The Autogiro Co. of America was formed in 1931 to hold the US licensing rights of the Cierva Autogiro Co, Ltd. of England. Autogiro sublicensed these rights to Kellet Autogiro Co [Philadelphia, PA] and Pitcairn Autogiro Co [Willow Grove, PA], which developed and manufactured a number of autogiros during the 1930s. During World War II, Kellet stopped working on autogiros in favor of helicopters. Pitcairn Autogiro became Pitcairn Larsen Autogiro in 1940 then G&A Aircraft, Inc., which was bought out by Firestone Aircraft in 1943 before fading from the aviation scene. In 1958 Autogiro brought suit against the United Sates, charging that the government had infringed on Autogiro's patent rights by procuring rotary wing aircraft from Bell, Hiller, McCollock, and Vertol/Piasecki, which were not sublicensees of Autogiro's patents.