HMAS Onslow
Encyclopedia
HMAS Onslow (SS 60/SSG 60) was one of six Oberon class submarines
Oberon class submarine
The Oberon class was a 27-boat class of British-built diesel-electric submarines based on the successful British Porpoise-class submarine....
operated by the Royal Australian Navy
Royal Australian Navy
The Royal Australian Navy is the naval branch of the Australian Defence Force. Following the Federation of Australia in 1901, the ships and resources of the separate colonial navies were integrated into a national force: the Commonwealth Naval Forces...
(RAN). The submarine was named after the town of Onslow, Western Australia
Onslow, Western Australia
Onslow is a coastal town in the Pilbara region of Western Australia, north of Perth. It currently has a population of around 573 people and is in the Shire of Ashburton Local Government Area....
and Sir Alexander Onslow
Alexander Onslow
Sir Alexander Campbell Onslow was the third Chief Justice of the Supreme Court of Western Australia, which is the highest ranking court in the Australian State of Western Australia....
, with the boat's motto and badge derived from Onslow's family heritage. Ordered in 1963, Onslow was laid down at the end of 1967 by Scotts Shipbuilding and Engineering Company
Scotts Shipbuilding and Engineering Company
Scotts Shipbuilding and Engineering Company Limited, often referred to simply as Scotts, was a Scottish shipbuilding company based in Greenock on the River Clyde.- History :...
in Scotland, launched almost a year later, and commissioned into the RAN at the end of 1968.
Although never involved in war, three major incidents occurred during Onslows career. The first occurred in 1972, when a disgruntled sailor who disobeyed orders caused the submarine to dive to almost twice her safe operating depth. As a result, the RAN changed the Submarine Service
Royal Australian Navy Submarine Service
The Royal Australian Navy Submarine Service is the collective name of the submarine element of the Royal Australian Navy. The service currently forms the Navy's Submarine Force Element Group and consists of six Collins class submarines....
from being able to 'conscript' any sailor for submarine service to volunteer only. The second happened in 1981, when carbon monoxide
Carbon monoxide
Carbon monoxide , also called carbonous oxide, is a colorless, odorless, and tasteless gas that is slightly lighter than air. It is highly toxic to humans and animals in higher quantities, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal...
fumes from one of the diesel generators filled the submarine, resulting in the death of one sailor. Although changes were made to submarine operating procedures, the boat's company was not provided with any psychological counseling, and the incident report remained classified until 2009. The third was a controversial line-crossing ceremony
Line-crossing ceremony
The ceremony of Crossing the Line is an initiation rite in the Royal Navy, U.S. Navy, U.S. Coast Guard, U.S. Marine Corps, and other navies that commemorates a sailor's first crossing of the Equator. Originally, the tradition was created as a test for seasoned sailors to ensure their new shipmates...
in 1995, which resulted in restrictions being placed on similar ceremonies aboard RAN vessels. During her career, Onslow became the first conventionally powered submarine to be fitted with anti ship missiles, and was successful in wargames: 'sinking' a seven ship flotila during Exercise Kangaroo 3 in 1980, and the United States supercarrier at RIMPAC 1998.
Onslow was decommissioned in 1999, and was presented to the Australian National Maritime Museum
Australian National Maritime Museum
The Australian National Maritime Museum is a federally-operated maritime museum located in Darling Harbour, Sydney. After consideration of the idea to establish a maritime museum, the Federal government announced that a national maritime museum would be constructed at Darling Harbour, tied into...
, where she is preserved as a museum ship.
Design and construction
Onslow was one of four Oberon class submarines ordered in 1963. The last of this group, Onslow was laid down by Scotts Shipbuilding & Engineering Co. in Greenock, Scotland on 4 December 1967. She was launched by Princess Alexandra, The Honourable Lady OgilvyPrincess Alexandra, The Honourable Lady Ogilvy
Princess Alexandra, The Honourable Lady Ogilvy is the youngest granddaughter of King George V of the United Kingdom and Mary of Teck. She is the widow of Sir Angus Ogilvy...
on 3 December 1968, and commissioned into the RAN on 22 December 1969. The boat was named after the coastal town of Onslow, Western Australia
Onslow, Western Australia
Onslow is a coastal town in the Pilbara region of Western Australia, north of Perth. It currently has a population of around 573 people and is in the Shire of Ashburton Local Government Area....
, which was in turn named after Sir Alexander Onslow
Alexander Onslow
Sir Alexander Campbell Onslow was the third Chief Justice of the Supreme Court of Western Australia, which is the highest ranking court in the Australian State of Western Australia....
