K-class Submarine

A class of steam-turbine-powered Royal Navy submarines of the First World War, designed for 24-knot surface speed to operate with the battle fleet. Their oil-fired boilers and funnels gave a long dive sequence and a low forward freeboard that made them prone to accidents; the class earned the nickname “Kalamity class.” Eight K-boats were involved in the “Battle of May Island” on 31 January 1918 off the Firth of Forth, a chain of collisions in the dark that sank two and damaged several, killing 104 men. Seventeen were built.