I wonder if this thing would have been
prone to
belly landings ...
get it! lol
The Northrop XP-79, USAAF project number MX-365, was an ambitious design for a flying wing fighter aircraft, designed by Northrop.
Top speed: 547 mph
Retired: September 12, 1945
Engine type: Turbojet
First flight: September 12, 1945
Manufacturer: Northrop Corporation
Number built: 1
The Northrop XP-79, USAAF project number MX-365, 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
The MX-334
In 1942, John K. (Jack) 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 (USAAF).
Originally, it was planned to use a 2,000 lbf (8,900 N) thrust XCALR-2000A-1 "rotojet" rocket motor from Aerojet that used mono-ethylaniline fuel and red fuming nitric acid (RFNA) oxidiser. However, the rocket motor configuration using canted rockets to drive the turbo-pumps was unsatisfactory and the aircraft was subsequently fitted with two Westinghouse 19B (J30) turbojets and re-designated XP-79B. After the failure of the rocket motor, further development of the first two prototypes ended.
To protect the pilot if the aircraft was damaged in combat the XP-79 was built using a welded magnesium alloy monocoque structure with a 0.125 in (3.2 mm) skin thickness at the trailing edge and a 0.75 in (19 mm) thickness at the leading edge.
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 split ailerons.
MX-324 and MX-334
To test the radical design, Northrop was given a contract to build three glider demonstrators, to designs from the Engineering Division of the USAAF Materiel Division.[citation needed] Given the Northrop designation NS-12, the three gliders were also given project numbers from the USAAF. Confusingly, two project numbers were used, one MX-324 when discussing secret aspects of the powered gliders, and another, MX-334, relating to the aircraft when being built and flown as pure gliders.
The MX-334 emerged as a flying wing glider with no tail surfaces, similar in layout and construction to the Northrop N-9M. Completed in late Spring 1943 the no.1 MX-334 was tested in NACA Langley's wind tunnel, after which a large wire-braced fin was added to ensure directional stability at high speeds. The first flight attempts was carried out by the no.2 aircraft towed behind a Cadillac car for low level take-off and landing tests, with no success. After modifications the first launch was carried out on 4 September 1943, towed behind a large truck. For more comprehensive testing, a Lockheed P-38 Lightning was used to tow the aircraft on its first proper flight on 2 October 1943.
In early 1944 the no.2 aircraft was modified to take the 2,009 lbf (8,940 N) Aerojet XCAL-200 rocket motor, reverting to the "secret" MX-324 designation. The aircraft was also fitted with combined rudder and airbrakes outboard of the elevons. Testing with the rocket motor commenced on 22 June 1944, with the first aerotow launch for a powered flight on 5 July 1944, making it the first US-built rocket-powered aircraft to fly. Flight testing was concluded by 1 August 1944 and the two remaining aircraft were disposed of. The no.3 MX-334 was written off on its second flight, on 10 November 1943, after Harry Crosby lost control in the prop-wash of the P-38 tug.
Testing
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 canceled.
Variants
Data from: Northrop Flying Wings : a history of Jack Northrop's visionary aircraft
NS-12
Northrop company designation for the MX-324 programme.
NS-14
Northrop designation for the XP-79 programme.
MX-324
The "secret" designation for the powered version of the MX-334 glider. Only used for the no.2 glider, when powered by a single 200 lbf (890 N) Aerojet XCAL-200 liquid-fuelled rocket engine.
MX-334
The designation used to describe the pure glider version ( including the no.2 aircraft before it was fitted with the rocket engine).
MX-365
The USAAC project number for the XP-79 programme
XP-79
The initial design for a rocket powered fighter, to have been powered by 2 x 2,000 lbf (8,900 N) Aerojet XCAL-2000 liquid-fuelled rocket engine.
XP-79B
Three aircraft were ordered but only one was completed, crashing on its first flight on 12 September 1945.