, the third Chief Justice of Western Australia
Chief Justice of Western Australia
The Chief Justice of Western Australia is the senior judge of the Supreme Court of Western Australia and the highest ranking judicial officer in the Australian state of Western Australia. The Chief Justice is both the judicial head of the Supreme Court as well as the administrative head...
. Onslows motto, Festina Lente
Festina lente
Festina lente or σπεῦδε βραδέως is a classical adage and oxymoron meaning "make haste slowly" or "more haste, less speed"...
(Latin for "Hasten Slowly"), is shared with the Onslow family
Earl of Onslow
Earl of Onslow, of Onslow in the County of Shropshire, is a title in the Peerage of the United Kingdom. It was created in 1801 for George Onslow, 4th Baron Onslow. The Onslow family descends from Arthur Onslow, who represented Bramber, Sussex and Guildford in the House of Commons...
, and the ship's badge contains a judge's wig. Although this was the only use of the name by the RAN, two surface ships of the Royal Navy have previously been named .
Beam (nautical)
The beam of a ship is its width at the widest point. Generally speaking, the wider the beam of a ship , the more initial stability it has, at expense of reserve stability in the event of a capsize, where more energy is required to right the vessel from its inverted position...
of 26.5 feet (8.1 m), and a draught of 18 feet (5.5 m) when surfaced. At full load displacement, Onslow displaces 2,030 tons when surfaced, and 2,410 tons when submerged. The two propeller shafts are each driven by an English Electric motor providing 3,500 brake horsepower and 4,500 shaft horsepower; the electricity for these is generated by two Admiralty Standard Range supercharged V16 diesel generators. These could propel the submarine at up to 12 knots (6.5 m/s) on the surface, and up to 17 knots (9.3 m/s) when submerged. Onslow had a maximum range of 9000 nautical miles (16,668 km) at 12 knots (6.5 m/s), and a test depth of 200 metres (656.2 ft) below sea level. When launched, the boat had a company of 8 officers and 56 sailors, but by the time she decommissioned, the number of sailors had increased to 60. In addition, up to 16 trainees could be carried.
Unlike other submarines in her class, Onslow was fitted with a four-man diver access hatch, allowing for easier deployment and recovery of special forces divers.
Armament
The main armament of Onslow was the six 21 inches (53.3 cm) bow torpedo tubes, capable of firing torpedoes or releasing sea mines. The British Mark 8 torpedo was initially carried by the submarine; this was replaced by the wire-guided Mark 23. During a refit from 1982 to 1984, Oberon became the first conventionally-powered submarine in the world to be fitted with anti-ship missiles; specifically the UGM-84 Sub HarpoonBoeing Harpoon
The Harpoon is an all-weather, over-the-horizon, anti-ship missile system, developed and manufactured by McDonnell Douglas . In 2004, Boeing delivered the 7,000th Harpoon unit since the weapon's introduction in 1977...
. At the same time, the Mark 23 torpedoes were replaced by the United States Mark 48
Mark 48 torpedo
The Mark 48 and its improved ADCAP variant are heavyweight submarine-launched torpedoes. They were designed to sink fast, deep-diving nuclear-powered submarines and high-performance surface ships.-History:...
wire-guided torpedo. As of 1996, the standard payload of Onslow was a mix of 20 Mark 48 Mod 4 torpedoes and Sub Harpoon missiles. Some or all of the torpedo payload could be replaced by Mark 5 Stonefish
Stonefish (mine)
Named after a venomous fish, the Stonefish influence mine is manufactured by a British company . Originally, the weapon was supplied to the Royal Navy, but it has also been exported to friendly countries such as Australia, which has both warstock and training versions of Stonefish.Stonefish mines...
sea mines, which were deployed through the torpedo tubes.
The submarine's secondary armament consisted of two stern-mounted, short-length 21 inches (53.3 cm) torpedo tubes: these were intended for use against pursuing submarines, but the development of steerable wire-guided torpedoes shortly after the boat entered service made these redundant, and they were closed off during the 1982-84 refit. The aft tubes fired Mark 20 anti-submarine torpedoes.
1970–1981
Onslow arrived in Sydney at the conclusion of her delivery voyage to Australia on 4 July 1970. On board was Vice Admiral Sir Victor SmithVictor Smith
Admiral Sir Victor Alfred Trumper Smith AC, KBE, CB, DSC, RAN was a senior officer within the Royal Australian Navy, eventually becoming the first Australian to achieve the rank of admiral and serving as Chairman, Chiefs of Staff Committee; the professional head of the Australian Military.-Early...
