Northrop XP-79

XP-79 "Flying Ram"

Picture - The sole prototype XP-79B.

Role: Interceptor
Manufacturer: Northrop
Designed by: Jack Northrop
First flight: 12 September 1945
Retired: 12 September 1945
Status: Prototype
Primaryuser: United States Army Air Forces
Number built: 1

The Northrop XP-79 "Flying Ram" was an ambitious American design for a flying wing fighter aircraft; it had several notable design features. Among these, the pilot would operate the aircraft from a prone 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

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 three prototypes designation XP-79 was issued by the USAAF.

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 rocket-powered aircraft built by America to fly.

Originally, it was planned to use a 2,000lbf (9kN) 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 plane was damaged in combat) with a â…›in (3mm) skin thickness at the trailing edge and a ¾in (19mm) thickness at the leading edge. However, the rocket motor using canted rockets to drive the turbopumps was unsatisfactory and the aircraft was fitted with two Westinghouse 19-B (J30) turbojets instead. This led to changing the name to XP-79B. After the failure of the rocket motor, the first two prototypes were canceled.

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.

Testing

The XP-79B (after delays because of bursting tires and brake problems on taxiing trials on the Muroc dry lake) was lost on its first flight 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 project was canceled.

Specifications (XP-79B Flying Ram)

Data from

General characteristics

Crew: 1
Length: 14 ft 0 in (4.27 m)
Wingspan: 28 ft 0 in (8.54 m)
Height: 7 ft 0 in (2.13 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: 2x— Westinghouse 19B turbojet, 1,150 lbf (5.1kN) each

Performance

Maximum speed: 547 mph (880 km/h)
Range: 993 mi (1,598 km)
Service ceiling: 40,000 ft (12,200 m)
Rate of climb: 4,000 ft/min (1,220 m/min)
Wing loading: 31 lb/ft² (153 kg/m²)
Thrust/weight: 0.27

Armament

Guns: 4 x— .50-cal (12.7 mm) machine guns (never fitted)

Comparable aircraft

Messerschmitt Me 163
Horten Ho 229
Messerschmitt Me 262
Gloster Meteor
Northrop X-4
de Havilland DH 108

Bibliography

Winchester, Jim. The World's Worst Aircraft: From Pioneering Failures to Multimillion Dollar Disasters. London: Amber Books Ltd., 2005. ISBN 1-904687-34-2.
Pape, Garry and Campbell, John. Northrop Flying Wings. Atglen, PA, Schiffer Publications, 1995, ISBN 0-88740-689-0.

Living Warbirds: The best warbirds DVD series.

Source: WikiPedia