HMS L10

HMS L10 was a British L class submarine commissioned in June 1918 and destroyed by enemy action in October of the same year. Built at Dumbarton by William Denny, "L10" was a modern and advanced boat with 4 torpedo tubes and one 4" gun. She was assigned to serve in the North Sea against German surface units counteracting German efforts to sow mines in British waters.

Her greatest success was the classic example of a pyrrhic victory, when on the morning of the 4 October, 1918, aged just under four months, the "L10" surfaced in the Heligoland Bight with the mission of intercepting a German raiding party. This group, consisting of the destroyers SMS S34, SMS S33, SMS V28 and SMS V29 had been delayed in the Bight because the "S34" had detonated a mine. The other destroyers were crowded round their damaged comrade, and so it was easy for "L10"'s commander, Alfred Edward Whithouse to sneak into position and put a torpedo into the "S33", which rapidly began to sink. Unfortunately, as she fired, the "L10" rose suddenly to the surface and was seen instantly by the "V28" and "V29". Although she turned and tried to flee, "L10" was not fast enough to escape her pursuers and was rapidly chased down and sunk with all hands. She was the only L class boat to be lost during the First World War.