Part one of term paper
The pre-war issue torpedo had the disadvantage of leaving a visible trail of bubbles on the surface on its way to the target. The standard torpedo of the war suffered from early problems with its internal depth-keeping equipment, and its firing pistol, but these were solved after the Norwegian Campaign. In mid 1942 an improved version was i ...

Part two of term paper
... which was faster, had a greater range and could be used with either magnetic or contact detonators. The Zaunköning (Gnat) came into service during the autumn of 1943. Intended to be an escort-killer, it achieved some early minor success only to be countered by the allied Foxer noise-making decoy. It was scoring hits against escort and merchants to the end of the war though. The weapon was designed to lock onto the loudest noise after a run of 400m from its launch. This often proved to be the U- ...