As was the case in many other fields of advanced experimentation, the Germans only toyed with adapting rockets for launch from a submerged U-boat. It was an idea that was tremendously ahead of its time, as neither the U-boat nor the rocket had at that stage reached the capabilities they would later. Yet, as was the case in other areas, the experimenters did not lack for imagination and in the process set the pattern for weapons that would come into use decades later. The idea of rocket-firing U-boats came into existence because of a lucky coincidence. It happened that Kvtkpt. Fritz Steinhoff, captain of U-551, had a brother, Dr. Ernst Steinhoff, who was working on small rocket guidance at Peenemunde. After much discussion, they became convinced of the practicality of the idea of mating their two lines of endeavour. During the summer of 1942, U-551 had a rack for six 30-cm rockets installed, and considerable “unofficial” testing was carried out. These concluded with the successful launch of a rocket from a depth of 12 meters. Yet they were unable to interest anyone on Donitz’s staff and the idea died for lack of official support. During 1943, the idea arose to launch A-4 (V-2) missiles from submarine carried, watertight launch containers. A contract for three such containers was given to a Stettin shipyard in December 1944, but none had been completed at war’s end. Two photographs below showing the Installation and testing of rocket equipment on U-551. All the equipment is Army-issue, 30cm Wurfkorper 42 Spreng rockets then under development, firing from a Schweres Wurfgerat 41 launcher. The rocket was an unguided saturation-type weapon. The technology that would allow successful submarine launched tactical missiles was still 30 years In the future.