FAA L-865

An FAA L-865 is a white omnidirectional medium intensity aviation obstruction light. The light flashes at a rate of 40 fpm and must flash in sync with any other lights on the structure.

FAA L-865 Intensity Requirements

Step	Beam Spread (Degrees)	Effective Intensity (Candela)
Day	360 horizontal, 3 minimum vertical	20,000 ±25%
Twilight	360 horizontal, 3 minimum vertical	20,000 ±25%
Night	360 horizontal, 3 minimum vertical	2,000 ±25%