primary operation was to attack the German battleship Tirpitz, which was 'holed up' in Alten Fjord, Norway. By September 1943, the six X5 Class midget submarines and their hand-picked, highly-trained crews were ready to undertake a mission that was to write a chapter in the history of submarine warfare.
With engines that generated 42 hp (surfaced) and only 30 hp (submerged), the X-craft were too small to undertake long passages and were, therefore, always towed to their target area by full-sized submarines, at maximum speeds of 10.5 knots (surfaced) and 12 knots (submerged). As can be expected, towing midgets reduced the endurance of submarines - the S Class, for example, had a 30 per cent reduction in endurance, and the comparable figure for the larger T Class was around 50 per cent.
