or the end of the take-off distance if a turn is scheduled before the end of the TODA, except as provided in (b) and (c). For aeroplanes with a wingspan of less than 60 m, a horizontal obstacle clearance of half the aeroplane wingspan plus 60 m plus 0,125 × D may be used. It shall be assumed that:
(1) the take-off flight path begins at a height of 50 ft above the surface at the end of the take-off distance required by CAT.POL.A.305(b) and ends at a height of 1 500 ft above the surface;
(2) the aeroplane is not banked before the aeroplane has reached a height of 50 ft above the surface, and thereafter the angle of bank does not exceed 15°;
(3) failure of the critical engine occurs at the point on the all engine take-off flight path where visual reference for the purpose of avoiding obstacles is expected to be lost;
(4) the gradient of the take-off flight path from 50 ft to the assumed engine failure height is equal to the average all-engines gradient during climb and transition to the en-route configuration, multiplied by a factor of 0,77; and
(5) the gradient of the take-off flight path from the height reached in accordance with (a)(4) to the end of the take-off flight path is equal to the OEI en-route climb gradient shown in the AFM.
(b) For cases where the intended flight path does not require track changes of more than 15°, the operator does not need to consider those obstacles that have a lateral distance greater than:
(1) 300 m, if the flight is conducted under conditions allowing visual course guidance navigation, or if navigational aids are available enabling the pilot to maintain the intended flight path with the same accuracy; or
(2) 600 m, for flights under all other conditions.
(c) For cases where the intended flight path requires track changes of more than 15°, the operator does not need to consider those obstacles that have a lateral distance greater than:
(1) 600 m, for flights under conditions allowing visual course guidance navigation; or
(2) 900 m, for flights under all other conditions.
(d) When showing compliance with (a) to (c), the following shall be taken into account:
(1) the mass of the aeroplane at the commencement of the take-off run;
(2) the pressure altitude at the aerodrome;
(3) the ambient temperature at the aerodrome; and
(4) not more than 50 % of the reported headwind component or not less than 150 % of the reported tailwind component.
(e) The requirements in (a)(3), (a)(4), (a)(5), (b)(2) and (c)(2) shall not be applicable to VFR operations by day.
TAKE-OFF FLIGHT PATH — VISUAL COURSE GUIDANCE NAVIGATION
(a) In order to allow visual course guidance navigation, the weather conditions prevailing at the time of operation, including ceiling and visibility, should be such that the obstacle and/or ground reference points can be seen and identified. For VFR operations by night, the visual course guidance should be considered available when the flight visibility is 1 500 m or more.
(b) The operations manual should specify, for the aerodrome(s) concerned, the minimum weather conditions that enable the flight crew to continuously determine and maintain the correct flight path with respect to ground reference points so as to provide a safe clearance with respect to obstructions and terrain as follows:
(1) the procedure should be well defined with respect to ground reference points so that the track to be flown can be analysed for obstacle clearance requirements;
(2) the procedure should be within the capabilities of the aeroplane with respect to forward speed, bank angle and wind effects;
(3) a written and/or pictorial description of the procedure should be provided for crew use; and
(4) the limiting environmental conditions should be specified (e.g. wind, cloud, visibility, day/night, ambient lighting, obstruction lighting).
TAKE-OFF FLIGHT PATH CONSTRUCTION
(a) For demonstrating that the aeroplane clears all obstacles vertically, a flight path should be constructed consisting of an all-engines segment to the assumed engine failure height, followed by an engine-out segment. Where the AFM does not contain the appropriate data, the approximation given in (b) may be used for the all-engines segment for an assumed engine failure height of 200 ft, 300 ft, or higher.
(b) Flight path construction
(1) All-engines segment (50 ft to 300 ft)
The average all-engines gradient for the all-engines flight path segment starting at an altitude of 50 ft at the end of the take-off distance ending at or passing through the 300 ft point is given by the following formula:
The factor of 0.77 as required by CAT.POL.A.310 is already included where:
Y300 = average all-engines gradient from 50 ft to 300 ft;
YERC = scheduled all engines en-route gross climb gradient;
VERC = en-route climb speed, all engines knots true airspeed (TAS);
V2 = take-off speed at 50 ft, knots TAS;
(2) All-engines segment (50 ft to 200 ft)
This may be used as an alternative to (b)(1) where weather minima permit. The average all-engines gradient for the all-engines flight path segment starting at an altitude of 50 ft at the end of the take-off distance ending at or passing through the 200 ft point is given by the following formula:
The factor of 0.77 as required by CAT.POL.A.310 is already included where:
Y200 = average all-engines gradient from 50 ft to 200 ft;
YERC = scheduled all engines en-route gross climb gradient;
VERC = en-route climb speed, all engines, knots TAS;
V2 = take-off speed at 50 ft, knots TAS.
(3) All-engines segment (above 300 ft)
The all-engines flight path segment continuing from an altitude of 300 ft is given by the AFM en-route gross climb gradient, multiplied by a factor of 0.77.
(4) The OEI flight path
The OEI flight path is given by the OEI gradient chart contained in the AFM.
OBSTACLE CLEARANCE IN LIMITED VISIBILITY
(a) Unlike the Certification Specifications applicable for performance class A aeroplanes, those for performance class B aeroplanes do not necessarily provide for engine failure in all phases of flight. It is accepted that performance accountability for engine failure need not be considered until a height of 300 ft is reached.
(b) The weather minima given up to and including 300 ft imply that if a take-off is undertaken with minima below 300 ft, an OEI flight path should be plotted starting on the all-engines take-off flight path at the assumed engine failure height. This path should meet the vertical and lateral obstacle clearance specified in CAT.POL.A.310. Should engine failure occur below this height, the associated visibility is taken as being the minimum that would enable the pilot to make, if necessary, a forced landing broadly in the direction of the take-off. At or below 300 ft, a circle and land procedure is extremely inadvisable. The weather minima provisions specify that, if the assumed engine failure height is more than 300 ft, the visibility should be at least 1 500 m and, to allow for manoeuvring, the same minimum visibility should apply whenever the obstacle clearance criteria for a continued take-off cannot be met.
TAKE-OFF FLIGHT PATH CONSTRUCTION
(a) This GM provides examples to illustrate the method of take-off flight path construction given in AMC2 CAT.POL.A.310. The examples are based on an aeroplane for which the AFM shows, at a given mass, altitude, temperature and wind component the following performance data:
— factored take-off distance – 1 000 m;
— take-off speed, V2 – 90 kt;
— en-route climb speed, VERC – 120 kt;
— en-route all-engines climb gradient, YERC – 0.2;
— en-route OEI climb gradient, YERC-1 – 0.032.
(1) Assumed engine failure height 300 ft
The average all-engines gradient from 50 ft to 300 ft may be read from Figure 1 or calculated with the following formula:
The factor of 0.77 as required by CAT.POL.A.310 is already included where:
— Y300 = average all-engines gradient from 50 ft to 300 ft;
— YERC = scheduled all engines en-route gross climb gradient;
— VERC = en-route climb speed, all engines knots TAS; and
— V2 = take-off speed at 50 ft, knots TAS.
Figure 1
Assumed engine failure height 300 ft
(2) Assumed engine failure height 200 ft
The average all-engines gradient from 50 ft to 200 ft may be read from Figure 2 or calculated with the following formula:
The factor of 0.77 as required by CAT.POL.A.310 is already included where:
— Y200 = average all-engines gradient from 50 ft to 200 ft;
— YERC = scheduled all engines en-route gross gradient;
— VERC = en-route climb speed, all engines, knots TAS; and
— V2 = take-off speed at 50 ft, knots TAS.
Figure 2
Assumed engine failure height 200 ft
(3) Assumed engine failure height less than 200 ft
Construction of a take-off flight path is only possible if the AFM contains the required flight path data.
(4) Assumed engine failure height more than 300 ft
The construction of a take-off flight path for an assumed engine failure height of 400 ft is illustrated below.
Figure 3
Assumed engine failure height less than 200 ft
CAT.POL.A.315 En-route – multi-engined aeroplanes
Regulation (EU) No 965/2012
(a) The aeroplane, in the meteorological conditions expected for the flight and in the event of the failure of one engine, with the remaining engines operating within the maximum continuous power conditions specified, shall be capable of continuing flight at or above the relevant minimum altitudes for safe flight stated in the operations manual to a point of 1 000 ft above an aerodrome at which the performance requirements can be met.
(b) It shall be assumed that, at the point of engine failure:
(1) the aeroplane is not flying at an altitude exceeding that at which the rate of climb equals 300 ft per minute with all engines operating within the maximum continuous power conditions specified; and
(2) the en-route gradient with OEI shall be the gross gradient of descent or climb, as appropriate, respectively increased by a gradient of 0,5 %, or decreased by a gradient of 0,5 %.
CRUISING ALTITUDE
(a) The altitude at which the rate of climb equals 300 ft per minute is not a restriction on the maximum cruising altitude at which the aeroplane can fly in practice, it is merely the maximum altitude from which the driftdown procedure can be planned to start.
(b) Aeroplanes may be planned to clear en-route obstacles assuming a driftdown procedure, having first increased the scheduled en-route OEI descent data by 0.5 % gradient.
CAT.POL.A.320 En-route – single-engined aeroplanes
Regulation (EU) 2017/363
(a) In the meteorological conditions expected for the flight, and in the event of engine failure, the aeroplane shall be capable of reaching a place at which a safe forced landing can be made, unless the operator is approved by the competent authority in accordance with Annex V (Part-SPA), Subpart L — SINGLE-ENGINED TURBINE AEROPLANE OPERATIONS AT NIGHT OR IN IMC (SET-IMC) and makes use of a risk period.
(b) For the purposes of point (a), it shall be assumed that, at the point of engine failure:
(1) the aeroplane is not flying at an altitude exceeding that at which the rate of climb equals 300 ft per minute, with the engine operating within the maximum continuous power conditions specified; and
(2) the en-route gradient is the gross gradient of descent increased by a gradient of 0,5 %.
ENGINE FAILURE
CAT.POL.A.320requires the operator not approved by the competent authority in accordance with Subpart L (SET-IMC) of Annex V (Part-SPA) to Regulation (EU) No 965/2012, and not making use of a risk period, to ensure that in the event of an engine failure, the aeroplane should be capable of reaching a point from which a safe forced landing can be made. Unless otherwise specified by the competent authority, this point should be 1 000 ft above the intended landing area.
ENGINE FAILURE
Considerations for the operator not approved by the competent authority in accordance with Subpart L (SET-IMC) of Annex V (Part-SPA) to Regulation (EU) No 965/2012, and not making use of a risk period:
(a) In the event of an engine failure, single-engined aeroplanes have to rely on gliding to a point suitable for a safe forced landing. Such a procedure is clearly incompatible with flight above a cloud layer that extends below the relevant minimum safe altitude.
(b) The operator should first increase the scheduled engine-inoperative gliding performance data by 0.5 % gradient when verifying the en-route clearance of obstacles and the ability to reach a suitable place for a forced landing.
(c) The altitude at which the rate of climb equals 300 ft per minute is not a restriction on the maximum cruising altitude at which the aeroplane can fly in practice, it is merely the maximum altitude from which the engine-inoperative procedure can be planned to start.
RISK PERIOD
In the context of commercial air transport operations with single-engined turbine aeroplanes in instrument meteorological conditions or at night (CAT SET-IMC), a risk period is a period of flight during which no landing site has been selected by the operator.
CAT.POL.A.325 Landing – destination and alternate aerodromes
Regulation (EU) No 965/2012
The landing mass of the aeroplane determined in accordance with CAT.POL.A.105(a) shall not exceed the maximum landing mass specified for the altitude and the ambient temperature expected at the estimated time of landing at the destination aerodrome and alternate aerodrome.
ALTITUDE MEASURING
The operator should use either pressure altitude or geometric altitude for its operation and this should be reflected in the operations manual.
CAT.POL.A.330 Landing – dry runways
Regulation (EU) 2019/1387
(a) The landing mass of the aeroplane determined in accordance with point CAT.POL.A.105(a) for the estimated time of landing at the destination aerodrome and at any alternate aerodrome shall allow a full-stop landing from 50 ft above the threshold within 70 % of the LDA.
(b) By way of derogation from point (a), and where point CAT.POL.A.355 is complied with, the landing mass of the aeroplane determined in accordance with point CAT.POL.A.105(a) for the estimated time of landing at the destination aerodrome shall be such as to allow a full-stop landing from 50 ft above the threshold within 80 % of the LDA.
(c) When determining the landing mass, the operator shall take the following into account:
(1) the altitude at the aerodrome;
(2) not more than 50 % of the headwind component or not less than 150 % of the tailwind component;
(3) the type of runway surface;
(4) the runway slope in the direction of landing.
(d) For steep approach operations, the operator shall use landing distance data factored in accordance with point (a), based on a screen height of less than 60 ft, but not less than 35 ft, and comply with point CAT.POL.A.345.
(e) For short landing operations, the operator shall use landing distance data factored in accordance with point (a), and comply with point CAT.POL.A.350.
(f) For dispatching the aeroplane, the aeroplane shall either:
(1) land on the most favourable runway, in still air;
(2) land on the runway most likely to be assigned considering the probable wind speed and direction, the ground-handling characteristics of the aeroplane and other conditions such as landing aids and terrain.
(g) If the operator is unable to comply with point (f)(2) for the destination aerodrome, the aeroplane shall only be dispatched if an alternate aerodrome is designated that permits full compliance with points (a) to (f).
LANDING DISTANCE CORRECTION FACTORS
(a) Unless otherwise specified in the AFM, or other performance or operating manuals from the manufacturers, the variable affecting the landing performance and the associated factor that should be applied to the AFM data are shown in the table below. It should be applied in addition to the operational factors as prescribed in CAT.POL.A.330 (a) and CAT.POL.A.330(b).
Table 1
Landing distance correction factors
|
Surface type |
Factor |
|
Grass (on firm soil up to 20 cm long) |
1.15 |
(b) The soil should be considered firm when there are wheel impressions but no rutting.
RUNWAY SLOPE
Unless otherwise specified in the AFM, or other performance or operating manuals from the manufacturer, the landing distances required should be increased by 5 % for each 1 % of downslope.
LANDING MASS
CAT.POL.A.330 establishes two considerations in determining the maximum permissible landing mass at the destination and alternate aerodromes.
(a) Firstly, the aeroplane mass will be such that on arrival the aeroplane can be landed within 70 % or 80 %, as applicable, of the LDA on the most favourable (normally the longest) runway in still air. Regardless of the wind conditions, the maximum landing mass for an aerodrome/aeroplane configuration at a particular aerodrome cannot be exceeded.
(b) Secondly, consideration should be given to anticipated conditions and circumstances. The expected wind, or ATC and noise abatement procedures, may indicate the use of a different runway. These factors may result in a lower landing mass than that permitted under (a), in which case dispatch should be based on this lesser mass.
(c) The expected wind referred to in (b) is the wind expected to exist at the time of arrival.
GM1 CAT.POL.A.330(a) Landing — dry runways
ED Decision 2021/005/R
ALTERNATE AERODROMES
The alternate aerodromes for which the landing mass is required to be determined in accordance with CAT.POL.A.330 are:
(a) destination alternate aerodromes;
(b) fuel ERA aerodromes; and
(c) re-dispatch or re-clearance aerodromes.
CAT.POL.A.335 Landing – wet and contaminated runways
Regulation (EU) 2019/1387
(a) When the appropriate weather reports or forecasts indicate that the runway at the estimated time of arrival may be wet, the LDA shall be one of the following distances:
(1) a landing distance provided in the AFM for use on wet runways at time of dispatch, but not less than that required by point CAT.POL.A.330;
(2) if a landing distance is not provided in the AFM for use on wet runways at time of dispatch, at least 115 % of the required landing distance, determined in accordance with point CAT.POL.A.330(a);
(3) a landing distance shorter than that required by point (a)(2), but not less than that required by point CAT.POL.A.330(a), as applicable, if the runway has specific friction improving characteristics and the AFM includes specific additional information for landing distance on that runway type;
(4) by way of derogation from points (a)(1), (a)(2) and (a)(3), for aeroplanes that are approved for reduced landing distance operations under point CAT.POL.A.355, the landing distance determined in accordance with point CAT.POL.A.355(b)(7)(iii).
(b) When the appropriate weather reports or forecasts indicate that the runway at the estimated time of arrival may be contaminated, the landing distance shall not exceed the LDA. The operator shall specify in the operations manual the landing distance data to be applied.
AMC1 CAT.POL.A.335 Landing — wet and contaminated runways
ED Decision 2021/005/R
WET AND CONTAMINATED RUNWAY DATA
The determination of landing performance data should be based on information provided in the OM on the reported RWYCC. The RWYCC is determined by the aerodrome operator using the RCAM and associated procedures defined in Annex V (Part-ADR.OPS) to Regulation (EU) No 139/2014. The RWYCC is reported through an RCR in the SNOWTAM format in accordance with ICAO Annex 15.
LANDING ON WET GRASS RUNWAYS
(a) When landing on very short grass that is wet and with a firm subsoil, the surface may be slippery, in which case the distances may increase by as much as 60 % (1.60 factor).
(b) As it may not be possible for a pilot to determine accurately the degree of wetness of the grass, particularly when airborne, in cases of doubt, the use of the wet factor (1.15) is recommended.
GM2 CAT.POL.A.335 Landing — wet and contaminated runways
ED Decision 2021/005/R
DISPATCH CONSIDERATIONS FOR MARGINAL CASES
The LDTA required by CAT.OP.MPA.303 may, in some cases, and in particular on wet or contaminated runways, exceeds the landing distance considered at the time of dispatch. The requirements for dispatch remain unchanged; however, when the conditions at the time of arrival are expected to be marginal, it is a good practice to carry out at the time of dispatch a preliminary calculation of the LDTA.
GM1 CAT.POL.A.335(a)(1) Landing — wet and contaminated runways
ED Decision 2021/005/R
AFM LANDING DISTANCES FOR WET RUNWAYS
Specific landing distances provided in the AFM for dispatch on wet runways, unless otherwise indicated, include a safety factor, which renders the application of the 15 % safety factor used in CAT.POL.A.335(a)(2) not necessary. This implies that the AFM distance may be presented as factored distance. When the AFM distance is not factored, a safety factor of 15 % should be applied. These distances may be longer or shorter than those resulting from CAT.POL.A.335(a)(2), but when provided, they are intended as a replacement of CAT.POL.A.335(a)(2) and it is mandatory to be used at the time of dispatch.
AMC1 CAT.POL.A.335(a)(3) Landing — wet and contaminated runways
ED Decision 2021/005/R
RUNWAYS WITH FRICTION IMPROVING CHARACTERISTICS
(a) Materials or construction techniques meant to improve the friction characteristics of a runway may be grooved runways, runways treated with PFC or other materials or techniques for which the AFM provides specific performance data.
(b) Before taking the AFM performance credit for such runways, the operator should verify that the runways intended to be operated on are maintained to the extent necessary to ensure the expected improved friction characteristics.
GM1 CAT.POL.A.330 & CAT.POL.A.335 Landing — dry runways & Landing — wet and contaminated runways
ED Decision 2021/005/R
LANDING DISTANCES AND CORRECTIVE FACTORS
The AFM provides performance data for the landing distance under conditions defined in the applicable certification standards. This distance, commonly referred to as the ALD, is the distance from the position on the runway of the screen height to the point where the aeroplane comes to a full stop on a dry runway.
The determination of the ALD is based on the assumption that the landing is performed in accordance with the conditions and the procedures set out in the AFM on the basis of the applicable certification standards.
As a matter of fact, any particular landing may be different from the landing technique that is assumed in the AFM for certification purposes. The aircraft may approach the runway faster and/or higher than assumed; the aircraft may touch down further along the runway than the optimum point; the actual winds and other weather factors may be different from those assumed in the calculation of the ALD; and maximum braking may not be always achievable. For this reason, the LDA is required by CAT.POL.A.330 and CAT.POL.A.335 to be longer than the ALD.
The margins by which the LDA shall exceed the ALD on dry runways, in accordance with CAT.POL.A.330, are shown in the following Table 1.
Table 1: Corrective factors for dry runways
|
Aeroplane category |
Required Margin (dry runway) |
Resulting factor (dry runway) |
|
All aeroplanes |
ALD < 70 % of the LDA |
LDA = at least 1.43 x ALD |
|
Aeroplanes approved under CAT.POL.A.355 |
ALD < 80 % of the LDA |
LDA = at least 1.25 x ALD |
If the runway is wet and the AFM does not provide specific performance data for dispatch on wet runways, a further increase of 15 % of the landing distance on dry runways has to be applied, in accordance with CAT.POL.A.335, as shown in the following Table 2:
Table 2: Corrective factors for wet runways
|
Aeroplane category |
Resulting factor (dry runway) |
|
All aeroplanes |
LDA = at least 1.15 x 1.43 x ALD = 1.64 x ALD |
|
Aeroplanes approved under CAT.POL.A.355 |
LDA = at least 1.15 x 1.25 X ALD = 1.44 x ALD |
However, for aeroplanes approved under CAT.POL.A.355, when landing on wet runways, CAT.POL.A.355 further requires the flight crew to apply the longer of the landing distance resulting from the above table and the landing distance resulting from the application of CAT.OP.MPA.303(b).). If performance information for the assessment of LDTA is not available as per CAT.OP.MPA.303(b)(2), the required landing distance on wet runways should be at least: 1.15 x 1.67 x ALD for turbojet-powered aircraft and 1.15 x 1.43 x ALD for turbopropeller-powered aircraft.
CAT.POL.A.340 Take-off and landing climb requirements
Regulation (EU) No 965/2012
The operator of a two-engined aeroplane shall fulfil the following take-off and landing climb requirements.
(a) Take-off climb
(1) All engines operating
(i) The steady gradient of climb after take-off shall be at least 4 % with:
(A) take-off power on each engine;
(B) the landing gear extended, except that if the landing gear can be retracted in not more than seven seconds, it may be assumed to be retracted;
(C) the wing flaps in the take-off position(s); and
(D) a climb speed not less than the greater of 1,1 VMC (minimum control speed on or near ground) and 1,2 VS1 (stall speed or minimum steady flight speed in the landing configuration).
(2) OEI
(i) The steady gradient of climb at an altitude of 400 ft above the take-off surface shall be measurably positive with:
(A) the critical engine inoperative and its propeller in the minimum drag position;
(B) the remaining engine at take-off power;
(C) the landing gear retracted;
(D) the wing flaps in the take-off position(s); and
(E) a climb speed equal to that achieved at 50 ft.
(ii) The steady gradient of climb shall be not less than 0,75 % at an altitude of 1 500 ft above the take-off surface with:
(A) the critical engine inoperative and its propeller in the minimum drag position;
(B) the remaining engine at not more than maximum continuous power;
(C) the landing gear retracted;
(D) the wing flaps retracted; and
(E) a climb speed not less than 1,2 VS1.
(b) Landing climb
(1) All engines operating
(i) The steady gradient of climb shall be at least 2,5 % with:
(A) not more than the power or thrust that is available eight seconds after initiation of movement of the power controls from the minimum flight idle position;
(B) the landing gear extended;
(C) the wing flaps in the landing position; and
(D) a climb speed equal to VREF (reference landing speed).
(2) OEI
(i) The steady gradient of climb shall be not less than 0,75 % at an altitude of 1 500 ft above the landing surface with:
(A) the critical engine inoperative and its propeller in the minimum drag position;
(B) the remaining engine at not more than maximum continuous power;
(C) the landing gear retracted;
(D) the wing flaps retracted; and
(E) a climb speed not less than 1,2 VS1.
CAT.POL.A.345 Approval of steep approach operations
Regulation (EU) No 965/2012
(a) Steep approach operations using glideslope angles of 4,5° or more and with screen heights of less than 60 ft, but not less than 35 ft, require prior approval by the competent authority.
(b) To obtain the approval, the operator shall provide evidence that the following conditions are met:
(1) the AFM states the maximum approved glideslope angle, any other limitations, normal, abnormal or emergency procedures for the steep approach as well as amendments to the field length data when using steep approach criteria; and
(2) for each aerodrome at which steep approach operations are to be conducted:
(i) a suitable glide path reference system, comprising at least a visual glide path indicating system, is available;
(ii) weather minima are specified; and
(iii) the following items are taken into consideration:
(A) the obstacle situation;
(B) the type of glide path reference and runway guidance;
(C) the minimum visual reference to be required at DH and MDA;
(D) available airborne equipment;
(E) pilot qualification and special aerodrome familiarisation;
(F) AFM limitations and procedures; and
(G) missed approach criteria.
GM1 CAT.POL.A.345(a) Approval of steep approach operations
ED Decision 2021/005/R
SCREEN HEIGHT
For the purpose of steep approach operations, the screen height is the reference height above the runway surface, typically above the runway threshold, from which the landing distance is measured. The screen height is set at 50 ft for normal operations and at another value between 60 ft and 35 ft for steep approach operations.
