Northrop XP-79

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Northrop XP-79.jpg
The sole prototype XP-79B.
Role Interceptor
Manufacturer Northrop Corporation
Designer Jack Northrop
First flight 12 September 1945
Retired 12 September 1945
Status Crashed, out of service
Primary user United States Army Air Forces
Number built 1

The Northrop XP-79 was an ambitious design for a flying wing fighter aircraft, designed by Northrop. It had several notable design features; among these, the pilot would operate the aircraft from a lying position, permitting the pilot to withstand much greater g-forces in the upward and downward direction with respect to the plane – and welded magnesium monocoque structure instead of riveted aluminum.

Design and development[edit]

In 1942, John K. Northrop conceived the XP-79 as a high-speed rocket-powered flying-wing fighter aircraft.

In January 1943, a contract for two prototypes (s/n's 43-52437 & 43-52438) with designation XP-79 was issued by the United States Army Air Forces.

To test the radical design, glider prototypes were built. One, designated MX-324, was towed into the air on 5 July 1944 by a P-38, making it the first US-built rocket-powered aircraft to fly.[1]

Originally, it was planned to use a 2,000 lbf (9 kN) thrust XCALR-2000A-1 "rotojet" rocket motor supplied by Aerojet that used monoethyl aniline and red fuming nitric acid; because of the corrosive and toxic nature of the liquids, the XP-79 was built using a welded magnesium alloy monocoque structure (to protect the pilot if the aircraft was damaged in combat) with a ⅛ in (3 mm) skin thickness at the trailing edge and a ¾ in (19 mm) thickness at the leading edge. However, the rocket motor configuration using canted rockets to drive the turbopumps was unsatisfactory and the aircraft was subsequently fitted with two Westinghouse 19-B (J30) turbojets instead. This led to changing the designation to XP-79B. After the failure of the rocket motor, further development of the first two prototypes ended.

The pilot controlled the XP-79 through a tiller bar and rudders mounted below; intakes mounted at the wingtips supplied air for the unusual bellows-boosted ailerons.[2]


The XP-79B (after delays because of bursting tires and brake problems on taxiing trials on the Muroc dry lake) was lost during its first flight on 12 September 1945. While performing a slow roll 15 minutes into the flight, control was lost for unknown reasons. The nose dropped and the roll continued with the aircraft impacting in a vertical spin. Test pilot Harry Crosby attempted to bail out but was struck by the aircraft and fell to his death. Shortly thereafter, the second prototype (43-52438) and the overall project was cancelled.

Specifications (XP-79B)[edit]

Data from[citation needed]

General characteristics

  • Crew: one
  • Length: 14 ft 0 in (4.27 m)
  • Wingspan: 38 ft 0 in (11.58 m)
  • Height: 7 ft 6 in (2.29 m)
  • Wing area: 278 ft² (25.8 m²)
  • Empty weight: 5,840 lb (2,650 kg)
  • Loaded weight: 8,669 lb (3,932 kg)
  • Powerplant: 2 × Westinghouse 19B turbojet, 1,150 lbf (5.1kN) each



  • Guns: 4 × .50-cal (12.7 mm) machine guns (never fitted)

See also[edit]

Aircraft of comparable role, configuration and era
Related lists


  1. ^ Winchester 2005, p. 150.
  2. ^ Winchester 2005, p. 151.
  • Jenkins, Dennis R. and Tony R. Landis. Experimental and Prototype U.S. Air Force Jet Fighters. North Branch, Minnesota: Specialty Press, 2008. ISBN 978-1-58007-111-6.
  • Pape, Garry and John Campbell. Northrop Flying Wings. Atglen, Pennsylvania, Schiffer Publications, 1995, ISBN 0-88740-689-0.
  • Winchester, Jim. The World's Worst Aircraft: From Pioneering Failures to Multimillion Dollar Disasters. London: Amber Books Ltd., 2005. ISBN 1-904687-34-2.

External links[edit]