The North American F-82 Twin Mustang was the last American piston-engine fighter ordered into production by the United States Air Force. Based on the P-51 Mustang, the F-82 was originally designed as a long-range escort fighter in World War II; however, the war ended well before the first production units were operational, so its postwar role changed to that of night-fighting. Radar-equipped F-82s were used extensively by the Air Defense Command as replacements for the Northrop P-61 Black Widow night fighter. During the Korean War, Japan-based F-82s were among the first USAF aircraft to operate over Korea. The first three North Korean aircraft destroyed by U.S. forces were shot down by F-82s, the first being a North-Korean Yak-11 downed over Gimpo Airfield by the USAF 68th Fighter Squadron
The Twin Mustang was developed at the end of the prop-driven fighter era and at the dawn of the jet age. Its designed role as a long-range fighter escort was eliminated by the atomic bombing of Japan and the sudden end of World War II. With the rapid draw-down of the armed forces after the war, the newly established United States Air Force had little money for new prop-driven aircraft, especially since jets, such as the Messerschmitt Me 262 and other Luftwaffe fighters, had been faster than P-51 Mustangs in the skies of Germany in late 1944. The completed airframes (less engines) of the P-82 pre-production aircraft already manufactured by North American went into storage, with an uncertain future.
However, during the 1947 Soviet Aviation Day display at Tushino Airport, a surprise appearance was put in by three four-engined long-range strategic bombers. They were early examples of the Tupolev Tu-4, which was a bolt-for-bolt copy of the Boeing B-29 Superfortress, three examples of which had been interned in the Soviet Union after having been forced to land there during bombing raids against Japan. Since the USSR was expected soon to have nuclear weapons, the appearance of the Soviet Tu-4 was a shock to U.S. military planners, since it meant that the U.S. mainland might soon be vulnerable to nuclear attack from the air.
Until jet interceptors could be developed and put into service, the Twin Mustangs already built were seen as an interim solution to SAC's fighter escort mission for its strategic bomber force and also as an all-weather air defense interceptor
The Twin Mustang had a very short operational life. About two years after its introduction to SAC, the F-82E was phased out of service in favor of the jet-powered F-84 Thunderjet for bomber escort duties beginning in 1950. Some were sent to Korea for combat, others were sent to Alaska, but most were declared surplus and were being sent to storage and ultimately reclamation in 1951. Air Defense Command's F-82Fs began to be replaced by F-94 Starfires in 1950, and by early 1951, with most being sent to the smelters, although a few Twin Mustangs remaining in ADC towing aerial targets. In the Pacific, the F-82Gs in combat were also replaced by the F-94 in late 1951 and early 1952, with the survivors being sent to Alaska after being modified to the F-82H configuration in Japan for cold-weather use.
