AMC1 ADR.OPS.C.015(b);(f) Maintenance of visual aids and electrical systems

LIGHTING SYSTEMS

GROUND CHECKS

(a) As part of the maintenance programme, the lighting system maintenance activities should include ground checks. During the daily checks, the lighting systems should be checked at least for light failures, breakage or gross misalignment and correct operation of the intensity control system.

The maintenance programme should identify the frequency of other checks that need to be performed throughout the year, as well as their content. Moreover, irrespective of the runway type, the aerodrome operator should ensure the serviceability of the lights by conducting photometric measurements, at appropriate intervals, as part of the maintenance programme.

(b) Ground checks of visual approach slope indicator systems (VASIS) should determine their alignment and serviceability. The alignment of VASIS should be checked at defined intervals, taking into account environmental conditions (e.g. rain, drought, etc.) that may affect the stability of the system, using an appropriate intensity setting. Additional checks should be conducted following an aircraft occurrence. Errors in excess of one minute of arc should be corrected. The maintenance programme should also cover the obstacle protection surface of the VASIS to ensure that it is clear of all obstacles.

The serviceability of VASIS should be checked on each runway inspection. With regard to serviceability of the precision approach path indicator (PAPI) and abbreviated precision approach path indicator (APAPI), a unit should be considered to be unserviceable if more than one light is unserviceable and the unit consists of three or more lights; or at least one light is unserviceable and the unit consists of less than three lights. In addition, whenever a red filter does not produce the correct colour light beam, is missing, or is damaged, all the lights associated with that filter should be extinguished until the red filter is rectified.

(c) For a precision approach runway category II or III:

(1) The system of preventive maintenance employed should include at least the following checks:

(i) visual inspection and in-field measurement of the intensity, beam spread and orientation of lights included in the approach and runway lighting systems;

(ii) control and measurement of the electrical characteristics of each circuitry included in the approach and runway lighting systems; and

(iii) control of the correct functioning of light intensity settings used by air traffic control.

(2) In-field measurement of intensity, beam spread and orientation of lights included in approach and runway lighting systems should be undertaken by measuring all lights, as far as practicable, to ensure conformance with the appropriate figure in CS ADR‑DSN.U.940.

(3) Measurement of intensity, beam spread and orientation of lights included in approach and runway lighting systems should be undertaken using an appropriate measuring unit of sufficient accuracy to analyse the characteristics of the individual lights.

(4) The frequency of measurement should be based on traffic density, the local pollution level, the reliability of the installed lighting equipment and the continuous assessment of the results of the in-field measurements but, in any event, should not be less than twice a year for in-pavement lights and not less than once a year for other lights.

FLIGHT CHECKS

(d) As part of the maintenance programme of the lighting systems, flight check of the approach, runway and taxiway lighting systems, VASIS, aerodrome beacon, and the light intensity control system should be carried out at regular intervals, at least on a yearly basis, to ensure that the pattern is correct and that lights are operating properly. Special flight checks should be arranged in case of major maintenance of, or changes to, such systems, as well as before the commissioning of new systems, both at day and night.