The Lockheed F-94 Starfire was a first-generation jet aircraft of the United States Air Force.
It was developed from the twin-seat Lockheed T-33 Shooting Star in the late 1940s as an all-weather, day/night interceptor.
The aircraft reached operational service in May 1950 with Air Defence Command, replacing the piston-engined North American F-82 Twin Mustang in the all-weather interceptor role.
The F-94 was the first operational USAF fighter equipped with an afterburner, and first jet-powered all-weather fighter to enter combat during the Korean War in January 1953.
It had a relatively brief operational life, being replaced in the mid-1950s by the Northrop F-89 Scorpion and North American F-86D Sabre.
The last aircraft left active-duty service in 1958 and Air National Guard service in 1959.
Built to a 1948 USAF specification for a radar-equipped interceptor to replace the aging Northrop F-61 Black Widow and North American F-82 Twin Mustang, it was specifically designed to counter the threat of the USSR’s new Tupolev Tu-4 bombers (reverse-engineered Boeing B-29).
The Curtiss-Wright XF-87 Blackhawk had been designated to be the USAF first jet night fighter, but its performance was subpar, and Lockheed was asked to design a jet night fighter on a crash program basis.
The F-94 was derived from the TF-80C (later T-33A Shooting Star) which was a two-seat trainer version of the F-80 Shooting Star.
A lengthened nose area with guns, radar, and automatic fire control system was added.
Since the conversion seemed so simple, a contract was awarded to Lockheed in early 1949, with the first flight on 16 April 1949.
The early test YF-94s used 75% of the parts used in the earlier F-80 and T-33As.
The fire control system was the Hughes E-1, which incorporated an AN/APG-33 radar (derived from the AN/APG-3, which directed the Convair B-36’s tail guns) and a Sperry A-1C computing gunsight.
This short-range radar system was useful only in the terminal phases of the interception.
Most of the operation would be directed using ground-controlled interception, as was the case with the earlier aircraft it replaced.
The added weight of the electronic equipment required a more powerful engine, so the standard Allison J33A-35 centrifugal turbojet engine, which had been fitted to the T-33A, was replaced with a more powerful afterburning version, the J-33-A-33.
The combination reduced the internal fuel capacity. The F-94 was to be the first US production jet with an afterburner.
The J33-A-33 had standard thrust of 4,000 pounds-force (18 kN), and with water injection this was increased to 5,400 lbf (24 kN) and with afterburning a maximum of 6,000 lbf (27 kN) thrust.
The YF-94A’s afterburner had many teething problems with its igniter and the flame stabilization system.
TF-80Cs converted into YF-94 prototypes, two built.
Initial production version, 109 built.
One F-94A modified on the production line with new flight director, modified hydraulic systems, and two enlarged wingtip tanks.
Production model based on YF-94B, 355 built.
F-94Bs modified with Pratt and Whitney J48 engine, leading edge rocket pods, and swept tailplane, originally designated YF-97A, two modified.
Production version of the YF-94C with longer nose, gun armament replaced with nose mounted rockets, and provision for under fuselage JATO rockets, originally designated F-97A, 387 built.
Test aircraft for proposed reconnaissance variant
Prototype single-seat close support fighter version based on the F-94C, one partly built but construction was abandoned when program was cancelled.
Production version of the YF-94D, 112 on order cancelled, none built.