14 CFR § 25.1397 - Color specifications.

§ 25.1397 Color specifications.

Each position light color must have the applicable International Commission on Illumination chromaticity coordinates as follows:

(a) Aviation red

y is not greater than 0.335; and
z is not greater than 0.002.

(b) Aviation green

x is not greater than 0.440−0.320y ;
x is not greater than y−0.170; and
y is not less than 0.390−0.170x.

(c) Aviation white

x is not less than 0.300 and not greater than 0.540;
y is not less than x−0.040; or y0−0.010, whichever is the smaller; and
y is not greater than x + 0.020 nor 0.636−0.400x;
Where y0 is the y coordinate of the Planckian radiator for the value of x considered.
[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25–27, 36 FR 12972, July 10, 1971]