Submarines with diesel-electric power units had an important role to play in anti-submarine warfare and against surface ships. Their underwater endurance was not as great as that of nuclear submarines, but they were fast, silent and difficult to detect. The Royal Navy Patrol Submarine Fleet from 1955 onwards consisted of the Porpoise and Oberon Classes.
PORPOISE CLASS 1955
Designed in the early 1950s as replacements for the A boats, the Porpoise Class were the first post-war-built operational submarines to be accepted into service. As with the earlier minelayer submarines of the same class name, ordered in the 1930 Admiralty Programme, whether by accident or design, the first-of-class Porpoise, Narwhal and Rorqual were also built at Barrow. Of the other five submarines of the class, Finwhale, Grampus and Sealion were built at Cammell Lairds and Cachalot and Walrus at Scotts'.
