Glue two P-51 Mustangs together along the wing. Share a tailplane between them. Put the radio operator's seat in the right fuselage. Tell the pilot in the left fuselage to fly the aircraft. The result is the F-82 Twin Mustang — the longest-range piston fighter ever built, the last propeller-driven fighter the United States Air Force ever ordered new, and the aircraft that scored the first American air-to-air kill of the Korean War.

It looks like a hoax. It absolutely was not. North American built 272 of them, and the design was dead serious.

Why Build a Two-Headed Fighter?

The B-29 Superfortress could fly to Tokyo from Saipan. No fighter could. The P-51 Mustang's 1,500-mile range was extraordinary for a single-engine fighter, but it still meant a Pacific bomber escort was a one-way mission. North American Aviation's solution was simple: take two P-51s and weld them into one aircraft. Two pilots could share the workload on a 12-hour mission. Two engines meant survivability.

The aircraft that emerged was not actually two P-51s — every part except some superficial details was redesigned — but the Twin Mustang inherited its parent's elegance and added the brute endurance the Pacific war demanded. Then Japan surrendered. The Twin Mustang arrived too late for what it was designed for.

Korea Saved It

The USAF kept buying anyway. By 1950, when North Korea invaded the South, the F-82 was the only American fighter at Itazuke air base in Japan that could fly all the way to the Korean front, fight, and return. On 27 June 1950 — the third day of the war — three F-82s of the 68th Fighter All-Weather Squadron tangled with a flight of North Korean Yak-9s and La-7s over Seoul. Lieutenant William G. Hudson shot down a Yak-11 trainer being used as a fighter. It was the first American kill of the war.

The Twin Mustangs flew night-fighter missions, ground attack, and convoy escort through the first year of the war. They were finally retired in 1953 as the F-86 Sabre took over. The last operational F-82 was withdrawn from Alaska's air defence mission in 1953 — the very last front-line piston fighter in the US Air Force inventory.

The Twin That Defined a Boundary

The F-82 marked an exact line in aviation history. It was the last new-build piston fighter in American service, and it was beaten into retirement by the same conflict that gave it its only kills. It is also one of the very few aircraft built specifically to use a peculiar layout — twin fuselages — that other engineers tried and abandoned. The German Luftwaffe had Heinkel He 111Z (two He 111s glued together to tow a glider). The British had nothing comparable. Only the Americans actually got the layout to work as a fighter.

Five Twin Mustangs survive today — and one of them flies. After a decade-long restoration, the XP-82 prototype returned to the air on 31 December 2018 and has appeared at airshows since. The others sit in their hangars looking like nothing else in aviation history — twin-headed, oddly graceful, the last of their kind.

Sources: National Museum of the US Air Force, Korean War Project, North American Aviation type history.