1959 - 1998: Oberon Class
Between 1959 and 1964, thirteen Oberon Class submarines were constructed for the Royal Navy, three of which Olympus, Orpheus and Osiris were built at Barrow. Although they have the same dimensions, displacement and machinery as the Porpoise Class, the Oberons incorporated some important developments, such as improved detection equipment and the ability to fire homing torpedoes.
Perhaps the most radical change that occurred with the introduction of the Oberon Class was the fact that for the first time in British submarines plastic was used in the superstructure construction - before and abaft the bridge, in most units the superstructure was mainly glass fibre laminate. In addition, the superstructure of the second ship, the Vickers-built Orpheus, was of aluminium.
Having acquired an enviable reputation for reliability and quietness, many Oberons have been sold to foreign buyers since 1962, and they are regarded as the best conventional submarines available.