The Northrop F-89 Scorpion was one of the primary defenders
of North American airspace during the Cold War. A total of 1052
Scorpions were built. During its career, the F-89 equipped 36
active Air Force Units and 17 Air National Guard squadrons. One
of the most heavily armed fighter aircraft, the F-89 was the
backbone of the North American Air Defense Command for more than
17 years. The F-89 was the first multi-seat, all-weather jet
interceptor. It was the first aircraft designed to carry an all-rocket
armament and the first to carry the Hughes Falcon air-to-air
guided missile, and notably the first combat aircraft armed with
air-to-air nuclear weapons (the unguided Genie rocket). The Museums
F-89 is currently located at Cable Airport.
The Scorpion stemmed from a 1945 United States Army Air Forces
Army Air Technical Service Command specification ("Military
Characteristics for All-Weather Fighting Aircraft") for
a jet-powered night fighter to replace the P-61 Black Widow.
Bell Aircraft, Consolidated-Vultee, Douglas Aircraft, Goodyear,
Northrop and Curtiss-Wright all submitted proposals.
Northrop submitted four different designs, prepared by Jack Northrop's
team, including a radical flying wing but settled on the N-24,
a slim-bodied aircraft with a cantilevered mid-mounted wing and
two Allison J35 turbojet engines with afterburners. It was to
have radar and a crew of two, with an armament of four 20 mm
(.79 in) cannon in a unique trainable nose turret. One of the
unusual aspects of the design was the use of Northrop's "Deceleron",
a combination aileron/dive brake/flap that could be accommodated
in the slim wing design. The unique feature added to the prototype
during development was to become a Northrop trademark, still
used today on the B-2 Spirit. Contracts for two prototypes were
issued in December 1946, while Douglas with their XF3D-1 Skynight
and Curtiss for their XF-87 Blackhawk prototypes also were awarded
development contracts.
The initial XP-89 prototype made its first flight on 16 August
1948, with test pilot Fred C. Bretcher at the controls. For much
of the testing period, Curtiss's entry had been the front-runner
for the contract, but in a competition fly-off with its main
competitors, the Northrop design proved superior. Other USAF
interceptors such as the F-94 Starfire and F-86 Sabre had been
adapted from day fighter designs.
Production was authorized in January 1949, with the first production
F-89A being accepted September 28, 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. 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 eighteen 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 F-102 Delta Dagger.
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 F89-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. 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.
XF-89 First prototype, powered by two 4,000 lb. Allison J-35-A-9
engines. XF-89A Second prototype. Fitted with more powerful (5,100
lb. thrust, 6,800 lb. with afterburner) J-35-A-21A engines and
revised, pointed nose with cannon armament. F-89A First production
version, eight built. Fitted with revised tailplane and six cannon
armament. DF-89A F-89As converted into drone control aircraft.
F-89B Second production version with upgraded avionics. 40 built.
DF-89B F-89Bs converted into drone control aircraft. F-89C Third
production version with more powerful engines (5,600 lb. thrust,
7,400 lb. with afterburner J-35-A-21 or -33). 164 built. YF-89D
Conversion of one F-89B to test new avionics and armament of
F-89D. F-89D Main production version which saw deletion of the
six 20 mm (.79 in) cannons in favor of 104 rockets in wing pods,
installation of new Hughes E-6 fire control system, AN/APG-40
radar and the AN/APA-84 computer. This new system allowed the
use of a lead-collision attack in place of the previous lead-pursuit-curve
technique. A total of 682 built. YF-89E One off prototype to
test the Allison YJ71-A-3 engine (7,000 lb. thrust, 9,500 lb.
with afterburner), converted from F-89C. F-89F Proposed version
with new fuselage and wings and J71 engines, never built. F-89G
Proposed version equipped with Hughes MA-1 fire control and GAR-1/GAR-2
Falcon air-to-air missiles, never built. YF-89H Modified F-89D
to test features of F-89H. Three converted. F-89H Version with
E-9 fire control system, six GAR-1/GAR-2 Falcon missiles and
42 Folding Fin Aircraft Rockets (FFAR). 156 built.
Northrop F-89J in 1972 F-89J Conversion of F-89D with underwing
hardpoints for two MB-1 Genie nuclear armed rocket and four Falcon
missiles, and either carrying the standard F-89D rocket/fuel
pod or pure fuel tanks. A total of 350 were converted from F-89Ds.
Operators:
United States United States Air Force
Air National Guard
Data from Scorpion with a Nuclear Sting:
Crew: 2
Length: 53 ft 9½ in (16.40 m)
Wingspan: 59 ft 8½ in (18.20 m)
Height: 17 ft 6 in (5.33 m)
Wing area: 606 ft² (56.30 m²)
Empty weight: 25,194 lb (11,428 kg)
Loaded weight: 37,190 lb (16,869 kg)
Max takeoff weight: 42,241 lb (19,161 kg)
Powerplant: 2 × Allison J35-A-35 afterburning turbojets.
5,440 lb. thrust (24.26 kN) each
Thrust with afterburner: 7,200 lb. (32.11 kN) each
Performance
Maximum speed: 635 mph (552 knots, 1,022 km/h) at 10,600 ft (3,200
m)
Ferry range: 1,366 mi (1,188 nm, 2,200 km)
Service ceiling: 49,200 ft (15,000 m)
Rate of climb: 7,440 ft/min (37.8 m/s)
Armament
Rockets:
104× 2.75 in (70 mm) "Mighty Mouse" folding-fin
aerial rockets
16× 5 in (127 mm) aerial rockets on underwing racks or
