The Douglas F3D Skyknight, later designated as the F-10 Skyknight, is an American twin-engine, mid-wing jet fighter aircraft that was designed and manufactured by the Douglas Aircraft Company.
The aircraft was developed in response to a requirement issued by the United States Navy in 1945 for a jet-powered, radar-equipped, carrier-based night fighter.
Douglas designed the aircraft around the bulky air intercept radar systems of the era, resulting in a wide, deep, and roomy fuselage that accommodated its two-man crew.
An initial contract was issued to Douglas on 3 April 1946, and the XF3D-1 prototype performed its maiden flight on 23 March 1948.
In June 1948, a production contract for 28 F3D-1 production aircraft was received.
The F3D was equipped with a Westinghouse AN/APQ-35 fire control system, which incorporated three separate radars and was an essential component of its night fighter operations.
The Skyknight saw service with the United States Navy and United States Marine Corps, with its primary mission being to locate and destroy enemy aircraft at night.
Although it was not produced in great numbers, the Skyknight achieved numerous firsts in its role as a night fighter during the Korean War, where the type frequently escorted Boeing B-29 Superfortresses on night bombing missions.
It downed several Soviet-built MiG-15s as a night fighter over Korea, although it only sustained a single air-to-air loss against a Chinese MiG-15, which occurred on the night of 29 May 1953.
A total of 237 F3D-2s were completed before production was terminated on 23 March 1952.
The Skyknight played an important role in the development of the radar-guided AIM-7 Sparrow missile, which led to further guided air-to-air missile developments.
It also served as an electronic warfare platform in the Vietnam War as a precursor to the EA-6A Intruder and EA-6B Prowler.
The F3D was not intended to be a typical sleek and nimble dogfighter but as a standoff night fighter, being outfitted with a powerful radar system and a second crew member.
The aircraft originated in 1945 with a US Navy requirement for a jet-powered, radar-equipped, carrier-based night fighter.
The Douglas team led by Ed Heinemann designed the aircraft around the bulky air intercept radar systems of the time, placing the pilot and radar operator in side-by-side seating.
The result was an aircraft with a wide, deep, and roomy fuselage.
Aviation author Joe Copalman observed that the F3D was a relatively conventional aircraft, despite its use of jet propulsion, the design team has opted for features such as a straight wing and traditional tail unit.
A large and relatively flat forward windshield was used, while not conducive to high-speed flight, it provided distortion-free external visibility, something that was particularly valued for a night fighter at that time.
The design team opted not to use tip tanks due to the fuselage already permitting sufficient fuel capacity and the difficulty involved in properly combining the tanks with a folding wing mechanism.
The use of ejection seats was also considered but decided against as their inclusion would have necessitated a jettisonable canopy, made pressurizing the cockpit more difficult, and added weight.
Instead, an escape tunnel was used, similar to the arrangement used in the Douglas A-3 Skywarrior.
The stick was extendable so that more force could be exerted upon it by the pilot as a fallback measure in the event of a hydraulic failure.
The XF3D-1 was selected over a competing submission, Grumman Aircraft Engineering Corporation’s G-75 twin-seat, four-engine, Westinghouse J30-powered night fighter design (similar layout to their Tigercat), leading to an initial contract being issued on 3 April 1946.
The US Navy’s Bureau of Aeronautics (BuAer) also issued a contract to Grumman for two G-75s (BuAer designation XF9F-1) experimental aircraft on 11 April 1946 in case the Skyknight encountered problems.
