Abstract: A dual-color aviation Anti Collision Light (ACL) has a first set of LEDs that emit a substantially white beam of light and a second set of LEDs that emit a substantially red beam of light. The ACL can be operated in a first mode in which the red LEDs are excited by themselves so that the ACL produces a red beam of light In a second mode, the white LEDs and the red LEDs are excited simultaneously to produce a white beam of light having a chromaticity within the definition of Aviation White. Operating the red LEDs in the white mode has two synergistic effects. First, the red LEDs augment the luminous output of the white LEDs so that fewer white LEDs are required, thus saving cost and space. Second, the red LEDs shift the chromaticity of total light output toward the red region. This has the effect of compensating for the tendency of the white LEDs to become greener with age.