CAT.POL.A.350 Approval of short landing operations
Regulation (EU) No 965/2012
(a) Short landing operations require prior approval by the competent authority.
(b) To obtain the approval, the operator shall provide evidence that the following conditions are met:
(1) the distance used for the calculation of the permitted landing mass may consist of the usable length of the declared safe area plus the declared LDA;
(2) the use of the declared safe area is approved by the State of the aerodrome;
(3) the declared safe area is clear of obstructions or depressions that would endanger an aeroplane undershooting the runway and no mobile object is permitted on the declared safe area while the runway is being used for short landing operations;
(4) the slope of the declared safe area does not exceed 5 % upward nor 2 % downward slope in the direction of landing;
(5) the usable length of the declared safe area does not exceed 90 m;
(6) the width of the declared safe area is not less than twice the runway width, centred on the extended runway centreline;
(7) the crossing height over the beginning of the usable length of the declared safe area is not less than 50 ft;
(8) weather minima are specified for each runway to be used and are not less than the greater of VFR or NPA minima;
(9) pilot experience, training and special aerodrome familiarisation requirements are specified and met;
(10) additional conditions, if specified by the competent authority, taking into account the aeroplane type characteristics, orographic characteristics in the approach area, available approach aids and missed approach/balked landing considerations.
CAT.POL.A.355 Approval of reduced required landing distance operations
Regulation (EU) 2020/1176
(a) Operations with a landing mass of the aeroplane that allows a full-stop landing within 80 % of the landing distance available (LDA) require prior approval by the competent authority. Such approval shall be obtained for each runway on which operations with reduced required landing distance are conducted.
(b) To obtain the approval referred to in point (a), the operator shall conduct a risk assessment to demonstrate that a level of safety equivalent to that intended by point CAT.POL.A.330(a) is achieved and at least the following conditions are met:
(1) the State of the aerodrome has determined a public interest and operational necessity for the operation, either due to the remoteness of the aerodrome or to physical limitations relating to the extension of the runway;
(2) short landing operations in accordance with point CAT.POL.A.350 and approaches outside stabilised approach criteria approved under point CAT.OP.MPA.115(a) are prohibited;
(3) landing on contaminated runways is prohibited;
(4) a specific control procedure of the touchdown area is defined in the operations manual (OM) and implemented; this procedure shall include adequate go-around and balked-landing instructions when touchdown in the defined area cannot be achieved;
(5) an adequate aerodrome training and checking programme for the flight crew is established;
(6) the flight crew is qualified and has recency in reduced required landing distance operations at the aerodrome concerned;
(7) an aerodrome landing analysis programme (ALAP) is established by the operator to ensure that the following conditions are met:
(i) no tailwind is forecast at the expected time of arrival;
(ii) if the runway is forecast to be wet at the expected time of arrival, the landing distance at dispatch shall either be determined in accordance with point CAT.OP.MPA.303(c), or shall be 115 % of the landing distance determined for dry runways, whichever is longer;
(iii) no forecast contaminated runway conditions exist at the expected time of arrival;
(iv) no forecast adverse weather conditions exist at the expected time of arrival;
(8) operational procedures are established to ensure that:
(i) all the equipment that affects landing performance and landing distance is operative before commencing the flight;
(ii) deceleration devices are correctly used by the flight crew;
(9) specific maintenance instructions and operational procedures are established for the aeroplane’s deceleration devices to enhance the reliability of those systems;
(10) the final approach and landing are conducted under visual meteorological conditions (VMC) only;
(11) additional aerodrome conditions, if specified by the competent authority that has certified the aerodrome, taking into account orographic characteristics of the approach area, available approach aids, missed-approach and balked-landing considerations.
GM1 CAT.POL.A.355(b) Approval of reduced required landing distance operations
ED Decision 2021/005/R
EQUIVALENT LEVEL OF SAFETY
A level of safety equivalent to that intended by CAT.POL.A.330(a) may be achieved when conducting reduced required landing distance operations if mitigating measures are established and implemented. Such measures should address flight crew, aircraft characteristics and performance, aerodromes and operations. It is, however, essential that all conditions established are adhered to as it is the combination of said conditions that achieves the intended level of safety. The operator should in fact also consider the interrelation of the various mitigating measures.
The competent authority may require other mitigating measures in addition to those proposed by the operator.
AMC1 CAT.POL.A.355(b)(4) Approval of reduced required landing distance operations
ED Decision 2021/005/R
CONTROL OF THE TOUCHDOWN AREA
The control of the touchdown area may be ensured by using external references visible from the flight crew compartment. The end of the designated touchdown area should be clearly identified with a ground reference point beyond which a go-around is required. Adequate go-around and balked landing instructions should be established in the OM. A written and/or pictorial description of the procedure should be provided for crew use.
AMC1 CAT.POL.A.355(b)(5) and (b)(6) Approval of reduced required landing distance operations
ED Decision 2021/005/R
TYPE EXPERIENCE
The operator should specify in the OM the minimum pilot’s experience on the aircraft type or class used to conduct such operations.
TRAINING PROGRAMME
(a) Initial training
(1) The aerodrome training programme shall include ground and flight training with a suitably qualified instructor.
(2) Flight training should be carried out on the runway of the intended operations, and should include a suitable number of:
(i) approaches and landings; and
(ii) missed approach/balked landings.
(3) When performing approaches and landings, particular emphasis should be placed on:
(i) stabilised approach criteria;
(ii) accuracy of flare and touchdown;
(iii) positive identification of the ground reference point controlling the touchdown area; and
(iv) correct use of deceleration devices.
(4) These exercises should be conducted in accordance with the specific control procedure of the touchdown area established by the operator and should enable the flight crew to identify the external visual references and the designated touchdown area.
(b) Recurrent training
The operator should ensure that in conjunction with the recurrent training and checking programme required by Subpart FC of Annex III (Part-ORO) to Regulation (EU) No 965/2012, the pilot’s knowledge and ability to perform the tasks associated with this particular operation, for which the pilot is authorised by the operator, are verified.
RECENCY
The operator should define in the OM appropriate recent-experience requirements to ensure that the pilot’s ability to perform an approach to and landing on the intended runway is maintained.
GM1 CAT.POL.A.355(b)(7) Approval of reduced required landing distance operations
ED Decision 2021/005/R
AERODROME LANDING ANALYSIS PROGRAMME (ALAP)
The intent of an ALAP is to ensure that the aerodrome critical data related to landing performance in reduced required landing distance operations is known and taken into account in order to avoid any further increase of the landing distance. Two important aerodrome-related variables largely contribute to increasing the landing distance: landing (ground) speed and deceleration capability. Related factors to consider should include at least the following elements:
(a) Topography
Terrain around the aerodrome should be considered. High, fast-rising terrain may require special approach or decision points, missed approach or balked landing procedures and may affect landing performance. Aerodromes located on top of hilly terrain or downwind of mountainous terrain may occasionally experience conditions of wind shear and gusts. Such conditions are particularly relevant during the landing manoeuvre, particularly during the flare, and may increase landing distance.
(b) Runway conditions
Runway characteristics, such as unknown slope and surface composition, can cause the actual landing distance to be longer than the calculated landing distance. Braking action always impacts the landing distance required as it deteriorates. To this regard, consideration should be given to, and information obtained on, the maintenance status of the runway, as a wet runway surface may be significantly degraded due to poor aerodrome maintenance.
(c) Aerodrome or area weather
Some aerodromes may not have current weather reports and forecast available for flight planning. Others may have automated observations for operational use. Others may depend on the weather forecast of a nearby aerodrome. Area forecasts are also valuable in evaluating weather conditions for a particular operation. Comparing forecasted conditions to current conditions provides insight on upcoming changes as weather systems move and forecasts are updated. Longer flight segments may lean more heavily on the forecast for the ETA, as current conditions may change significantly as weather systems move. The most important factors that should be considered are contained in AMC1 CAT.OP.MPA.300(a), AMC1 CAT.OP.MPA.311, GM1 CAT.OP.MPA.311, GM1 CAT.OP.MPA.303 and GM2 CAT.OP.MPA.303.
(d) Adverse weather
Adverse weather conditions include, but are not restricted to, thunderstorms, showers, downbursts, squall lines, tornadoes, moderate or severe turbulence on approach, heavy precipitation, wind shear and icing conditions. In general, all weather phenomena having the potential to increase the landing distance should be carefully assessed. Among these, tailwind is particularly relevant.
Wind variations should be carefully monitored as they may lead to variations in the reported and/or actual wind at the touchdown zone. Due consideration should be given also to the crosswind perpendicular to the landing runway as a slight variation in the direction of the crosswind may result in a considerable tailwind component.
(e) Runway safety margins
Displaced thresholds, aerodrome construction, and temporary obstacles (such as cranes and drawbridges) may impact the runway length available for landing. NOTAMs must be consulted during the flight preparation. Another safety margin is the size and adequacy of the runway strip and the RESA. A well-designed and well-maintained runway strip and RESA decrease the risk of damaging
GM1 CAT.POL.A.355(b)(7) Approval of reduced required landing distance operations
ED Decision 2021/005/R
AERODROME LANDING ANALYSIS PROGRAMME (ALAP) — AERODROME FACILITIES
The ALAP may also consider the services that are available at the aerodrome. Services such as communications, maintenance, and fuelling, availability of adequate RFFS and medical services may have an impact on operations to and from that aerodrome, though not directly related to the landing distance. It is also worth considering whether the aerodrome is only meeting ICAO and national standards or also ICAO recommendations, as well as when the aerodrome bearing ratios are below the design and maintenance criteria indicated in ICAO Doc 9157 ‘Aerodrome Design Manual’.
AMC1 CAT.POL.A.355(b)(8)(i) Approval of reduced required landing distance operations
ED Decision 2021/005/R
EQUIPMENT AFFECTING LANDING PERFORMANCE
Equipment affecting landing performance typically includes flaps, slats, spoilers, brakes, anti-skid, autobrakes, reversers, etc. The operator should establish procedures to identify, based on the aircraft characteristics, those systems and the equipment that are performance relevant, and to ensure that they are verified to be operative before commencing the flight. Appropriate entries should be included in the MEL to prohibit dispatch with such equipment inoperative when conducting reduced required landing distance operations.
GM1 CAT.POL.A.355(b)(8)(i) Approval of reduced required landing distance operations
ED Decision 2021/005/R
EQUIPMENT AFFECTING LANDING PERFORMANCE
Should any item of equipment affecting landing performance become inoperative during flight, the failure will be dealt with in accordance with the abnormal/emergency procedures established in the OM and, based on the prevailing conditions for the remainder of the flight, the commander will decide upon the discontinuation of the planned operation of reduced required landing distance.
GM1 CAT.POL.A.355(b)(8)(ii) Approval of reduced required landing distance operations
ED Decision 2021/005/R
CORRECT USE OF DECELERATION DEVICES
Flight crew should use full reverse when landing, irrespective of any noise-related restriction on its use, unless this affects the controllability of the aircraft. The use of all stopping devices, including reverse thrust, should commence immediately after touchdown without any delay.
AMC1 CAT.POL.A.355(b)(9) Approval of reduced required landing distance operations
ED Decision 2021/005/R
SPECIFIC MAINTENANCE INSTRUCTIONS
Additional maintenance instructions, such as, but not limited to, more frequent checks for the aircraft’s deceleration devices, especially for the reverse system, should be established by the operator in accordance with the manufacturer’s recommendations, and be included in the operator’s maintenance programme in accordance with Annex I (Part-M) to Regulation (EU) No 1321/2014.
SPECIFIC OPERATIONAL PROCEDURES
The operator should establish procedures for the flight crew to check before take-off the correct deployment of the deceleration devices, such as the reverse system.
AMC1 CAT.POL.A.355(b)(11) Approval of reduced required landing distance operations
ED Decision 2021/005/R
ADDITIONAL AERODROME CONDITIONS
(a) Operators should establish procedures to ensure that:
(1) the aerodrome information is obtained from an authoritative source, or when this is not available, from a source that has been verified by the operator to meet quality standards that are adequate for the intended use; and
(2) any change reducing landing distances that has been declared by the aerodrome operator has been taken into account.
(b) Additional aerodrome conditions related to aeroplane type characteristics, orographic characteristics in the approach area, available approach aids and missed approach/balked landing considerations, as well as operating limitations, should also be taken into account.
(c) When assessing the aerodrome characteristics and the level of risk of the aeroplane undershooting or overrunning the runway, the operator should consider the nature and location of any hazard beyond the runway end, including the topography and obstruction environment beyond the runway strip, the length of the RESA and the effectiveness of any other mitigation measures that may be in place to reduce the likelihood and the consequences of a runway overrun.
CHAPTER 4 – Performance class C
Regulation (EU) No 965/2012
(a) The take-off mass shall not exceed the maximum take-off mass specified in the AFM for the pressure altitude and the ambient temperature at the aerodrome of departure.
(b) For aeroplanes that have take-off field length data contained in their AFM that do not include engine failure accountability, the distance from the start of the take-off roll required by the aeroplane to reach a height of 50 ft above the surface with all engines operating within the maximum take-off power conditions specified, when multiplied by a factor of either:
(1) 1,33 for aeroplanes having two engines;
(2) 1,25 for aeroplanes having three engines; or
(3) 1,18 for aeroplanes having four engines,
shall not exceed the take-off run available (TORA) at the aerodrome at which the take-off is to be made.
(c) For aeroplanes that have take-off field length data contained in their AFM which accounts for engine failure, the following requirements shall be met in accordance with the specifications in the AFM:
(1) the accelerate-stop distance shall not exceed the ASDA;
(2) the take-off distance shall not exceed the take-off distance available (TODA), with a clearway distance not exceeding half of the TORA;
(3) the take-off run shall not exceed the TORA;
(4) a single value of V1 for the rejected and continued take-off shall be used; and
(5) on a wet or contaminated runway the take-off mass shall not exceed that permitted for a take-off on a dry runway under the same conditions.
(d) The following shall be taken into account:
(1) the pressure altitude at the aerodrome;
(2) the ambient temperature at the aerodrome;
(3) the runway surface condition and the type of runway surface;
(4) the runway slope in the direction of take-off;
(5) not more that 50 % of the reported headwind component or not less than 150 % of the reported tailwind component; and
(6) the loss, if any, of runway length due to alignment of the aeroplane prior to take-off.
LOSS OF RUNWAY LENGTH DUE TO ALIGNMENT
(a) The length of the runway that is declared for the calculation of TODA, ASDA and TORA does not account for line-up of the aeroplane in the direction of take-off on the runway in use. This alignment distance depends on the aeroplane geometry and access possibility to the runway in use. Accountability is usually required for a 90°-taxiway entry to the runway and 180°-turnaround on the runway. There are two distances to be considered:
(1) the minimum distance of the main wheels from the start of the runway for determining TODA and TORA, ‘L’; and
(2) the minimum distance of the most forward wheel(s) from the start of the runway for determining ASDA, ‘N’.
Figure 1
Line-up of the aeroplane in the direction of take-off — L and N
Where the aeroplane manufacturer does not provide the appropriate data, the calculation method given in (b) may be used to determine the alignment distance.
(b) Alignment distance calculation
The distances mentioned in (a)(1) and (a)(2) above are:
|
|
90°-entry |
180°-turnaround |
|
L = |
RM + X |
RN + Y |
|
N = |
RM + X + WB |
RN + Y + WB |
where:
RN = A + WN = WB/cos(90°-α) + WN
X = safety distance of outer main wheel during turn to the edge of the runway
Y = safety distance of outer nose wheel during turn to the edge of the runway
Note: Minimum edge safety distances for X and Y are specified in FAA AC 150/5300-13 and ICAO Annex 14, 3.8.3
RN = radius of turn of outer nose wheel
RM = radius of turn of outer main wheel
WN = distance from aeroplane centre-line to outer nose wheel
WM = distance from aeroplane centre-line to outer main wheel
WM = wheel base
α = steering angle.
RUNWAY SLOPE
Unless otherwise specified in the AFM, or other performance or operating manuals from the manufacturers, the take-off distance should be increased by 5 % for each 1 % of upslope. However, correction factors for runways with slopes in excess of 2 % should only be applied when:
(a) the operator has demonstrated to the competent authority that the necessary data in the AFM or the operations manual contain the appropriated procedures; and
(b) the crew is trained to take-off on runways with slopes in excess of 2 %.
ED Decision 2021/005/R
RUNWAY SURFACE CONDITION
The determination of take-off performance data for wet and contaminated runways, when such data is available, should be based on the reported runway surface condition in terms of contaminant and depth.
RUNWAY SURFACE CONDITION
Operation on runways contaminated with water, slush, snow or ice implies uncertainties with regard to runway friction and contaminant drag and, therefore, to the achievable performance and control of the aeroplane during take-off, since the actual conditions may not completely match the assumptions on which the performance information is based. An adequate overall level of safety can, therefore, only be maintained if such operations are limited to rare occasions. In case of a contaminated runway, the first option for the commander is to wait until the runway is cleared. If this is impracticable, he/she may consider a take-off, provided that he/she has applied the applicable performance adjustments, and any further safety measures he/she considers justified under the prevailing conditions.
CAT.POL.A.405 Take-off obstacle clearance
Regulation (EU) No 379/2014
(a) The take-off flight path with OEI shall be determined such that the aeroplane clears all obstacles by a vertical distance of at least 50 ft plus 0,01 × D, or by a horizontal distance of at least 90 m plus 0,125 × D, where D is the horizontal distance the aeroplane has travelled from the end of the TODA. For aeroplanes with a wingspan of less than 60 m, a horizontal obstacle clearance of half the aeroplane wingspan plus 60 m plus 0,125 × D may be used.
(b) The take-off flight path shall begin at a height of 50 ft above the surface at the end of the take-off distance required by CAT.POL.A.400(b) or (c), as applicable, and end at a height of 1500 ft above the surface.
(c) When showing compliance with (a), the following shall be taken into account:
(1) the mass of the aeroplane at the commencement of the take-off run;
(2) the pressure altitude at the aerodrome;
(3) the ambient temperature at the aerodrome; and
(4) not more than 50 % of the reported headwind component or not less than 150 % of the reported tailwind component.
(d) Track changes shall not be allowed up to that point of the take-off flight path where a height of 50 ft above the surface has been achieved. Thereafter, up to a height of 400 ft it is assumed that the aeroplane is banked by no more than 15°. Above 400 ft height bank angles greater than 15°, but not more than 25°, may be scheduled. Adequate allowance shall be made for the effect of bank angle on operating speeds and flight path, including the distance increments resulting from increased operating speeds.
(e) For cases that do not require track changes of more than 15°, the operator does not need to consider those obstacles that have a lateral distance greater than:
(1) 300 m, if the pilot is able to maintain the required navigational accuracy through the obstacle accountability area; or
(2) 600 m, for flights under all other conditions.
(f) For cases that do require track changes of more than 15°, the operator does not need to consider those obstacles that have a lateral distance greater than:
(1) 600 m, if the pilot is able to maintain the required navigational accuracy through the obstacle accountability area; or
(2) 900 m, for flights under all other conditions.
(g) The operator shall establish contingency procedures to satisfy (a) to (f) and to provide a safe route, avoiding obstacles, to enable the aeroplane to either comply with the en-route requirements of CAT.POL.A.410, or land at either the aerodrome of departure or at a take-off alternate aerodrome.
EFFECT OF BANK ANGLES
(a) The AFM generally provides a climb gradient decrement for a 15° bank turn. Unless otherwise specified in the AFM or other performance or operating manuals from the manufacturer, acceptable adjustments to assure adequate stall margins and gradient corrections are provided by the following:
Table 1
Effect of bank angles
|
Bank |
Speed |
Gradient correction |
|
15° |
V2 |
1 x AFM 15° gradient loss |
|
20° |
V2 + 5 kt |
2 x AFM 15° gradient loss |
|
25° |
V2 + 10 kt |
3 x AFM 15° gradient loss |
(b) For bank angles of less than 15°, a proportionate amount may be applied, unless the manufacturer or AFM has provided other data.
REQUIRED NAVIGATIONAL ACCURACY
(a) Navigation systems
The obstacle accountability semi-widths of 300 m and 600 m may be used if the navigation system under OEI conditions provides a two-standard deviation accuracy of 150 m and 300 m respectively.
(b) Visual course guidance
(1) The obstacle accountability semi-widths of 300 m and 600 m may be used where navigational accuracy is ensured at all relevant points on the flight path by use of external references. These references may be considered visible from the flight crew compartment if they are situated more than 45° either side of the intended track and with a depression of not greater than 20° from the horizontal.
(2) For visual course guidance navigation, the operator should ensure that the weather conditions prevailing at the time of operation, including ceiling and visibility, are such that the obstacle and/or ground reference points can be seen and identified. The operations manual should specify, for the aerodrome(s) concerned, the minimum weather conditions that enable the flight crew to continuously determine and maintain the correct flight path with respect to ground reference points, so as to provide a safe clearance with respect to obstructions and terrain as follows:
(i) the procedure should be well defined with respect to ground reference points so that the track to be flown can be analysed for obstacle clearance requirements;
(ii) the procedure should be within the capabilities of the aeroplane with respect to forward speed, bank angle and wind effects;
(iii) a written and/or pictorial description of the procedure should be provided for crew use; and
(iv) the limiting environmental conditions (such as wind, the lowest cloud base, ceiling, visibility, day/night, ambient lighting, obstruction lighting) should be specified.
CAT.POL.A.410 En-route – all engines operating
Regulation (EU) No 965/2012
(a) In the meteorological conditions expected for the flight, at any point on its route or on any planned diversion therefrom, the aeroplane shall be capable of a rate of climb of at least 300 ft per minute with all engines operating within the maximum continuous power conditions specified at:
(1) the minimum altitudes for safe flight on each stage of the route to be flown, or of any planned diversion therefrom, specified in or calculated from the information contained in the operations manual relating to the aeroplane; and
(2) the minimum altitudes necessary for compliance with the conditions prescribed in CAT.POL.A.415 and 420, as appropriate.
Regulation (EU) 2023/217
(a) In the meteorological conditions expected for the flight, in the event of any one engine becoming inoperative at any point on its route or on any planned diversion therefrom and with the other engine(s) operating within the maximum continuous power conditions specified, the aeroplane shall be capable of continuing the flight from the cruising altitude to an aerodrome where a landing can be made in accordance with CAT.POL.A.430 or CAT.POL.A.435, as appropriate. The aeroplane shall clear obstacles within 9,3 km (5 NM) either side of the intended track by a vertical interval of at least:
(1) 1 000 ft, when the rate of climb is zero or greater; or
(2) 2 000 ft, when the rate of climb is less than zero.
(b) The flight path shall have a positive slope at an altitude of 450 m (1 500 ft) above the aerodrome where the landing is assumed to be made after the failure of one engine.
(c) The available rate of climb of the aeroplane shall be taken to be 150 ft per minute less than the gross rate of climb specified.
(d) The width margins provided for in point (a) shall be increased to 18,5 km (10 NM) if the navigational accuracy does not meet at least navigation specification RNAV 5.
(e) Fuel jettisoning is permitted to an extent consistent with reaching the aerodrome where the aeroplane is assumed to land after engine failure with the required fuel reserves in accordance with point CAT.OP.MPA.181, appropriate for an alternate aerodrome, if a safe procedure is used.
ROUTE ANALYSIS
The high terrain or obstacle analysis should be carried out by making a detailed analysis of the route using contour maps of the high terrain, and plotting the highest points within the prescribed corridor width along the route. The next step is to determine whether it is possible to maintain level flight with OEI 1 000 ft above the highest point of the crossing. If this is not possible, or if the associated weight penalties are unacceptable, a drift down procedure must be evaluated, based on engine failure at the most critical point, and must show obstacle clearance during the drift down by at least 2 000 ft. The minimum cruise altitude is determined from the drift down path, taking into account allowances for decision making, and the reduction in the scheduled rate of climb (See Figure 1).
Figure 1
Intersection of the drift down paths
CAT.POL.A.420 En-route – aeroplanes with three or more engines, two engines inoperative
Regulation (EU) 2021/1296
(a) An aeroplane that has three or more engines shall not be away from an aerodrome at which the requirements of point CAT.POL.A.430 for the expected landing mass are met, at any point along the intended track for more than 90 minutes with all engines operating at cruising power or thrust, as appropriate, at standard temperature in still air, unless points (b) to (e) of this point are complied with.
(b) The two-engines-inoperative flight path shall permit the aeroplane to continue the flight, in the expected meteorological conditions, clearing all obstacles within 9,3 km (5 NM) on either side of the inteAnded track by a vertical interval of at least 2 000 ft, to an aerodrome at which the performance requirements applicable for the expected landing mass are met.
(c) The two engines shall be assumed to fail at the most critical point of that portion of the route where the aeroplane is operated for more than 90 minutes, with all engines operating at cruising power or thrust, as appropriate, at standard temperature in still air, away from the aerodrome referred to in point (a).
