Northrop XP-79

XP-79

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

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]

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 cancelled.

Specifications (XP-79B)

Data from

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

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)

References

Notes

↑ Winchester 2005, p. 150.
↑ Winchester 2005, p. 151.

Bibliography

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

Wikimedia Commons has media related to Northrop XP-79.

Northrop aircraft

Manufacturer
designations

'Greek' series	Alpha Beta Gamma Delta

'N' series	Note: Northrop company designations include a wide variety of technologies. Only aircraft, aero engines, and missiles are linked here. N-1 N-2 N-3 N-4 N-5 N-6 N-7 N-8 N-9 N-10 N-12 N-14 N-15 N-16 N-18 N-19 N-20 N-21 N-23 N-24 N-25A N-25B N-26 N-29 N-31 N-32 N-34 N-35 N-36 N-37 N-38 N-39 N-40 N-41 N-45 N-46 N-47 N-48 N-49 N-50 N-51 N-52 N-54 N-55 N-59 N-60 N-63 N-65 N-67 N-68 N-69 N-71 N-72 N-73 N-74 N-81 N-82 N-84 N-86 N-87 N-94 N-96 N-102 N-103 N-105 N-110 N-111 N-112 N-117 N-124 N-132 N-133 N-134 N-135 N-138 N-141 N-144 N-149 N-150 N-151 N-155 N-156 N-165 N-204 N-205 N-250 N-267 N-285 N-300 N-301 N-302 N-303 N-304 N-305 N-306 N-307 N-311 N-320 N-321 N-322 N-330 N-370

'P' series	P530 P600 P610 P630

By role

Attack	YA-13 XA-16 A-17 Nomad YA-9

Bombers	YB-35 YB-49 B-62 BT B2T B-2

Drones	Q-4

Fighters	3A XP-56 P-61 XP-79 F-89 XFT F2T F-5/CF-5/CF-116 YF-17 F-18L F-20 YF-23

Reconnaissance	F-15 RF-61 RF-5 N-165 N-204

Trainers	T-38

Transports	Alpha Beta Gamma Delta C-19 C-100 YC-125 RT

Experimental	N-1M N-9M JB-1 MX-324 MX-334 M2-F2 M2-F3 HL-10 Tacit Blue X-4 X-21

Names

USAAS/USAAC/USAAF/USAF fighter designations 1924–1962

Pursuit (pre-1948) Fighter (post-1948)	P-1 P-2 P-3 XP-4 P-5 P-6 XP-7 XP-8 XP-9 XP-10 P-11 P-12 XP-13 XP-14 XP-15 P-16 P-17 YP-18 YP-19 YP-20 P-21 XP-22 P-23 YP-24 P-25 P-26 P-27 P-28 P-29 P-30 XP-31 P-32 P-33 XP-34 P-35 P-36 P-37 P-38 P-39 P-40 XP-41 P-42 P-43 P-44 P-45 XP-46 P-47 XP-48 XP-49 XP-50 P-51 XP-52 P-53 XP-54 XP-55 XP-56 XP-57 XP-58 P-59 P-60 P-61/C XP-62 P-63 P-64 P-65 P-66 XP-67 XP-68 P-69 P-70 XP-71 XP-72 P-73 P-74¹ P-75 XP-76 XP-77 P-78 XP-79 P-80 XP-81 F-82 XP-83 F-84 F-85 F-86/D XF-87 F-88 F-89 XF-90 XF-91 XF-92 YF-93 F-94 F-95 F-96 F-97 F-98 F-99 F-100 F-101 F-102 XF-103 F-104 F-105 F-106 F-107 XF-108 XF-109 F-110 F-111/B

Pursuit, Biplace	PB-1 PB-2 PB-3

Fighter, Multiplace	FM-1 FM-2

¹ Not assigned See also: F-24 • F-117 • P-400 • post-1962 sequence