When the airwar against the Japanese Empire began in the early stages of WWII, the only way for the Allies to attack Japanese targets was by flying over the Himalayas from Burma and India. But as the war progressed, the Allies carried out their island hopping campaign to seize Japanese-held islands in the Pacific Ocean, bringing them closer and closer to the Japanese homeland and making it easier for long-range bombers to reach their targets. However, the US still did not have a fighter that was capable of escorting bombers on long over-water missions, some of which could last up to eight hours. Even fighters that proved to be excellent long-range escorts in Europe, such as the Lockheed P-38 Lightning and North American P-51 Mustang, were unable to accompany the bombers on these long flights. And, even if the fighters were able to make the flight, such long missions put an enormous strain on a single pilot. What the US Army Air Forces in the Pacific needed was a fighter with extreme range, but also one with excellent maneuverability, and a second pilot to help with navigation over vast expanses of open ocean.
Beginning in late 1943, North American began working on a fighter with an unrefueled range of 2,000 miles, and they used the remarkable P-51 Mustang as the starting point. North American Design Chief Edgar Schmued began with two P-51H fuselages that had been lengthened behind the cockpit to allow for the installation of additional fuel and other equipment. The fuselages were then connected by a central wing section that housed six .50 caliber machine guns for heavy concentrated fire, while the outer wings were strengthened to carry additional ordnance. The vertical stabilizer was also enlarged to improve single-engine handling. Both cockpits were outfitted with full controls, an arrangement that allowed the two pilots to take turns flying on long missions. A night fighter variant, the F-82F, was fitted with a large radome under the center wing section, and the right cockpit became the radar operator’s station.
The F-82 was originally powered by two Rolls-Royce Merlin V-12 engines, but the Air Force wanted the Twin Mustang to be powered by American engines. So the Merlins were replaced by less powerful Allison V-1710 engines for full production, and the earlier Merlin-powered aircraft were converted to trainers, creating the unique situation where the trainer aircraft were actually faster than the production fighters. The F-82 was finally adopted by the Air Force in the summer of 1945, but when WWII ended soon after, orders were cut drastically and the F-82 entered service too late to see action in the war. With no immediate wartime mission, the true long-range capability of the Twin Mustang was dramatically demonstrated in February 1947 when an F-82B named Betty Jo flew from Hawaii to New York without refueling, covering 5,051 miles and setting a record for piston-engined fighters that still stands.
Though the F-82 was too late to service in WWII, there was still work for it to do. It’s long range made it well-suited to escort early Cold War bombers of the Strategic Air Command, and Twin Mustangs would have been capable of taking off from London for an escort mission to Moscow, with enough fuel for 30 minutes of loiter time over the target and a return flight to England. The F-82 was also one of the first American fighters to see action in the skies over Korea, and was responsible for downing the first three enemy aircraft of the war. The Twin Mustang was retired in 1953 after production of 272 aircraft. Only five F-82s survived scrap yard, and all but one of those are on display in museums or undergoing restoration. After a 10-year restoration, one Twin Mustang, an exceedingly rare preproduction XP-82 prototype, took its first post-restoration flight on January 28, 2019.
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