The Bell P-39 was an unusual fighter at the time, the engine was placed in the center of the aircraft for a good weight-ratio. This was not unique but at the least unusual.

The P-39 Airacobra had a tricycle landing gear, which was the first such gear ever used on a production fighter. The Airacobra battled throughout the world, particularly in the Southwest Pacific, Mediterranean and Russian theaters. Because its engine was not equipped with a supercharger, the P-39 performed best below 17,000 feet (5,200 m) altitude.

The P-39 often was used at lower altitudes for such missions as ground strafing. Same with the P-63 Kingcobra, the P-39 aircraft was considered to be the most victorious mass-produced, fixed-wing aircraft manufactured by Bell Aircraft Corporation. Primarily used by the U.S Army Air Force

• – The prototype XP-39 flew for the first time on April 6th 1938 powered by an Allison V-1710-17 12 Cylinder liquid-cooled engine providing 1150 Hp.
• – The next step was the YP-39 of which 13 were produced for service evaluation. The YP-39 was mounted with an 37 mm M4 Cannon, two fuselage mounted 12,7 mm guns and two wing-mounted 7,62 mm guns.
• – The initial production model (P-39C) was similar to the YP-39 and 20 were built.
• – Adding self sealing fuel-tanks and two additional 7,62 mm machine guns in the wings resulted in the P-39D witch entered service to the USAAC in February 1941.
• – The P-39-1 replaced the 37 mm M4 cannon with a 20 mm M1 cannon.
• – After that the P-39D-2 replaced the 1150 Hp V-1710-35 with a 1325 Hp V-1710-63 engine.
• – There were three examples built with laminar-flow wings (XP-39E)
• – The P-39F was basically a P-39D with minor upgrades.
• – Only 25 Airacobra’s were built with a 1100 Hp engine (V-1710-59 by Allison) designated P-39J.
• – P-39K: was also basically a P-39D-2 but with a different propeller
• – P-39L: Also a P-39D-2 only with a different nose-wheel
• – In November 1942 the first P-39M began to appear, it had a 1200 Hp V-1710-83 engine.
• – P-39N: This was the first Airacobra built in large numbers, it had a 1200 Hp V-1710-85 engine, and 2095 were built.
• – The final subtype of the P-39, the P-39Q had the wing-mounted 7,62 mm machine guns deleted, and a 12,7 mm gun mounted beneath each mainplane. The P-39Q was built in the largest numbers, at total of 4905 P-39Q’s left the factories.

Totally a number of 9558 P-39 of all types were produced.

All pictures courtesy of Zijde Aviation Photo and Publishing, Rob Vogelaar / Marcel van Leeuwen