The Curtiss XP-31 Swift (Wright Field Project Number XP-934) was a 1930s American

experimental An experiment is a procedure carried out to support or refute a hypothesis, or determine the efficacy or likelihood of something previously untried. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs whe ...

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings. A monoplane has inherently the highest efficiency and lowest drag of any wing con ...

fighter built by Curtiss for the

United States Army Air Corps The United States Army Air Corps (USAAC) was the aerial warfare service component of the United States Army between 1926 and 1941. After World War I, as early aviation became an increasingly important part of modern warfare, a philosophical ri ...

. The XP-31 featured the first enclosed cockpit on a U.S. pursuit aircraft and was also the last pursuit aircraft to have fixed landing gear and externally braced wings. Despite its innovations, the XP-31 did not offer any advantages compared to its rival the

Boeing P-26 Peashooter The Boeing P-26 "Peashooter" is the first American production all-metal fighter aircraft and the first pursuit monoplane to enter squadron service with the United States Army Air Corps. Designed and built by Boeing, the prototype first flew in 1 ...

and was not ordered into series production.

Design and development

Curtiss offered the XP-31 (given the Wright Field Project Number XP-934) in a 1932 competition with the P-26. It was a low-wing monoplane with fixed landing gear, first flown in July. It was the AAC's first single-seat closed-cockpit fighter, and the last with fixed gear and wing struts. Despite its small size, it was badly overweight, and carried 125 gallons (104 imp gal, 474 L) of fuel. Although Curtiss considered the design significant in that it introduced various new technologies, compared to its contemporaries the XP-31 was already outmoded, and, more importantly, testing showed that it fell below performance expectations.

Testing and evaluation

Curtiss XP-31 with Wright R-1820 060907-F-1234P-010

leading edge slot A leading-edge slot is a fixed aerodynamics, aerodynamic feature of the wing of some aircraft to reduce the Stall (flight), stall speed and promote good low-speed handling qualities. A leading-edge slot is a spanwise gap in each wing, allowing ai ...

s and large trailing-edge flaps, so a 600 hp (450 kW) Curtiss V-1570 Conqueror was substituted. In this form, the Curtiss XP-31 Swift (s/n 33-178) was delivered on 1 March 1933, having already lost to the P-26. The sole example was scrapped in 1935.Dorr and Donald 1990, p. 60.

Operators

; *

Specifications

References

;Notes ;Bibliography * Bowers, Peter M. ''Curtiss Aircraft 1907-1947''. London: Putnam & Company Ltd., 1979. . * Donald, David, ed. ''Encyclopedia of World Aircraft''. Etobicoke, Ontario, Canada: Prospero Books, 1997. . * Dorr, Robert F. and David Donald. ''Fighters of the United States Air Force''. London: Aerospace Publishing, 1990. . * Green, William and Gordon Swanborough. ''The Complete Book of Fighters''. New York: Smithmark, 1994. . * Jones, Lloyd S. ''U.S. Fighters: Army-Air Force 1925 to 1980s''. Fallbrook, California: Aero Publishers, 1975. . * ''Pedigree of Champions: Boeing Since 1916, Third Edition''. Seattle, Washington: The Boeing Company, 1969.

External links

{{Wright Field project numbers Curtiss P-31 P-31 Swift Single-engined tractor aircraft Low-wing aircraft Aircraft first flown in 1932 Aircraft with fixed conventional landing gear