(d) The expected mass of the aeroplane at the point where the two engines are assumed to fail shall not be less than that which would include sufficient fuel/energy to proceed to an aerodrome where the landing is assumed to be made, and to arrive there at an altitude of at least 1 500 ft (450 m) directly over the landing area, and thereafter, to fly for 15 minutes at cruising power or thrust, as appropriate.
(e) The available rate of climb of the aeroplane shall be 150 ft per minute less than that specified.
(f) The width margins provided for in point (b) shall be increased to 18,5 km (10 NM) if the navigational accuracy does not meet at least navigation specification RNAV 5.
(g) Fuel jettisoning is permitted to an extent consistent with reaching the aerodrome with the required fuel reserves in accordance with point (d), if a safe procedure is used.
CAT.POL.A.425 Landing – destination and alternate aerodromes
Regulation (EU) No 965/2012
The landing mass of the aeroplane determined in accordance with CAT.POL.A.105(a) shall not exceed the maximum landing mass specified in the AFM for the altitude and, if accounted for in the AFM, the ambient temperature expected for the estimated time of landing at the destination aerodrome and alternate aerodrome.
ALTITUDE MEASURING
CAT.POL.A.430 Landing – dry runways
Regulation (EU) 2019/1387
(a) The landing mass of the aeroplane determined in accordance with CAT.POL.A.105(a) for the estimated time of landing at the destination aerodrome and any alternate aerodrome shall allow a full stop landing from 50 ft above the threshold within 70 % of the LDA taking into account:
(1) the altitude at the aerodrome;
(2) not more than 50 % of the headwind component or not less than 150 % of the tailwind component;
(3) the type of runway surface; and
(4) the runway slope in the direction of landing.
(b) For dispatching the aeroplane it shall be assumed that:
(1) the aeroplane will land on the most favourable runway in still air; and
(2) the aeroplane will land on the runway most likely to be assigned considering the probable wind speed and direction, the ground handling characteristics of the aeroplane and other conditions such as landing aids and terrain.
(c) If the operator is unable to comply with (b)(2) for the destination aerodrome, the aeroplane shall only be dispatched if an alternate aerodrome is designated that permits full compliance with (a) and (b).
LANDING DISTANCE CORRECTION FACTORS
(a) Unless otherwise specified in the AFM or other performance or operating manuals from the manufacturers, the variables affecting the landing performance and the associated factors to be applied to the AFM data are shown in the table below. It should be applied in addition to the factor specified in CAT.POL.A.430.
Table 1
Landing distance correction factor
|
Surface type |
factor |
|
Grass (on firm soil up to 20 cm long) |
1.2 |
(b) The soil should be considered firm when there are wheel impressions, but no rutting.
RUNWAY SLOPE
Unless otherwise specified in the AFM, or other performance or operating manuals from the manufacturer, the landing distances required should be increased by 5 % for each 1 % of downslope.
LANDING MASS
CAT.POL.A.430 establishes two considerations in determining the maximum permissible landing mass at the destination and alternate aerodromes.
(a) Firstly, the aeroplane mass will be such that on arrival the aeroplane can be landed within 70 % of the LDA on the most favourable (normally the longest) runway in still air. Regardless of the wind conditions, the maximum landing mass for an aerodrome/aeroplane configuration at a particular aerodrome cannot be exceeded.
(b) Secondly, consideration should be given to anticipated conditions and circumstances. The expected wind, or ATC and noise abatement procedures may indicate the use of a different runway. These factors may result in a lower landing mass than that permitted under (a), in which case dispatch should be based on this lesser mass.
(c) The expected wind referred to in (b) is the wind expected to exist at the time of arrival.
GM1 CAT.POL.A.430(a) Landing — dry runways
ED Decision 2021/005/R
ALTERNATE AERODROMES
The alternate aerodromes for which the landing mass is required to be determined in accordance with CAT.POL.A.430 are:
(a) destination alternate aerodromes;
(b) fuel ERA aerodromes; and
(c) re-dispatch or re-clearance aerodromes.
CAT.POL.A.435 Landing – wet and contaminated runways
Regulation (EU) 2019/1387
(a) When the appropriate weather reports or forecasts indicate that the runway at the estimated time of arrival may be wet, the LDA shall be one of the following distances:
(1) a landing distance provided in the AFM for use on wet runways at time of dispatch, but not less than that required by point CAT.POL.A.430;
(2) if a landing distance is not provided in the AFM for use on wet runways at time of dispatch, at least 115 % of the required landing distance, determined in accordance with point CAT.POL.A.430.
(b) When the appropriate weather reports and/or forecasts indicate that the runway at the estimated time of arrival may be contaminated, the landing distance shall not exceed the LDA. The operator shall specify in the operations manual the landing distance data to be applied.
AMC1 CAT.POL.A.435 Landing — wet and contaminated runways
ED Decision 2021/005/R
WET AND CONTAMINATED RUNWAY DATA
The determination of landing performance data should be based on information provided in the OM on the reported RWYCC. The RWYCC is determined by the aerodrome operator using the RCAM and associated procedures defined in Annex V (Part-ADR.OPS) to Regulation (EU) No 139/2014. The RWYCC is reported through an RCR in the SNOWTAM format in accordance with ICAO Annex 15.
GM1 CAT.POL.A.435 Landing — wet and contaminated runways
ED Decision 2021/005/R
DISPATCH CONSIDERATIONS FOR MARGINAL CASES
The LDTA required by CAT.OP.MPA.303 may, in some cases, and in particular on wet or contaminated runways, exceeds the landing distance considered at the time of dispatch. The requirements for dispatch remain unchanged; however, when the conditions at the time of arrival are expected to be marginal, it is a good practice to carry out at the time of dispatch a preliminary calculation of the LDTA.
GM1 CAT.POL.A.435(a)(1) Landing — wet and contaminated runways
ED Decision 2021/005/R
AFM LANDING DISTANCES FOR WET RUNWAYS
Specific landing distances provided in the AFM for dispatch on wet runways, unless otherwise indicated, include a safety factor, which renders the application of the 15% safety factor used in CAT.POL.A.435(a)(2) not necessary. This implies that the AFM distance may be presented as factored distance. When the AFM distance is not factored, a safety factor of 15 % should be applied. These distances may be longer or shorter than those resulting from CAT.POL.A.435(a)(2), but when provided they are intended as a replacement of CAT.POL.A.435(a)(2) and it is mandatory to be used at the time of dispatch.
GM1 CAT.POL.A.430 & CAT.POL.A.435 Landing — dry runways & Landing — wet and contaminated runways
ED Decision 2021/005/R
LANDING DISTANCES AND CORRECTIVE FACTORS
The AFM provides performance data for landing distance under conditions defined in the applicable certification standards. This distance, commonly referred to as the ALD, is the distance from the position on the runway of the screen height to the point where the aeroplane comes to a full stop on a dry runway.
The determination of the ALD is based on the assumption that the landing is performed in accordance with the conditions and the procedures set out in the AFM on the basis of the applicable certification standards.
As a matter of fact, any particular landing may be different from the landing technique that is assumed in the AFM for certification purposes. The aircraft may approach the runway faster and/or higher than assumed; the aircraft may touch down further along the runway than the optimum point; the actual winds and other weather factors may be different from those assumed in the calculation of the ALD; and maximum braking may not be always achievable. For this reason, the LDA is required by CAT.POL.A.430 and CAT.POL.A.435 to be longer than the ALD.
The margins by which the LDA shall exceed the ALD on dry runways, in accordance with CAT.POL.A.430, are shown in the following Table 1.
Table 1: — Corrective factors for dry runways
|
Aeroplane category |
Required Margin (dry runway) |
Resulting factor (dry runway) |
|
All aeroplanes |
ALD < 70 % of the LDA |
LDA = at least 1.43 x ALD |
If the runway is wet and the AFM does not provide specific performance data for dispatch on wet runways, a further increase of 15 % of the landing distance on dry runways has to be applied, in accordance with CAT.POL.A.435, as shown in the following Table 2.
Table 2: Corrective factors for wet runways
|
Aeroplane category |
Resulting factor (dry runway) |
|
All aeroplanes |
LDA = at least 1.15 x 1.43 x ALD = 1.64 x ALD |
Regulation (EU) No 965/2012
(a) Helicopters shall be operated in accordance with the applicable performance class requirements.
(b) Helicopters shall be operated in performance class 1:
(1) when operated to/from aerodromes or operating sites located in a congested hostile environment, except when operated to/from a public interest site (PIS) in accordance with CAT.POL.H.225; or
(2) when having an MOPSC of more than 19, except when operated to/from a helideck in performance class 2 under an approval in accordance with CAT.POL.H.305.
(c) Unless otherwise prescribed by (b), helicopters that have an MOPSC of 19 or less but more than nine shall be operated in performance class 1 or 2.
(d) Unless otherwise prescribed by (b), helicopters that have an MOPSC of nine or less shall be operated in performance class 1, 2 or 3.
Regulation (EU) No 965/2012
(a) The mass of the helicopter:
(1) at the start of the take-off; or
(2) in the event of in-flight replanning, at the point from which the revised operational flight plan applies,
shall not be greater than the mass at which the applicable requirements of this Section can be complied with for the flight to be undertaken, taking into account expected reductions in mass as the flight proceeds and such fuel jettisoning as is provided for in the relevant requirement.
(b) The approved performance data contained in the AFM shall be used to determine compliance with the requirements of this Section, supplemented as necessary with other data as prescribed in the relevant requirement. The operator shall specify such other data in the operations manual. When applying the factors prescribed in this Section, account may be taken of any operational factors already incorporated in the AFM performance data to avoid double application of factors.
(c) When showing compliance with the requirements of this Section, account shall be taken of the following parameters:
(1) mass of the helicopter;
(2) the helicopter configuration;
(3) the environmental conditions, in particular:
(i) pressure altitude and temperature;
(ii) wind:
(A) except as provided in (C), for take-off, take-off flight path and landing requirements, accountability for wind shall be no more than 50 % of any reported steady headwind component of 5 kt or more;
(B) where take-off and landing with a tailwind component is permitted in the AFM, and in all cases for the take-off flight path, not less than 150 % of any reported tailwind component shall be taken into account; and
(C) where precise wind measuring equipment enables accurate measurement of wind velocity over the point of take-off and landing, wind components in excess of 50 % may be established by the operator, provided that the operator demonstrates to the competent authority that the proximity to the FATO and accuracy enhancements of the wind measuring equipment provide an equivalent level of safety;
(4) the operating techniques; and
(5) the operation of any systems that have an adverse effect on performance.
REPORTED HEADWIND COMPONENT
The reported headwind component should be interpreted as being that reported at the time of flight planning and may be used, provided there is no significant change of unfactored wind prior to take-off.
CAT.POL.H.110 Obstacle accountability
Regulation (EU) No 965/2012
(a) For the purpose of obstacle clearance requirements, an obstacle located beyond the FATO, in the take-off flight path, or the missed approach flight path shall be considered if its lateral distance from the nearest point on the surface below the intended flight path is not further than the following:
(1) For operations under VFR:
(i) half of the minimum width defined in the AFM — or, when no width is defined, ‘0,75 × D’, where D is the largest dimension of the helicopter when the rotors are turning;
(ii) plus, the greater of ‘0,25 × D’ or ‘3 m’;
(iii) plus:
(A) 0,10 × distance DR for operations under VFR by day; or
(B) 0,15 × distance DR for operations under VFR at night.
(2) For operations under IFR:
(i) ‘1,5 D’ or 30 m, whichever is greater, plus:
(A) 0,10 × distance DR, for operations under IFR with accurate course guidance;
(B) 0,15 × distance DR, for operations under IFR with standard course guidance; or
(C) 0,30 × distance DR for operations under IFR without course guidance.
(ii) When considering the missed approach flight path, the divergence of the obstacle accountability area only applies after the end of the take-off distance available.
(3) For operations with initial take-off conducted visually and converted to IFR/IMC at a transition point, the criteria required in (1) apply up to the transition point, and the criteria required in (2) apply after the transition point. The transition point cannot be located before the end of the take-off distance required for helicopters (TODRH) operating in performance class 1 or before the defined point after take-off (DPATO) for helicopters operating in performance class 2.
(b) For take-off using a back-up or a lateral transition procedure, for the purpose of obstacle clearance requirements, an obstacle located in the back-up or lateral transition area shall be considered if its lateral distance from the nearest point on the surface below the intended flight path is not further than:
(1) half of the minimum width defined in the AFM or, when no width is defined, ‘0,75 × D’;
(2) plus the greater of ‘0,25 × D’ or ‘3 m’;
(3) plus:
(i) for operations under VFR by day 0,10 × the distance travelled from the back of the FATO, or
(ii) for operations under VFR at night 0,15 × the distance travelled from the back of the FATO.
(c) Obstacles may be disregarded if they are situated beyond:
(1) 7 × rotor radius (R) for day operations, if it is assured that navigational accuracy can be achieved by reference to suitable visual cues during the climb;
(2) 10 × R for night operations, if it is assured that navigational accuracy can be achieved by reference to suitable visual cues during the climb;
(3) 300 m if navigational accuracy can be achieved by appropriate navigation aids; or
(4) 900 m in all other cases.
COURSE GUIDANCE
Standard course guidance includes automatic direction finder (ADF) and VHF omnidirectional radio range (VOR) guidance.
Accurate course guidance includes ILS, MLS or other course guidance providing an equivalent navigational accuracy.
CHAPTER 2 – Performance class 1
Regulation (EU) No 965/2012
Helicopters operated in performance class 1 shall be certified in category A or equivalent as determined by the Agency.
CATEGORY A AND CATEGORY B
(a) Helicopters that have been certified according to any of the following standards are considered to satisfy the Category A criteria. Provided that they have the necessary performance information scheduled in the AFM, such helicopters are, therefore, eligible for performance class 1 or 2 operations:
(1) certification as Category A under CS-27 or CS-29;
(2) certification as Category A under JAR-27 or JAR-29;
(3) certification as Category A under FAR Part 29;
(4) certification as group A under BCAR Section G; and
(5) certification as group A under BCAR-29.
(b) In addition to the above, certain helicopters have been certified under FAR Part 27 and with compliance with FAR Part 29 engine isolation requirements as specified in FAA Advisory Circular AC 27-1. Provided that compliance is established with the following additional requirements of CS-29:
(1) CS 29.1027(a) Independence of engine and rotor drive system lubrication;
(2) CS 29.1187(e);
(3) CS 29.1195(a) & (b) Provision of a one-shot fire extinguishing system for each engine;
(i) The requirement to fit a fire extinguishing system may be waived if the helicopter manufacturer can demonstrate equivalent safety, based on service experience for the entire fleet showing that the actual incidence of fires in the engine fire zones has been negligible.
(4) CS 29.1197;
(5) CS 29.1199;
(6) CS 29.1201; and
(7) CS 29.1323(c)(1) Ability of the airspeed indicator to consistently identify the take-off decision point,
these helicopters are considered to satisfy the requirement to be certified as equivalent to Category A.
(c) The performance operating rules of JAR-OPS 3, which were transposed into this Part, were drafted in conjunction with the performance requirements of JAR-29 Issue 1 and FAR Part 29 at amendment 29-39. For helicopters certificated under FAR Part 29 at an earlier amendment, or under BCAR section G or BCAR-29, performance data will have been scheduled in the AFM according to these earlier requirements. This earlier scheduled data may not be fully compatible with this Part.
(d) Before any AOC is issued under which performance class 1 or 2 operations are conducted, it should be established that scheduled performance data are available that are compatible with the requirements of performance class 1 and 2 respectively.
(e) Any properly certified helicopter is considered to satisfy the Category B criteria. If appropriately equipped (in accordance with CAT.IDE.H), such helicopters are, therefore, eligible for performance class 3 operations.
Regulation (EU) No 965/2012
(a) The take-off mass shall not exceed the maximum take-off mass specified in the AFM for the procedure to be used.
(b) The take-off mass shall be such that:
(1) it is possible to reject the take-off and land on the FATO in case of the critical engine failure being recognised at or before the take-off decision point (TDP);
(2) the rejected take-off distance required (RTODRH) does not exceed the rejected take-off distance available (RTODAH); and
(3) the TODRH does not exceed the take-off distance available (TODAH).
(4) Notwithstanding (b)(3), the TODRH may exceed the TODAH if the helicopter, with the critical engine failure recognised at TDP can, when continuing the take-off, clear all obstacles to the end of the TODRH by a vertical margin of not less than 10,7 m (35 ft).
(c) When showing compliance with (a) and (b), account shall be taken of the appropriate parameters of CAT.POL.H.105(c) at the aerodrome or operating site of departure.
(d) That part of the take-off up to and including TDP shall be conducted in sight of the surface such that a rejected take-off can be carried out.
(e) For take-off using a backup or lateral transition procedure, with the critical engine failure recognition at or before the TDP, all obstacles in the back-up or lateral transition area shall be cleared by an adequate margin.
THE APPLICATION OF TODRH
The selected height should be determined with the use of AFM data, and be at least 10.7 m (35 ft) above:
(a) the take-off surface; or
(b) as an alternative, a level height defined by the highest obstacle in the take-off distance required.
THE APPLICATION OF TODRH
(a) Introduction
Original definitions for helicopter performance were derived from aeroplanes; hence, the definition of take-off distance owes much to operations from runways. Helicopters on the other hand can operate from runways, confined and restricted areas and rooftop FATOs — all bounded by obstacles. As an analogy, this is equivalent to a take-off from a runway with obstacles on and surrounding it.
It can, therefore, be said that unless the original definitions from aeroplanes are tailored for helicopters, the flexibility of the helicopter might be constrained by the language of operational performance.
This GM concentrates on the critical term ‘take-off distance required (TODRH)’ and describes the methods to achieve compliance with it and, in particular, the alternative procedure described in ICAO Annex 6 Attachment A 4.1.1.3:
(1) the take-off distance required does not exceed the take-off distance available; or
(2) as an alternative, the take-off distance required may be disregarded provided that the helicopter with the critical engine failure recognised at TDP can, when continuing the take-off, clear all obstacles between the end of the take-off distance available and the point at which it becomes established in a climb at VTOSS by a vertical margin of 10.7 m (35 ft) or more. An obstacle is considered to be in the path of the helicopter if its distance from the nearest point on the surface below the intended line of flight does not exceed 30 m or 1.5 times the maximum dimension of the helicopter, whichever is greater.
(b) Definition of TODRH
The definition of TODRH from Annex I is as follows:
‘Take-off distance required (TODRH)’ in the case of helicopters means the horizontal distance required from the start of the take-off to the point at which take-off safety speed (VTOSS), a selected height and a positive climb gradient are achieved, following failure of the critical engine being recognised at the TDP, the remaining engines operating within approved operating limits.
AMC1 CAT.POL.H.205(b)(4) states how the specified height should be determined.
The original definition of TODRH was based only on the first part of this definition.
(c) The clear area procedure (runway)
In the past, helicopters certified in Category A would have had, at the least, a ‘clear area’ procedure. This procedure is analogous to an aeroplane Category A procedure and assumes a runway (either metalled or grass) with a smooth surface suitable for an aeroplane take-off (see Figure 1).
The helicopter is assumed to accelerate down the FATO (runway) outside of the height velocity (HV) diagram. If the helicopter has an engine failure before TDP, it must be able to land back on the FATO (runway) without damage to helicopter or passengers; if there is a failure at or after TDP the aircraft is permitted to lose height — providing it does not descend below a specified height above the surface (usually 15 ft if the TDP is above 15 ft). Errors by the pilot are taken into consideration, but the smooth surface of the FATO limits serious damage if the error margin is eroded (e.g. by a change of wind conditions).
Figure 1
Clear Area take – off
The operator only has to establish that the distances required are within the distance available (take-off distance and reject distance). The original definition of TODRH meets this case exactly.
From the end of the TODRH obstacle clearance is given by the climb gradient of the first or second climb segment meeting the requirement of CAT.POL.H.210 (or for performance class 2 (PC2): CAT.POL.H.315). The clearance margin from obstacles in the take-off flight path takes account of the distance travelled from the end of the take-off distance required and operational conditions (IMC or VMC).
(d) Category A procedures other-than-clear area
Procedures other-than-the-clear area are treated somewhat differently. However, the short field procedure is somewhat of a hybrid as either (a) or (b) of AMC1 CAT.POL.H.205(b)(4) can be utilised (the term ‘helipad’ is used in the following section to illustrate the principle only, it is not intended as a replacement for ‘aerodrome’ or ‘FATO’).
(1) Limited area, restricted area and helipad procedures (other than elevated)
The exact names of the procedure used for other-than-clear area are as many as there are manufacturers. However, principles for obstacle clearance are generic and the name is unimportant.
These procedures (see Figure 2 and Figure 3) are usually associated with an obstacle in the continued take-off area — usually shown as a line of trees or some other natural obstacle. As clearance above such obstacles is not readily associated with an accelerative procedure, as described in (c), a procedure using a vertical climb (or a steep climb in the forward, sideways or rearward direction) is utilised.
Figure 2
Short Field take-off
With the added complication of a TDP principally defined by height together with obstacles in the continued take off area, a drop down to within 15 ft of the take-off surface is not deemed appropriate and the required obstacle clearance is set to 35 ft (usually called ‘min-dip’). The distance to the obstacle does not need to be calculated (provided it is outside the rejected distance required), as clearance above all obstacles is provided by ensuring that helicopter does not descend below the min-dip associated with a level defined by the highest obstacle in the continued take-off area.
Figure 3
Helipad take-off
These procedures depend upon (b) of AMC1 CAT.POL.H.205(b)(4).
As shown in Figure 3, the point at which VTOSS and a positive rate of climb are met defines the TODRH. Obstacle clearance from that point is assured by meeting the requirement of CAT.POL.H.210 (or for PC2, CAT.POL.H.315). Also shown in Figure 3 is the distance behind the helipad which is the backup distance (B/U distance).
(2) Elevated helipad procedures
The elevated helipad procedure (see Figure 4) is a special case of the ground level helipad procedure discussed above.
Figure 4
Elevate Helipad take-off
The main difference is that drop down below the level of the take-off surface is permitted. In the drop down phase, the Category A procedure ensures deck-edge clearance but, once clear of the deck-edge, the 35 ft clearance from obstacles relies upon the calculation of drop down. Subparagraph (b) of AMC1 CAT.POL.H.205(b)(4) is applied.
Although 35 ft is used throughout the requirements, it may be inadequate at particular elevated FATOs that are subject to adverse airflow effects, turbulence, etc.
OBSTACLE CLEARANCE IN THE BACKUP AREA
(a) The requirement in CAT.POL.H.205(e) has been established in order to take into account the following factors:
(1) in the backup: the pilot has few visual cues and has to rely upon the altimeter and sight picture through the front window (if flight path guidance is not provided) to achieve an accurate rearward flight path;
(2) in the rejected take-off: the pilot has to be able to manage the descent against a varying forward speed whilst still ensuring an adequate clearance from obstacles until the helicopter gets in close proximity for landing on the FATO; and
(3) in the continued take-off; the pilot has to be able to accelerate to VTOSS (take-off safety speed for Category A helicopters) whilst ensuring an adequate clearance from obstacles.
(b) The requirements of CAT.POL.H.205(e) may be achieved by establishing that:
(1) in the backup area no obstacles are located within the safety zone below the rearward flight path when described in the AFM (see Figure 1, in the absence of such data in the AFM, the operator should contact the manufacturer in order to define a safety zone);or
(2) during the backup, the rejected take-off and the continued take-off manoeuvres, obstacle clearance is demonstrated to the competent authority.
Figure 1
Rearward flight path
(c) An obstacle, in the backup area, is considered if its lateral distance from the nearest point on the surface below the intended flight path is not further than:
(1) half of the minimum FATO (or the equivalent term used in the AFM) width defined in the AFM (or, when no width is defined 0.75 D, where D is the largest dimension of the helicopter when the rotors are turning); plus
(2) 0.25 times D (or 3 m, whichever is greater); plus
(3) 0.10 for VFR day, or 0.15 for VFR night, of the distance travelled from the back of the FATO (see Figure 2).
Figure 2
Obstacle accountability
APPLICATION FOR ALTERNATIVE TAKE-OFF AND LANDING PROCEDURES
(a) A reduction in the size of the take-off surface may be applied when the operator has demonstrated to the competent authority that compliance with the requirements of CAT.POL.H.205, 210 and 220 can be assured with:
(1) a procedure based upon an appropriate Category A take-off and landing profile scheduled in the AFM;
(2) a take-off or landing mass not exceeding the mass scheduled in the AFM for a hover-out-of-ground-effect one-engine-inoperative (HOGE OEI) ensuring that:
(i) following an engine failure at or before TDP, there are adequate external references to ensure that the helicopter can be landed in a controlled manner; and
(ii) following an engine failure at or after the landing decision point (LDP), there are adequate external references to ensure that the helicopter can be landed in a controlled manner.
