The Bell P-39 Airacobra was an American military fighter with its engine mounted behind the pilot. A long shaft drove the propeller, leaving the nose available for a heavy cannon. It was among the Army's frontline fighters when the United States entered the Second World War and became an important Lend-Lease aircraft.[1]Bell P-39Q AiracobraNational Air and Space Museum · airandspace.si.edu · Accessed 2026-09-13Open source details[2]Bell P-39Q AiracobraNational Museum of the United States Air Force · nationalmuseum.af.mil · Accessed 2026-09-13Open source details
Design origins
Bell engineer Robert Woods developed the design around a 37 mm cannon and the Army Air Corps' 1937 fighter requirements. The Army ordered the XP-39 prototype in October 1937, and it first flew in April 1939. Heavy armament, visibility and ground handling were central design considerations.[1]Bell P-39Q AiracobraNational Air and Space Museum · airandspace.si.edu · Accessed 2026-09-13Open source details[2]Bell P-39Q AiracobraNational Museum of the United States Air Force · nationalmuseum.af.mil · Accessed 2026-09-13Open source details
Production Airacobras used the Allison V-1710 engine. The P-39Q combined its cannon with machine guns in the nose and underwing pods. The arrangement gave it considerable firepower within a relatively compact single-engine airframe.[2]Bell P-39Q AiracobraNational Museum of the United States Air Force · nationalmuseum.af.mil · Accessed 2026-09-13Open source details
Wartime operations
Airacobras fought in the Southwest Pacific, Mediterranean and Soviet theatres. Aircraft diverted from British orders also entered American service as P-400s. American units used them from Port Moresby, New Guinea, during the difficult early fighting against Japanese forces.[1]Bell P-39Q AiracobraNational Air and Space Museum · airandspace.si.edu · Accessed 2026-09-13Open source details
The type also operated in Alaska. During 1942, the 57th Fighter Squadron flew from Adak against Japanese-held islands, contending with fog, storms and difficult flying conditions as well as enemy opposition.[2]Bell P-39Q AiracobraNational Museum of the United States Air Force · nationalmuseum.af.mil · Accessed 2026-09-13Open source details
Production and training
Bell manufactured 9,584 Airacobras before production ended in August 1944. Nearly half went to the Soviet Union, making the aircraft a major element of wartime aircraft supply rather than simply an American domestic fighter.[2]Bell P-39Q AiracobraNational Museum of the United States Air Force · nationalmuseum.af.mil · Accessed 2026-09-13Open source details
The Smithsonian's P-39Q served with replacement training units instead of seeing combat. Its assignments included several Washington State airfields during 1944. This surviving aircraft records the training system that prepared pilots for a design whose unusual engine position and handling required familiarisation.[1]Bell P-39Q AiracobraNational Air and Space Museum · airandspace.si.edu · Accessed 2026-09-13Open source details