Bell P-39N Airacobra
The P-39 was an unusual design when it appeared in 1937. Among its many unorthodox design features are the mounting of the engine behind the pilot, the use of automobile type doors on the sides of the cockpit, and tricycle landing gear. The Airacobra had good low altitude performance but suffered badly at high altitudes. Fortunately, the aircraft’s large, nose mounted 37mm cannon made it a perfect ground attack aircraft. Large numbers of P-39s were exported to the Soviet Union where they were very popular in this role. The Airacobra was never popular in American or British service, but they still served in combat during the early stages of the war while more capable types were being designed and built.