Northrop F-89 Scorpion - Operational History

Operational History

Production was authorized in January 1949, with the first production F-89A flying in September 1950. It had AN/APG-33 radar and an armament of six 20 mm (.79 in) T-31 cannons with 200 rpg. The swiveling nose turret was abandoned, and 300 US gal (1,100 l) fuel tanks were permanently fitted to the wingtips. Underwing racks could carry 16 5 in (127 mm) aerial rockets or up to 3,200 lb (1,455 kg) of bombs.

Only 18 F-89As were completed, which were mainly used for tests and trials, before the type was upgraded to F-89B standard, with new avionics. The type entered service with the 84th Fighter-Interceptor Squadron in June 1951. These had considerable problems with engines and other systems, and soon gave way to the F-89C. Despite repeated engine changes, problems persisted, compounded by the discovery of structural problems with the wings that led to the grounding of the F-89 and forced a refit of 194 -A, -B, and -C models.

The major production model was the F-89D, which first flew 23 October 1951 and entered service in 1954. It removed the cannon in favor of a new Hughes E-6 fire control system with AN/APG-40 radar and an AN/APA-84 computer. Armament was two pods of 52 2.75 in (70 mm) "Mighty Mouse" FFAR rockets, for a total of 104. A total of 682 were built.

Proposed re-engined F-89s, designated F-89E and F-89F, were not built, nor was a proposed F-89G that would have used Hughes MA-1 fire control and GAR-1/GAR-2 Falcon air-to-air missiles like the Convair F-106 Delta Dart.

The subsequent F-89H, which entered service in 1956, had an E-9 fire control system like that of the early F-102 and massive new wingtip pods each holding three Falcons (usually three semi-active radar homing GAR-1s and three infrared GAR-2s) and 21 FFARs, for a total of six missiles and 42 rockets. Problems with the fire control system delayed the -H's entry into service, by which time its performance was notably inferior to newer supersonic interceptors, so it was phased out of USAF service by 1959.

The final variant was the F-89J. This was based on the F-89D, but replaced the standard wingtip missile pod/tanks with 600 gal (2,271 l) fuel tanks and fitted a pylon under each wing for a single MB-1 Genie nuclear rocket (sometimes supplemented by up to four conventional Falcon air-to-air missiles). The F-89J became the only aircraft to fire a live Genie as the John Shot of Operation Plumbbob on 19 July 1957. There were no new-build F-89Js, but 350 -Ds were modified to this standard. They served with the Air Defense Command, later renamed the Aerospace Defense Command (ADC), through 1959 and with ADC-gained units of the Air National Guard through 1969. This version of the aircraft was extensively used within the Semi Automatic Ground Environment (SAGE) air defense system.

A total of 1,050 Scorpions of all variants were produced.