Document ID: chunk:federal_register_of_legislation:F2024C01244:reg:5:p97
Version: federal_register_of_legislation:F2024C01244
Segment Type: reg
Provision Reference: reg 5 (pt 97/225)
Character Range: 563079–565756

the least possible extent with the light signals; and

 (ii) does not affect the elevation of the transition sector; and

 (iii) does not affect the contrast between the red and white signals.

     Figure 9.48 (6)   Light intensity distribution of PAPI (shows matters)

Note   These curves are for minimum intensities in red light. The intensity value in the white sector of the beam is no less than 2, and may be as high as 6.5, times the corresponding intensity value in the red sector.

9.49 Approach slope and elevation setting of light units

        The requirements for the approach slope and elevation setting of PAPI light units for a runway are as follows:

(a) the approach slope, as shown in Figure 9.49, must be appropriate for use by the aeroplanes using the approach;

       Note   The standard approach slope is 3°.

(b) if the runway is a precision approach runway — the siting and elevation of the light units must be such that the PAPI approach slope conforms as closely as possible with the precision approach glide path;

(c) for instrument runways with non-precision approaches — the approach slope must conform as closely as possible with the primary instrument approach procedure;

(d) the angle of elevation settings of the light units in a PAPI wing bar must be such that, during an approach, the pilot of an aeroplane observing a signal of one white light and 3 red lights will clear all objects or structures in the approach area by a safe margin;

       Note   See subsection 9.45 (4) concerning the raising of the approach slope.

(e) if:

 (i) an object or structure located outside the obstacle assessment surface of the PAPI, but within the lateral limits of its light beam, is found to extend above the plane of the obstacle assessment surface; and

  (ii) an aeronautical study indicates that the object or structure could adversely affect the safety of operations;

        then the azimuth spread of the light beam must be restricted so that the object or structure remains outside the confines of the light beam;

(f) if a double-sided PAPI is provided, corresponding units on either side of the runway must be seen at the same angle so that the signals of each wing bar change symmetrically and simultaneously.

     Figure 9.49   Light beams and angle of elevation setting for PAPI 3⁰ approach slope (shows matters)

9.50 Siting a PAPI or a double-sided PAPI

       (1) For a PAPI or a double-sided PAPI:

(a) the light units forming a wing bar must be frangible, and mounted:

 (i) as low as possible; and

 (ii) so as to appear to a pilot of an approaching aeroplane to be substantially in a horizontal line; and

(b) the light