The British L class submarine were originally planned under the emergency war programme as an improved version of the British E class submarine. The scale of change allowed the L class to become a separate class. The introduction of the L class came too late to contribute significantly in World War I. L2 was accidentally depth-charged by three American destroyers in early 1918. L12 torpedoed the German submarine UB-90. L10 torpedoed the German destroyer S33 in October 1918 but was sunk by accompanying destroyers.