One of six Oberon-class submarines acquired by the Royal Australian Navy (RAN), HMAS Onslow was built by Scotts Shipbuilding and Engineering Company in Greenock, Scotland. Laid down on 4 December 1967 and launched on 3 December 1968, Onslow was commissioned into the RAN on 22 December 1969. She was named after the town of Onslow in Western Australia, and arrived at Sydney's Garden Island naval base on 4 July 1970, following her delivery voyage from Scotland. On 22 July 1972, Onslow was the first RAN vessel to be assigned to the ANZUK force of Australian, New Zealand, and UK naval vessels formed to provide maritime security in Asia-Pacific waters following the UK's withdrawal of permanent forces east of Suez; a second deployment with the ANZUK force followed in 1974. Further training and submarine warfare exercises were carried out by Onslow in following years, including participation in Exercise Kangaroo 3 in 1980, in which the submarine scored simulated hits on all seven surface ships involved in the exercise.
Between 1982 and 1984, HMAS Onslow was upgraded, including being fitted with anti-ship missiles (UG-84 Sub Harpoon), the first conventionally-powered submarine in the world to be so fitted. She also received new integrated data processing and fire control systems, and adopted new US-designed Mk 48 wire-guided torpedoes.
Of note, Onslow's career was marred by a handful of unfortunate incidents. In 1972, a disgruntled member of her crew disobeyed orders to close a ballast tank valve, causing the boat to sink to a depth of 366 metres (1,201 feet), or 166 metres below her safe operating depth. Using a combination of compressed air and her propellers, Onslow was able to surface, whereupon the crewman responsible for the near-disastrous dive was placed in a straitjacket and removed from the submarine. On 1 March 1981, carbon monoxide fumes from an onboard diesel generator filled Onslow's interior, causing one sailor's death and 18 injuries. The surviving crew were not given psychological counselling and the incident and subsequent inquiry report were classified until 2009. And in 1995, a rowdy crossing-the-line ceremony involving physical abuse and harassment aboard Onslow led to the imposition of restriction on future such ceremonies on all RAN ships and submarines.
While the Australian government decommissioned four of its six Oberon-class submarines by the mid-1990s, Onslow and her sister Otama, remained in service. Onslow participated in the 1998 serial of the Rim of the Pacific (RIMPAC) exercise in the waters off Hawaii, approaching undetected within 300 metres (980 feet) of the Nimitz-class carrier USS Carl Vinson and scoring a simulated 'kill'. Finally, on 30 March 1999, HMAS Onslow was decommissioned and, in April, donated to the Australian National Maritime Museum for preservation and display as a museum vessel. She opened to the public on 1 June 1999.
Photos taken 27 October 2014
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| HMAS Onslow, seen berthed next to the retired Australian destroyer HMAS Vampire at the Australian National Maritime Museum, Sydney. |
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| The Onslow's bulbous bow houses the submarine's Atlas Elektronik Type CSU3-41 sonar array. Note the forward diving planes are folded up. |
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| The torpedo compartment aboard Onslow contains six tubes and space for 20 torpedoes, six stored in the tubes and an additional 14 in cradles in the compartment. Originally, she carried the British Mk 8 torpedo, subsequently replaced by the wire-guided Mk 23 torpedo. During a 1982-84 refit, Onslow was modified to take the 21-inch diameter American Mk 48 Mod 4 wire-guided torpedo. During this same refit, the torpedo tubes were also certified to fire the UGM-84 Sub-Harpoon missile, and Onslow became the world's first conventionally-powered submarine to carry this weapon. |
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| Aft of the torpedo room is one of the compartments used for accommodating a number of crewmen. Each sailor had his own bunk so the practice of 'hot bunking' was not required. |
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| Looking forward up the main passageway aboard HMAS Onslow, with bunks along the port side and various offices on the starboard side. |
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| The officers' wardroom provides a place for the Onslow's eight officers to relax and take their meals. |
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| The fire control consoles in the control compartment. |
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| The navigator's chart table on the starboard side of the control compartment. |
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| The captain's cabin, cramped by surface ship standards but offering the most privacy of any accommodation space aboard Onslow. |
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| One of the two Admiralty Standard supercharged V16 diesel generators which power two English Electric motors, providing 4,500 shaft horsepower and propelling Onslow at 12 knots when surfaced and 17 knots when submerged. |
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| The propeller motor control panel, located in the aft section. Onslow's diesel-electric engines gave the boat a range of 9,000 nautical miles at 12 knots. |
HMAS Onslow - Specifications
Displacement: 2,030 tons (surfaced) / 2,410 tons submerged
Length: 90 metres (295.2 feet)
Beam: 8.1 metres (26.5 feet)
Draught: 5.5 metres (18 feet)
Propulsion: Two Admiralty Standard Range supercharged V16 diesel generators and two English Electric motors, generating 4,500 shaft horsepower on two shafts
Speed: 12 knots (22 km/h) surfaced; 17 knots (31 km/h) submerged; 11 knots (20 km/h) at snorkel depth
Range: 17,000 km (9,000 nautical miles) at 12 knots
Test Depth: 200 metres (660 feet)
Armament: Mix of Mk 48 Mod 4 torpedoes and UGM-84 Sub Harpoon missiles, launched from 6 x 21-inch bow tubes and 2 x short-length 21-inch stern tubes (later removed); tubes also capable of launching Mk 5 Stonefish sea mines
Complement: 8 officers, 60 sailors (at decommissioning)