In 1936, he graduated from the military school of pilots and became a pilot within the Red Air Force. He later served as a junior pilot within th Air Force of the Belarusian Military District. From March 1938 to August 1938, Bobrov fought in the Spanish Civil War as a foreign volunteer for the Republican Government. Flying Polikarpov I-16 with the Republican Air Force, he was credited with 13 solo and 4 shared aerial victories against Aviación Nacional, while flying 126 missions, which includes 47 dogfights. After his return to USSR, he flew missions during the Winter War. He later served in the 4th and 10th Fighter Aviation Regiments. In 1941 he graduated from the Lipetsk higher aviation advanced training courses for squadron commanders. On the same year, he joined the Communist Party of Soviet Union.