Douglas F4D Skyray

The American Douglas F4D Skyray (later redesignated F-6 Skyray) was a carrier-based fighter built by the Douglas Aircraft Company. Although it was in service for a relatively short time and never entered combat, it was notable for being the first carrier-launched aircraft to hold the world absolute speed record and was the first United States Navy fighter capable of exceeding Mach 1 in level flight. 

The Skyray was designed to meet a Navy requirement issued in 1947 for a fighter aircraft capable of intercepting and destroying an enemy aircraft at an altitude of 50,000 ft (15,240 m) within five minutes of the alarm being sounded. The Navy also wanted an aircraft which followed the designs and research of the German aerodynamicist Alexander Lippisch who moved to the U.S. after World War II. 

The Skyray was designed exclusively for the high-altitude interception role and was unsuited to the multi-mission capabilities soon in demand, so it had a short life in Navy and Marine Corps service, the last aircraft being withdrawn from service in 1964.

Douglas F4D Skyray
Class Aircraft
Type Fighter
Manufacturer Douglas Aircraft Company
Origin United States of America
Country Name Origin Year
United States of America 1951
ManufacturerName Production From Production To Quantity
Douglas Aircraft Company 422 View

The Skyray was designed to meet a Navy requirement issued in 1947 for a fighter aircraft that could intercept and destroy an enemy aircraft at an altitude of 50,000 ft (15,240 m) within five minutes of the alarm being sounded. The Navy also wanted an aircraft that followed the designs and research of the German aerodynamicist Alexander Lippisch, who moved to the U.S. after World War II.

The F4D Skyray was a wide delta wing design with long, sharply swept, rounded wings. The design was named for its resemblance to the manta ray. The thick wing roots contained the air intakes feeding a single turbojet engine. Fuel was contained both in the wings and the deep fuselage. Leading edge slats were fitted for increased lift during takeoff and landing, while the trailing edges were mostly elevon control surfaces. Additional pitch trimmers were fitted inboard near the jet exhaust, and were locked upwards on takeoff and landing.

The Westinghouse J40 turbojet was the intended powerplant, but Douglas took a conservative view and designed in contingency options for other power plants. The J40 proved troublesome and was eventually cancelled, and the Skyray was fitted instead with the Pratt & Whitney J57, a more powerful but larger engine.

Production aircraft were not delivered until early 1956, while the United States Marine Corps received their first in 1957. In total, 419 F4D-1 (later designated F-6 in the unified designation system) aircraft were produced.

Its unique design also played a part in making the Skyray one of the best-known early jet fighters. Affectionately known as the "Ford" (after the "Four" and "D" of its designation). In 1953, Edward H. Heinemann was awarded the Collier Trophy in recognition of his design work on the F4D.

In April 1956, VC-3 was the first squadron operational with the F4D-1. This unit was later redesignated VFAW-3 and assigned to NORAD, as the only United States Navy fighter squadron in what was predominantly a United States Air Force and Royal Canadian Air Force organization. VFAW-3 was permanently based at NAS North Island in San Diego.

The U.S. Marine Corps also flew the Skyray. When the Department of Defense adopted a uniform aircraft designation system patterned on the U.S. Air Force aircraft designation system in September 1962, the F4D was redesignated as the F-6A Skyray. In addition to multiple Navy and Marine Corps squadrons, Naval Air Reserve and Marine Air Reserve squadrons VF-881, VF-882 and VMF-215 also flew the Skyray. The last operational squadron was VMF(AW)-115, which flew the Skyray until February 1964.

The Skyray was designed exclusively for the high-altitude interception role with a spectacular rate and angle of climb. The Skyray set a new time to altitude record flying from a standing start to 49,221 feet (15,003 m) in 2 minutes and 36 seconds, all while flying at a 70° pitch angle. As a dedicated interceptor, the F4D was unsuited to the multi-mission capabilities soon in demand, so it had a short career in Navy and Marine Corps service, the last aircraft being withdrawn from service in 1964. Four aircraft were used by NACA (soon to be NASA) until 1969.

Under the new 1962 United States Tri-Service aircraft designation system, the F4D-1 was redesignated the F-6A. The F4D (old designation) should not be confused with the F-4D (new designation) – the latter being the "D" variant of the McDonnell Douglas F-4 Phantom II operated by the U.S. Air Force.

Role Fighter aircraft
Manufacturer Douglas Aircraft Company
Designer Ed Heinemann
First flight 23 January 1951
Introduction 1956
Retired 1964
Status Phased out of service
Primary users United States Navy
United States Marine Corps
Produced 1950–1958
Number built 422
Developed into Douglas F5D Skylancer


General characteristics

  • Crew: 1
  • Length: 33 ft 6 in (10.21 m)
  • Wingspan: 45 ft 3 in (13.8 m)
  • Height: 13 ft 0 in (3.96 m)
  • Wing area: 557 ft (52 m)
  • Empty weight: 16,024 lb (7,268 kg)
  • Loaded weight: 22,648 lb (10,273 kg)
  • Max takeoff weight: 27,116 lb (12,300 kg)
  • Powerplant: 1 x Pratt & Whitney J57-P-8, -8A or -8B turbojet
    • Dry thrust: 10,200 lbf (45 kN)
    • Thrust with afterburner: 16,000 lbf (71 kN)

Performance

  • Maximum speed: 722 mph (627 kts, 1,200 km/h)
  • Range: 700 mi (610 NM, 1,100 km) combat
  • Ferry range: 1,200 mi (1,040 NM, 1,900 km)
  • Service ceiling 55,000 ft (17,000 m)
  • Rate of climb: 18,300 ft/min (93.3 m/s)
  • Wing loading: 41 lb/ft (198 kg/m)
  • Thrust/weight: 0.71

Armament

  • Guns: 4 x 20 mm (0.787 in) Mk 12-0 cannons in wing roots, 65 rounds/gun
  • Rockets:
    • 6 pods of 7 x 2.75 in (70 mm) unguided rockets or
    • 4 pods of 19 x 2.75 (70 mm) unguided rockets
  • Missiles: 2 x AIM-9 Sidewinder air-to-air missiles
  • Bombs: 2 x 2,000 lb (910 kg) bombs

Avionics

  • APQ-50A radar
  • Aero 13F fire-control radar

End notes