ICAO Annex 14 Volume I, Chapter 5 Chapter 6

Low-intensity obstacle light-Characteristics 6.3.23 Low-intensity obstacle lights on fixed objects.
Types A and B, shall be fixed-red lights

6.3.24 Low-intensity obstacle lights, Types A and B, shall be in accordance with the specifications in Table 6-3.

6.3.25 Low-intensity obstacle lights, Type C, displayed on vehicles associated with emergency or security shall be flashing-blue and those displayed on other vehicles shall be flashing-yellow.

6.3.26 Low-intensity obstacle lights. Type D. displayed on follow-me vehicles shall be flashing-yellow.

6.3.27 Low-intensity obstacle lights, Types C and D, shall be in accordance with the specifications in Table 6-3.

6.3.28 Low-intensity obstacle lights on objects with limited mobility such as aerobridges shall be fixed-red. The intensity of the lights shall be sufficient to ensure conspicuity considering the intensity of the adjacent lights and the general levels of illumination against which they would normally be
viewed.

6.3.29 Low-intensity obstacle lights on objects with limited mobility shall as a minimum be in accordance with the specifications for low-intensity obstacle lights. Type A, in Table 6-3.

Medium-intensity obstacle light-Characteristics

6.3.30 Medium-intensity obstacle lights, Type A, shall be flashing-white lights, Type B shall be flashing-red lights and Type C shall be fixed-red lights.

6.3.31 Medium-intensity obstacle lights. Types A. B and C, shall be in accordance with the specifications in Table 6-3.

6.3.32 Medium-intensity obstacle lights. Types A and B. located on an object shall flash simultaneously.
High-intensity obstacle light- Characteristics

6.3.33 High-intensity obstacle lights, Types A and B. shall be flashing-white lights.

6.3.34 High-intensity obstacle lights, Types A and B.shall be in accordance with the specifications in Table 6-3.

6.3.35 High-intensity obstacle lights, Type A, located on an object shall flash simultaneously.

6.3.36 Recommendation.- High-intensity obstacle lights, Type B, indicating the presence of a tower supporting
overhead wires, cables, etc., should flash sequentially; first the middle light, second the top light and last, the bottom light. The intervals between flashes of the lights should approximate the following ratios:

Flash interval between
Ratio of cycle time

middle and top light
1/13

top and bottom light
2/13

bottom and middle light
10/13.

Effective intensity, as determined in accordance with the Aerodrome Design Manual. Part 4.

Beam spread is defined as the angle between two directions in a plane for which the intensity is equal to 50% of the lower tolerance value of the intensity shown in columns 4.5 and 6. The beam pattern is not necessarily symmetrical about the elevation angle at which the peak intensity occurs.

Elevation (vertical) angles are referenced to the horizontal.

Intensity at any specified horizontal radial as a percentage of the actual peak intensity at the same radial when operated at each of the intensities shown in columns 4, 5 and 6.

Intensity at any specified horizontal radial as a percentage of the lower tolerance value of the intensity shown in columns 4, 5 and 6.

In addition to specified values, lights shall have sufficient intensity to ensure conspicuity at elevation angles between ±0 and 50.

Peak intensity should be located at approximately 2.5 vertical.

Peak intensity should be located at approximately 17 vertical. fpm-flashes per minute; N/A-not applicable

LISUN following instruments fully meet ICAO Annex 14 Volume I, Chapter 5 Chapter 6

LSG-1950 Goniophotometer for Automotive and Signal Lamps

LSG-1950S Goniophotometer for Traffic Signal Lamps