U-234, a minelaying U-boat, left Germany on 5 April 1945, her mine-storage areas full of material for Japan. The 12 passengers included the new air attaché to Tokyo, General of the Air Force Ulrich Kessler, who had directed the air attack on Poland in 1935 and was implicated in a plot against Hitler in 1944. Accompanying the general were two military advisors1st Lt Erich Menzel, a radar specialist, and Lt Col Fritz von Sandrart, an expert in antiaircraft defense strategy. Gerhard Falcke, a naval construction expert with diplomatic experience, headed the naval contingent. Heinrich Hellendorn, a naval antiaircraft specialist, was studying the Imperial Navys tactics at sea. Richard Bulla, a naval aviator, had been sent to observe Japanese carrierborne naval aviation. Naval judge Kay Nieschiling was to be the judicial officer in charge of military justice for the two thousand German naval personnel in Japan. Dr. Heinz Schlicke, one of Germanys leading electronics experts, was to help Japan develop new radar and countermeasures systems. August Bringewald, who headed a two-man Messerschmitt contingent, was in charge of ME-262 jet-fighter production. Franz Ruf, an industrial machinery specialist, was to help the Japanese build new aircraft factories. Also on board were two Japanese officers, Lt Comdr Tomonaga Hideo, a naval aviator and submarine specialist, and Lt Shoji Genzo. The mission of these men, both of whom had served as attachés at several Japanese embassies in Europe, was to make sure the material arrived in Japan.