, at the time the Chief of Naval Staff
Chief of Navy (Australia)
The Chief of Navy is the most senior appointment in the Royal Australian Navy, responsible to the Chief of the Defence Force and the Secretary of Defence...
, who had embarked at Brisbane. The boat visited Pearl Harbor later that year; arriving without being detected by the USN until she surfaced in the middle of the harbour. Onslow returned to Pearl Harbor in 1971 to participate in the RIMPAC
RIMPAC
RIMPAC, the Rim of the Pacific Exercise, is the world's largest international maritime exercise. Conducted biennially , it is hosted and administered by the United States Navy, with the United States Marine Corps, United States Coast Guard, and Hawaii National Guard forces under the leadership of...
multinational naval exercise. During the exercise, a practice torpedo fired by a United States Coast Guard Cutter
United States Coast Guard Cutter
Cutter is the term used by the United States Coast Guard for its commissioned vessels. A Cutter is or greater in length, has a permanently assigned crew, and has accommodations for the crew to live aboard...
failed to disengage as designed and hit the submarine—the only damage was a small dent near the stern.
In 1972, the first major incident of Onslows career occurred. The submarine was performing dive tests off the continental shelf outside Sydney Heads
Sydney Heads
Sydney Heads , is the entrance to Port Jackson in Sydney, New South Wales, Australia.North Head and Quarantine Head are to the north, South Head and Dunbar Head are to the south. Middle Head, Georges Head and Chowder Head are to the west and within the bay...
. One of the boat's company, transferred to the RAN Submarine Service
Royal Australian Navy Submarine Service
The Royal Australian Navy Submarine Service is the collective name of the submarine element of the Royal Australian Navy. The service currently forms the Navy's Submarine Force Element Group and consists of six Collins class submarines....
against his will, refused to obey an order to close the valve on forward ballast tank, causing it to overfill with seawater and forcing the submarine into a steep crash dive
Crash dive
A crash dive is a maneuver performed by a submarine to submerge as quickly as possible to avoid attack. Crash diving from the surface to avoid attack has been largely rendered obsolete with the advent of nuclear-powered submarines as they operate constantly submerged and are unlikely to be found on...
. The dive took Onslow to a depth of 366 metres (1,200.8 ft), well beyond the 200 metres (656.2 ft) safe operating depth of the Oberon class
Oberon class submarine
The Oberon class was a 27-boat class of British-built diesel-electric submarines based on the successful British Porpoise-class submarine....
, before another sailor was able to close the valve. Seven tons of water had been taken on by the ballast tank, and with not enough compressed air available to completely empty the tank and allow the submarine to rise, Onslows company had to rely on the submarine's twin propeller screws to help make it to the surface. The sailor responsible for the incident was beaten by his comrades and removed from the submarine in a straitjacket upon the boat's return to submarine base . This incident led the RAN to change submarine service to volunteers only.
Onslow became the first vessel of the RAN to be assigned to the ANZUK
ANZUK
ANZUK was a tripartite force formed by Australia, New Zealand and the United Kingdom to defend the Asian Pacific region after the United Kingdom withdrew forces from the east of Suez in the early seventies. The ANZUK force was formed in 1971 and disbanded in 1974....
force in Singapore on 22 July 1972. The boat returned to Australia on 18 December. On 5 May 1975, Onslow began a two-year refit at Cockatoo Island Dockyard, becoming the first Australian submarine to use the dockyard's new slave dock. This dock had been built specifically for refit work on Oberon class submarines, and was the main location of all Onslows refits until 1990. In 1977, Onslow was presented with the Gloucester Cup
Gloucester Cup
The Gloucester Cup is the common name for three awards of the Australian Defence Force. Formally referred to as the Duke of Gloucester Cup, the three awards are presented to the most efficient infantry battalion of the Australian Army, ship of the Royal Australian Navy , and squadron of the Royal...
, marking her as the most efficient warship in the RAN during the previous year—Onslow was the first submarine to receive the award.
In 1980, Onslow participated in Exercise Kangaroo 3 as an opposing submarine
Opposing force
An opposing force or enemy force is a military unit tasked with representing an enemy, usually for training purposes in war game scenarios...
. During the exercise, Onslow carried out successful simulated attacks on all seven surface ships involved in the exercise without being 'sunk' herself, including a simultaneous 'attack' on two United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
(USN) amphibious warfare vessels and a RAN replenishment ship while they were under escort by the other four warships. To indicate her success, the submarine flew a Jolly Roger from her communications mast upon her return to port, which was marked with the silhouettes of her seven targets: the s and , the , the , the , the , and the .
