In 1943 Luftwaffe air superiority was being challenged by the Allies over the Reich and radical innovations were required to overcome the crisis. Surface-to-air missiles appeared to be a promising approach to counter the Allied strategic bombing offensive; a variety of projects were started, but invariably problems with the guidance and homing systems prevented any of these from attaining operational status.[2] Providing the missile with a pilot, who could operate a weapon during the brief terminal approach phase, offered a solution.