In 1923 there was vigorous debate on the subject of whether Britain should build replacement submarines for the "J" Class or build them in Australia. Britain was chosen.

So the third attempt to establish Australia's submarine force began in April and June 1927 when HMAS Oxley and HMAS Otway were commissioned into the Royal Australian Navy.

On their delivery voyage which began in February 1928, cracks were found in their engine columns and both were laid up in Malta for over eight months. They both arrived in Australia in February 1929, just over a year after sailing from England.Unfortunately, Australia's third attempt at maintaining a submarine service was terminated when armament limitations and the deepening economic depression forced the paying off of both boats at the end of 1929. Both boats were transferred to the Royal Navy in 1931.

On 9 September 1939 the now HMS Oxley was the first allied naval casualty of World War II when she was sunk by a torpedo from another British submarine, HMS Triton. The apparent cause of this was an incorrect response to a recognition challenge. Apart from a small Dutch submarine (K9) used for training purposes during WWII, Australia would not operate submarines for the next thirty six years.

A liability rather than an asset, the K9 was used by the R.A.N. for less than a year in an anti-submarine training role. Commissioned into the navy in June 1943, she was manned by Royal navy personnel with some Australian volunteers. Her liability became obvious in that her batteries had a habit of exploding when she was dived, which was very disconcerting to the crew. She was paid off after nine months and passed back to Dutch control in 1944.

Although Australia had been short of submarines in WWII, Australian submariners were not as many British boats were commanded or crewed by Australian sailors. During the years 1949 - 1969 a total of ten "A" and "T" class were stationed in Sydney. Although never commissioned into the R.A.N., the running costs were met by Australia and New Zealand. They rendered valuable service to the R.A.N. and from this class were developed the later Oberon Class.

On the fifth attempt at establishing and Australian submarine arm the decision was taken to acquire a new force of four Oberon Class submarines to be built at Scotts on the Clyde. The first of this new breed was HMAS Oxley, commissioned in March 1967, followed by her sisters HMAS Otway, HMAS Ovens and HMAS Onslow. HMAS Oxley's arrival in Sydney coincided with the commissioning of the submarine base HMAS Platypus established at Neutral bay, Sydney. In 1977-78 two more units, HMAS Orion and HMAS Otama, joined the squadron and all were eventually modernized in an ambitious and successful program.

Now these aging boats which have given excellent service to the R.A.N. are currently being phased out to make way for the new breed of Submarine being built in South Australia, the Collins Class. From a beginning which relied heavily on support from mother England, the Australian submarine service has matured into an elite branch of the navy with a company whose pride of service is unsurpassed.