The Bell P-39K-1 Airacobra was an American single-engine fighter produced by Bell Aircraft. It stood out for its innovative features, including tricycle landing gear and an engine mounted behind the cockpit that drove a propeller at the front of the aircraft. The P-39K-1 was developed from the P-39D-2 and featured strengthened nose landing gear which otherwise tended to fail during high-speed landings. Due to its poor high-altitude performance, however, the P-39 fighter never found success in British service. In the Pacific, it was primarily used for troop support. The aircraft achieved its greatest success on the Eastern Front with Soviet pilots because combat conditions there better suited its strengths. There were 210 P-39Ks built, but the exact number of this variant sent to the USSR is unknown.

The Soviet P-39K-1 has been in the game since the beginning of the Open Beta Test prior to Update 1.27. In combat, the aircraft stands out primarily for its speed in level flight and dives. Its turning performance is unremarkable, but it can compete with most opponents when the flaps are used properly, with the notable exception of many Japanese and British fighters. The aircraft also benefits from effective offensive armament and good protection, allowing it to engage larger aircraft with relative confidence. However, its main drawbacks include poor high-altitude engine performance, challenging 37 mm cannon ballistics, and vulnerable fuel tank placement.