The value of tactical dive bombing had been proven by the Junkers Ju 87 "Stuka" dive bombers of the "Luftwaffe" during the Blitzkrieg campaigns of 1939 and 1940, and the need for such an aircraft in the VVS-RKKA (Workers &amp; Peasants' Red Army Air Force) suddenly became very apparent. Furthermore, following the Molotov–Ribbentrop Non-Aggression Pact, Soviet experts were able to visit German aircraft factories, where they discovered that Germany had no large-scale development of high-altitude long-range bombers underway. Existing aircraft were also judged to be within the capabilities of single-engined fighters like the I-200.