New portable runway lights developed for military use can shine in either a standard visible wavelength or quickly switch to a covert infra-red mode that can be detected only with night-vision gear. During recent tests of the system in Wisconsin, pilots of a C-130 were able to detect the infra-red LEDs (light-emitting diodes) from 25 miles away. The lights are meant to be used in war zones where the military may need to quickly establish makeshift runways and operate them secretly. The LEDs are brighter, last longer, and are cheaper to operate and maintain than standard incandescent lighting. Engineers at the Air Force Research Laboratory's Human Effectivness Directorate developed the system.
A commercial version of the lights, which operates only in the visual range, has been bought by an airport in Tampa, Fla. The blue, omni-directional lights will be used to light the edges of taxiways.