Aircraft camouflage

Aircraft camouflage is the use of camouflage on military aircraft to make them more difficult to see, whether on the ground or in the air. Given the wide variety of possible backgrounds and lighting conditions, no single scheme works in every situation, and many camouflage schemes have been tried. A common approach has been a form of countershading, the aircraft being painted in a disruptive pattern of ground colours such as green and brown above, sky colours below. For faster and higher-flying aircraft, sky colours have sometimes been used all over, while helicopters and fixed-wing aircraft used close to the ground are often painted entirely in ground camouflage. Aircraft flying by night have often been painted black, but this actually made them appear darker than the night sky, leading to paler night camouflage schemes.

Aircraft were first camouflaged during World War I; aircraft camouflage has been widely employed since then. There is a trade-off between camouflage and aircraft recognition markings, and visible light camouflage has been dispensed with when air superiority was not threatened or when no significant aerial opposition was anticipated.

During and after World War II, the Yehudi lights project developed counter-illumination camouflage using lamps to increase the brightness of the aircraft to match the brightness of the night sky. Recent experiments have again explored active camouflage systems which allow colours, patterns and brightness to be changed to match the background. Stealth technology, as in the Lockheed F-117 Nighthawk, aims to minimise an aircraft's radar cross-section and infrared signature, effectively providing multi-spectral camouflage at the price of reduced flying performance. Stealth may extend to avoiding or preventing vapour contrails.

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Wikipedia