Document ID: chunk:federal_register_of_legislation:F2024C01244:reg:5:p84
Version: federal_register_of_legislation:F2024C01244
Segment Type: reg
Provision Reference: reg 5 (pt 84/225)
Character Range: 531111–533860

approach lighting array. Consistent spacings, as close as possible to 30 m, will ensure the correct perception of the visual aid by flight crews. Aerodrome operators are recommended to consult with relevant aircraft operators when designing approach lighting arrays.

(b) if crossbars are placed with the application of allowable spacing tolerances shown in Figure 9.41 (2) — such that they are at equidistant intervals between:

 (i) the runway threshold and the first crossbar; and

 (ii) any other crossbars.

       (6) The lighting system must lie as nearly as possible in the horizontal plane passing through the threshold, and be such that:

(a) no object, obstacle or structure, other than an ILS localiser antenna or a far field monitor antenna, protrudes through the plane of the approach lights within a distance of 60 m from the centreline of the system; and

(b) no light, other than a light located within the central part of a crossbar or a centreline barrette (not their extremities), is screened from an approaching aircraft.

Note   All roads and highways are considered as obstacles extending 4.8 m above the crown of the road, except aerodrome service roads where all vehicular traffic is under control of the aerodrome authorities and coordinated with the aerodrome traffic control tower. Railroads, regardless of the amount of traffic, are considered as obstacles extending 5.4 m above the top of the rails.

       (7) An ILS localiser antenna or a far field monitor antenna protruding through the plane of the lights must be treated as an obstacle, and marked and lighted as an obstacle.

       (8) The centreline and crossbar lights of a precision approach CAT I lighting system must:

(a) be fixed lights showing variable white; and

(b) for each centreline light position — consist of:

           (i) 1 light source from the runway threshold to Point B, 2 light sources from Point B to Point D and 3 light sources beyond Point D, to provide distance information; or

           (ii) a barrette.

       (9) A barrette must be:

(a) at least 4 m in length; and

(b) if composed of lights approximating to point sources — composed of such lights uniformly spaced at intervals of not more than 1.5 m.

       (10) If the centreline consists of barrettes, each barrette that is at or beyond Point B (in the direction towards the end of the array of barrettes) must be supplemented by a sequenced flashing light, which must:

(a) be flashed twice a second in sequence, beginning with the outermost light of the system, and progressing toward the threshold to the innermost light; and

(b) be of such electrical circuit design that it can be operated independently of the other lights of the approach lighting system; and

(c)