CS 31TGB.71 Function and installation

ED Decision 2013/011/R

(a) Equipment is:

(1) of a kind and design appropriate to its intended function;

(2) labelled as to its identification, function, or operating limitations, or any applicable combination of these factors; and

(3) installed according to limitations specified for that equipment.

(b) Instruments and other equipment do not in themselves, or by their effect upon the balloon, constitute a hazard to safe operation.

(c) The following instruments are installed if required to monitor the operating limitations:

(1) An envelope pressure gauge which displays the limits of permissible internal pressure. The operator is warned by an unambiguous signal if the limit of airborne operating pressure is exceeded.

(2) A temperature measuring device mounted at a point of the envelope that provides a measurement of the operational limitation.

(3) A wind velocity measuring device mounted at the most appropriate point of the envelope.

(4) A load cell at the most appropriate place in order to monitor the tensile force in the tether cable in service.

(5) Device(s) to provide the operational or design limitations information to the operator.

(d) Systems and equipment that need to function properly for safe operation are identified in the operational instructions.

AMC1 31TGB.71(c) Function and installation

ED Decision 2013/011/R

An instrument, in the classical sense, houses the sensor and the indicator (e.g. altimeter). However, it should be noted that for tethered gas balloons the sensor and the indicating display may be mounted far away from each other (e.g. sensor on the top; display in the gondola or at the winch). Hence, the word ‘instrument’ may not necessarily mean an integrated system.

The 'most appropriate place' for the instruments required by subparagraph CS 31TGB.71(c)(2) and (c)(3) shall be established in view of accuracy for measuring the values.

AMC1 31TGB.71(d) Function and installation

ED Decision 2013/011/R

The correct functioning is not to be impaired by icing, heavy rain, high humidity, or low and high temperatures.

When ATC equipment is installed, it is shown that the electrical system is such that the operation of this equipment is not adversely affected.

The operating instructions provide information regarding systems and equipment essential for safe operation. Restrictions or mitigating actions for inoperative systems or equipment are included in the operating instructions to support continued safe operation if applicable.

CS 31TGB.73 Instrument marking

ED Decision 2013/011/R

The following applies to all monitoring instruments:

(a) If the cover glass of the instrument is marked and adequate measures are taken to ensure that the cover glass remains in its correct position relative to the graduated dial.

(b) All markings are sufficiently wide and applied to ensure that they are easily and clearly readable by the operator.

(c) The ranges for analogue indicators are identified as follows:

(1) Normal operating range – green;

(2) Caution area – amber or yellow; and

(3) Permissible maximum or minimum value - red radial line.

(d) For digital indicators, the limits of use are displayed close to the indicator or a red signal is showing when the permissible limits are exceeded.

CS 31TGB.75 Warning, caution, and advisory lights

ED Decision 2013/011/R

If warning, caution or advisory lights are installed, these are:

(a) red, for warning lights (lights that indicate a condition that demands immediate corrective action);

(b) amber or yellow, for caution lights (lights that indicate a condition that requires immediate awareness and the possible need for subsequent corrective action);

(c) green, for safe operation lights; and

(d) of any other colour, including white, for lights not described in paragraphs (a) through (c) of this paragraph, provided the colour differs sufficiently from the colours prescribed in paragraphs (a) through (c) to avoid possible confusion; and

(e) visible under all likely lighting conditions.