HMS X9 (Pluto) was a British X-class midget submarine built during World War II for the Royal Navy's special operations against major German warships. She was one of the famous "X-Craft" submarines designed to carry large explosive charges beneath enemy ships.
Design and Role
The X-class submarines were very small vessels, about 15.6 metres (51 ft) long, with a crew of four. Rather than carrying torpedoes, they carried two large detachable explosive charges that could be placed beneath an enemy warship before the submarine escaped.
Because of their limited range, X-Craft were normally towed by larger Royal Navy submarines close to their target area.
Operation Source
In September 1943, HMS X9 was assigned to Operation Source, one of the Royal Navy's boldest special operations of the war. The mission aimed to attack major German warships in Norwegian fjords, including the battleships Tirpitz and Scharnhorst. [Six X-Craft took part:
- X5, X6 and X7 were assigned against Tirpitz.
- X8 was assigned against Lützow.
- X9 and X10 were intended to attack Scharnhorst.
- Loss of HMS X9
HMS X9 never reached Norway. On 16 September 1943, while under tow across the North Sea, the towing cable parted. The midget submarine disappeared and sank with her crew. There were no survivors. Investigations later suggested that after the tow broke, X9 may have become trimmed down by the bow and been dragged under by the weight of the waterlogged tow cable.
The three men officially recorded as lost were:
- Sub-Lieutenant Edward Kearon
- Able Seaman Harry Albert Harte
- Stoker George Henry Hollett
Legacy
Although HMS X9 was lost before reaching her target, Operation Source succeeded in severely damaging the German battleship Tirpitz, keeping her out of action for many months and reducing the threat she posed to Allied Arctic convoys. The sacrifice of the crews of X-Craft such as X9 formed an important part of that success.
The unofficial name often associated with X9 was "Pluto."