(b) An upwards shift of the TDP and LDP may be applied when the operator has demonstrated to the competent authority that compliance with the requirements of CAT.POL.H.205, 210 and 220 can be assured with:
(1) a procedure based upon an appropriate Category A take-off and landing profile scheduled in the AFM;
(2) a take-off or landing mass not exceeding the mass scheduled in the AFM for a HOGE OEI ensuring that:
(i) following an engine failure at or after TDP compliance with the obstacle clearance requirements of CAT.POL.H.205 (b)(4) and CAT.POL.H.210 can be met; and
(ii) following an engine failure at or before the LDP the balked landing obstacle clearance requirements of CAT.POL.H.220 (b) and CAT.POL.H.210 can be met.
(c) The Category A ground level surface area requirement may be applied at a specific elevated FATO when the operator can demonstrate to the competent authority that the usable cue environment at that aerodrome/operating site would permit such a reduction in size.
APPLICATION FOR ALTERNATIVE TAKE-OFF AND LANDING PROCEDURES
The manufacturer’s Category A procedure defines profiles and scheduled data for take-off, climb, performance at minimum operating speed and landing, under specific environmental conditions and masses.
Associated with these profiles and conditions are minimum operating surfaces, take-off distances, climb performance and landing distances; these are provided (usually in graphic form) with the take-off and landing masses and the take-off decision point (TDP) and landing decision point (LDP).
The landing surface and the height of the TDP are directly related to the ability of the helicopter — following an engine failure before or at TDP — to reject onto the surface under forced landing conditions. The main considerations in establishing the minimum size of the landing surface are the scatter during flight testing of the reject manoeuvre, with the remaining engine operating within approved limits, and the required usable cue environment.
Hence, an elevated site with few visual cues — apart from the surface itself — would require a greater surface area in order that the helicopter can be accurately positioned during the reject manoeuvre within the specified area. This usually results in the stipulation of a larger surface for an elevated site than for a ground level site (where lateral cues may be present).
This could have the unfortunate side effect that a FATO that is built 3 m above the surface (and, therefore, elevated by definition) might be out of operational scope for some helicopters — even though there might be a rich visual cue environment where rejects are not problematical. The presence of elevated sites where ground level surface requirements might be more appropriate could be brought to the attention of the competent authority.
It can be seen that the size of the surface is directly related to the requirement of the helicopter to complete a rejected take-off following an engine failure. If the helicopter has sufficient power such that a failure before or at TDP will not lead to a requirement for rejected take-off, the need for large surfaces is removed; sufficient power for the purpose of this GM is considered to be the power required for hover-out-of-ground-effect one-engine-inoperative (HOGE OEI).
Following an engine failure at or after the TDP, the continued take-off path provides OEI clearance from the take-off surface and the distance to reach a point from where climb performance in the first, and subsequent segments, is assured.
If HOGE OEI performance exists at the height of the TDP, it follows that the continued take-off profile, which has been defined for a helicopter with a mass such that a rejected take-off would be required following an engine failure at or before TDP, would provide the same, or better, obstacle clearance and the same, or less, distance to reach a point where climb performance in the first, and subsequent segments, is assured.
If the TDP is shifted upwards, provided that the HOGE OEI performance is established at the revised TDP, it will not affect the shape of the continued take-off profile but should shift the min-dip upwards by the same amount that the revised TDP has been increased — with respect to the basic TDP.
Such assertions are concerned only with the vertical or the backup procedures and can be regarded as achievable under the following circumstances:
(a) when the procedure is flown, it is based upon a profile contained in the AFM — with the exception of the necessity to perform a rejected take-off;
(b) the TDP, if shifted upwards (or upwards and backward in the backup procedure) will be the height at which the HOGE OEI performance is established; and
(c) if obstacles are permitted in the backup area, they should continue to be permitted with a revised TDP.
CAT.POL.H.210 Take-off flight path
Regulation (EU) No 965/2012
(a) From the end of the TODRH with the critical engine failure recognised at the TDP:
(1) The take-off mass shall be such that the take-off flight path provides a vertical clearance, above all obstacles located in the climb path, of not less than 10,7 m (35 ft) for operations under VFR and 10,7 m (35 ft) + 0,01 × distance DR for operations under IFR. Only obstacles as specified in CAT.POL.H.110 have to be considered.
(2) Where a change of direction of more than 15° is made, adequate allowance shall be made for the effect of bank angle on the ability to comply with the obstacle clearance requirements. This turn is not to be initiated before reaching a height of 61 m (200 ft) above the take-off surface unless it is part of an approved procedure in the AFM.
(b) When showing compliance with (a), account shall be taken of the appropriate parameters of CAT.POL.H.105(c) at the aerodrome or operating site of departure.
CAT.POL.H.215 En-route – critical engine inoperative
Regulation (EU) 2023/1020
(a) The mass of the helicopter and flight path at all points along the route, with the critical engine inoperative and the meteorological conditions expected for the flight, shall permit compliance with (1), (2) or (3):
(1) When it is intended that the flight will be conducted at any time out of sight of the surface, the mass of the helicopter permits a rate of climb of at least 50 ft/minute with the critical engine inoperative at an altitude of at least 300 m (1 000 ft), or 600 m (2 000 ft) in areas of mountainous terrain, above all terrain and obstacles along the route within 9,3 km (5 NM) on either side of the intended track.
(2) When it is intended that the flight will be conducted without the surface in sight, the flight path permits the helicopter to continue flight from the cruising altitude to a height of 300 m (1 000 ft) above a landing site where a landing can be made in accordance with CAT.POL.H.220. The flight path clears vertically, by at least 300 m (1 000 ft) or 600 m (2 000 ft) in areas of mountainous terrain, all terrain and obstacles along the route within 9,3 km (5 NM) on either side of the intended track. Drift-down techniques may be used.
(3) When it is intended that the flight will be conducted in VMC with the surface in sight, the flight path permits the helicopter to continue flight from the cruising altitude to a height of 300 m (1 000 ft) above a landing site where a landing can be made in accordance with CAT.POL.H.220, without flying at any time below the appropriate minimum flight altitude. Obstacles within 900 m on either side of the route need to be considered.
(b) When showing compliance with (a)(2) or (a)(3):
(1) the critical engine is assumed to fail at the most critical point along the route;
(2) account is taken of the effects of winds on the flight path;
(3) fuel jettisoning is planned to take place only to an extent consistent with reaching the aerodrome or operating site with the required fuel reserves and using a safe procedure; and
(4) fuel jettisoning is not planned below 1 000 ft above terrain.
(c) The width margins of (a)(1) and (a)(2) shall be increased to 18,5 km (10 NM) if the navigational accuracy cannot be met for 95 % of the total flight time.
[applicable until 24 May 2024 — Regulation (EU) No 965/2012]
(a) The mass of the helicopter and the flight path at all points along the route, with the critical engine inoperative and the meteorological conditions expected for the flight, shall permit compliance with any of the following points:
(1) when it is intended that the flight will be conducted at any time out of sight of the surface, the mass of the helicopter permits a rate of climb of at least 50 ft/minute with the critical engine inoperative at an altitude of at least 300 m (1 000 ft), or 600 m (2 000 ft) in areas of mountainous terrain, above all relevant terrain and obstacles along the route;
(2) when it is intended that the flight will be conducted without the surface in sight, the flight path permits the helicopter to continue flight from the cruising altitude to a height of 300 m (1 000 ft) above a landing site where a landing can be made in accordance with point CAT.POL.H.220; the flight path clears vertically, by at least 300 m (1 000 ft) or 600 m (2 000 ft) in areas of mountainous terrain, all relevant terrain and obstacles along the route; Drift-down techniques may be used;
(3) when it is intended that the flight will be conducted in VMC with the surface in sight, the flight path permits the helicopter to continue flight from the cruising altitude to a height of 300 m (1 000 ft) above a landing site where a landing can be made in accordance with point CAT.POL.H.220, without flying at any time below the appropriate minimum flight altitude; Obstacles shall be considered within a distance on either side of the route as specified for the purpose of determination of the minimum flight altitude in VFR.
(b) When showing compliance with (a)(2) or (a)(3):
(1) the critical engine is assumed to fail at the most critical point along the route;
(2) account is taken of the effects of winds on the flight path;
(3) fuel jettisoning is planned to take place only to an extent consistent with reaching the aerodrome or operating site with the required fuel reserves and using a safe procedure; and
(4) fuel jettisoning is not planned below 1 000 ft above terrain.
[applicable from 25 May 2024 — Implementing Regulation (EU) 2023/1020]
AMC1 CAT.POL.H.215(a)(1);(a)(2) En-route – critical engine inoperative
ED Decision 2023/007/R
RELEVANT TERRAIN AND OBSTACLES IN IFR
All terrain and obstacles along the route within the following distance on either side of the intended track should be considered:
(a) 9.3 km (5 NM) to be increased to 18.5 km (10 NM) if the navigational accuracy cannot be met for 95 % of the total flight time; or
(b) when flying in accordance with PBN procedures, a distance equal to or greater than the required navigation performance.
GM1 CAT.POL.H.215(a)(3) En-route – critical engine inoperative
ED Decision 2023/007/R
RELEVANT TERRAIN AND OBSTACLES IN VFR
The terrain and obstacles to be considered are within the distance on either side of the intended track that is specified in the applicable airspace requirements:
(a) for day VFR, the distances are specified in SERA.5005(f);
(b) for night VFR, the distances are specified in SERA.5005(c), or as authorised by the competent authority.
FUEL JETTISON
The presence of obstacles along the en route flight path may preclude compliance with point CAT.POL.H.215(a)(1) with the planned mass at the critical point along the route. In this case, fuel jettison at the most critical point may be planned, provided that the procedures of point (d) of AMC1 CAT.OP.MPA.191(b)&(c) are complied with.
Regulation (EU) No 965/2012
(a) The landing mass of the helicopter at the estimated time of landing shall not exceed the maximum mass specified in the AFM for the procedure to be used.
(b) In the event of the critical engine failure being recognised at any point at or before the landing decision point (LDP), it is possible either to land and stop within the FATO, or to perform a balked landing and clear all obstacles in the flight path by a vertical margin of 10,7 m (35 ft). Only obstacles as specified in CAT.POL.H.110 have to be considered.
(c) In the event of the critical engine failure being recognised at any point at or after the LDP, it is possible to:
(1) clear all obstacles in the approach path; and
(2) land and stop within the FATO.
(d) When showing compliance with (a) to (c), account shall be taken of the appropriate parameters of CAT.POL.H.105(c) for the estimated time of landing at the destination aerodrome or operating site, or any alternate if required.
(e) That part of the landing from the LDP to touchdown shall be conducted in sight of the surface.
APPLICATION FOR ALTERNATIVE TAKE-OFF AND LANDING PROCEDURES
The manufacturer’s Category A procedure defines profiles and scheduled data for take-off, climb, performance at minimum operating speed and landing, under specific environmental conditions and masses.
Associated with these profiles and conditions are minimum operating surfaces, take-off distances, climb performance and landing distances; these are provided (usually in graphic form) with the take-off and landing masses and the take-off decision point (TDP) and landing decision point (LDP).
The landing surface and the height of the TDP are directly related to the ability of the helicopter — following an engine failure before or at TDP — to reject onto the surface under forced landing conditions. The main considerations in establishing the minimum size of the landing surface are the scatter during flight testing of the reject manoeuvre, with the remaining engine operating within approved limits, and the required usable cue environment.
Hence, an elevated site with few visual cues — apart from the surface itself — would require a greater surface area in order that the helicopter can be accurately positioned during the reject manoeuvre within the specified area. This usually results in the stipulation of a larger surface for an elevated site than for a ground level site (where lateral cues may be present).
This could have the unfortunate side effect that a FATO that is built 3 m above the surface (and, therefore, elevated by definition) might be out of operational scope for some helicopters — even though there might be a rich visual cue environment where rejects are not problematical. The presence of elevated sites where ground level surface requirements might be more appropriate could be brought to the attention of the competent authority.
It can be seen that the size of the surface is directly related to the requirement of the helicopter to complete a rejected take-off following an engine failure. If the helicopter has sufficient power such that a failure before or at TDP will not lead to a requirement for rejected take-off, the need for large surfaces is removed; sufficient power for the purpose of this GM is considered to be the power required for hover-out-of-ground-effect one-engine-inoperative (HOGE OEI).
Following an engine failure at or after the TDP, the continued take-off path provides OEI clearance from the take-off surface and the distance to reach a point from where climb performance in the first, and subsequent segments, is assured.
If HOGE OEI performance exists at the height of the TDP, it follows that the continued take-off profile, which has been defined for a helicopter with a mass such that a rejected take-off would be required following an engine failure at or before TDP, would provide the same, or better, obstacle clearance and the same, or less, distance to reach a point where climb performance in the first, and subsequent segments, is assured.
If the TDP is shifted upwards, provided that the HOGE OEI performance is established at the revised TDP, it will not affect the shape of the continued take-off profile but should shift the min-dip upwards by the same amount that the revised TDP has been increased — with respect to the basic TDP.
Such assertions are concerned only with the vertical or the backup procedures and can be regarded as achievable under the following circumstances:
(a) when the procedure is flown, it is based upon a profile contained in the AFM — with the exception of the necessity to perform a rejected take-off;
(b) the TDP, if shifted upwards (or upwards and backward in the backup procedure) will be the height at which the HOGE OEI performance is established; and
(c) if obstacles are permitted in the backup area, they should continue to be permitted with a revised TDP.
CAT.POL.H.225 Helicopter operations to/from a public interest site
Regulation (EU) 2023/1020
(a) Operations to/from a public interest site (PIS) may be conducted in performance class 2, without complying with CAT.POL.H.310(b) or CAT.POL.H.325(b), provided that all of the following are complied with:
(1) the PIS was in use before 1 July 2002;
(2) the size of the PIS or obstacle environment does not permit compliance with the requirements for operation in performance class 1;
(3) the operation is conducted with a helicopter with an MOPSC of six or less;
(4) the operator complies with CAT.POL.H.305(b)(2) and (b)(3);
(5) the helicopter mass does not exceed the maximum mass specified in the AFM for a climb gradient of 8 % in still air at the appropriate take-off safety speed (VTOSS) with the critical engine inoperative and the remaining engines operating at an appropriate power rating; and
(6) the operator has obtained prior approval for the operation from the competent authority. Before such operations take place in another Member State, the operator shall obtain an endorsement from the competent authority of that State.
(b) Site-specific procedures shall be established in the operations manual to minimise the period during which there would be danger to helicopter occupants and persons on the surface in the event of an engine failure during take-off and landing.
(c) The operations manual shall contain for each PIS: a diagram or annotated photograph, showing the main aspects, the dimensions, the non-conformance with the requirements performance class 1, the main hazards and the contingency plan should an incident occur.
[applicable until 24 May 2024 — Regulation (EU) No 965/2012]
(a) Operations to/from a public interest site (PIS) may be conducted in performance class 2, without complying with CAT.POL.H.310(b) or CAT.POL.H.325(b), provided that all of the following are complied with:
(1) the site was established as a public interest site before 1 July 2002, or the site was established as a public interest site before 28 October 2014 and a derogation from this point granted under Article 6(6) has been notified to the Commission and the Agency before 14 June, 2023;
(2) the size of the PIS or obstacle environment does not permit compliance with the requirements for operation in performance class 1;
(3) the operation is conducted with a helicopter with an MOPSC of six or less;
(4) the operator complies with CAT.POL.H.305(b)(2) and (b)(3);
(5) the helicopter mass does not exceed the maximum mass specified in the AFM for a climb gradient of 8 % in still air at the appropriate take-off safety speed (VTOSS) with the critical engine inoperative and the remaining engines operating at an appropriate power rating; and
(6) the operator has obtained prior approval for the operation from the competent authority. Before such operations take place in another Member State, the operator shall obtain an endorsement from the competent authority of that State.
(b) Site-specific procedures shall be established in the operations manual to minimise the period during which there would be danger to helicopter occupants and persons on the surface in the event of an engine failure during take-off and landing.
(c) The operations manual shall contain all the following for each PIS: a diagram or annotated photograph that shows the main aspects, the dimensions, the non-conformance with the performance class 1 requirements, the main hazards and the contingency plan should an incident occur.
(d) The operator shall keep the information provided in point (c) up to date and shall notify any changes to it to the competent authority. When operations take place in another Member State, the operator shall also notify the authority of that State.
[applicable from 25 May 2024 — Implementing Regulation (EU) 2023/1020]
AMC1 CAT.POL.H.225 Helicopter operations to/from a public interest site
ED Decision 2023/007/R
CHANGES TO THE OBSTACLE ENVIRONMENT
If the operator becomes aware of a change to the obstacle environment at an approved public interest site, the operator should:
(a) assess the safety impact of such new obstacles on their operations;
(b) review their site-specific procedures and modify them as necessary;
(c) discontinue operations at the site if necessary;
(d) inform the competent authority of all of the above.
UNDERLYING PRINCIPLES
(a) General
The original Joint Aviation Authorities (JAA) Appendix 1 to JAR-OPS 3.005(i) was introduced in January 2002 to address problems that had been encountered by Member States at hospital sites due to the applicable performance requirements of JAR-OPS 3 Subparts G and H. These problems were enumerated in ACJ to Appendix 1 to JAR-OPS 3.005(d) paragraph 8, part of which is reproduced below.
‘8 Problems with hospital sites
During implementation of JAR-OPS 3, it was established that a number of States had encountered problems with the impact of performance rules where helicopters were operated for HEMS. Although States accept that progress should be made towards operations where risks associated with a critical power unit failure are eliminated, or limited by the exposure time concept, a number of landing sites exist which do not (or never can) allow operations to performance class 1 or 2 requirements.
These sites are generally found in a congested hostile environment:
— in the grounds of hospitals; or
— on hospital buildings;
The problem of hospital sites is mainly historical and, whilst the Authority could insist that such sites not be used - or used at such a low weight that critical power unit failure performance is assured, it would seriously curtail a number of existing operations.
Even though the rule for the use of such sites in hospital grounds for HEMS operations (Appendix 1 to JAR-OPS 3.005(d) sub-paragraph (c)(2)(i)(A)) attracts alleviation until 2005, it is only partial and will still impact upon present operations.
Because such operations are performed in the public interest, it was felt that the Authority should be able to exercise its discretion so as to allow continued use of such sites provided that it is satisfied that an adequate level of safety can be maintained - notwithstanding that the site does not allow operations to performance class 1 or 2 standards. However, it is in the interest of continuing improvements in safety that the alleviation of such operations be constrained to existing sites, and for a limited period.’
As stated in this ACJ and embodied in the text of the appendix, the solution was short-term (until 31 December 2004). During the commenting period of JAA NPA 18, representations were made to the JAA that the alleviation should be extended to 2009. The review committee, in not accepting this request, had in mind that this was a short-term solution to address an immediate problem, and a permanent solution should be sought.
(b) After 1 January 2005
Although elimination of such sites would remove the problem, it is recognised that phasing out, or rebuilding existing hospital sites, is a long-term goal which may not be cost-effective, or even possible, in some Member States.
It should be noted, however, that CAT.POL.H.225(a) limits the problem by confining approvals to hospital sites established before 1 July 2002 (established in this context means either: built before that date, or brought into service before that date — this precise wording was used to avoid problems associated with a ground level aerodrome/operating site where no building would be required). Thus the problem of these sites is contained and reducing in severity. This date was set approximately 6 months after the intended implementation of the original JAR-OPS 3 appendix.
EASA adopted the JAA philosophy that, from 1st January 2005, approval would be confined to those sites where a CAT A procedure alone cannot solve the problem. The determination of whether the helicopter can or cannot be operated in accordance with performance class 1 should be established with the helicopter at a realistic payload and fuel to complete the mission. However, in order to reduce the risk at those sites, the application of the requirements contained in CAT.POL.H.225(a) should be applied.
Additionally and in order to promote understanding of the problem, the text contained in CAT.POL.H.225(c) refers to the performance class and not to ICAO Annex 14. Thus, Part C of the operations manual should reflect the non-conformance with performance class 1, as well as the site-specific procedures (approach and departure paths) to minimise the danger to third parties in the event of an incident.
The following paragraphs explain the problem and solutions.
(c) The problem associated with such sites
There is a number of problems: some of which can be solved with the use of appropriate helicopters and procedures; and others which, because of the size of the site or the obstacle environment, cannot. They consist of:
(1) the size of the surface of the site (smaller than that required by the manufacturer’s procedure);
(2) an obstacle environment that prevents the use of the manufacturer’s procedure (obstacles in the backup area); and
(3) an obstacle environment that does not allow recovery following an engine failure in the critical phase of take-off (a line of buildings requiring a demanding gradient of climb) at a realistic payload and fuel to complete the mission.
— Problems associated with (c)(1): the inability to climb and conduct a rejected landing back to the site following an engine failure before the Decision Point (DP).
— Problems associated with (c)(2): as in (c)(1)).
— Problems associated with (c)(3): climb into an obstacle following an engine failure after DP.
Problems cannot be solved in the immediate future, but can, when mitigated with the use of the latest generation of helicopters (operated at a weight that can allow useful payloads and endurance), minimise exposure to risk.
(d) Long-term solution
Although not offering a complete solution, it was felt that a significant increase in safety could be achieved by applying an additional performance margin to such operations. This solution allowed the time restriction of 2004 to be removed.
The required performance level of 8 % climb gradient in the first segment reflects ICAO Annex 14 Volume II in ‘Table 4-3 'Dimensions and slopes of obstacle limitations surfaces’ for performance class 2.
The performance delta is achieved without the provision of further manufacturer’s data by using existing graphs to provide the reduced take-off mass (RTOM).
If the solution in relation to the original problem is examined, the effects can be seen.
(1) Solution with relation to (c)(1): although the problem still exists, the safest procedure is a dynamic take-off reducing the time taken to achieve Vstayup and thus allowing VFR recovery — if the failure occurs at or after Vy and 200 ft, an IFR recovery is possible.
(2) Solution with relation to (c)(2): as in (c)(1) above.
(3) Solution with relation to (c)(3): once again this does not give a complete solution, however, the performance delta minimises the time during which a climb over the obstacle cannot be achieved.
[applicable until 24 May 2024 — ED Decision 2023/007/R]
(d) Long-term solution
(2) No mandatory phase-out is foreseen for sites approved under a derogation from CAT.POL.H.225 that were established as public interest sites before 28 October 2014.
(3) No mandatory phase-out is foreseen for sites approved under CAT.POL.H.225 that were established as public interest sites before 1 July 2002.
(4) A public interest site should be considered to be established at the time when it was operated in the public interest for the first time.
(5) As of 25 May 2024 there should be no more approvals of public interest sites that were established after 28 October 2014, in accordance with point ARO.OPS.220(c).
(6) As of 25 May 2024 the obstacle environment at approved public interest sites should be kept under continued review in order to avoid new obstacles causing a significant safety impact, in accordance with point ARO.OPS.220(d).
Table 1
Duration of public interest site approvals
|
Date on which the approved PIS was established |
Maximum duration of the PIS approval |
|
Before 28 October 2014 |
Unlimited duration, provided that there is no permanent worsening of the obstacle environment. |
|
After 28 October 2014 |
PIS approval to expire on 25 May 2028. |
(i) The performance level of 8 % climb gradient in the first segment required by point CAT.POL.H.225(a)(5) reflects ICAO Annex 14 Volume II in ‘Table 4-1 ‘Dimensions and slopes of obstacle limitations surfaces’.
(ii) The performance delta is achieved without the provision of further manufacturer’s data by using existing graphs to provide the reduced take-off mass (RTOM).
(iii) If the solution in relation to the original problem is examined, the effects can be seen.
(A) Solution with relation to (c)(1): although the problem still exists, the safest procedure is a dynamic take-off reducing the time taken to achieve Vstayup and thus allowing VFR recovery — if the failure occurs at or after Vy and 200 ft, an IFR recovery is possible.
(B) Solution with relation to (c)(2): as in (c)(1) above.
(C) Solution with relation to (c)(3): once again, this does not give a complete solution; however, the performance delta minimises the time during which a climb over the obstacle cannot be achieved.
HELICOPTER MASS LIMITATION
(a) The helicopter mass limitation at take-off or landing specified in CAT.POL.H.225(a)(5) should be determined using the climb performance data from 35 ft to 200 ft at VTOSS (first segment of the take-off flight path) contained in the Category A supplement of the AFM (or equivalent manufacturer data acceptable in accordance with GM1-CAT.POL.H.200 & CAT.POL.H.300 & CAT.POL.H.400).
(b) The first segment climb data to be considered is established for a climb at the take-off safety speed VTOSS, with the landing gear extended (when the landing gear is retractable), with the critical engine inoperative and the remaining engines operating at an appropriate power rating (the 2 min 30 sec or 2 min OEI power rating, depending on the helicopter type certification). The appropriate VTOSS, is the value specified in the Category A performance section of the AFM for vertical take-off and landing procedures (VTOL, helipad or equivalent manufacturer terminology).