Specifications (XP-79B)
Data from Northrop Flying Wings : a history of Jack Northrop's visionary aircraft[3][4]
General characteristics
Crew: 1
Length: 13.98 ft (4.26 m)
Wingspan: 37.99 ft (11.58 m)
Height: 7.58 ft (2.31 m)
Wing area: 278 sq ft (25.8 m2)
Aspect ratio: 5.19
Airfoil: NACA 66,2-018
Empty weight: 5,842 lb (2,650 kg)
Gross weight: 8,669 lb (3,932 kg)
Fuel capacity: 300 US gal (250 imp gal; 1,100 l)
Powerplant: 2 × Westinghouse 19B axial flow turbojet, 1,150 lbf (5.1 kN) thrust each
Performance
Maximum speed: 547 mph (880 km/h, 475 kn)
Cruise speed: 480 mph (770 km/h, 420 kn)
Range: 993 mi (1,598 km, 863 nmi)
Endurance: 2.45 hours
Service ceiling: 40,000 ft (12,000 m)
Rate of climb: 4,000 ft/min (20 m/s)
Wing loading: 31 lb/sq ft (150 kg/m2)
Thrust/weight: 0.27
Armament
Guns: 4x 0.5 in (12.70 mm) machine-guns
The Northrop XP-79 originated in 1942 as an idea by John K. Northrop for a high-speed flying wing fighter aircraft powered by a rocket engine. Near-sonic speeds were envisaged. The idea was somewhat similar to that which eventually produced the Messerschmitt Me 163 rocket-powered interceptor in Germany.
The Northrop fighter project was to be powered by a 2000 pound thrust Aerojet rocket engine, with takeoff being assisted by a pair of 1000 pound thrust rocket boosters which would be dropped after takeoff. The Aerojet rocket engine was to be powered by hypergolic fuels which combust simply by mixing. Northrop proposed that this airplane be flown by a pilot lying prone in the cockpit, since it was hoped that this would reduce strain on the pilot during violent maneuver and would present a minimum silhouette to enemy gunners.
In January of 1943, the USAAF issued a contract for three prototypes under the designation XP-79. The availability of jet engines led to a decision in March to replace the rocket engine by two Westinghouse 19-B turbojets in the third prototype, which was redesignated XP-79B.
Since the layout of the fighter was so radical, it was thought that test glider prototypes should be built to verify the validity of the concept. One of these was designated MX-324, and was fitted with a fixed tricycle landing gear. The MX-324 was towed into the air by a P-38 on July 5, 1944, and became the first American-built rocket-powered aircraft to fly.
Delays in the development of the Aerojet rocket engine caused the USAAF to cancel the two XP-79s, leaving only the XP-79B. The serial number of the XP-79B was 43-52437. The XP-79B was finally ready for flight testing in the summer of 1945. The pilot lay prone in an unpressurized cockpit situated between the two turbojets. The flying wing was of semimonocoque construction and was built largely of magnesium in order to save weight. Instead of conventional ailerons, the wing had air intakes at the tips for lateral control, in much the same manner as the XP-56. The aircraft was equipped with a pair of vertical tails, presaging the MiG-25 and the F-15. The retractable landing gear consisted of four wheels, two each in tandem.
Supposedly, the XP-79B was to use a rather unusual technique for destroying enemy aircraft. The wing leading edge was reinforced so that it could slice off the wings or tails of enemy aircraft by ramming them! It turns out that this was never true, the ramming claim being a PR gimmick that got out of hand. But it eventually became part of the historical lore, being accepted as truth by numerous aviation historians. Actually, the XP-79B planned to destroy enemy aircraft strictly by conventional means, being equipped with an armament of four 0.50-inch machine guns in the wing leading edge. It was true that there was indeed an armored wing leading edge, but this was intended to protect the aircraft from head-on gunfire.
The XP-79B was transferred to Muroc Dry Lake in June of 1945. Flight testing was delayed by problems with bursting tires during ground taxiing trials. On September 12, 1945, test pilot Harry Crosby finally took the XP-79B up in the air for the first time. It flew all right for about fifteen minutes, but the plane then suddenly went into a spin from which it proved impossible to recover. Crosby attempted to parachute to safety, but his chute failed to open and he was killed. The XP-79B impacted in the desert and was destroyed in the resulting fire. Magnesium burns very nicely.
.
Although the mishap that cost Harry Crosby his life could have been corrected, the USAAF decided to abandon the project.
Specification of the XP-79B:
Powered by a pair of 1365 lb. st. Westinghouse 19B turbojets. Wingspan was 28 feet, length 14 feet, and height was 7 feet. Wing area was 278 square feet. Gross weight was 8669 pounds. Estimated performance included a maximum speed of 547 mph at 20,000 feet, an initial climb rate of 4000 feet, a service ceiling of 40,000 feet, and a range of 993 miles. The proposed armament of four 0.50-in machine guns was never fitted.
Sources:
American Combat Planes, Ray Wagner, Third Enlarged Edition, Doubleday, 1982.
The American Fighter, Enzo Angelucci and Peter Bowers, Orion Books, 1987
E-mail from Gerald Balzer on myth of the XP-79B being intended to ram enemy aircraft.
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