14 C.F.R. § 25.1391 — Minimum intensities in the horizontal plane of forward and rear position lights.
§ 25.1391 Minimum intensities in the horizontal plane of forward and rear position lights. Each position light intensity must equal or exceed the applicable values in the following table: Dihedral angle (light included) Angle from right or left of longitudinal axis, measured from dead ahead Intensity (candles) L and R (forward red and green) 0° to 10° 10° to 20° 20° to 110° 40 30 5 A (rear white) 110° to 180° 20