(c) The ambient conditions at the site (pressure-altitude and temperature) should be taken into account.
(d) The data are usually provided in charts in one of the following ways:
(1) Height gain in ft over a horizontal distance of 100 ft in the first segment configuration (35 ft to 200 ft, VTOSS, 2 min 30 sec/2 min OEI power rating). This chart should be entered with a height gain of 8 ft per 100 ft horizontally travelled, resulting in a mass value for every pressure-altitude/temperature combination considered.
(2) Horizontal distance to climb from 35 ft to 200 ft in the first segment configuration (VTOSS, 2 min 30 sec/2 min OEI power rating). This chart should be entered with a horizontally distance of 628 m (2 062 ft), resulting in a mass value for every pressure-altitude/temperature combination considered.
(3) Rate of climb in the first segment configuration (35 ft to 200 ft, VTOSS, 2 min 30 sec/2 min OEI power rating). This chart can be entered with a rate of climb equal to the climb speed (VTOSS) value in knots (converted to true airspeed) multiplied by 8.1, resulting in a mass value for every pressure-altitude/temperature combination considered.
ENDORSEMENT FROM ANOTHER STATE
(a) Application to another State
To obtain an endorsement from another State, the operator should submit to that State:
(1) the reasons that preclude compliance with the requirements for operations in performance class 1;
(2) the site-specific procedures to minimise the period during which there would be danger to helicopter occupants and person on the surface in the event of an engine failure during take-off and landing; and
(3) the extract from the operations manual to comply with CAT.POL.H.225(c).
(b) Endorsement from another State
Upon receiving the endorsement from another State, the operator should submit it together with the site-specific procedures and the reasons and justification that preclude the use of performance class 1 criteria to the competent authority issuing the AOC to obtain the approval or extend the approval to a new public interest site.
CHAPTER 3 – Performance class 2
Regulation (EU) No 965/2012
Helicopters operated in performance class 2 shall be certified in category A or equivalent as determined by the Agency.
OPERATIONS IN PERFORMANCE CLASS 2
(a) Introduction
This GM describes performance class 2 as established in Part-CAT. It has been produced for the purpose of:
(1) explaining the underlying philosophy of operations in performance class 2;
(2) showing simple means of compliance; and
(3) explaining how to determine — with examples and diagrams:
(i) the take-off and landing masses;
(ii) the length of the safe forced landing area;
(iii) distances to establish obstacle clearance; and
(iv) entry point(s) into performance class 1.
It explains the derivation of performance class 2 from ICAO Annex 6 Part III and describes an alleviation that may be approved in accordance with CAT.POL.H.305 following a risk assessment.
It examines the basic requirements, discusses the limits of operation, and considers the benefits of the use of performance class 2.
It contains examples of performance class 2 in specific circumstances, and explains how these examples may be generalised to provide operators with methods of calculating landing distances and obstacle clearance.
(b) Definitions used in this GM
The definitions for the following terms, used in this GM, are contained in Annex I and its AMC:
(1) distance DR;
(2) defined point after take-off (DPATO);
(3) defined point before landing (DPBL);
(4) landing distance available (LDAH);
(5) landing distance required (LDRH);
(6) performance class 2;
(7) safe forced landing (SFL); and
(8) take-off distance available (TODAH).
The following terms, which are not defined Annex I, are used in this GM:
— VT : a target speed at which to aim at the point of minimum ground clearance (min-dip) during acceleration from TDP to VTOSS;
— V50. : a target speed and height utilised to establish an AFM distance (in compliance with the requirement of CS/JAR 29.63) from which climb out is possible; and
— Vstayup : a colloquial term used to indicate a speed at which a descent would not result following an engine failure. This speed is several knots lower than VTOSS at the equivalent take-off mass.
(c) What defines performance class 2
Performance class 2 can be considered as performance class 3 take-off or landing, and performance class 1 climb, cruise and descent. It comprises an all-engines-operating (AEO) obstacle clearance regime for the take-off or landing phases, and a OEI obstacle clearance regime for the climb, cruise, descent, approach and missed approach phases.
For the purpose of performance calculations in Part-CAT, the CS/JAR 29.67 Category A climb performance criteria is used:
— 150 ft/min at 1 000 ft (at Vy);
and depending on the choice of DPATO:
— 100 ft/min up to 200 ft (at VTOSS)
at the appropriate power settings.
(1) Comparison of obstacle clearance in all performance classes
Figure 1 shows the profiles of the three performance classes — superimposed on one diagram.
— Performance class 1 (PC1): from TDP, requires OEI obstacle clearance in all phases of flight; the construction of Category A procedures, provides for a flight path to the first climb segment, a level acceleration segment to Vy (which may be shown concurrent with the first segment), followed by the second climb segment from Vy at 200 ft (see Figure 1).
Figure 1
All Performance Classes (a comparison)
— Performance class 2 (PC2): requires AEO obstacle clearance to DPATO and OEI from then on. The take-off mass has the PC1 second segment climb performance at its basis therefore, at the point where Vy at 200 ft is reached, Performance Class 1 is achieved (see also Figure 3).
— Performance class 3 (PC3): requires AEO obstacle clearance in all phases.
Figure 2
Performance Class 1 distances
(2) Comparison of the discontinued take-off in all performance classes
(i) PC1 — requires a prepared surface on which a rejected landing can be undertaken (no damage); and
(ii) PC2 and 3 — require a safe forced landing surface (some damage can be tolerated, but there must be a reasonable expectancy of no injuries to persons in the aircraft or third parties on the surface).
(d) The derivation of performance class 2
PC2 is primarily based on the text of ICAO Annex 6 Part III Section II and its attachments which provide for the following:
(1) obstacle clearance before DPATO: the helicopter shall be able, with all engines operating, to clear all obstacles by an adequate margin until it is in a position to comply with (2);
(2) obstacle clearance after DPATO: the helicopter shall be able, in the event of the critical engine becoming inoperative at any time after reaching DPATO, to continue the take-off clearing all obstacles along the flight path by an adequate margin until it is able to comply with en-route clearances; and
(3) engine failure before DPATO: before the DPATO, failure of the critical engine may cause the helicopter to force land; therefore, a safe forced landing should be possible (this is analogous to the requirement for a reject in performance class 1, but where some damage to the helicopter can be tolerated.)
(e) Benefits of performance class 2
Operations in performance class 2 permit advantage to be taken of an AEO procedure for a short period during take-off and landing — whilst retaining engine failure accountability in the climb, descent and cruise. The benefits include the ability to:
(1) use (the reduced) distances scheduled for the AEO — thus permitting operations to take place at smaller aerodromes and allowing airspace requirements to be reduced;
(2) operate when the safe forced landing distance available is located outside the boundary of the aerodrome;
(3) operate when the take-off distance required is located outside the boundary of the aerodrome; and
(4) use existing Category A profiles and distances when the surface conditions are not adequate for a reject, but are suitable for a safe forced landing (for example, when the ground is waterlogged).
Additionally, following a risk assessment when the use of exposure is approved by the competent authority the ability to:
(i) operate when a safe forced landing is not assured in the take-off phase; and
(ii) penetrate the HV curve for short periods during take-off or landing.
(f) Implementation of performance class 2 in Part-CAT
The following sections explain the principles of the implementation of performance class 2.
(1) Does ICAO spell it all out?
ICAO Annex 6 does not give guidance on how DPATO should be calculated nor does it require that distances be established for the take-off. However, it does require that, up to DPATO AEO, and from DPATO OEI, obstacle clearance is established (see Figure 3 and Figure 4 which are simplified versions of the diagrams contained in Annex 6 Part III, Attachment A).
(ICAO Annex 8 – Airworthiness of Aircraft (IVA 2.2.3.1.4’ and ‘IVB 2.2.7 d) requires that an AEO distance be scheduled for all helicopters operating in performance classes 2 & 3. ICAO Annex 6 is dependent upon the scheduling of the AEO distances, required in Annex 8, to provide data for the location of DPATO.)
When showing obstacle clearance, the divergent obstacle clearance height required for IFR is — as in performance class 1 — achieved by the application of the additional obstacle clearance of 0.01 distance DR (the distance from the end of ‘take-off-distance-available’ — see the pictorial representation in Figure 4 and the definition in Annex I).
As can also be seen from Figure 4, flight must be conducted in VFR until DPATO has been achieved (and deduced that if an engine failure occurs before DPATO, entry into IFR is not permitted (as the OEI climb gradient will not have been established)).
Figure 3
Performance Class 2 Obstacle Clearance
Figure 4
Performance Class 2 Obstacle Clearance (plan view)
(2) Function of DPATO
From the preceding paragraphs, it can be seen that DPATO is germane to PC2. It can also be seen that, in view of the many aspects of DPATO, it has, potentially, to satisfy a number of requirements that are not necessarily synchronised (nor need to be).
It is clear that it is only possible to establish a single point for DPATO, satisfying the requirement of (d)(2) & (d)(3), when:
— accepting the TDP of a Category A procedure; or
— extending the safe forced landing requirement beyond required distances (if data are available to permit the calculation of the distance for a safe forced landing from the DPATO).
It could be argued that the essential requirement for DPATO is contained in section (d)(2) — OEI obstacle clearance. From careful examination of the flight path reproduced in Figure 3 above, it may be reasonably deduced that DPATO is the point at which adequate climb performance is established (examination of Category A procedures would indicate that this could be (in terms of mass, speed and height above the take-off surface) the conditions at the start of the first or second segments — or any point between.)
(The diagrams in Attachment A of ICAO Annex 6 do not appear to take account of drop down — permitted under Category A procedures; similarly with helideck departures, the potential for acceleration in drop down below deck level (once the deck edge has been cleared) is also not shown. These omissions could be regarded as a simplification of the diagram, as drop down is discussed and accepted in the accompanying ICAO text.)
It may reasonably be argued that, during the take-off and before reaching an appropriate climb speed (VTOSS or Vy), Vstayup will already have been achieved (where Vstayup is the ability to continue the flight and accelerate without descent — shown in some Category A procedures as VT or target speed) and where, in the event of an engine failure, no landing would be required.
It is postulated that, to practically satisfy all the requirements of (d)(1), (2) and (3), DPATO does not need to be defined at one synchronised point; provisions can be met separately, i.e. defining the distance for a safe forced landing, and then establishing the OEI obstacle clearance flight path.
As the point at which the helicopter’s ability to continue the flight safely, with the critical engine inoperative is the critical element, it is that for which DPATO is used in this text.
Figure 5
The three elements in a PC 2 take-off
(i) The three elements from the pilot’s perspective
When seen from the pilot’s perspective (see Figure 5), there are three elements of the PC 2 take-off — each with associated related actions which need to be considered in the case of an engine failure:
(A) action in the event of an engine failure — up to the point where a forced-landing will be required;
(B) action in the event of an engine failure — from the point where OEI obstacle clearance is established (DPATO); and
(C) pre-considered action in the event of an engine failure — in the period between (A) and (B)
The action of the pilot in (A) and (B) is deterministic, i.e. it remains the same for every occasion. For pre-consideration of the action at point (C), as is likely that the planned flight path will have to be abandoned (the point at which obstacle clearance using the OEI climb gradients not yet being reached), the pilot must (before take-off) have considered his/her options and the associated risks, and have in mind the course of action that will be pursued in the event of an engine failure during that short period. (As it is likely that any action will involve turning manoeuvres, the effect of turns on performance must be considered.)
(3) Take-off mass for performance class 2
As previously stated, performance class 2 is an AEO take-off that, from DPATO, has to meet the requirement for OEI obstacle clearance in the climb and en-route phases. Take-off mass is, therefore, the mass that gives at least the minimum climb performance of 150 ft/min at Vy, at 1 000 ft above the take-off point, and obstacle clearance.
As can be seen in Figure 6 below, the take-off mass may have to be modified when it does not provide the required OEI clearance from obstacles in the take-off-flight path (exactly as in performance class 1). This could occur when taking off from an aerodrome/operating site where the flight path has to clear an obstacle such a ridge line (or line of buildings) that can neither be:
(i) flown around using VFR and see and avoid; nor
(ii) cleared using the minimum climb gradient given by the take-off mass (150 ft/min at 1 000 ft).
In this case, the take-off mass has to be modified (using data contained in the AFM) to give an appropriate climb gradient.
Figure 6
Performance Class 2 (enhanced climb gradient)
(4) Do distances have to be calculated?
Distances do not have to be calculated if, by using pilot judgement or standard practice, it can be established that:
(i) a safe forced landing is possible following an engine failure (notwithstanding that there might be obstacles in the take-off path); and
(ii) obstacles can be cleared (or avoided) — AEO in the take-off phase and OEI in the climb.
If early entry (in the sense of cloud base) into IMC is expected, an IFR departure should be planned. However, standard masses and departures can be used when described in the operations manual.
(5) The use of Category A data
In Category A procedures, TDP is the point at which either a rejected landing or a safe continuation of the flight, with OEI obstacle clearance, can be performed.
For PC2 (when using Category A data), only the safe forced landing (reject) distance depends on the equivalent of the TDP; if an engine fails between TDP and DPATO, the pilot has to decide what action is required. It is not necessary for a safe forced landing distance to be established from beyond the equivalent of TDP (see Figure 5 and discussion in (f)(2)(ii)(A)).
Category A procedures based on a fixed VTOSS are usually optimised either for the reduction of the rejected take-off distance, or the take-off distance. Category A procedures based on a variable VTOSS allow either a reduction in required distances (low VTOSS) or an improvement in OEI climb capability (high VTOSS). These optimisations may be beneficial in PC2 to satisfy the dimensions of the take-off site.
In view of the different requirements for PC2 (from PC1), it is perfectly acceptable for the two calculations (one to establish the safe forced landing distance and the other to establish DPATO) to be based upon different Category A procedures. However, if this method is used, the mass resulting from the calculation cannot be more than the mass from the more limiting of the procedures.
(6) DPATO and obstacle clearance
If it is necessary for OEI obstacle clearance to be established in the climb, the starting point (DPATO) for the (obstacle clearance) gradient has to be established. Once DPATO is defined, the OEI obstacle clearance is relatively easy to calculate with data from the AFM.
(i) DPATO based on AEO distance
In the simplest case; if provided, the scheduled AEO to 200 ft at Vy can be used (see Figure 7).
Figure 7
Suggested AEO locations for DPATO
Otherwise, and if scheduled in the AFM, the AEO distance to 50 ft (V50) — determined in accordance with CS/JAR 29.63 — can be used (see Figure 7). Where this distance is used, it will be necessary to ensure that the V50 climb out speed is associated with a speed and mass for which OEI climb data are available so that, from V50, the OEI flight path can be constructed.
(ii) DPATO based on Category A distances
It is not necessary for specific AEO distances to be used (although for obvious reasons it is preferable); if they are not available, a flight path (with OEI obstacle clearance) can be established using Category A distances (see Figure 8 and Figure 9) — which will then be conservative.
Figure 8
Using Cat A data; actual and apparent position of DPATO (Vtoss and start of first segment)
The apparent DPATO is for planning purposes only in the case where AEO data are not available to construct the take-off flight path. The actual OEI flight path will provide better obstacle clearance than the apparent one (used to demonstrate the minimum requirement) — as seen from the firm and dashed lines in the above figure.
Figure 9
Using Cat A data; actual and apparent position of DPATO (Vy and start of second segment)
(iii) Use of most favourable Category A data
The use of AEO data are recommended for calculating DPATO. However, where an AEO distance is not provided in the flight manual, distance to Vy at 200 ft, from the most favourable of the Category A procedures, can be used to construct a flight path (provided it can be demonstrated that AEO distance to 200 ft at Vy is always closer to the take-off point than the CAT A OEI flight path).
In order to satisfy the requirement of CAT.POL.H.315, the last point from where the start of OEI obstacle clearance can be shown is at 200 ft.
(7) The calculation of DPATO — a summary
DPATO should be defined in terms of speed and height above the take-off surface and should be selected such that AFM data (or equivalent data) are available to establish the distance from the start of the take-off up to the DPATO (conservatively if necessary).
(i) First method
DPATO is selected as the AFM Category B take-off distance (V50 speed or any other take-off distance scheduled in accordance with CS/JAR 29.63) provided that within the distance the helicopter can achieve:
(A) one of the VTOSS values (or the unique VTOSS value if it is not variable) provided in the AFM, selected so as to assure a climb capability according to Category A criteria; or
(B) Vy.
Compliance with CAT.POL.H.315 would be shown from V50 (or the scheduled Category B take-off distance).
(ii) Second method
DPATO is selected as equivalent to the TDP of a Category A ‘clear area’ take-off procedure conducted in the same conditions.
Compliance with CAT.POL.H.315 would be shown from the point at which VTOSS, a height of at least 35 ft above the take-off surface and a positive climb gradient are achieved (which is the Category A ‘clear area’ take-off distance).
Safe forced landing areas should be available from the start of the take-off, to a distance equal to the Category A ‘clear area’ rejected take-off distance.
(iii) Third method
As an alternative, DPATO could be selected such that AFM OEI data are available to establish a flight path initiated with a climb at that speed. This speed should then be:
(A) one of the VTOSS values (or the unique VTOSS value if it is not variable) provided in the AFM, selected so as to assure a climb capability according to Category A criteria; or
(B) Vy
The height of the DPATO should be at least 35 ft and can be selected up to 200 ft. Compliance with CAT.POL.H.315 would be shown from the selected height.
(8) Safe forced landing distance
Except as provided in (f)(7)(ii), the establishment of the safe forced landing distance could be problematical as it is not likely that PC2 specific data will be available in the AFM.
By definition, the Category A reject distance may be used when the surface is not suitable for a reject, but may be satisfactory for a safe forced landing (for example, where the surface is flooded or is covered with vegetation).
Any Category A (or other accepted) data may be used to establish the distance. However, once established, it remains valid only if the Category A mass (or the mass from the accepted data) is used and the Category A (or accepted) AEO profile to the TDP is flown. In view of these constraints, the likeliest Category A procedures are the clear area or the short field (restricted area/site) procedures.
From Figure 10, it can be seen that if the Category B V50 procedure is used to establish DPATO, the combination of the distance to 50 ft and the Category A ‘clear area’ landing distance, required by CS/JAR 29.81 (the horizontal distance required to land and come to a complete stop from a point 50 ft above the landing surface), will give a good indication of the maximum safe-forced-landing distance required (see also the explanation on Vstayup above).
Figure 10
Category B (V50) safe–forced–landing distance
(9) Performance class 2 landing
For other than PC2 operations to elevated FATOs or helidecks (see section (g)(4)(i)), the principles for the landing case are much simpler. As the performance requirements for PC1 and PC2 landings are virtually identical, the condition of the landing surface is the main issue.
If the engine fails at any time during the approach, the helicopter must be able either: to perform a go-around meeting the requirements of CAT.POL.H.315; or perform a safe forced landing on the surface. In view of this, and if using PC1 data, the LDP should not be lower that the corresponding TDP (particularly in the case of a variable TDP).
The landing mass will be identical to the take-off mass for the same site (with consideration for any reduction due to obstacle clearance — as shown in Figure 6 above).
In the case of a balked landing (i.e. the landing site becomes blocked or unavailable during the approach), the full requirement for take-off obstacle clearance must be met.
(g) Operations in performance class 2 with exposure
The Implementing Rules offer an opportunity to discount the requirement for an assured safe forced landing area in the take-off or landing phase — subject to an approval from the competent authority. The following sections deals with this option:
(1) Limit of exposure
As stated above, performance class 2 has to ensure AEO obstacle clearance to DPATO and OEI obstacle clearance from that point. This does not change with the application of exposure.
It can, therefore, be stated that operations with exposure are concerned only with alleviation from the requirement for the provision of a safe forced landing.
The absolute limit of exposure is 200 ft — from which point OEI obstacle clearance must be shown.
(2) The principle of risk assessment
ICAO Annex 6 Part III Chapter 3.1.2 states that:
‘3.1.2 In conditions where the safe continuation of flight is not ensured in the event of a critical engine failure, helicopter operations shall be conducted in a manner that gives appropriate consideration for achieving a safe forced landing.’
Although a safe forced landing may no longer be the (absolute) Standard, it is considered that risk assessment is obligatory to satisfy the amended requirement for ‘appropriate consideration’.
Risk assessment used for fulfilment of this proposed Standard is consistent with principles described in ‘AS/NZS 4360:1999’. Terms used in this text and defined in the AS/NZS Standard are shown in Sentence Case e.g. risk assessment or risk reduction.
(3) The application of risk assessment to performance class 2
Under circumstances where no risk attributable to engine failure (beyond that inherent in the safe forced landing) is present, operations in performance class 2 may be conducted in accordance with the non-alleviated requirements contained above — and a safe forced landing will be possible.
Under circumstances where such risk would be present, i.e. operations to an elevated FATO (deck edge strike); or, when permitted, operations from a site where a safe forced landing cannot be accomplished because the surface is inadequate; or where there is penetration into the HV curve for a short period during take-off or landing (a limitation in CS/JAR 29 AFMs), operations have to be conducted under a specific approval.
Provided such operations are risk assessed and can be conducted to an established safety target, they may be approved in accordance with CAT.POL.H.305.
(i) The elements of the risk management
The approval process consists of an operational risk assessment and the application of four principles:
(A) a safety target;
(B) a helicopter reliability assessment;
(C) continuing airworthiness; and
(D) mitigating procedures.
(ii) The safety target
The main element of the risk assessment when exposure was initially introduced by the JAA into JAR-OPS 3 (NPA OPS-8), was the assumption that turbine engines in helicopters would have failure rates of about 1:100 000 per flying hour, which would permit (against the agreed safety target of 5 x 10-8 per event) an exposure of about 9 seconds for twins during the take-off or landing event. (When choosing this target it was assumed that the majority of current well-maintained turbine powered helicopters would be capable of meeting the event target — it, therefore, represents the residual risk).
(Residual risk is considered to be the risk that remains when all mitigating procedures — airworthiness and operational — are applied (see sections (g)(3)(iv) and (g)(3)(v))).
(iii) The reliability assessment
The reliability assessment was initiated to test the hypothesis (stated in (g)(3)(ii) ) that the majority of turbine powered types would be able to meet the safety target. This hypothesis could only be confirmed by an examination of the manufacturers’ power-loss data.
(iv) Mitigating procedures (airworthiness)
Mitigating procedures consist of a number of elements:
(A) the fulfilment of all manufacturers’ safety modifications;
(B) a comprehensive reporting system (both failures and usage data); and
(C) the implementation of a usage monitoring system (UMS).
Each of these elements is to ensure that engines, once shown to be sufficiently reliable to meet the safety target, will sustain such reliability (or improve upon it).
The monitoring system is felt to be particularly important as it had already been demonstrated that when such systems are in place it inculcates a more considered approach to operations. In addition, the elimination of ‘hot starts’, prevented by the UMS, itself minimises the incidents of turbine burst failures.
(v) Mitigating procedures (operations)
Operational and training procedures, to mitigate the risk — or minimise the consequences — are required of the operator. Such procedures are intended to minimise risk by ensuring that:
(A) the helicopter is operated within the exposed region for the minimum time; and
(B) simple but effective procedures are followed to minimise the consequence should an engine failure occur.
(4) Operation with exposure
When operating with exposure, there is alleviation from the requirement to establish a safe forced landing area (which extends to landing as well as take-off). However, the requirement for obstacle clearance — AEO in the take-off and from DPATO OEI in the climb and en-route phases — remains (both for take-off and landing).
The take-off mass is obtained from the more limiting of the following:
— the climb performance of 150 ft/min at 1 000 ft above the take-off point; or
— obstacle clearance (in accordance with (f)(3) above); or
— AEO hover out of ground effect (HOGE) performance at the appropriate power setting. (AEO HOGE is required to ensure acceleration when (near) vertical dynamic take-off techniques are being used. Additionally, for elevated FATO or helidecks, it ensures a power reserve to offset ground cushion dissipation; and ensures that, during the landing manoeuvre, a stabilised HOGE is available — should it be required.)
(i) Operations to elevated FATOs or helidecks
PC2 operations to elevated FATOs and helidecks are a specific case of operations with exposure. In these operations, the alleviation covers the possibility of:
(A) a deck-edge strike if the engine fails early in the take-off or late in the landing;
(B) penetration into the HV Curve during take-off and landing; and
(C) forced landing with obstacles on the surface (hostile water conditions) below the elevated FATO (helideck). The take-of mass is as stated above and relevant techniques are as described in GM1 CAT.POL.H.310(c) & CAT.POL.H.325(c).
It is unlikely that the DPATO will have to be calculated with operations to helidecks (due to the absence of obstacles in the take-off path).
