Complex sentence: One of his tasks was to study the possibility of developing a medium-range winged rocket, but when Hitler launched Operation Barbarossa in 1941 and rapidly overran the Soviet front-line forces, the Academy's staff was evacuated to Sverdlovsk in the Urals.
Split into simpler sentences: One of his tasks was to study the possibility of developing a medium-range winged rocket. The Academy's staff was evacuated to Sverdlovsk in the Urals.