AFRL Develops Portable Covert Airfield Lighting System

  • Published
  • By Human Effectiveness Directorate
  • AFRL/RH
AFRL engineers worked under a Small Business Innovation Research grant with Optical Research Associates (Pasadena, California) to design and develop a portable covert airfield lighting system (PCALS) based on light-emitting diode (LED) technology rather than conventional incandescent bulbs. The dual-mode runway edge lights can be activated in a visible light mode or switched to an infrared mode, which is visible only through night-vision equipment. The covert mode would guide heavy military cargo aircraft into austere environments, such as Afghanistan and Iraq, where quickly established runways may be short, unpaved, and in hostile territory. The difference between covert and visible mode is the wavelength of light that the LEDs emit.

PCALS operates with a lightweight 4 kW generator, and the LED's lifetime can range up to 100,000 hours. Aerial shipment of a well-packaged production version will require only one C-130 aircraft pallet, as opposed to the three pallets needed for air-transporting other systems. Engineers leveraged LED advances to design a system that is much smaller and lighter, more portable, and less powerhungry than existing portable lighting systems. At the 2005 Team Patriot military mobility exercises, PCALS successfully demonstrated its airfield lighting capacity on a severe, unimproved 5,000 ft airstrip, as well as on the paved, 10,000 ft Volk Field Air National Guard Base (Wisconsin).

Utilizing PCALS during the exercises were a C-130 special operations Air National Guard unit, which used night-vision goggles to fly five approaches to the covert lighting at the unimproved airstrip, and a UH-1 Huey Army National Guard unit, which navigated approaches at both the unimproved and the paved airfields. Pilots from both aircraft reported that they had observed the runway lights about 25 miles from the respective airfields. Additionally, they indicated that they would have seen the lights
from a greater distance in the absence of local cultural lighting.

To help transition the lights to civilian airfields, engineers designed PCALS' visible mode to comply with Federal Aviation Administration requirements governing the medium-intensity visible lighting commonly used for commercial runways. A commercial airfield in Tampa, Florida, purchased the blue, omnidirectional taxiway lights that operate in visible mode only and are observable primarily from the ground. These lights--designed and manufactured by Cooper Crouse-Hinds under subcontract to Optical Research Associates--are less costly for commercial airports to operate and maintain.