(ii) Additional requirements for operations to helidecks in a hostile environment
For a number of reasons (e.g. the deck size, and the helideck environment — including obstacles and wind vectors), it was not anticipated that operations in PC1 would be technically feasible or economically justifiable by the projected JAA deadline of 2010 (OEI HOGE could have provided a method of compliance, but this would have resulted in a severe and unwarranted restriction on payload/range).
However, due to the severe consequences of an engine failure to helicopters involved in take-off and landings to helidecks located in hostile sea areas (such as the North Sea or the North Atlantic), a policy of risk reduction is called for. As a result, enhanced class 2 take-off and landing masses together with techniques that provide a high confidence of safety due to:
(A) deck-edge avoidance; and
(B) drop-down that provides continued flight clear of the sea,
are seen as practical measures.
For helicopters which have a Category A elevated helideck procedure, certification is satisfied by demonstrating a procedure and adjusted masses (adjusted for wind as well as temperature and pressure) that assure a 15-ft deck edge clearance on take-off and landing. It is, therefore, recommended that manufacturers, when providing enhanced PC2 procedures, use the provision of this deck-edge clearance as their benchmark.
As the height of the helideck above the sea is a variable, drop down has to be calculated; once clear of the helideck, a helicopter operating in PC1 would be expected to meet the 35-ft obstacle clearance. Under circumstances other than open sea areas and with less complex environmental conditions, this would not present difficulties. As the provision of drop down takes no account of operational circumstances, standard drop down graphs for enhanced PC2 — similar to those in existence for Category A procedures — are anticipated.
Under conditions of offshore operations, calculation of drop down is not a trivial matter — the following examples indicate some of the problems which might be encountered in hostile environments:
(A) Occasions when tide is not taken into account and the sea is running irregularly — the level of the obstacle (i.e. the sea) is indefinable making a true calculation of drop down impossible.
(B) Occasions when it would not be possible — for operational reasons — for the approach and departure paths to be clear of obstacles — the ‘standard’ calculation of drop-down could not be applied.
Under these circumstances, practicality indicates that drop down should be based upon the height of the deck AMSL and the 35-ft clearance should be applied.
There are, however, other and more complex issues which will also affect the deck-edge clearance and drop down calculations.
(C) When operating to moving decks on vessels, a recommended landing or take-off profile might not be possible because the helicopter might have to hover alongside in order that the rise and fall of the ship is mentally mapped; or, on take-off re-landing in the case of an engine failure might not be an option.
Under these circumstances, the commander might adjust the profiles to address a hazard more serious or more likely than that presented by an engine failure.
It is because of these and other (unforeseen) circumstances that a prescriptive requirement is not used. However, the target remains a 15-ft deck-edge clearance and a 35-ft obstacle clearance and data should be provided such that, where practically possible, these clearances can be planned.
As accident/incident history indicates that the main hazard is collision with obstacles on the helideck due to human error, simple and reproducible take-off and landing procedures are recommended.
In view of the reasons stated above, the future requirement for PC1 was replaced by the new requirement that the take-off mass takes into account:
— the procedure;
— deck-edge miss; and
— drop down appropriate to the height of the helideck.
This will require calculation of take-off mass from information produced by manufacturers reflecting these elements. It is expected that such information will be produced by performance modelling/simulation using a model validated through limited flight testing.
(iii) Operations to helidecks for helicopters with a maximum operational passenger seating configuration (MOPSC) of more than 19
The original requirement for operations of helicopters with an MOPSC of more than 19 was PC1 (as set out in CAT.POL.H.100(b)(2)).
However, when operating to helidecks, the problems enumerated in (g)(4)(ii) above are equally applicable to these helicopters. In view of this, but taking into account that increased numbers are (potentially) being carried, such operations are permitted in PC2 (CAT.POL.H.100(b)(2)) but, in all helideck environments (both hostile and non-hostile), have to satisfy, the additional requirements, set out in (g)(4)(ii) above.
CAT.POL.H.305 Operations without an assured safe forced landing capability
Regulation (EU) No 965/2012
(a) Operations without an assured safe forced landing capability during the take-off and landing phases shall only be conducted if the operator has been granted an approval by the competent authority.
(b) To obtain and maintain such approval the operator shall:
(1) conduct a risk assessment, specifying:
(i) the type of helicopter; and
(ii) the type of operations;
(2) implement the following set of conditions:
(i) attain and maintain the helicopter/engine modification standard defined by the manufacturer;
(ii) conduct the preventive maintenance actions recommended by the helicopter or engine manufacturer;
(iii) include take-off and landing procedures in the operations manual, where they do not already exist in the AFM;
(iv) specify training for flight crew; and
(v) provide a system for reporting to the manufacturer loss of power, engine shutdown or engine failure events;
and
(3) implement a usage monitoring system (UMS).
VALIDITY OF THE RISK ASSESSMENT
The operator should periodically review and update the procedures and associated risk assessments, pertaining to the granting of the CAT.POL.H.305(a) approval, to ensure that they are adequate and remain relevant for the operation.
ENGINE RELIABILITY STATISTICS
(a) As part of the risk assessment prior to granting an approval under CAT.POL.H.305, the operator should provide appropriate engine reliability statistics available for the helicopter type and the engine type.
(b) Except in the case of new engines, such data should show sudden power loss from the set of in-flight shutdown (IFSD) events not exceeding 1 per 100 000 engine hours in a 5 year moving window. However, a rate in excess of this value, but not exceeding 3 per 100 000 engine hours, may be accepted by the competent authority after an assessment showing an improving trend.
(c) New engines should be assessed on a case-by-case basis.
(d) After the initial assessment, updated statistics should be periodically reassessed; any adverse sustained trend will require an immediate evaluation to be accomplished by the operator in consultation with the competent authority and the manufacturers concerned. The evaluation may result in corrective action or operational restrictions being applied.
(e) The purpose of this paragraph is to provide guidance on how the in-service power plant sudden power loss rate is determined.
(1) Share of roles between the helicopter and engine type certificate holders (TCH)
(i) The provision of documents establishing the in-service sudden power loss rate for the helicopter/engine installation; the interface with the operational authority of the State of the operator should be the engine TCH or the helicopter TCH depending on the way they share the corresponding analysis work.
(ii) The engine TCH should provide the helicopter TCH with a document including: the list of in-service power loss events, the applicability factor for each event (if used), and the assumptions made on the efficiency of any corrective actions implemented (if used).
(iii) The engine or helicopter TCH should provide the operational authority of the State of the operator, with a document that details the calculation results taking into account the following:
(A) events caused by the engine and the events caused by the engine installation;
(B) applicability factor for each event (if used), the assumptions made on the efficiency of any corrective actions implemented on the engine and on the helicopter (if used); and
(C) calculation of the power plant power loss rate.
(2) Documentation
The following documentation should be updated every year:
(i) the document with detailed methodology and calculation as distributed to the authority of the State of design;
(ii) a summary document with results of computation as made available on request to any operational authority; and
(iii) a service letter establishing the eligibility for such operation and defining the corresponding required configuration as provided to the operators.
(3) Definition of ‘sudden in-service power loss’
Sudden in-service power loss is an engine power loss:
(i) larger than 30 % of the take-off power;
(ii) occurring during operation; and
(iii) without the occurrence of an early intelligible warning to inform and give sufficient time for the pilot to take any appropriate action.
(4) Database documentation
Each power loss event should be documented, by the engine and/or helicopter TCHs, as follows:
(i) incident report number;
(ii) engine type;
(iii) engine serial number;
(iv) helicopter serial number;
(v) date;
(vi) event type (demanded IFSD, un-demanded IFSD);
(vii) presumed cause;
(viii) applicability factor when used; and
(ix) reference and assumed efficiency of the corrective actions that will have to be applied (if any).
(5) Counting methodology
Various methodologies for counting engine power loss rate have been accepted by authorities. The following is an example of one of these methodologies.
(i) The events resulting from:
(A) unknown causes (wreckage not found or totally destroyed, undocumented or unproven statements);
(B) where the engine or the elements of the engine installation have not been investigated (for example, when the engine has not been returned by the customer); or
(C) an unsuitable or non-representative use (operation or maintenance) of the helicopter or the engine,
are not counted as engine in-service sudden power loss and the applicability factor is 0 %.
(ii) The events caused by:
(A) the engine or the engine installation; or
(B) the engine or helicopter maintenance, when the applied maintenance was compliant with the maintenance manuals,
are counted as engine in-service sudden power loss and the applicability factor is 100 %.
(iii) For the events where the engine or an element of the engine installation has been submitted for investigation, but where this investigation subsequently failed to define a presumed cause, the applicability factor is 50 %.
(6) Efficiency of corrective actions
The corrective actions made by the engine and helicopter manufacturers on the definition or maintenance of the engine or its installation may be defined as mandatory for specific operations. In this case, the associated reliability improvement may be considered as a mitigating factor for the event.
A factor defining the efficiency of the corrective action may be applied to the applicability factor of the concerned event.
(7) Method of calculation of the power plant power loss rate
The detailed method of calculation of the power plant power loss rate should be documented by engine or helicopter TCH and accepted by the relevant authority.
IMPLEMENTATION OF THE SET OF CONDITIONS
To obtain an approval under CAT.POL.H.305(a), the operator conducting operations without an assured safe forced landing capability should implement the following:
(a) Attain and then maintain the helicopter/engine modification standard defined by the manufacturer that has been designated to enhance reliability during the take-off and landing phases.
(b) Conduct the preventive maintenance actions recommended by the helicopter or engine manufacturer as follows:
(1) engine oil spectrometric and debris analysis — as appropriate;
(2) engine trend monitoring, based on available power assurance checks;
(3) engine vibration analysis (plus any other vibration monitoring systems where fitted); and
(4) oil consumption monitoring.
(c) The usage monitoring system should fulfil at least the following:
(1) Recording of the following data:
(i) date and time of recording, or a reliable means of establishing these parameters;
(ii) amount of flight hours recorded during the day plus total flight time;
(iii) N1 (gas producer RPM) cycle count;
(iv) N2 (power turbine RPM) cycle count (if the engine features a free turbine);
(v) turbine temperature exceedance: value, duration;
(vi) power-shaft torque exceedance: value, duration (if a torque sensor is fitted);
(vii) engine shafts speed exceedance: value, duration.
(2) Data storage of the above parameters, if applicable, covering the maximum flight time in a day, and not less than 5 flight hours, with an appropriate sampling interval for each parameter.
(3) The system should include a comprehensive self-test function with a malfunction indicator and a detection of power-off or sensor input disconnection.
(4) A means should be available for downloading and analysis of the recorded parameters. Frequency of downloading should be sufficient to ensure data are not lost through overwriting.
(5) The analysis of parameters gathered by the usage monitoring system, the frequency of such analysis and subsequent maintenance actions should be described in the maintenance documentation.
(6) The data should be stored in an acceptable form and accessible to the competent authority for at least 24 months.
(d) The training for flight crew should include the discussion, demonstration, use and practice of the techniques necessary to minimise the risks.
(e) Report to the manufacturer any loss of power control, engine shutdown (precautionary or otherwise) or engine failure for any cause (excluding simulation of engine failure during training). The content of each report should provide:
(1) date and time;
(2) operator (and maintenance organisations where relevant);
(3) type of helicopter and description of operations;
(4) registration and serial number of airframe;
(5) engine type and serial number;
(6) power unit modification standard where relevant to failure;
(7) engine position;
(8) symptoms leading up to the event;
(9) circumstances of engine failure including phase of flight or ground operation;
(10) consequences of the event;
(11) weather/environmental conditions;
(12) reason for engine failure — if known;
(13) in case of an in-flight shutdown (IFSD), nature of the IFSD (demanded/un-demanded);
(14) procedure applied and any comment regarding engine restart potential;
(15) engine hours and cycles (from new and last overhaul);
(16) airframe flight hours;
(17) rectification actions applied including, if any, component changes with part number and serial number of the removed equipment; and
(18) any other relevant information.
USE OF FULL AUTHORITY DIGITAL ENGINE CONTROL (FADEC)
Current technology increasingly allows for the recording function required in (c)(1) of AMC2 CAT.POL.H.305(b) to be incorporated in the full authority digital engine control (FADEC).
Where a FADEC is capable of recording some of the parameters required by (c)(1) of AMC2 CAT.POL.H.305(b), it is not intended that the recording of the parameters is to be duplicated.
Providing that the functions as set out in (c) of AMC2 CAT.POL.H.305(b) are satisfied, the FADEC may partially, or in whole, fulfil the requirement for recording and storing parameters in a usage monitoring system.
Regulation (EU) No 965/2012
(a) The take-off mass shall not exceed the maximum mass specified for a rate of climb of 150 ft/min at 300 m (1 000 ft) above the level of the aerodrome or operating site with the critical engine inoperative and the remaining engine(s) operating at an appropriate power rating.
(b) For operations other than those specified in CAT.POL.H.305, the take-off shall be conducted such that a safe forced landing can be executed until the point where safe continuation of the flight is possible.
(c) For operations in accordance with CAT.POL.H.305, in addition to the requirements of (a):
(1) the take-off mass shall not exceed the maximum mass specified in the AFM for an all engines operative out of ground effect (AEO OGE) hover in still air with all engines operating at an appropriate power rating; or
(2) for operations from a helideck:
(i) with a helicopter that has an MOPSC of more than 19; or
(ii) any helicopter operated from a helideck located in a hostile environment,
the take-off mass shall take into account: the procedure; deck-edge miss and drop down appropriate to the height of the helideck with the critical engine(s) inoperative and the remaining engines operating at an appropriate power rating.
(d) When showing compliance with (a) to (c), account shall be taken of the appropriate parameters of CAT.POL.H.105(c) at the point of departure.
(e) That part of the take-off before the requirement of CAT.POL.H.315 is met shall be conducted in sight of the surface.
PROCEDURE FOR CONTINUED OPERATIONS TO HELIDECKS
(a) Factors to be considered when taking off from or landing on a helideck
(1) In order to take account of the considerable number of variables associated with the helideck environment, each take-off and landing may require a slightly different profile. Factors such as helicopter mass and centre of gravity, wind velocity, turbulence, deck size, deck elevation and orientation, obstructions, power margins, platform gas turbine exhaust plumes etc., will influence both the take-off and landing. In particular, for the landing, additional considerations such as the need for a clear go-around flight path, visibility and cloud base, etc. will affect the commander’s decision on the choice of landing profile. Profiles may be modified, taking account of the relevant factors noted above and the characteristics of individual helicopter types.
(b) Performance
(1) To perform the following take-off and landing profiles, adequate all engines operating (AEO) hover performance at the helideck is required. In order to provide a minimum level of performance, data (derived from the AFM AEO out of ground effect (OGE)) should be used to provide the maximum take-off or landing mass. Where a helideck is affected by downdrafts or turbulence or hot gases, or where the take-off or landing profile is obstructed, or the approach or take-off cannot be made into wind, it may be necessary to decrease this take-off or landing mass by using a suitable calculation method. The helicopter mass should not exceed that required by CAT.POL.H.310(a) or CAT.POL.H.325(a).
(For helicopter types no longer supported by the manufacturer, data may be established by the operator, provided it is acceptable to the competent authority.)
(c) Take-off profile
(1) The take-off should be performed in a dynamic manner ensuring that the helicopter continuously moves vertically from the hover to the rotation point (RP) and thence into forward flight. If the manoeuvre is too dynamic, then there is an increased risk of losing spatial awareness (through loss of visual cues) in the event of a rejected take-off, particularly at night.
(2) If the transition to forward flight is too slow, the helicopter is exposed to an increased risk of contacting the deck edge in the event of an engine failure at or just after the point of cyclic input (RP).
(3) It has been found that the climb to RP is best made between 110 % and 120 % of the power required in the hover. This power offers a rate of climb that assists with deck-edge clearance following engine failure at RP, whilst minimising ballooning following a failure before RP. Individual types will require selection of different values within this range.
Figure 1
Take-off profile
(d) Selection of a lateral visual cue
(1) In order to obtain the maximum performance in the event of an engine failure being recognised at or just after RP, the RP should be at its optimum value, consistent with maintaining the necessary visual cues. If an engine failure is recognised just before RP, the helicopter, if operating at a low mass, may ‘balloon’ a significant height before the reject action has any effect. It is, therefore, important that the pilot flying selects a lateral visual marker and maintains it until the RP is achieved, particularly on decks with few visual cues. In the event of a rejected take-off, the lateral marker will be a vital visual cue in assisting the pilot to carry out a successful landing.
(e) Selection of the rotation point
(1) The optimum RP should be selected to ensure that the take-off path will continue upwards and away from the deck with AEO, but minimising the possibility of hitting the deck edge due to the height loss in the event of an engine failure at or just after RP.
(2) The optimum RP may vary from type to type. Lowering the RP will result in a reduced deck edge clearance in the event of an engine failure being recognised at or just after RP. Raising the RP will result in possible loss of visual cues, or a hard landing in the event of an engine failure just prior to RP.
(f) Pilot reaction times
(1) Pilot reaction time is an important factor affecting deck edge clearance in the event of an engine failure prior to or at RP. Simulation has shown that a delay of 1 second can result in a loss of up to 15 ft in deck edge clearance.
(g) Variation of wind speed
(1) Relative wind is an important parameter in the achieved take-off path following an engine failure; wherever practicable, take-off should be made into wind. Simulation has shown that a 10-kt wind can give an extra 5-ft deck edge clearance compared to a zero wind condition.
(h) Position of the helicopter relative to the deck edge
(1) It is important to position the helicopter as close to the deck edge (including safety nets) as possible whilst maintaining sufficient visual cues, particularly a lateral marker.
(2) The ideal position is normally achieved when the rotor tips are positioned at the forward deck edge. This position minimises the risk of striking the deck edge following recognition of an engine failure at or just after RP. Any take-off heading which causes the helicopter to fly over obstructions below and beyond the deck edge should be avoided if possible. Therefore, the final take-off heading and position will be a compromise between the take-off path for least obstructions, relative wind, turbulence and lateral marker cue considerations.
(i) Actions in the event of an engine failure at or just after RP
(1) Once committed to the continued take-off, it is important, in the event of an engine failure, to rotate the aircraft to the optimum attitude in order to give the best chance of missing the deck edge. The optimum pitch rates and absolute pitch attitudes should be detailed in the profile for the specific type.
(j) Take-off from helidecks that have significant movement
(1) This technique should be used when the helideck movement and any other factors, e.g. insufficient visual cues, makes a successful rejected take-off unlikely. Weight should be reduced to permit an improved one-engine-inoperative capability, as necessary.
(2) The optimum take-off moment is when the helideck is level and at its highest point, e.g. horizontal on top of the swell. Collective pitch should be applied positively and sufficiently to make an immediate transition to climbing forward flight. Because of the lack of a hover, the take-off profile should be planned and briefed prior to lift off from the deck.
(k) Standard landing profile
(1) The approach should be commenced into wind to a point outboard of the helideck. Rotor tip clearance from the helideck edge should be maintained until the aircraft approaches this position at the requisite height (type dependent) with approximately 10 kt of ground-speed and a minimal rate of descent. The aircraft is then flown on a flight path to pass over the deck edge and into a hover over the safe landing area.
Figure 2
Standard landing profile
(l) Offset landing profile
(1) If the normal landing profile is impracticable due to obstructions and the prevailing wind velocity, the offset procedure may be used. This should involve flying to a hover position, approximately 90° offset from the landing point, at the appropriate height and maintaining rotor tip clearance from the deck edge. The helicopter should then be flown slowly but positively sideways and down to position in a low hover over the landing point. Normally, the committal point (CP) will be the point at which helicopter begins to transition over the helideck edge.
(m) Training
(1) These techniques should be covered in the training required by Annex III (Part-ORO).
TAKE-OFF AND LANDING TECHNIQUES
(a) This GM describes three types of operation to/from helidecks and elevated FATOs by helicopters operating in performance class 2.
(b) In two cases of take-off and landing, exposure time is used. During the exposure time (which is only approved for use when complying with CAT.POL.H.305), the probability of an engine failure is regarded as extremely remote. If an engine failure occurs during the exposure time, a safe forced landing may not be possible.
(c) Take-off — non-hostile environment (without an approval to operate with an exposure time) CAT.POL.H.310(b).
(1) Figure 1 shows a typical take-off profile for performance class 2 operations from a helideck or an elevated FATO in a non-hostile environment.
(2) If an engine failure occurs during the climb to the rotation point, compliance with CAT.POL.H.310(b) will enable a safe landing or a safe forced landing on the deck.
(3) If an engine failure occurs between the rotation point and the DPATO, compliance with CAT.POL.H.310(b) will enable a safe forced landing on the surface, clearing the deck edge.
(4) At or after the DPATO, the OEI flight path should clear all obstacles by the margins specified in CAT.POL.H.315.
Figure 1
Typical take-off profile PC2 from a helideck/elevated FATO, non-hostile environment
(d) Take-off — non-hostile environment (with exposure time) CAT.POL.H.310(c)
(1) Figure 2 shows a typical take-off profile for performance class 2 operations from a helideck or an elevated FATO in a non-hostile environment (with exposure time).
(2) If an engine failure occurs after the exposure time and before DPATO, compliance with CAT.POL.H.310(c) will enable a safe forced landing on the surface.
(3) At or after the DPATO, the OEI flight path should clear all obstacles by the margins specified in CAT.POL.H.315.
Figure 2
Typical take-off profile PC2 from a helideck/elevated FATO with exposure time, non-hostile environment
(e) Take-off — non-congested hostile environment (with exposure time) CAT.POL.H.310(c)
(1) Figure 3 shows a typical take off profile for performance class 2 operations from a helideck or an elevated FATO in a non-congested hostile environment (with exposure time).
(2) If an engine failure occurs after the exposure time, the helicopter is capable of a safe forced landing or safe continuation of the flight.
(3) At or after the DPATO, the OEI flight path should clear all obstacles by the margins specified in CAT.POL.H.315.
Figure 3
Typical take-off profile PC2 from a helideck/elevated FATO, non-congested hostile environment
(f) Landing — non-hostile environment (without an approval to operate with an exposure time) CAT.POL.H.325(b)
(1) Figure 4 shows a typical landing profile for performance class 2 operations to a helideck or an elevated FATO in a non-hostile environment.
(2) The DPBL is defined as a ‘window’ in terms of airspeed, rate of descent, and height above the landing surface. If an engine failure occurs before the DPBL, the pilot may elect to land or to execute a balked landing.
(3) In the event of an engine failure being recognised after the DPBL and before the committal point, compliance with CAT.POL.H.325(b) will enable a safe forced landing on the surface.
(4) In the event of an engine failure at or after the committal point, compliance with CAT.POL.H.325(b) will enable a safe forced landing on the deck.
Figure 4
Typical landing profile PC2 to a helideck/elevated FATO, non-hostile environment
(g) Landing — non-hostile environment (with exposure time) CAT.POL.H.325(c)
(1) Figure 5 shows a typical landing profile for performance class 2 operations to a helideck or an elevated FATO in a non-hostile environment (with exposure time).
(2) The DPBL is defined as a ‘window’ in terms of airspeed, rate of descent, and height above the landing surface. If an engine failure occurs before the DPBL, the pilot may elect to land or to execute a balked landing.
(3) In the event of an engine failure being recognised before the exposure time, compliance with CAT.POL.H.325(c) will enable a safe forced landing on the surface.
(4) In the event of an engine failure after the exposure time, compliance with CAT.POL.H.325(c) will enable a safe forced landing on the deck.
Figure 5
Typical landing profile PC2 to a helideck/elevated FATO with exposure time, non-hostile environment
(h) Landing — non-congested hostile environment (with exposure time) CAT.POL.H.325(c)
(1) Figure 6 shows a typical landing profile for performance class 2 operations to a helideck or an elevated FATO in a non-congested hostile environment (with exposure time).
(2) In the event of an engine failure at any point during the approach and landing phase up to the start of exposure time, compliance with CAT.POL.H.325(b) will enable the helicopter, after clearing all obstacles under the flight path, to continue the flight.
(3) In the event of an engine failure after the exposure time (i.e. at or after the committal point), a safe forced landing should be possible on the deck.
Figure 6
Typical landing profile PC2 to a helideck/elevated FATO with exposure time, non-congested hostile environment
FACTORS
(a) To ensure that the necessary factors are taken into account, the operator should:
(1) use take-off and landing procedures that are appropriate to the circumstances, and that minimise the risks of collision with obstacles at the individual offshore location under the prevailing conditions; and
(2) use the aircraft flight manual (AFM) performance data or, where such data is not available, alternative data approved by the competent authority, which show take-off and landing masses that take into account drop-down and take-off deck-edge miss, under varying conditions of pressure altitude, temperature, and wind.
(b) Replanning of offshore location take-off or landing masses during the flight should only be performed in accordance with procedures established in the operations manual (OM). These procedures should be simple and safe to carry out, with no significant increase in the crew workload during critical phases of the flight.
CAT.POL.H.315 Take-off flight path
Regulation (EU) No 965/2012
From the defined point after take-off (DPATO) or, as an alternative, no later than 200 ft above the take-off surface, with the critical engine inoperative, the requirements of CAT.POL.H.210(a)(1), (a)(2) and (b) shall be complied with.
