The North American F-107A was an experimental supersonic fighter-bomber built in the mid-1950s to compete for a U.S. Air Force production contract. Easily recognized by its unusual dorsal-mounted engine intake positioned above and behind the cockpit, the F-107A was capable of speeds over Mach 2. Only three prototypes were built, and the aircraft seen here, bearing serial 55-5120, is one of them. The Air Force ultimately selected the Republic F-105 Thunderchief for production, and the F-107A program was cancelled, though its prototypes went on to support later flight-research efforts. Project: 218475