Document ID: chunk:federal_register_of_legislation:F2024C01244:reg:5:p83
Version: federal_register_of_legislation:F2024C01244
Segment Type: reg
Provision Reference: reg 5 (pt 83/225)
Character Range: 528640–531382

centreline should be a system length of 900 m (adjustable for the tolerances shown in Figure 9.41 (2). This length enables full design layout of this form of approach lighting system.

Note 2   CASA recommends that for a precision approach CAT I lighting system using a barrette centreline to be considered a full approach lighting system, the design objective should be a system length of at least 720 m.

Note 3   Any precision approach CAT I lighting system that has a length of less than 720 m will likely require compensating increases by the terminal instrument flight procedure designer to the minimum visibility or RVR requirements for any instrument approach conducted to that runway.

Note 4   CASA recommends that aerodrome operators should consult aircraft operators and an instrument flight procedure designer for specific information about the limitations or impact on operating minima of the length and type of approach lighting.

       (3) The lights forming the crossbar must be:

(a) as nearly as possible in a horizontal straight line at right angles to, and bisected by, the line of the centreline lights; and

(b) spaced so as to produce a linear effect, except that gaps may be left on each side of the centreline provided:

           (i) the spacing of the gaps either side of the centreline is kept to a minimum necessary to meet local requirements; and

           (ii) no gap exceeds 6 m.

       (4) Subject to paragraph (3) (b), all spaces between crossbar lights must be:

(a) at least 1 m, but not more than 4 m; and

(b) equal to each other.

Note   Gaps on each side of the centreline may improve directional guidance when approaches are made with a lateral error, and may facilitate the movement of rescue and firefighting vehicles. See ICAO Annex 14, Aerodromes, Volume 1, Aerodrome Design and Operations, Volume I, Attachment A, Section 11 for guidance on installation tolerances. For ICAO documents, see section 1.07.

       (5) As shown in Figure 9.41 (2), the lights forming the centreline must be placed:

(a) at equal longitudinal intervals between the crossbars, or between a crossbar and the threshold, the intervals being, or being as close as possible to, 30 m and not exceeding ± 2 m, with the innermost light located 30 m from the threshold; or

       Note   Due to the location of existing fences, access roads and navigational arrays, it might not be possible to space the centreline lights at 30 m in a section of the 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)