Love how those early MiGs (and the F-86) are basically a jet engine with wings
By 1946, Soviet designers were finding it impossible to perfect the German-designed HeS-011 axial-flow jet engine, and new airframe designs from Mikoyan were threatening to outstrip development of the engines to power them. Soviet aviation minister Mikhail Khrunichev and aircraft designer A. S. Yakovlev suggested to Premier Joseph Stalin the USSR buy advanced jet engines from the British. Stalin is said to have replied, "What fool will sell us his secrets?"
However, he gave his consent to the proposal and Mikoyan, engine designer Vladimir Klimov, and others travelled to the United Kingdom to request the engines. To Stalin's amazement, the British Labour government and its pro-Soviet Minister of Trade, Sir Stafford Cripps, were perfectly willing to provide technical information and a license to manufacture the Rolls-Royce Nene. This engine was reverse-engineered and produced as the Klimov RD-45, subsequently incorporated into the MiG-15. Rolls-Royce later attempted to claim £207 million in license fees, without success.