DOUGLAS AIRCRAFT PLANT: United States. 1942. An extensive passive defense effort was initiated in April 1942 to protect the Douglas Aircraft factory in Santa Monica, California, through the application of one of the most extensive camouflage efforts ever undertaken. Volunteers from various Hollywood film studios donated their own time to create a decoy plant several hundred yards away from the actual plant in an open field and to disguise the actual plant as a housing area. Revetments provided protection for aircraft parking, and barrage balloons ringed both the real and decoy plants. However, the main effort used careful painting to transform the runway into an urban residential area and the installation of a three-dimensional framework over the plant buildings complete with plywood houses and trees and bushes constructed of chicken wire and cloth to create a false hill. The camouflage project was essentially completed by October 1942. Although the project was intended to protect the plant from Japanese photoreconnaissance, neither the Japanese Navy nor Army had the capability to undertake such a mission. The level of detail achieved was only possible in a southern California environment; heavy rain or snow would have caused the components to fail, giving away the location.
Sources: Stanley, Roy M. II, To Fool A Glass Eye: Camouflage versus Photoreconnaissance in World War II, Washington, DC, Smithsonian Institution Press, 1998.