CAT.POL.H.320 En-route – critical engine inoperative
Regulation (EU) No 965/2012
The requirement of CAT.POL.H.215 shall be complied with.
Regulation (EU) No 965/2012
(a) The landing mass at the estimated time of landing shall not exceed the maximum mass specified for a rate of climb of 150 ft/min at 300 m (1 000 ft) above the level of the aerodrome or operating site with the critical engine inoperative and the remaining engine(s) operating at an appropriate power rating.
(b) If the critical engine fails at any point in the approach path:
(1) a balked landing can be carried out meeting the requirement of CAT.POL.H.315; or
(2) for operations other than those specified in CAT.POL.H.305, the helicopter can perform a safe forced landing.
(c) For operations in accordance with CAT.POL.H.305, in addition to the requirements of (a):
(1) the landing mass shall not exceed the maximum mass specified in the AFM for an AEO OGE hover in still air with all engines operating at an appropriate power rating; or
(2) for operations to a helideck:
(i) with a helicopter that has an MOPSC of more than 19; or
(ii) any helicopter operated to a helideck located in a hostile environment,
the landing mass shall take into account the procedure and drop down appropriate to the height of the helideck with the critical engine inoperative and the remaining engine(s) operating at an appropriate power rating.
(d) When showing compliance with (a) to (c), account shall be taken of the appropriate parameters of CAT.POL.H.105(c) at the destination aerodrome or any alternate, if required.
(e) That part of the landing after which the requirement of (b)(1) cannot be met shall be conducted in sight of the surface.
TAKE-OFF AND LANDING TECHNIQUES
(a) This GM describes three types of operation to/from helidecks and elevated FATOs by helicopters operating in performance class 2.
(b) In two cases of take-off and landing, exposure time is used. During the exposure time (which is only approved for use when complying with CAT.POL.H.305), the probability of an engine failure is regarded as extremely remote. If an engine failure occurs during the exposure time, a safe forced landing may not be possible.
(c) Take-off — non-hostile environment (without an approval to operate with an exposure time) CAT.POL.H.310(b).
(1) Figure 1 shows a typical take-off profile for performance class 2 operations from a helideck or an elevated FATO in a non-hostile environment.
(2) If an engine failure occurs during the climb to the rotation point, compliance with CAT.POL.H.310(b) will enable a safe landing or a safe forced landing on the deck.
(3) If an engine failure occurs between the rotation point and the DPATO, compliance with CAT.POL.H.310(b) will enable a safe forced landing on the surface, clearing the deck edge.
(4) At or after the DPATO, the OEI flight path should clear all obstacles by the margins specified in CAT.POL.H.315.
Figure 1
Typical take-off profile PC2 from a helideck/elevated FATO, non-hostile environment
(d) Take-off — non-hostile environment (with exposure time) CAT.POL.H.310(c)
(1) Figure 2 shows a typical take-off profile for performance class 2 operations from a helideck or an elevated FATO in a non-hostile environment (with exposure time).
(2) If an engine failure occurs after the exposure time and before DPATO, compliance with CAT.POL.H.310(c) will enable a safe forced landing on the surface.
(3) At or after the DPATO, the OEI flight path should clear all obstacles by the margins specified in CAT.POL.H.315.
Figure 2
Typical take-off profile PC2 from a helideck/elevated FATO with exposure time, non-hostile environment
(e) Take-off — non-congested hostile environment (with exposure time) CAT.POL.H.310(c)
(1) Figure 3 shows a typical take off profile for performance class 2 operations from a helideck or an elevated FATO in a non-congested hostile environment (with exposure time).
(2) If an engine failure occurs after the exposure time, the helicopter is capable of a safe forced landing or safe continuation of the flight.
(3) At or after the DPATO, the OEI flight path should clear all obstacles by the margins specified in CAT.POL.H.315.
Figure 3
Typical take-off profile PC2 from a helideck/elevated FATO, non-congested hostile environment
(f) Landing — non-hostile environment (without an approval to operate with an exposure time) CAT.POL.H.325(b)
(1) Figure 4 shows a typical landing profile for performance class 2 operations to a helideck or an elevated FATO in a non-hostile environment.
(2) The DPBL is defined as a ‘window’ in terms of airspeed, rate of descent, and height above the landing surface. If an engine failure occurs before the DPBL, the pilot may elect to land or to execute a balked landing.
(3) In the event of an engine failure being recognised after the DPBL and before the committal point, compliance with CAT.POL.H.325(b) will enable a safe forced landing on the surface.
(4) In the event of an engine failure at or after the committal point, compliance with CAT.POL.H.325(b) will enable a safe forced landing on the deck.
Figure 4
Typical landing profile PC2 to a helideck/elevated FATO, non-hostile environment
(g) Landing — non-hostile environment (with exposure time) CAT.POL.H.325(c)
(1) Figure 5 shows a typical landing profile for performance class 2 operations to a helideck or an elevated FATO in a non-hostile environment (with exposure time).
(2) The DPBL is defined as a ‘window’ in terms of airspeed, rate of descent, and height above the landing surface. If an engine failure occurs before the DPBL, the pilot may elect to land or to execute a balked landing.
(3) In the event of an engine failure being recognised before the exposure time, compliance with CAT.POL.H.325(c) will enable a safe forced landing on the surface.
(4) In the event of an engine failure after the exposure time, compliance with CAT.POL.H.325(c) will enable a safe forced landing on the deck.
Figure 5
Typical landing profile PC2 to a helideck/elevated FATO with exposure time, non-hostile environment
(h) Landing — non-congested hostile environment (with exposure time) CAT.POL.H.325(c)
(1) Figure 6 shows a typical landing profile for performance class 2 operations to a helideck or an elevated FATO in a non-congested hostile environment (with exposure time).
(2) In the event of an engine failure at any point during the approach and landing phase up to the start of exposure time, compliance with CAT.POL.H.325(b) will enable the helicopter, after clearing all obstacles under the flight path, to continue the flight.
(3) In the event of an engine failure after the exposure time (i.e. at or after the committal point), a safe forced landing should be possible on the deck.
Figure 6
Typical landing profile PC2 to a helideck/elevated FATO with exposure time, non-congested hostile environment
CHAPTER 4 – Performance class 3
Regulation (EU) No 965/2012
(a) Helicopters operated in performance class 3 shall be certified in category A or equivalent as determined by the Agency, or category B.
(b) Operations shall only be conducted in a non-hostile environment, except:
(1)when operating in accordance with CAT.POL.H.420; or
(2) for the take-off and landing phase, when operating in accordance with (c).
(c) Provided the operator is approved in accordance with CAT.POL.H.305, operations may be conducted to/from an aerodrome or operating site located outside a congested hostile environment without an assured safe forced landing capability:
(1) during take-off, before reaching Vy (speed for best rate of climb) or 200 ft above the take-off surface; or
(2) during landing, below 200 ft above the landing surface.
(d) Operations shall not be conducted:
(1) out of sight of the surface;
(2) at night;
(3) when the ceiling is less than 600 ft; or
(4) when the visibility is less than 800 m.
THE TAKE-OFF AND LANDING PHASES (PERFORMANCE CLASS 3)
(a) To understand the use of ground level exposure in performance class 3, it is important first to be aware of the logic behind the use of ‘take-off and landing phases’. Once this is clear, it is easier to appreciate the aspects and limits of the use of ground level exposure. This GM shows the derivation of the term from the ICAO definition of the ‘en-route phase’ and then gives practical examples of the use, and limitations on the use, of ground level exposure in CAT.POL.400(c).
(b) The take-off phase in performance class 1 and performance class 2 may be considered to be bounded by ‘the specified point in the take-off’ from which the take-off flight path begins.
(1) In performance class 1, this specified point is defined as ‘the end of the take-off distance required’.
(2) In performance class 2, this specified point is defined as DPATO or, as an alternative, no later than 200 ft above the take-off surface.
(3) There is no simple equivalent point for bounding of the landing in performance classes 1 & 2.
(c) Take-off flight path is not used in performance class 3 and, consequently, the term ‘take-off and landing phases’ is used to bound the limit of exposure. For the purpose of performance class 3, the take-off and landing phases are as set out in CAT.POL.H.400(c) and are considered to be bounded by:
(1) during take-off before reaching Vy (speed for best rate of climb) or 200 ft above the take-off surface; and
(2) during landing, below 200 ft above the landing surface.
(ICAO Annex 6 Part III, defines en-route phase as being ‘That part of the flight from the end of the take-off and initial climb phase to the commencement of the approach and landing phase.’ The use of take-off and landing phase in this text is used to distinguish the take-off from the initial climb, and the landing from the approach: they are considered to be complementary and not contradictory.)
(d) Ground level exposure — and exposure for elevated FATOs or helidecks in a non-hostile environment — is permitted for operations under an approval in accordance with CAT.POL.H.305. Exposure in this case is limited to the ‘take-off and landing phases’.
The practical effect of bounding of exposure can be illustrated with the following examples:
(1) A clearing: the operator may consider a take-off/landing in a clearing when there is sufficient power, with all engines operating, to clear all obstacles in the take-off path by an adequate margin (this, in ICAO, is meant to indicate 35 ft). Thus, the clearing may be bounded by bushes, fences, wires and, in the extreme, by power lines, high trees, etc. Once the obstacle has been cleared, by using a steep or a vertical climb (which itself may infringe the height velocity (HV) diagram), the helicopter reaches Vy or 200 ft, and from that point a safe forced landing must be possible. The effect is that whilst operation to a clearing is possible, operation to a clearing in the middle of a forest is not (except when operated in accordance with CAT.POL.H.420).
(2) An aerodrome/operating site surrounded by rocks: the same applies when operating to a landing site that is surrounded by rocky ground. Once Vy or 200 ft has been reached, a safe forced landing must be possible.
(3) An elevated FATO or helideck: when operating to an elevated FATO or helideck in performance class 3, exposure is considered to be twofold: firstly, to a deck-edge strike if the engine fails after the decision to transition has been taken; and secondly, to operations in the HV diagram due to the height of the FATO or helideck. Once the take‑off surface has been cleared and the helicopter has reached the knee of the HV diagram, the helicopter should be capable of making a safe forced landing.
(e) Operation in accordance with CAT.POL.400(b) does not permit excursions into a hostile environment as such and is specifically concerned with the absence of space to abort the take‑off or landing when the take-off and landing space are limited; or when operating in the HV diagram.
(f) Specifically, the use of this exception to the requirement for a safe forced landing (during take‑off or landing) does not permit semi-continuous operations over a hostile environment such as a forest or hostile sea area.
Regulation (EU) No 965/2012
(a) The take-off mass shall be the lower of:
(1) the MCTOM; or
(2) the maximum take-off mass specified for a hover in ground effect with all engines operating at take-off power, or if conditions are such that a hover in ground effect is not likely to be established, the take-off mass specified for a hover out of ground effect with all engines operating at take-off power.
(b) Except as provided in CAT.POL.H.400(b), in the event of an engine failure the helicopter shall be able to perform a safe forced landing.
Regulation (EU) No 965/2012
(a) The helicopter shall be able, with all engines operating within the maximum continuous power conditions, to continue along its intended route or to a planned diversion without flying at any point below the appropriate minimum flight altitude.
(b) Except as provided in CAT.POL.H.420, in the event of an engine failure the helicopter shall be able to perform a safe forced landing.
Regulation (EU) No 965/2012
(a) The landing mass of the helicopter at the estimated time of landing shall be the lower of:
(1) the maximum certified landing mass; or
(2) the maximum landing mass specified for a hover in ground effect, with all engines operating at take-off power, or if conditions are such that a hover in ground effect is not likely to be established, the landing mass for a hover out of ground effect with all engines operating at take-off power.
(b) Except as provided in CAT.POL.H.400(b), in the event of an engine failure, the helicopter shall be able to perform a safe forced landing.
CAT.POL.H.420 Helicopter operations over a hostile environment located outside a congested area
Regulation (EU) 2023/1020
(a) Operations over a non-congested hostile environment without a safe forced landing capability with turbine-powered helicopters with an MOPSC of six or less shall only be conducted if the operator has been granted an approval by the competent authority, following a safety risk assessment performed by the operator. Before such operations take place in another Member State, the operator shall obtain an endorsement from the competent authority of that State.
(b) To obtain and maintain such approval the operator shall:
(1) only conduct these operations in the areas and under the conditions specified in the approval;
(2) not conduct these operations under a HEMS approval;
(3) substantiate that helicopter limitations, or other justifiable considerations, preclude the use of the appropriate performance criteria; and
(4)be approved in accordance with CAT.POL.H.305(b).
(c) Notwithstanding CAT.IDE.H.240, such operations may be conducted without supplemental oxygen equipment, provided the cabin altitude does not exceed 10 000 ft for a period in excess of 30 minutes and never exceeds 13 000 ft pressure altitude.
[applicable until 24 May 2024 — Regulation (EU) No 965/2012]
(a) Operations over a non-congested hostile environment without a safe forced landing capability with turbine-powered helicopters with an MOPSC of six or less shall only be conducted if the operator has been granted an approval by the competent authority, following a safety risk assessment performed by the operator. Before such operations take place in another Member State, the operator shall obtain an endorsement from the competent authority of that State.
(b) To obtain and maintain such approval, the operator shall:
(1) only conduct the operations referred to in point (a) in the areas and under the conditions specified in the approval;
(2) INTENTIONALLY LEFT BLANK
(3) substantiate that helicopter limitations, or other justifiable considerations, preclude the use of the appropriate performance criteria;
(4) be approved in accordance with point CAT.POL.H.305(b).
(c) Notwithstanding CAT.IDE.H.240, such operations may be conducted without supplemental oxygen equipment, provided the cabin altitude does not exceed 10 000 ft for a period in excess of 30 minutes and never exceeds 13 000 ft pressure altitude.
[applicable from 25 May 2024 — Implementing Regulation (EU) 2023/1020]
AMC1 CAT.POL.H.420 Helicopter operations over a hostile environment located outside a congested area
SAFETY RISK ASSESSMENT
(a) Introduction
Two cases that are deemed to be acceptable for the alleviation under the conditions of CAT.POL.H.420 for the en-route phase of the flight (operations without an assured safe forced landing capability during take-off and landing phases are subject to a separate approval under CAT.POL.H.400(c)) are flights over mountainous areas and remote areas, both already having been considered by the JAA in comparison to ground transport in the case of remote areas and respectively to multi-engined helicopters in the case of mountain areas.
(1) Remote areas
Remote area operation is acceptable when alternative surface transportation does not provide the same level of safety as helicopter transportation. In this case, the operator should demonstrate why the economic circumstances do not justify replacement of single-engined helicopters by multi-engined helicopters.
(2) Mountainous areas
Current generation twin-engined helicopters may not be able to meet the performance class 1 or 2 requirements at the operational altitude; consequently, the outcome of an engine failure is the same as a single-engined helicopter. In this case, the operator should justify the use of exposure in the en-route phase.
(b) Other areas of operation
For other areas of operations to be considered for the operational approval, a risk assessment should be conducted by the operator that should, at least, consider the following factors:
(1) type of operations and the circumstances of the flight;
(2) area/terrain over which the flight is being conducted;
(3) probability of an engine failure and the consequence of such an event;
(4) safety target;
(5) procedures to maintain the reliability of the engine(s);
(6) installation and utilisation of a usage monitoring system; and
(7) when considered relevant, any available publications on (analysis of) accident or other safety data.
EXAMPLE OF A SAFETY RISK ASSESSMENT
(a) Introduction
Where it can be substantiated that helicopter limitations, or other justifiable considerations, preclude the use of appropriate performance, the approval effectively alleviates from compliance with the requirement in CAT.OP.MPA.137, that requires the availability of surfaces that permit a safe forced landing to be executed.
Circumstances where an engine failure will result in a catastrophic event are those defined for a hostile environment:
(1) a lack of adequate surfaces to perform a safe landing;
(2) the inability to protect the occupants of the helicopter from the elements; or
(3) a lack of search and rescue services to provide rescue consistent with the expected survival time in such environment.
(b) The elements of the risk assessment
The risk assessment process consists of the application of three principles:
— a safety target;
— a helicopter reliability assessment; and
— continuing airworthiness.
(1) The safety target
The main element of the risk assessment when exposure was initially introduced by the JAA into JAR-OPS 3 (NPA OPS-8), was the assumption that turbine engines in helicopters would have failure rates of about 1:100 000 per flying hour — which would permit (against the agreed safety target of 5 x 10-8 per event) an exposure of about 9 seconds for twin-engined helicopters and 18 seconds for single-engined helicopters during the take-off or landing event.
An engine failure in the en-route phase over a hostile environment will inevitably result in a higher risk (in the order of magnitude of 1 x 10-5 per flying hour) to a catastrophic event.
The approval to operate with this high risk of endangering the helicopter occupants should, therefore, only be granted against a comparative risk assessment (i.e. compared to other means of transport, the risk is demonstrated to be lower), or where there is no economic justification to replace single-engined helicopters by multi-engined helicopters.
(2) The reliability assessment
The purpose of the reliability assessment is to ensure that the engine reliability remains at or better than 1 x 10-5.
(3) Continuing airworthiness
Mitigating procedures consist of a number of elements:
(i) the fulfilment of all manufacturers’ safety modifications;
(ii) a comprehensive reporting system (both failures and usage data); and
(iii) the implementation of a usage monitoring system (UMS).
Each of these elements is to ensure that engines, once shown to be sufficiently reliable to meet the safety target, will sustain such reliability (or improve upon it).
The monitoring system is felt to be particularly important as it had already been demonstrated that when such systems are in place, it inculcates a more considered approach to operations. In addition, the elimination of ‘hot starts’, prevented by the UMS, itself minimises the incidents of turbine burst failures.
GM2 CAT.POL.H.420(a) Helicopter operations over a hostile environment located outside a congested area
ENDORSEMENT FROM ANOTHER STATE
(a) Application to another State
To obtain an endorsement from another State, the operator should submit to that State the safety risk assessment and the reasons and justification that preclude the use of appropriate performance criteria, over those hostile areas outside a congested area over which the operator is planning to conduct operations.
(b) Endorsement from another State
Upon receiving the endorsement from another State, the operator should submit it together with the safety risk assessment and the reasons and justification that preclude the use of appropriate performance criteria, to the competent authority issuing the AOC to obtain the approval or extend the existing approval to a new area.
CAT.POL.MAB.100 Mass and balance, loading
Regulation (EU) No 965/2012
(a) During any phase of operation, the loading, mass and centre of gravity (CG) of the aircraft shall comply with the limitations specified in the AFM, or the operations manual if more restrictive.
(b) The operator shall establish the mass and the CG of any aircraft by actual weighing prior to initial entry into service and thereafter at intervals of four years if individual aircraft masses are used, or nine years if fleet masses are used. The accumulated effects of modifications and repairs on the mass and balance shall be accounted for and properly documented. Aircraft shall be reweighed if the effect of modifications on the mass and balance is not accurately known.
(c) The weighing shall be accomplished by the manufacturer of the aircraft or by an approved maintenance organisation.
(d) The operator shall determine the mass of all operating items and crew members included in the aircraft dry operating mass by weighing or by using standard masses. The influence of their position on the aircraft’s CG shall be determined.
(e) The operator shall establish the mass of the traffic load, including any ballast, by actual weighing or by determining the mass of the traffic load in accordance with standard passenger and baggage masses.
(f) In addition to standard masses for passengers and checked baggage, the operator can use standard masses for other load items, if it demonstrates to the competent authority that these items have the same mass or that their masses are within specified tolerances.
(g) The operator shall determine the mass of the fuel load by using the actual density or, if not known, the density calculated in accordance with a method specified in the operations manual.
(h) The operator shall ensure that the loading of:
(1) its aircraft is performed under the supervision of qualified personnel; and
(2) traffic load is consistent with the data used for the calculation of the aircraft mass and balance.
(i) The operator shall comply with additional structural limits such as the floor strength limitations, the maximum load per running metre, the maximum mass per cargo compartment and the maximum seating limit. For helicopters, in addition, the operator shall take account of in-flight changes in loading.
(j) The operator shall specify, in the operations manual, the principles and methods involved in the loading and in the mass and balance system that meet the requirements contained in (a) to (i). This system shall cover all types of intended operations.
CENTRE OF GRAVITY LIMITS — OPERATIONAL CG ENVELOPE AND IN-FLIGHT CG
In the Certificate Limitations section of the AFM, forward and aft CG limits are specified. These limits ensure that the certification stability and control criteria are met throughout the whole flight and allow the proper trim setting for take-off. The operator should ensure that these limits are respected by:
(a) Defining and applying operational margins to the certified CG envelope in order to compensate for the following deviations and errors:
(1) Deviations of actual CG at empty or operating mass from published values due, for example, to weighing errors, unaccounted modifications and/or equipment variations.
(2) Deviations in fuel distribution in tanks from the applicable schedule.
(3) Deviations in the distribution of baggage and cargo in the various compartments as compared with the assumed load distribution as well as inaccuracies in the actual mass of baggage and cargo.
(4) Deviations in actual passenger seating from the seating distribution assumed when preparing the mass and balance documentation. Large CG errors may occur when ‘free seating’, i.e. freedom of passengers to select any seat when entering the aircraft, is permitted. Although in most cases reasonably even longitudinal passenger seating can be expected, there is a risk of an extreme forward or aft seat selection causing very large and unacceptable CG errors, assuming that the balance calculation is done on the basis of an assumed even distribution. The largest errors may occur at a load factor of approximately 50% if all passengers are seated in either the forward or aft half of the cabin. Statistical analysis indicates that the risk of such extreme seating adversely affecting the CG is greatest on small aircraft.
(5) Deviations of the actual CG of cargo and passenger load within individual cargo compartments or cabin sections from the normally assumed mid position.
(6) Deviations of the CG caused by gear and flap positions and by application of the prescribed fuel usage procedure, unless already covered by the certified limits.
(7) Deviations caused by in-flight movement of cabin crew, galley equipment and passengers.
(8) On small aeroplanes, deviations caused by the difference between actual passenger masses and standard passenger masses when such masses are used.
(b) Defining and applying operational procedures in order to:
(1) ensure an even distribution of passengers in the cabin;
(2) take into account any significant CG travel during flight caused by passenger/crew movement; and
(3) take into account any significant CG travel during flight caused by fuel consumption/transfer.
WEIGHING OF AN AIRCRAFT
(a) New aircraft that have been weighed at the factory may be placed into operation without reweighing if the mass and balance records have been adjusted for alterations or modifications to the aircraft. Aircraft transferred from one EU operator to another EU operator do not have to be weighed prior to use by the receiving operator unless more than 4 years have elapsed since the last weighing.
(b) The mass and centre of gravity (CG) position of an aircraft should be revised whenever the cumulative changes to the dry operating mass exceed ±0.5 % of the maximum landing mass or, for aeroplanes, the cumulative change in CG position exceeds 0.5 % of the mean aerodynamic chord. This may be done by weighing the aircraft or by calculation. If the AFM requires to record changes to mass and CG position below these thresholds, or to record changes in any case, and make them known to the commander, mass and CG position should be revised accordingly and made known to the commander.
(c) When weighing an aircraft, normal precautions should be taken consistent with good practices such as:
(1) checking for completeness of the aircraft and equipment;
(2) determining that fluids are properly accounted for;
(3) ensuring that the aircraft is clean; and
(4) ensuring that weighing is accomplished in an enclosed building.
(d) Any equipment used for weighing should be properly calibrated, zeroed, and used in accordance with the manufacturer's instructions. Each scale should be calibrated either by the manufacturer, by a civil department of weights and measures or by an appropriately authorised organisation within two years or within a time period defined by the manufacturer of the weighing equipment, whichever is less. The equipment should enable the mass of the aircraft to be established accurately. One single accuracy criterion for weighing equipment cannot be given. However, the weighing accuracy is considered satisfactory if the accuracy criteria in Table1 are met by the individual scales/cells of the weighing equipment used:
Table 1
Accuracy criteria for weighing equipment
|
For a scale/cell load |
An accuracy of |
|
below 2 000 kg |
±1 % |
|
from 2 000 kg to 20 000 kg |
±20 kg |
|
above 20 000 kg |
±0.1 % |
FLEET MASS AND CG POSITION — AEROPLANES
(a) For a group of aeroplanes of the same model and configuration, an average dry operating mass and CG position may be used as the fleet mass and CG position, provided that:
(1) the dry operating mass of an individual aeroplane does not differ by more than ±0.5 % of the maximum structural landing mass from the established dry operating fleet mass; or
(2) the CG position of an individual aeroplane does not differ by more than ±0.5 % of the mean aerodynamic chord from the established fleet CG.
(b) The operator should verify that, after an equipment or configuration change or after weighing, the aeroplane falls within the tolerances above.
