johnbr

Wing-Northrop-XP-79-Flying-Ram

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 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] [edit] 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 cancelled. [edit] Specifications (XP-79B) Data from[citation needed] 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: 2 × 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 × .50-cal (12.7 mm) machine guns (never fitted)

Wing-Northrop-XP-79-Flying-Ram
johnbr, Nov 30, 2012