Republic F-84 Thunderjet
Republic's first jet fighter, a straight-wing fighter-bomber designed by Alexander Kartveli that first flew in February 1946. After a troubled start that nearly saw it cancelled, the matured F-84G became the U.S. Air Force's primary strike aircraft in Korea and the first fighter able to carry a nuclear weapon. Republic built 4,457 straight-wing Thunderjets between 1947 and 1953, around 60 percent of them earmarked for allied air forces; the swept-wing F-84F Thunderstreak was a different airplane.
Why It Mattered
Vintage Aviation News calls the Thunderjet the Air Force's true workhorse at the dawn of the jet age, and the first postwar American fighter to enter mass production. It was Republic's first jet fighter, designed in 1944 as the intended successor to the piston-engined P-47 Thunderbolt. In Korea it became the Air Force's primary strike aircraft, flying 86,408 missions. Its definitive model, the F-84G, was the first fighter able to carry a nuclear weapon and the first American production aircraft able to refuel in flight. Around 60 percent of all Thunderjets were earmarked for allied air forces, spreading the type across the early Cold War alliance. All of this came after a start so troubled that the Air Force came close to cancelling the program in 1948.
Design Notes
Alexander Kartveli, Republic's chief designer, began work in 1944 on a turbojet-powered replacement for the P-47 Thunderbolt. Attempts to adapt the Thunderbolt's airframe failed, so his team drew a much slimmer fuselage with an axial-flow turbojet at the rear, fed by an intake in the nose. Fuel was carried mainly in the thick, unswept laminar-flow wing — the straight wing that separates the Thunderjet from the swept-wing F-84F that followed. The Army Air Forces had asked for a day fighter able to reach 600 miles per hour. Armament was six .50-calibre machine guns, four in the nose and one in the root of each wing, and later models could carry eight 5-inch rockets under the wings. The wingtip fuel tanks were fitted before their structural effect was understood and contributed to wing failures; the fixes included thicker wing skin and small triangular fins on the tanks. The final F-84G added a framed canopy and a refuelling receptacle in the left wing, and could carry a single Mark 7 nuclear bomb.
Operational History
The first XP-84 flew at Muroc on 28 February 1946, and that September the second prototype set a United States national airspeed record of 607.2 mph. The F-84B became operational with the 14th Fighter Group at Dow Field, Maine, in December 1947. Within months the whole B fleet was grounded by wing structural failures, and a 1948 Air Force review found none of the B or C models capable of executing any aspect of their intended mission. The F-84D, with the structural improvements built in at the factory, entered service in 1949, and the F-84E of 1950 was the first fully capable Thunderjet. Production of the definitive F-84G ran until July 1953 and delivered 3,025 aircraft — 789 to the U.S. Air Force and 2,236 to allies under military aid. Thunderjets reached Korea in December 1950, the 27th Fighter-Escort Wing flying its first missions on 7 December. Outclassed by the MiG-15, the F-84 gave air-to-air combat to the F-86 Sabre and switched to the ground-attack role at which it excelled. Across the war the type flew 86,408 missions, and the USAF claimed its aircraft were responsible for 60 percent of all ground targets destroyed. In air combat, F-84 pilots were credited with eight MiG-15 kills. In 1953 the F-84G became the first aircraft flown by the Thunderbirds, the Air Force's new demonstration team. From August 1953, Strategic Air Command deployed nuclear-capable F-84s to Europe, and by 1955 more than 550 fighters were equipped for the mission.
Afterlife
The F-84G was retired from the U.S. Air Force in mid-1960, while the earlier F-84E lingered with Air National Guard units until 1959. Allied service lasted longer in places: Denmark flew more than 240 F-84Es and F-84Gs between 1951 and 1962. After the Korean cease-fire, production turned exclusively to the swept-wing F-84F Thunderstreak, a different airplane that merely shared the F-84 designation. Survivors are preserved on both sides of the Atlantic: Pima Air & Space Museum displays its F-84C, serial 47-1433, in the markings of the 33rd Fighter Group at Walker AFB in 1948, and the American Airpower Museum displays an F-84. In Denmark, a Thunderjet rebuilt from components of several former Danish aircraft is being restored at Danmarks Flymuseum as the reconnaissance RF-84G KA-C, with formal delivery hoped for in 2028.