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 possible backgrounds and lighting conditions, no single scheme works in every situation. 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. There are trade-offs between camouflage and aircraft recognition markings, and between camouflage and weight. Accordingly, visible light camouflage has been dispensed with when air superiority was not threatened or when no significant aerial opposition was anticipated.
Disruptively camouflaged A-7D Corsairs on a disruptively painted concrete surface, Thailand, 1972
Disruptively patterned French Nieuport 16
Fokker D.VII in lozenge camouflage
Supermarine Spitfire in disruptively patterned RAF 'Sand and Spinach' uppersurface camouflage, 1941
Yehudi lights are lamps of automatically controlled brightness placed on the front and leading edges of an aircraft to raise the aircraft's luminance to the average brightness of the sky, a form of active camouflage using counter-illumination. They were designed to camouflage the aircraft by preventing it from appearing as a dark object against the sky.
Yehudi lights fitted to engine cowling and leading edges of a Grumman TBM-3D Avenger
A maritime patrol Catalina, painted as bright as possible—white—to minimise visibility against the sky, still mainly appears dark. Yehudi lights match brightness better by generating light.
Yehudi lights were tested in B-24 Liberators from 1943.
Yehudi Lights plywood prototype created in the winter of 1943 to demonstrate the concept of counter-illumination using forward-pointing lights on a B-24 Liberator.