P-39
The Bell P-39 Airacobra was one of the principal American fighter aircraft in service at the start of World War II. Although its mid-engine placement was innovative, the P-39 design was handicapped by the lack of an efficient turbo-supercharger, limiting it to low-altitude work, although the type was used with great success by the Soviet Air Force. In the P-39, Soviet pilots scored the highest number of individual kills attributed to any U.S. fighter type.
The P-39 was an all-metal, low-wing, single-engine fighter, with tricycle undercarriage incorporating a very streamlined and aerodynamically efficient design.