ED Decision 2003/16/RM
(a) Each engine must have an independent oil system that can supply it with an appropriate quantity of oil at a temperature not above that safe for continuous operation.
(b) The usable oil capacity of each system may not be less than the product of the endurance of the rotorcraft under critical operating conditions and the maximum allowable oil consumption of the engine under the same conditions, plus a suitable margin to ensure adequate circulation and cooling. Instead of a rational analysis of endurance and consumption, a usable oil capacity of 3.8 litres (0.83 Imperial gallon/1 US gallon) for each 151 litres (33.3 Imperial gallons/40 US gallons) of usable fuel may be used for reciprocating engine installations.
(c) Oil-fuel ratios lower than those prescribed in sub-paragraph (b) may be used if they are substantiated by data on the oil consumption of the engine.
(d) The ability of the engine oil cooling provisions to maintain the oil temperature at or below the maximum established value must be shown under the applicable requirements of CS 29.1041 to 29.1049.
ED Decision 2003/16/RM
(a) Installation. Each oil tank installation must meet the requirements of CS 29.967.
(b) Expansion space. Oil tank expansion space must be provided so that –
(1) Each oil tank used with a reciprocating engine has an expansion space of not less than the greater of 10% of the tank capacity or 1.9 litres (0.42 Imperial gallon/0.5 US gallon), and each oil tank used with a turbine engine has an expansion space of not less than 10% of the tank capacity;
(2) Each reserve oil tank not directly connected to any engine has an expansion space of not less than 2% of the tank capacity; and
(3) It is impossible to fill the expansion space inadvertently with the rotorcraft in the normal ground attitude.
(c) Filler connections. Each recessed oil tank filler connection that can retain any appreciable quantity of oil must have a drain that discharges clear of the entire rotorcraft. In addition –
(1) Each oil tank filler cap must provide an oil-tight seal under the pressure expected in operation;
(2) For Category A rotorcraft, each oil tank filler cap or filler cap cover must incorporate features that provide a warning when caps are not fully locked or seated on the filler connection; and
(3) Each oil filler must be marked under CS 29.1557(c)(2).
(d) Vent. Oil tanks must be vented as follows:
(1) Each oil tank must be vented from the top part of the expansion space so that venting is effective under all normal flight conditions.
(2) Oil tank vents must be arranged so that condensed water vapour that might freeze and obstruct the line cannot accumulate at any point.
(e) Outlet. There must be means to prevent entrance into the tank itself, or into the tank outlet, of any object that might obstruct the flow of oil through the system. No oil tank outlet may be enclosed by a screen or guard that would reduce the flow of oil below a safe value at any operating temperature. There must be a shutoff valve at the outlet of each oil tank used with a turbine engine unless the external portion of the oil system (including oil tank supports) is fireproof.
(f) Flexible liners. Each flexible oil tank liner must be approved or shown to be suitable for the particular installation.
ED Decision 2003/16/RM
Each oil tank must be designed and installed so that –
(a) It can withstand, without failure, any vibration, inertia, and fluid loads to which it may be subjected in operation; and
(b) It meets the requirements of CS 29.965, except that instead of the pressure specified in CS 29.965(b) –
(1) For pressurised tanks used with a turbine engine, the test pressure may not be less than 34 kPa (5 psi) plus the maximum operating pressure of the tank; and
(2) For all other tanks, the test pressure may not be less than 34 kPa (5 psi).
CS 29.1017 Oil lines and fittings
ED Decision 2003/16/RM
(a) Each oil line must meet the requirements of CS 29.993.
(b) Breather lines must be arranged so that –
(1) Condensed water vapour that might freeze and obstruct the line cannot accumulate at any point;
(2) The breather discharge will not constitute a fire hazard if foaming occurs, or cause emitted oil to strike the pilot’s windshield; and
(3) The breather does not discharge into the engine air induction system.
CS 29.1019 Oil strainer or filter
ED Decision 2003/16/RM
(a) Each turbine engine installation must incorporate an oil strainer or filter through which all of the engine oil flows and which meets the following requirements:
(1) Each oil strainer or filter that has a bypass must be constructed and installed so that oil will flow at the normal rate through the rest of the system with the strainer or filter completely blocked.
(2) The oil strainer or filter must have the capacity (with respect to operating limitations established for the engine) to ensure that engine oil system functioning is not impaired when the oil is contaminated to a degree (with respect to particle size and density) that is greater than that established for the engine under CS-E.
(3) The oil strainer or filter, unless it is installed at an oil tank outlet, must incorporate a means to indicate contamination before it reaches the capacity established in accordance with subparagraph (a)(2).
(4) The bypass of a strainer or filter must be constructed and installed so that the release of collected contaminants is minimised by appropriate location of the bypass to ensure that collected contaminants are not in the bypass flow path.
(5) An oil strainer or filter that has no bypass, except one that is installed at an oil tank outlet, must have a means to connect it to the warning system required in CS 29.1305(a)(18).
(b) Each oil strainer or filter in a powerplant installation using reciprocating engines must be constructed and installed so that oil will flow at the normal rate through the rest of the system with the strainer or filter element completely blocked.
ED Decision 2003/16/RM
A drain (or drains) must be provided to allow safe drainage of the oil system. Each drain must –
(a) Be accessible; and
(b) Have manual or automatic means for positive locking in the closed position.
ED Decision 2003/16/RM
(a) Each oil radiator must be able to withstand any vibration, inertia, and oil pressure loads to which it would be subjected in operation.
(b) Each oil radiator air duct must be located, or equipped, so that, in case of fire, and with the airflow as it would be with and without the engine operating, flames cannot directly strike the radiator.
ED Decision 2003/16/RM
(a) Each oil shutoff must meet the requirements of CS 29.1189.
(b) The closing of oil shutoffs may not prevent autorotation.
(c) Each oil valve must have positive stops or suitable index provisions in the ‘on’ and ‘off’ positions and must be supported so that no loads resulting from its operation or from accelerated flight conditions are transmitted to the lines attached to the valve.
CS 29.1027 Transmissions and gearboxes: General
ED Decision 2003/16/RM
(a) The oil system for components of the rotor drive system that require continuous lubrication must be sufficiently independent of the lubrication systems of the engine(s) to ensure:
(1) Operation with any engine inoperative; and
(2) Safe autorotation.
(b) Pressure lubrication systems for transmissions and gearboxes must comply with the requirements of CS 29.1013, sub-paragraphs (c), (d) and (f) only, CS 29.1015, 29.1017, 29.1021, 29.1023 and 29.1337(d). In addition, the system must have:
(1) An oil strainer or filter through which all the lubricant flows, and must:
(i) Be designed to remove from the lubricant any contaminant which may damage transmission and drive system components or impede the flow of lubricant to a hazardous degree; and
(ii) Be equipped with a bypass constructed and installed so that:
(A) The lubricant will flow at the normal rate through the rest of the system with the strainer or filter completely blocked; and
(B) The release of collected contaminants is minimised by appropriate location of the bypass to ensure that collected contaminants are not in the bypass flow path;
(iii) Be equipped with a means to indicate collection of contaminants on the filter or strainer at or before opening of the bypass;
(2) For each lubricant tank or sump outlet supplying lubrication to rotor drive systems and rotor drive system components, a screen to prevent entrance into the lubrication system of any object that might obstruct the flow of lubricant from the outlet to the filter required by sub-paragraph (b)(1). The requirements of sub-paragraph (b)(1) do not apply to screens installed at lubricant tank or sump outlets.
(c) Splash type lubrication systems for rotor drive system gearboxes must comply with CS 29.1021 and 29.1337(d).