7

The Wikipedia article cited in another answer lists among reasons ...equipment, like that of the Red Army, was largely obsolescent and suffering from prolonged use. The Great Purges had also hit aircraft manufacturers, and the loss of personnel ended the Soviet lead in aircraft design and aeronautics (...) The aviation industry was disrupted, ...


4

Organizational deficiencies, technical obsolescence, inexperience of pilots, surprise caused by Stalin's blunder First of all, claim that VSS lost 4000 planes in first three days of war is somewhat dubious. This is mostly based on German sources, which is understandable since Soviet usually omitted exact data from this embarrassing period . Only recently ...


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