This is a cut and paste from the Wikipedia entry for Pokryshkin. It states what I have long suspected, that the Soviets used the p-63 in the eastern front, then covered it up for political reasons. Is this just conjecture, or is there any proof?
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Pokryshkin and his regiment have repeatedly been asked to convert to new Soviet fighters such as the
La-5 and
Alexander Sergeyevich Yakovlev's Yak fighter series. However Pokryshkin found La-5's firepower insufficient and personally disliked Yakovlev so he never did.
Finally in 1944 he found an aircraft that he was willing to convert to, Lavochkin
La-7. Unfortunately one of his close friends, Soviet 50-kill (31 personal and 19 group ) ace Alexander Klubov was killed in a landing mishap while converting to the La-7. The crash was blamed on the malfunction of the plane's hydraulic system. Pokryshkin subsequently cancelled his regiment's conversion, and there are multiple reports that they instead began flying Bell
P-63 Supercobras. By the lend-lease agreement with United States the Soviet Union was not allowed to use P-63s against Germany; they were given only to be used in the eventual battle with Japan. Thus it is quite understandable that no mention of this appears in any official records. However personal accounts of German pilots and flak crewmen who encountered P-63s in the skies of Eastern Prussia as well as the memoirs of one of the pilots in Pokryshkin's squadron appear to confirm that fact.
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