Shortly thereafter, Grumman recognised that the G-75 would not be a successful aircraft, instead, the company had been working on a completely different single-engine day fighter, initially known as the G-79; it would later become the Grumman F9F Panther. Variants XF3D-1 Prototype aircraft, two Westinghouse J34-WE-24 turbojet engines of 3,000 lbf (13 kN), APQ-35 search and target acquisition radar, four 20mm cannon, three built. F3D-1 Two-seat all-weather day or night-fighter aircraft, powered by two 3,000 lbf (13 kN) Westinghouse J34-WE-32 turbojet engines, tail warning radar, ECM, and other electronics that added over 5,000 lb (2,300 kg) of weight, 28 built. First flight, 13 February 1950. F3D-1M 12 F3D-1s were converted into missile-armed test aircraft, used in the development of the AIM-7 Sparrow air-to-air missile. F3D-2 The second Production version, initially powered by two 3,400 lbf (15 kN) Westinghouse J34-WE-36 and later by two 3,600 lbf (16 kN) Westinghouse J34-WE-38 turbojet engines, 490 kn (560 mph; 910 km/h) at 20,000 ft (6,100 m), equipped with wing spoilers, autopilot and an improved Westinghouse AN/APQ-36 radar, 237 built. First flight, 14 February 1951. F3D-2B One F3D-1 was used for a special armament test in 1952. F3D-2M 16 F3D-2s were converted into missile-armed aircraft. The F3D-2Ms were armed with AIM-7 Sparrow air-to-air missiles. F3D-2Q 35 F3D-2s were converted into electronic warfare aircraft. F3D-2T Five F3D-2s were converted into night fighter training aircraft. F3D-2T2 55 F3D-2s were used as radar-operator trainers and electronic warfare aircraft. F3D-3 Unbuilt project, intended to be an advanced version incorporating swept wings. F-10A 1962 re-designation of the F3D-1. F-10B 1962 re-designation of the F3D-2. EF-10B 1962 re-designation of the F3D-2Q. MF-10A 1962 re-designation of the F3D-1M. MF-10B 1962 re-designation of the F3D-2M. TF-10B 1962 re-designation of the F3D-2T2. Specifications F3D-2 Crew 2 Length 45 ft 5 in (13.84 m) Wingspan 50 ft 0 in (15.24 m) 26 ft 10 in (8.18 m) folded. Height 16 ft 1 in (4.90 m) wings spread, 16 ft 6 in (5.03 m) wings folded. Wing area 400 sq ft (37 m2) Aspect ratio 6.23 Mean Aerodynamic Chord (MAC) 99.8 in (2,530 mm) Airfoil NACA 1412 Empty weight 14,989 lb (6,799 kg) Gross weight 23,575 lb (10,693 kg) Max take-off weight 26,731 lb (12,125 kg) Maximum landing weight 24,500 lb (11,100 kg) Fuel capacity 1,350 US gal (1,120 imp gal; 5,100 L) maximum internal fuel & 2x 150 US gal (120 imp gal; 570 L) optional drop-tanks Powerplant 2 × Westinghouse J34-WE-36 turbojet engines, 3,400 lbf (15 kN) thrust each Performance Maximum speed 460 kn (530 mph, 850 km/h) at 10,000 ft (3,000 m) Cruise speed 395 kn (455 mph, 732 km/h) Stall speed 80.6 kn (92.8 mph, 149.3 km/h) with approach power Combat range 995 nmi (1,145 mi, 1,843 km) on internals Ferry range 1,195 nmi (1,375 mi, 2,213 km) with 2 × 150 USgal drop-tanks. Service ceiling 36,700 ft (11,200 m) G limits +5.5 at 19,700 lb (8,900 kg) +5.1 at 21,374 lb (9,695 kg) +4 at 26,731 lb (12,125 kg) Rate of climb 3,570 ft/min (18.1 m/s) Wing loading 58.9 lb/sq ft (288 kg/m2) Thrust/weight. 0.288 Armament Guns 4 × 20 mm (0.787 in) Hispano-Suiza M2 cannon, 200 rpg Rockets 2 × 11.75 in (298 mm) Tiny Tim unguided rockets Missiles 4× Sparrow I air-to-air missiles (F3D-2M) Bombs 2 × 2,000 lb (910 kg) bombs Avionics AN/APQ-35A or -35B radar Westinghouse AN/APQ-36 radar.
Sources
McDonnell Douglas aircraft since 1920, Volume 1-René J Francillon.
San Diego Air and Space Museum Archive.
The National Museum of the U.S. Air Force.
Douglas F3D Skyknight, MMP Yellow Series No 6135- Jose Fernandez.
Naval Fighters No.4, Douglas F3D Skyknight.
F3D Skyknight in Action, Squadron Signal 10229-Alan C Carey.
F3D/EF-10 Skyknight Units of the Korean and Vietnam Wars- Joe Copalman.