(c) To add an aeroplane to a fleet operated with fleet values, the operator should verify by weighing or calculation that its actual values fall within the tolerances specified in (a)(1) and (2).
(d) To obtain fleet values, the operator should weigh, in the period between two fleet mass evaluations, a certain number of aeroplanes as specified in Table 1, where ‘n’ is the number of aeroplanes in the fleet using fleet values. Those aeroplanes in the fleet that have not been weighed for the longest time should be selected first.
Table 1
Minimum number of weighings to obtain fleet values
|
Number of aeroplanes in the fleet |
Minimum number of weighings |
|
2 or 3 |
n |
|
4 to 9 |
(n + 3)/2 |
|
10 or more |
(n + 51)/10 |
(e) The interval between two fleet mass evaluations should not exceed 48 months.
(f) The fleet values should be updated at least at the end of each fleet mass evaluation.
(g) Aeroplanes that have not been weighed since the last fleet mass evaluation may be kept in a fleet operated with fleet values, provided that the individual values are revised by calculation and stay within the tolerances above. If these individual values no longer fall within the tolerances, the operator should determine new fleet values or operate aeroplanes not falling within the limits with their individual values.
(h) If an individual aeroplane mass is within the dry operating fleet mass tolerance but its CG position exceeds the tolerance, the aeroplane may be operated under the applicable dry operating fleet mass but with an individual CG position.
(i) Aeroplanes for which no mean aerodynamic chord has been published, should be operated with their individual mass and CG position values. They may be operated under the dry operating fleet mass and CG position, provided that a risk assessment has been completed.
DRY OPERATING MASS
The dry operating mass includes:
(a) crew and crew baggage;
(b) catering and removable passenger service equipment; and
(c) tank water and lavatory chemicals.
MASS VALUES FOR CREW MEMBERS
(a) The operator should use the following mass values for crew to determine the dry operating mass:
(1) actual masses including any crew baggage; or
(2) standard masses, including hand baggage, of 85 kg for flight crew/technical crew members and 75 kg for cabin crew members.
(b) The operator should correct the dry operating mass to account for any additional baggage. The position of this additional baggage should be accounted for when establishing the centre of gravity of the aeroplane.
MASS VALUES FOR PASSENGERS AND BAGGAGE
(a) When the number of passenger seats available is:
(1) less than 10 for aeroplanes; or
(2) less than 6 for helicopters,
passenger mass may be calculated on the basis of a statement by, or on behalf of, each passenger, adding to it a predetermined mass to account for hand baggage and clothing.
The predetermined mass for hand baggage and clothing should be established by the operator on the basis of studies relevant to his particular operation. In any case, it should not be less than:
(1) 4 kg for clothing; and
(2) 6 kg for hand baggage.
The passengers’ stated mass and the mass of passengers’ clothing and hand baggage should be checked prior to boarding and adjusted, if necessary. The operator should establish a procedure in the operations manual when to select actual or standard masses and the procedure to be followed when using verbal statements.
(b) When determining the actual mass by weighing, passengers’ personal belongings and hand baggage should be included. Such weighing should be conducted immediately prior to boarding the aircraft.
(c) When determining the mass of passengers by using standard mass values, the standard mass values in Tables 1 and 2 below should be used. The standard masses include hand baggage and the mass of any infant carried by an adult on one passenger seat. Infants occupying separate passenger seats should be considered as children for the purpose of this AMC. When the total number of passenger seats available on an aircraft is 20 or more, the standard masses for males and females in Table 1 should be used. As an alternative, in cases where the total number of passenger seats available is 30 or more, the ‘All Adult’ mass values in Table 1 may be used.
Table 1
Standard masses for passengers — aircraft with a total number of passenger seats of 20 or more
|
Passenger seats: |
20 and more |
30 and more |
|
|
Male |
Female |
All adult |
|
|
All flights except holiday charters |
88 kg |
70 kg |
84 kg |
|
Holiday charters(*) |
83 kg |
69 kg |
76 kg |
|
Children |
35 kg |
35 kg |
35 kg |
(*) Holiday charter means a charter flight that is part of a holiday travel package. On such flights the entire passenger capacity is hired by one or more charterer(s) for the carriage of passengers who are travelling, all or in part by air, on a round- or circle-trip basis for holiday purposes. The holiday charter mass values apply provided that not more than 5 % of passenger seats installed in the aircraft are used for the non-revenue carriage of certain categories of passengers. Categories of passengers such as company personnel, tour operators’ staff, representatives of the press, authority officials, etc. can be included within the 5% without negating the use of holiday charter mass values.
Table 2
Standard masses for passengers — aircraft with a total number of passenger seats of 19 or less
|
Passenger seats: |
1 - 5 |
6 - 9 |
10 - 19 |
|
Male |
104 kg |
96 kg |
92 kg |
|
Female |
86 kg |
78 kg |
74 kg |
|
Children |
35 kg |
35 kg |
35 kg |
(1) On aeroplane flights with 19 passenger seats or less and all helicopter flights where no hand baggage is carried in the cabin or where hand baggage is accounted for separately, 6 kg may be deducted from male and female masses in Table 2. Articles such as an overcoat, an umbrella, a small handbag or purse, reading material or a small camera are not considered as hand baggage.
(2) For helicopter operations in which a survival suit is provided to passengers, 3 kg should be added to the passenger mass value.
(d) Mass values for baggage
(1) Aeroplanes. When the total number of passenger seats available on the aeroplane is 20 or more, the standard mass values for checked baggage of Table 3 should be used.
(2) Helicopters. When the total number of passenger seats available on the helicopters is 20 or more, the standard mass value for checked baggage should be 13 kg.
(3) For aircraft with 19 passenger seats or less, the actual mass of checked baggage should be determined by weighing.
Table 3
Standard masses for baggage — aeroplanes with a total number of passenger seats of 20 or more
|
Type of flight |
Baggage standard mass |
|
Domestic |
11 kg |
|
Within the European region |
13 kg |
|
Intercontinental |
15 kg |
|
All other |
13 kg |
(4) For the purpose of Table 3:
(i) domestic flight means a flight with origin and destination within the borders of one State;
(ii) flights within the European region mean flights, other than domestic flights, whose origin and destination are within the area specified in (d)(5); and
(iii) intercontinental flight means flights beyond the European region with origin and destination in different continents.
(5) Flights within the European region are flights conducted within the following area:
— N7200 E04500
— N4000 E04500
— N3500 E03700
— N3000 E03700
— N3000 W00600
— N2700 W00900
— N2700 W03000
— N6700 W03000
— N7200 W01000
— N7200 E04500
as depicted in Figure 1.
Figure 1
The European region
(e) Other standard masses may be used provided they are calculated on the basis of a detailed weighing survey plan and a reliable statistical analysis method is applied. The operator should advise the competent authority about the intent of the passenger weighing survey and explain the survey plan in general terms. The revised standard mass values should only be used in circumstances comparable with those under which the survey was conducted. Where the revised standard masses exceed those in Tables 1, 2 and 3 of, then such higher values should be used.
(f) On any flight identified as carrying a significant number of passengers whose masses, including hand baggage, are expected to significantly deviate from the standard passenger mass, the operator should determine the actual mass of such passengers by weighing or by adding an adequate mass increment.
(g) If standard mass values for checked baggage are used and a significant number of passengers checked baggage is expected to significantly deviate from the standard baggage mass, the operator should determine the actual mass of such baggage by weighing or by adding an adequate mass increment.
PROCEDURE FOR ESTABLISHING REVISED STANDARD MASS VALUES FOR PASSENGERS AND BAGGAGE
(a) Passengers
(1) Weight sampling method. The average mass of passengers and their hand baggage should be determined by weighing, taking random samples. The selection of random samples should by nature and extent be representative of the passenger volume, considering the type of operation, the frequency of flights on various routes, in/outbound flights, applicable season and seat capacity of the aircraft.
(2) Sample size. The survey plan should cover the weighing of at least the greatest of:
(i) a number of passengers calculated from a pilot sample, using normal statistical procedures and based on a relative confidence range (accuracy) of 1 % for all adult and 2 % for separate male and female average masses; and
(ii) for aircraft:
(A) with a passenger seating capacity of 40 or more, a total of 2 000 passengers; or
(B) with a passenger seating capacity of less than 40, a total number of 50 multiplied by the passenger seating capacity.
(3) Passenger masses. Passenger masses should include the mass of the passengers' belongings that are carried when entering the aircraft. When taking random samples of passenger masses, infants should be weighted together with the accompanying adult.
(4) Weighing location. The location for the weighing of passengers should be selected as close as possible to the aircraft, at a point where a change in the passenger mass by disposing of or by acquiring more personal belongings is unlikely to occur before the passengers board the aircraft.
(5) Weighing machine. The weighing machine used for passenger weighing should have a capacity of at least 150 kg. The mass should be displayed at minimum graduations of 500 g. The weighing machine should have an accuracy of at least 0.5 % or 200 g, whichever is greater.
(6) Recording of mass values. For each flight included in the survey the mass of the passengers, the corresponding passenger category (i.e. male/female/children) and the flight number should be recorded.
(b) Checked baggage. The statistical procedure for determining revised standard baggage mass values based on average baggage masses of the minimum required sample size should comply with (a)(1) and (a)(2). For baggage, the relative confidence range (accuracy) should amount to 1 %. A minimum of 2 000 pieces of checked baggage should be weighed.
(c) Determination of revised standard mass values for passengers and checked baggage
(1) To ensure that, in preference to the use of actual masses determined by weighing, the use of revised standard mass values for passengers and checked baggage does not adversely affect operational safety, a statistical analysis should be carried out. Such an analysis should generate average mass values for passengers and baggage as well as other data.
(2) On aircraft with 20 or more passenger seats, these averages apply as revised standard male and female mass values.
(3) On aircraft with 19 passenger seats or less, the increments in Table 1 should be added to the average passenger mass to obtain the revised standard mass values.
Table 1
Increments for revised standard masses values
|
Number of passenger seats |
Required mass increment |
|
1 – 5 incl. |
16 kg |
|
6 – 9 incl. |
8 kg |
|
10 – 19 incl. |
4 kg |
Alternatively, all adult revised standard (average) mass values may be applied on aircraft with 30 or more passenger seats. Revised standard (average) checked baggage mass values are applicable to aircraft with 20 or more passenger seats.
(4) The revised standard masses should be reviewed at intervals not exceeding 5 years.
(5) All adult revised standard mass values should be based on a male/female ratio of 80/20 in respect of all flights except holiday charters that are 50/50. A different ratio on specific routes or flights may be used, provided supporting data shows that the alternative male/female ratio is conservative and covers at least 84 % of the actual male/female ratios on a sample of at least 100 representative flights.
(6) The resulting average mass values should be rounded to the nearest whole number in kg. Checked baggage mass values should be rounded to the nearest 0.5 kg figure, as appropriate.
(7) When operating on similar routes or networks, operators may pool their weighing surveys provided that in addition to the joint weighing survey results, results from individual operators participating in the joint survey are separately indicated in order to validate the joint survey results.
ADJUSTMENT OF STANDARD MASSES
When standard mass values are used, AMC1 CAT.POL.MAB.100(e) subparagraph (g) states that the operator should identify and adjust the passenger and checked baggage masses in cases where significant numbers of passengers or quantities of baggage are suspected of significantly deviating from the standard values. Therefore, the operations manual should contain instructions to ensure that:
(a) check-in, operations and cabin staff and loading personnel report or take appropriate action when a flight is identified as carrying a significant number of passengers whose masses, including hand baggage, are expected to significantly deviate from the standard passenger mass, and/or groups of passengers carrying exceptionally heavy baggage (e.g. military personnel or sports teams); and
(b) on small aircraft, where the risks of overload and/or CG errors are the greatest, pilots pay special attention to the load and its distribution and make proper adjustments.
STATISTICAL EVALUATION OF PASSENGERS AND BAGGAGE DATA
(a) Sample size
(1) For calculating the required sample size, it is necessary to make an estimate of the standard deviation on the basis of standard deviations calculated for similar populations or for preliminary surveys. The precision of a sample estimate is calculated for 95 % reliability or ‘significance’, i.e. there is a 95 % probability that the true value falls within the specified confidence interval around the estimated value. This standard deviation value is also used for calculating the standard passenger mass.
(2) As a consequence, for the parameters of mass distribution, i.e. mean and standard deviation, three cases have to be distinguished:
(i) μ, σ = the true values of the average passenger mass and standard deviation, which are unknown and which are to be estimated by weighing passenger samples.
(ii) μ’, σ’ = the ‘a priori’ estimates of the average passenger mass and the standard deviation, i.e. values resulting from an earlier survey, which are needed to determine the current sample size.
(iii) 
, s = the estimates for the current true values of m and s, calculated from the sample.
The sample size can then be calculated using the following formula:
where:
n = number of passengers to be weighed (sample size)
e’r = allowed relative confidence range (accuracy) for the estimate of µ by (see also equation in (c)). The allowed relative confidence range specifies the accuracy to be achieved when estimating the true mean. For example, if it is proposed to estimate the true mean to within ±1 %, then e’r will be 1 in the above formula.
1.96 = value from the Gaussian distribution for 95 % significance level of the resulting confidence interval.
(b) Calculation of average mass and standard deviation. If the sample of passengers weighed is drawn at random, then the arithmetic mean of the sample () is an unbiased estimate of the true average mass (µ) of the population.
(1) Arithmetic mean of sample where:
xj = mass values of individual passengers (sampling units).
(2) Standard deviation where:
xj – = deviation of the individual value from the sample mean.
(c) Checking the accuracy of the sample mean. The accuracy (confidence range) which can be ascribed to the sample mean as an indicator of the true mean is a function of the standard deviation of the sample which has to be checked after the sample has been evaluated. This is done using the formula:
whereby er should not exceed 1 % for an all adult average mass and 2 % for an average male and/or female mass. The result of this calculation gives the relative accuracy of the estimate of µ at the 95 % significance level. This means that with 95 % probability, the true average mass µ lies within the interval:
(d) Example of determination of the required sample size and average passenger mass
(1) Introduction. Standard passenger mass values for mass and balance purposes require passenger weighing programs to be carried out. The following example shows the various steps required for establishing the sample size and evaluating the sample data. It is provided primarily for those who are not well versed in statistical computations. All mass figures used throughout the example are entirely fictitious.
(2) Determination of required sample size. For calculating the required sample size, estimates of the standard (average) passenger mass and the standard deviation are needed. The ‘a priori’ estimates from an earlier survey may be used for this purpose. If such estimates are not available, a small representative sample of about 100 passengers should be weighed so that the required values can be calculated. The latter has been assumed for the example.
Step 1: Estimated average passenger mass.
|
n |
xj (kg) |
|
1 |
79.9 |
|
2 |
68.1 |
|
3 |
77.9 |
|
4 |
74.5 |
|
5 |
54.1 |
|
6 |
62.2 |
|
7 |
89.3 |
|
8 |
108.7 |
|
. |
. |
|
85 |
63.2 |
|
86 |
75.4 |
|
|
6 071.6 |
= 70.6 kg
Step 2: Estimated standard deviation.
|
n |
xj |
(xj – |
(xj – |
|
1 |
79.9 |
+9.3 |
86.49 |
|
2 |
68.1 |
–2.5 |
6.25 |
|
3 |
77.9 |
+7.3 |
53.29 |
|
4 |
74.5 |
+3.9 |
15.21 |
|
5 |
54.1 |
–16.5 |
272.25 |
|
6 |
62.2 |
–8.4 |
70.56 |
|
7 |
89.3 |
+18.7 |
349.69 |
|
8 |
108.7 |
+38.1 |
1 451.61 |
|
. |
. |
. |
. |
|
85 |
63.2 |
–7.4 |
54.76 |
|
86 |
75.4 |
–4.8 |
23.04 |
|
|
6 071.6 |
|
34 683.40 |
σ' = 20.20 kg
Step 3: Required sample size.
The required number of passengers to be weighed should be such that the confidence range, e'r does not exceed 1 %, as specified in (c).
n ≥ 3145
The result shows that at least 3 145 passengers should be weighed to achieve the required accuracy. If e’r is chosen as 2 % the result would be n ≥786.
Step 4: After having established the required sample size, a plan for weighing the passengers is to be worked out.
(3) Determination of the passenger average mass
Step 1: Having collected the required number of passenger mass values, the average passenger mass can be calculated. For the purpose of this example, it has been assumed that 3 180 passengers were weighed. The sum of the individual masses amounts to 231 186.2 kg.
n = 3 180
Step 2: Calculation of the standard deviation
For calculating the standard deviation, the method shown in paragraph (2) step 2 should be applied.
s = 15.31 kg
Step 3: Calculation of the accuracy of the sample mean
er = 0.73 %
Step 4: Calculation of the confidence range of the sample mean
72.7 ± 0.5 kg
The result of this calculation shows that there is a 95 % probability of the actual mean for all passengers lying within the range 72.2 kg to 73.2 kg.
GUIDANCE ON PASSENGER WEIGHING SURVEYS
(a) Detailed survey plan
(1) The operator should establish and submit to the competent authority a detailed weighing survey plan that is fully representative of the operation, i.e. the network or route under consideration and the survey should involve the weighing of an adequate number of passengers.
(2) A representative survey plan means a weighing plan specified in terms of weighing locations, dates and flight numbers giving a reasonable reflection of the operator’s timetable and/or area of operation.
(3) The minimum number of passengers to be weighed is the highest of the following:
(i) The number that follows from the means of compliance that the sample should be representative of the total operation to which the results will be applied; this will often prove to be the overriding requirement.
(ii) The number that follows from the statistical requirement specifying the accuracy of the resulting mean values, which should be at least 2 % for male and female standard masses and 1 % for all adult standard masses, where applicable. The required sample size can be estimated on the basis of a pilot sample (at least 100 passengers) or from a previous survey. If analysis of the results of the survey indicates that the requirements on the accuracy of the mean values for male or female standard masses or all adult standard masses, as applicable, are not met, an additional number of representative passengers should be weighed in order to satisfy the statistical requirements.
(4) To avoid unrealistically small samples, a minimum sample size of 2 000 passengers (males + females) is also required, except for small aircraft where in view of the burden of the large number of flights to be weighed to cover 2 000 passengers, a lesser number is considered acceptable.
(b) Execution of weighing programme
(1) At the beginning of the weighing programme, it is important to note, and to account for, the data requirements of the weighing survey report (see (e)).
(2) As far as is practicable, the weighing programme should be conducted in accordance with the specified survey plan.
(3) Passengers and all their personal belongings should be weighed as close as possible to the boarding point and the mass, as well as the associated passenger category (male/female/child), should be recorded.
(c) Analysis of results of weighing survey. The data of the weighing survey should be analysed as explained in this GM. To obtain an insight to variations per flight, per route, etc. this analysis should be carried out in several stages, i.e. by flight, by route, by area, inbound/outbound, etc. Significant deviations from the weighing survey plan should be explained as well as their possible effect(s) on the results.
(d) Results of the weighing survey
(1) The results of the weighing survey should be summarised. Conclusions and any proposed deviations from published standard mass values should be justified. The results of a passenger weighing survey are average masses for passengers, including hand baggage, which may lead to proposals to adjust the standard mass values given in AMC1 CAT.POL.MAB.100(e) Tables 1 and 2. These averages, rounded to the nearest whole number may, in principle, be applied as standard mass values for males and females on aircraft with 20 or more passenger seats. Because of variations in actual passenger masses, the total passenger load also varies and statistical analysis indicates that the risk of a significant overload becomes unacceptable for aircraft with less than 20 seats. This is the reason for passenger mass increments on small aircraft.
(2) The average masses of males and females differ by some 15 kg or more. Because of uncertainties in the male/female ratio, the variation of the total passenger load is greater if all adult standard masses are used than when using separate male and female standard masses. Statistical analysis indicates that the use of all adult standard mass values should be limited to aircraft with 30 passenger seats or more.
(3) Standard mass values for all adults must be based on the averages for males and females found in the sample, taking into account a reference male/female ratio of 80/20 for all flights except holiday charters where a ratio of 50/50 applies. The operator may, based on the data from his weighing programme, or by proving a different male/female ratio, apply for approval of a different ratio on specific routes or flights.
(e) Weighing survey report
The weighing survey report, reflecting the content of (d)(1) - (3), should be prepared in a standard format as follows:
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WEIGHING SURVEY REPORT |
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1 Introduction Objective and brief description of the weighing survey. |
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2 Weighing survey plan Discussion of the selected flight number, airports, dates, etc. Determination of the minimum number of passengers to be weighed. Survey plan. |
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3 Analysis and discussion of weighing survey results Significant deviations from survey plan (if any). Variations in means and standard deviations in the network. Discussion of the (summary of) results. |
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4 Summary of results and conclusions Main results and conclusions. Proposed deviations from published standard mass values. |
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Attachment 1 Applicable summer and/or winter timetables or flight programmes. |
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Attachment 2 Weighing results per flight (showing individual passenger masses and sex); means and standard deviations per flight, per route, per area and for the total network. |
FUEL DENSITY
(a) If the actual fuel density is not known, the operator may use standard fuel density values for determining the mass of the fuel load. Such standard values should be based on current fuel density measurements for the airports or areas concerned.
(b) Typical fuel density values are:
(1) Gasoline (piston engine fuel) – 0.71
(2) JET A1 (Jet fuel JP 1) – 0.79
(3) JET B (Jet fuel JP 4) – 0.76
(4) Oil – 0.88
IN-FLIGHT CHANGES IN LOADING — HELICOPTERS
In-flight changes in loading may occur in hoist operations.
CAT.POL.MAB.105 Mass and balance data and documentation
Regulation (EU) 2018/1975
(a) The operator shall establish mass and balance data and produce mass and balance documentation prior to each flight specifying the load and its distribution. The mass and balance documentation shall enable the commander to determine that the load and its distribution is such that the mass and balance limits of the aircraft are not exceeded. The mass and balance documentation shall contain the following information:
(1) Aircraft registration and type;
(2) Flight identification, number and date;
(3) Name of the commander;
(4) Name of the person who prepared the document;
(5) Dry operating mass and the corresponding CG of the aircraft:
(i) for performance class B aeroplanes and for helicopters the CG position may not need to be on the mass and balance documentation if, for example, the load distribution is in accordance with a pre-calculated balance table or if it can be shown that for the planned operations a correct balance can be ensured, whatever the real load is;
(6) Mass of the fuel at take-off and the mass of trip fuel;
(7) Mass of consumables other than fuel, if applicable;
(8) Load components including passengers, baggage, freight and ballast;
(9) Take-off mass, landing mass and zero fuel mass;
(10) Applicable aircraft CG positions; and
(11) The limiting mass and CG values.
The information above shall be available in flight planning documents or mass and balance systems. Some of this information may be contained in other documents readily available for use.
(b) Where mass and balance data and documentation is generated by a computerised mass and balance system, the operator shall:
(1) verify the integrity of the output data to ensure that the data are within AFM limitations; and
(2) specify the instructions and procedures for its use in its operations manual.
(c) The person supervising the loading of the aircraft shall confirm by hand signature or equivalent that the load and its distribution are in accordance with the mass and balance documentation given to the commander. The commander shall indicate his/her acceptance by hand signature or equivalent.
(d) The operator shall specify procedures for last minute changes to the load to ensure that:
(1) any last minute change after the completion of the mass and balance documentation is brought to the attention of the commander and entered in the flight planning documents containing the mass and balance documentation;
(2) the maximum last minute change allowed in passenger numbers or hold load is specified; and
(3) new mass and balance documentation is prepared if this maximum number is exceeded.
CONTENTS
The mass and balance documentation should include advice to the commander whenever a non-standard method has been used for determining the mass of the load.
INTEGRITY
The operator should verify the integrity of mass and balance data and documentation generated by a computerised mass and balance system, at intervals not exceeding 6 months. The operator should establish a system to check that amendments of its input data are incorporated properly in the system and that the system is operating correctly on a continuous basis.
SIGNATURE OR EQUIVALENT
Where a signature by hand is impracticable or it is desirable to arrange the equivalent verification by electronic means, the following conditions should be applied in order to make an electronic signature the equivalent of a conventional hand-written signature:
(a) electronic ‘signing’ by entering a personal identification number (PIN) code with appropriate security, etc.;
(b) entering the PIN code generates a print-out of the individual’s name and professional capacity on the relevant document(s) in such a way that it is evident, to anyone having a need for that information, who has signed the document;
(c) the computer system logs information to indicate when and where each PIN code has been entered;
(d) the use of the PIN code is, from a legal and responsibility point of view, considered to be fully equivalent to signature by hand;
(e) the requirements for record keeping remain unchanged; and.
(f) all personnel concerned are made aware of the conditions associated with electronic signature and this is documented.
MASS AND BALANCE DOCUMENTATION SENT VIA DATA LINK
Whenever the mass and balance documentation is sent to the aircraft via data link, a copy of the final mass and balance documentation, as accepted by the commander, should be available on the ground.