The Junkers Ju 87 Stuka made its combat debut in 1937 with the Luftwaffe's Condor Legion during the Spanish Civil War and served the Axis forces in World War II. It was noted for its wailing sirens which were the propaganda symbol of German blitzkrieg victories of 1939-1942. The Stuka's design included several innovations, including automatic pull-up dive brakes under both wings to ensure that the aircraft recovered from its attack dive even if the pilot blacked out from the high g-forces.