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Further Reading

HMS Porpoise

After World War II there was a strange paralysis in naval construction as all countries attempted to come to terms with a nuclear world. By the second half of the 1950s it was clear that Britain would 'go nuclear' in terms of submarines in both propulsion and as weapons platforms. But created a 'strategic gap' which the Flag Officer Submarines was anxious to bridge with an improved diesel-electric conventional submarine which could be adapted as a strike platform. The nuclear submarine offered 'the only means of making a significant contribution to the Nuclear Deterrent, which can be adequately supported by the country's economy'. But a nuclear capability did not spell the end of a conventional capability.

Indeed, between the mid 1950s and the early 1960s eight Porpoise Class submarines were built. With four yards in this market, however, it could hardly be described as clear. By May 1961, Admiralty policy in respect of the balance between conventional and nuclear submarines had significantly altered. Whereas the previous policy was to build two conventional submarines per year until at least 1968-69 the new policy was to stop building conventional submarines altogether after two more had been ordered later in the year.

The Porpoise and Oberon Class diesel boats were considered the best conventional submarines ever at the time. A total of 8 Porpoise Class submarines were built. The Porpoise Class, built between 1954 - 61, was the first attack submarine design used by the Royal Navy after the Second World War. Although there were some technical and interior differences, from the outside both these classes looked almost identical. These Overseas Patrol Submarines, later known as Attack Submarines, were capable of great distances and could run almost silently. They were updated with the latest sonar equipment during the 1980s - this new technology easily spotted on their bows.

The Porpoise class submarines were the first major class of submarine to be built by the United Kingdom after the Second World War for the Royal Navy. The first Porpoise class was HMS CACHALOT which was laid down in 1955 at Scott's Shipyards. These boats were substantially remodelled in structure from the A and T classes of submarine. This class and some later A class, incorporated the 'Snort' underwater breathing system. The Oberon class submarine was derived from the Porpoise class submarine design. The Porpoise and Oberon classes were probably the most efficient conventional powered submarines in the world at the time. They were noted for their near-silent running and their maximum diving depth of 300 meters.

In the early 1960s Australia purchased six Oberon class submarines the first being H.M.A.S OXLEY which was laid down on 29 June 1965 at Scott's, Greenock and the others being laid down up until 1973 when construction began on the last, H.M.A.S. OTAMA on 28 March 1973. By the year 1982 it was realised that the Oberon class submarines were approaching an age where they had to be replaced. In June of 1987 a contract was signed for the purchase of six new submarines to be built as a joint venture between the Australian Submarine Corporation and Kockhams, a Swedish company who had designed a submarine for Australian use, thereafter called the Collins class.

They served the British Navy for well over a third of a century, the last of these submarines was decomissioned in 1993.