The earliest attempt at a powered unmanned aerial vehicle was A. M. Low's "Aerial Target" of 1916.[2] Nikola Tesla described a fleet of unmanned aerial combat vehicles in 1915.[3] A number of remote-controlled airplane advances followed, including the Hewitt-Sperry Automatic Airplane, during and after World War I, including the first scale RPV (Remote Piloted Vehicle), developed by the film star and model airplane enthusiast Reginald Denny in 1935.[2] More were made in the technology rush during World War II; these were used both to train antiaircraft gunners and to fly attack missions. Nazi Germany also produced and used various UAV aircraft during the course of WWII. Jet engines were applied after World War II, in such types as the Teledyne Ryan Firebee I of 1951, while companies like Beechcraft also got in the game with their Model 1001 for the United States Navy in 1955.[2] Nevertheless, they were little more than remote-controlled airplanes until the Vietnam Era.