HMS L11

HMS L11 was a L-class submarine built for the Royal Navy during World War I. She was one of five boats in the class to be fitted as a minelayer. The boat survived the war and was sold for scrap in 1932.

Design and description
L9 and its successors were enlarged to accommodate 21-inch (53.3 cm) torpedoes and more fuel. The submarine had a length of 238 ft overall, a beam of 23 ft and a mean draft of 13 ft. They displaced 914 LT on the surface and 1089 LT submerged. The L-class submarines had a crew of 38 officers and ratings.

For surface running, the boats were powered by two 12-cylinder Vickers 1200 bhp diesel engines, each driving one propeller shaft. When submerged each propeller was driven by a 600 hp electric motor. They could reach 17 kn on the surface and 10.5 kn underwater. On the surface, the L class had a range of 3800 nmi at 10 kn.

The boats were armed with four 21-inch torpedo tubes in the bow and two 18-inch (45 cm) in broadside mounts. They carried four reload torpedoes for the 21-inch tubes for a grand total of ten torpedoes of all sizes. They were also armed with a 4 in deck gun. L11 was fitted with 16 vertical mine chutes in her saddle tanks and carried one mine per chute.

Construction and career
L11 was built by Vickers, Barrow. She was laid down on 17 January 1917 and was commissioned on 27 June 1918. The boat was sold for scrap in February 1932.