The Bell P-63 Kingcobra was created as an improved version of the earlier P-39 Airacobra, with production examples being delivered from October 1943. The first production model of the P-63 was the P-63A.
It quickly became clear that the P-63 was not advanced enough for front line service, resulting in 2,421 of the more than 3,300 produced being supplied to the Soviet Union under the Lend-Lease scheme, while at least 300 other examples were passed to the Free French.
The P-63, like its P-39 predecessor, had its engine mounted behind the cockput and a tricycle landing gear. This proved to be one of the more distinctive features of the aircraft but also caused problems. For one, the mass of the engine being placed behind the cockpit made flat spins especially more common, so caution was advised during even the simplest maneuvers.
The first variants of the P-63 series were the various sub-variants of the first P-63A model. These included such models as the A-5 to A-10. However, these were typically small variants with few changes to design or armament. The next major variant was the P-63C, featuring an Allison V-1710-117 engine, more armour, extra fuel and - from the P-63C-5-BE - a long ventral fin extending from near the trailing edge of the wing to the rear of the rudder.
Many of the 1,227 P-63Cs produced went to the Soviet Union, and were delivered with unchanged armament, the Soviets removing the podded .50 guns on arrival. P-63s sent to the Soviets were delivered in Olive Drab and Neutral Gray camouflage. Like the A series, several sub variants and changes were made during the production. Following the C model was a series of examples that would not be counted as official series variants because only one to two models of each were produced.
The original Army order for the XP-63 was issued on 27 June 1941, and consisted of specifications for two aircraft, the first of which was ready for flight on 7 December 1942. Equipped with the Allison V-1710-47 engine of the XP-39E and the armament of the P-39Q, the first aircraft was soon destroyed in a crash, followed by the second which was lost barely 3 months after its first flight on 5 February 1943. The loss of both prototypes led to flight testing being completed with the XP-63A ordered during June 1942, which made its initial flight on 26 April 1943.
According to the test pilots, the new fighter handled well with no bad flying characteristics, and had improved performance compared to the P-39. Unfortunately, the improvement was not sufficient to enable P-63s to operate against up to date fighters such as the Focke Wulf Fw 190. It was therefore decided to supply P-63s to the Soviet Union via the Alaska ferry route, to supplement the P-39s which were already being delivered.
A considerable number of P-63s were retained in the US for use by the Army Air Corps. Some were used as base hacks or sent to advanced training units, but the majority were adapted to serve as live targets for aerial gunnery practice. These aircraft, known as RP-63s, were gutted of armament and armour, before being fitted with an extra thick skin weighing 680 kilograms.
This was placed over vital areas of the airframe, and fitted with sensors connected - via a cockpit control board - to the landing lights and extra lights added to the airframe, which would light up when the skin was hit by splinters from frangible bullets used for training. The dorsal intake was replaced with a clam shell unit, part of the cockpit canopy was covered over, and the modified aircraft were painted in a variety of bright colours. The initial five RP-63A-11s - based on the P-63A-9 - were followed by 89 RP-63A-12s with increased fuel tankage of 126 gallons, 200 RP-63Cs with V-1710-117 and 32 RP-63Gs.
In actual combat meanwhile, the Soviet Union was the chief operator of the P-63. In total, some 2,300 examples were delivered to the Soviet Union by war's end. According to the Lend Lease agreement however, it was stated that the Soviet Union was not allowed to use P-63 King Cobras on the Eastern Front against Germany. However, there are reports from both German and Soviet sources stating that a number of P-63s were diverted to fight on the Eastern Front and did indeed see combat against German troops. It is known for certain, however, that the P-63 was used in the Far Eastern Asia Front against Japan during the last days of the war following the Soviet Union's declaration of war in 1945.
- O'leary, Michael USAAF Fighters of World War Two in Action. Blandford Press. 1986. Page 379 ISBN 0-7137-1839-0 Cite error: Invalid
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- "Aircraft of the World Card Collection Group 11 Card 30"
- O'Leary, Michael. Page 369
- O'Leary, Michael. Page 371
- O'Leary, Michael. Pages 361-362
- O'Leary, Michael. Page 375