The North American Aviation P-51 Mustang was an American long-range single-seat World War II fighter aircraft conceived, designed and built by North American Aviation (NAA) in response to a specification issued directly to NAA by the British Purchasing Commission; the prototype NA-73X airframe was rolled out, although still minus engine, 102 days after the contract was signed. The first production Mustangs were used by the Royal Air Force (RAF) as tactical-reconnaissance aircraft and fighter-bombers. From late 1943, P-51Bs (supplemented by P-51Ds from mid-1944) were used by the USAAF’s Eighth Air Force as bomber escorts in raids over Germany, while the RAF’s 2 TAF and the USAAF’s Ninth Air Force used the Merlin-powered Mustangs as fighter-bombers, roles in which the Mustang helped ensure Allied air superiority in 1944. The P-51 was also in service with Allied air forces in the North African, Mediterranean and Italian theatres, and saw limited service against the Japanese in the Pacific War. At the start of Korean War the Mustang was the United Nations’ main fighter but the role was quickly shouldered by jet fighters, including the F-86, after which the Mustang became a specialised ground-attack fighter-bomber. In spite of being superseded by jet fighters the Mustang remained in service with some air forces until the early 1980s.
The Mustang was first designed to use a low-altitude rated Allison V-1710 engine and was mainly used in the tactical-reconnaissance and fighter-bomber roles. The definitive version, the P-51D, was powered by the Packard V-1650-7, a licence-built version of the Rolls-Royce Merlin 60 series two-stage two-speed supercharged engine, and was able to be used as a long-range bomber escort. The P-51D was armed with six .50 caliber (12.7 mm) M2 Browning machine guns.
After World War II and the Korean War, many Mustangs were converted for civilian use, especially air racing. The Mustang’s reputation was such that, in the early 1960s, the Ford Motor Company designed a new youth-oriented coupe which was named after the fighter.