Although the rapid industrialization the Soviet Union experienced in the 1930s had the potential to enable the Soviet Air Forces to be effective against the Luftwaffe , Stalin 's purges left the organization weakened . However , when Germany invaded in June 1941 , the size of the Soviet Air Forces allowed it to absorb horrendous casualties and still maintain capability . Despite the near collapse of Soviet forces in 1941 , they survived , as German forces outran their supply lines and the Americans and British provided Lend Lease assistance
Stalin 's purges
Great Purge
History of aerial warfare