The Bell XP-83 (later redesignated ZXF-83) was a United States prototype jet

escort fighter The escort fighter was a concept for a fighter aircraft designed to escort bombers to and from their targets. An escort fighter needed range long enough to reach the target, loiter over it for the duration of the raid to defend the bombers, and ...

Bell Aircraft The Bell Aircraft Corporation was an American aircraft manufacturer, a builder of several types of fighter aircraft for World War II but most famous for the Bell X-1, the first supersonic aircraft, and for the development and production of man ...

during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...

. It first flew in 1945. As with most early first generation jet fighters, the design was hampered by a relative lack of power. With the rapid advancements in jet technology post-WWII, the XP-83 was soon eclipsed by more advanced designs and it never entered production.

Design and development

The early jet fighters consumed fuel at a prodigious rate which severely limited their

range Range may refer to: Geography * Range (geographic), a chain of hills or mountains; a somewhat linear, complex mountainous or hilly area (cordillera, sierra) ** Mountain range, a group of mountains bordered by lowlands * Range, a term used to i ...

and

endurance Endurance (also related to sufferance, resilience, constitution, fortitude, and hardiness) is the ability of an organism to exert itself and remain active for a long period of time, as well as its ability to resist, withstand, recover from an ...

. In March 1944, the

United States Army Air Forces The United States Army Air Forces (USAAF or AAF) was the major land-based aerial warfare service component of the United States Army and ''de facto'' aerial warfare service branch of the United States during and immediately after World War II ...

requested Bell to design a fighter with increased endurance and formally awarded a contract for two prototypes on 31 July 1944. Bell had been working on its "Model 40" interceptor design since 1943. It was redesigned as a long-range escort fighter while retaining the general layout of the

P-59 Airacomet The Bell P-59 Airacomet was a single-seat, twin jet-engine fighter aircraft that was designed and built by Bell Aircraft during World War II, the first produced in the United States. As the British were further along in jet engine develop ...

. The two General Electric J33-GE-5

turbojet The turbojet is an airbreathing jet engine which is typically used in aircraft. It consists of a gas turbine with a propelling nozzle. The gas turbine has an air inlet which includes inlet guide vanes, a compressor, a combustion chamber, an ...

engines were located in each wing root which left the large and bulky

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraf ...

free for fuel tanks and armament. The fuselage was an all-metal

semimonocoque The term semi-monocoque or semimonocoque refers to a stressed shell structure that is similar to a true monocoque, but which derives at least some of its strength from conventional reinforcement. Semi-monocoque construction is used for, among ot ...

capable of carrying 1,150 gal (4,350 L) of fuel. In addition, two 250 gal (950 L)

drop tank In aviation, a drop tank (external tank, wing tank or belly tank) is used to describe auxiliary fuel tanks externally carried by aircraft. A drop tank is expendable and often capable of being jettisoned. External tanks are commonplace on modern ...

s could be carried. The cabin was

pressurized {{Wiktionary Pressurization or pressurisation is the application of pressure in a given situation or environment. Industrial Industrial equipment is often maintained at pressures above or below atmospheric. Atmospheric This is the process by ...

and used a small and low bubble style canopy. The armament was to be six 0.5 in (12.7 mm)

machine gun A machine gun is a fully automatic, rifled autoloading firearm designed for sustained direct fire with rifle cartridges. Other automatic firearms such as automatic shotguns and automatic rifles (including assault rifles and battle rifles) ar ...

s in the nose.

Testing

Early wind tunnel reports had pinpointed directional instability but the "fix" of a larger

tail The tail is the section at the rear end of certain kinds of animals’ bodies; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammal ...

would not be ready in time for flight testing. The first prototype was flown on 25 February 1945, by Bell's chief test pilot, Jack Woolams, who found it to be under-powered and unstable. The limited flight testing provided satisfactory flight characteristics although spins were restricted until the larger tail fin was installed. The second prototype did incorporate the extended tail and an aileron boost system. One unique characteristic was the XP-83's refusal to slow down due to its sleek aerodynamic shape and lack of drag brakes. This meant that test pilots were forced to fly "stabilized approaches" (i.e. very long and flat landing approaches).Koehnen 1982, p. 48. The first prototype was used in 1946 as a

ramjet A ramjet, or athodyd (aero thermodynamic duct), is a form of airbreathing jet engine that uses the forward motion of the engine to produce thrust. Since it produces no thrust when stationary (no ram air) ramjet-powered vehicles require an as ...

test-bed with an engineer's station located in the fuselage behind the pilot. On 14 September 1946, one of the ramjets caught fire forcing pilot, "Slick" Goodlin and engineer Charles Fay, to bail out. The second prototype flew on 19 October and was later scrapped in 1947. Apart from range, the XP-83 was inferior to the

Lockheed P-80 Shooting Star The Lockheed P-80 Shooting Star was the first jet fighter used operationally by the United States Army Air Forces (USAAF) during World War II. Designed and built by Lockheed in 1943 and delivered just 143 days from the start of design, prod ...

and this led to the cancellation of the XP-83 project in 1947.

Specifications (XP-83)

References

Notes

Bibliography

* Carpenter, David M. ''Flame Powered: The Bell XP-59A Airacomet and the General Electric I-A Engine''. Boston: Jet Pioneers of America, 1982. . (Page 59 is about the XP-83.) * Green, William. ''War Planes of the Second World War: Fighters, Volume Four''. London: Macdonald, 1961 (6th impression 1969). . * Green, William and Gordon Swanborough. ''WW2 Aircraft Fact Files: US Army Air Force Fighters, Part 1''. London: Macdonald and Jane's Publishers Ltd., 1977. . * Knaack, Marcelle Size. ''Encyclopedia of US Air Force Aircraft and Missile Systems: Volume 1 Post-World War II Fighters 1945-1973''. Washington, DC: Office of Air Force History, 1978. . * Koehnen, Richard C. "Bell's No Name Fighter." ''Airpower'', Vol. 12, no. 1. January 1982. * Pelletier, Alain J. ''Bell Aircraft Since 1935''. Annapolis, MD: Naval Institute Press, 1992. .

External links

Joe Baugher's XP-83 page

USAF Museum page

{{USAF fighters P-083 Bell P-83 Twinjets Cancelled military aircraft projects of the United States Aircraft first flown in 1945 World War II jet aircraft of the United States Mid-wing aircraft