The second major incident of the boat's career happened on 1 March 1981, when Onslow was participating in wargames with a Royal New Zealand Navy
Royal New Zealand Navy
The Royal New Zealand Navy is the maritime arm of the New Zealand Defence Force...
frigate off the coast of Sydney. While operating at periscope depth, the submarine spotted an 'enemy' helicopter and ceased snorting (the process of taking in air to operate the boat's two diesel generators and expelling the produced exhaust through a snorkel
Submarine snorkel
A submarine snorkel is a device which allows a submarine to operate submerged while still taking in air from above the surface. Navy personnel often refer to it as the snort.-History:...
) in preparation to dive. Both generators were turned off, but upon diving, it was quickly discovered that the starboard diesels had failed to switch off or had restarted, and as the exhaust snorkel was sealed, the carbon monoxide
Carbon monoxide
Carbon monoxide , also called carbonous oxide, is a colorless, odorless, and tasteless gas that is slightly lighter than air. It is highly toxic to humans and animals in higher quantities, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal...
exhaust was filling the submarine. Onslow rapidly resurfaced, and the exhaust was pumped from the submarine. Able Seaman Christopher Passlow, who had been on the lower deck of the submarine at the time, died of asphyxiation and carbon monoxide poisoning, while another eighteen were rendered unconscious or were convulsing because of blood poisoning. Upon returning to base, doctors found that one-third of the 66 survivors had absorbed twice the lethal limit of carbon monoxide into their blood. The company was given a week's leave, with no further assistance from the RAN; psychological or otherwise. Two submariners were later awarded decorations for bravery.
The RAN Board of Inquiry into the incident concluded that the accident was caused by human error—the duty engineer failed to shut down both engines—but members of Onslows complement disagree with this, claiming the problem to be mechanical in origin. Changes were made to Submarine Service
Royal Australian Navy Submarine Service
The Royal Australian Navy Submarine Service is the collective name of the submarine element of the Royal Australian Navy. The service currently forms the Navy's Submarine Force Element Group and consists of six Collins class submarines....
operating procedures as a result of the Inquiry, but the investigation and subsequent report remained classified until 2009, when the information was acquired by the Sunday Night
Sunday Night (Australian TV program)
Sunday Night is an Australian news and current affairs program produced and broadcast by the Seven Network. The program airs on Sunday nights at 6:30 pm, and is presented by Seven News Sydney presenter Chris Bath.-Overview:...
newsmagazine
Newsmagazine
A news magazine is a typed, printed, and published piece of paper, magazine or a radio or television program, usually weekly, featuring articles or segments on current events...
program under the Freedom of Information Act
Freedom of Information Act 1982
The Freedom of Information Act 1982 is Australian Commonwealth Freedom of Information legislation which gives members of the public rights of access to official documents of the Government of the Commonwealth and of its agencies.-Outline of the Act:...
. When interviewed by Sunday Night in March 2009, the deputy Chief of Navy, Rear Admiral Davyd Thomas
Davyd Thomas
Rear Admiral Davyd Rhys Thomas AO, CSC, RAN is a senior officer in the Royal Australian Navy.-Service history:Davyd Rhys Thomas was born on 2 May 1956 in Newcastle, New South Wales, and joined the Royal Australian Navy College from that city in 1974...
(who had been Passlow's divisional officer prior to the incident) promised counseling for the survivors, and claimed that prior treatment of the Onslow submariners was due to a limited understanding of post-traumatic stress disorder
Post-traumatic stress disorder
Posttraumaticstress disorder is a severe anxiety disorder that can develop after exposure to any event that results in psychological trauma. This event may involve the threat of death to oneself or to someone else, or to one's own or someone else's physical, sexual, or psychological integrity,...
back in the 1980s.
1982–1990
Onslow underwent a modernisation refit from 1982 until 1984; becoming the third Australian Oberon to be modernised. As part of the modernisation, integrated data processing and fire control systems were installed, and the boat was fitted with Micropuffs passive ranging sonar. The torpedo payload was upgraded to the United States Mark 48 wire-guided torpedoMark 48 torpedo
The Mark 48 and its improved ADCAP variant are heavyweight submarine-launched torpedoes. They were designed to sink fast, deep-diving nuclear-powered submarines and high-performance surface ships.-History:...
. In addition to new torpedoes, the modernisation allowed Oberon class submarines to carry and fire the Harpoon anti-ship missile
Boeing Harpoon
The Harpoon is an all-weather, over-the-horizon, anti-ship missile system, developed and manufactured by McDonnell Douglas . In 2004, Boeing delivered the 7,000th Harpoon unit since the weapon's introduction in 1977...
through the torpedo tubes: Onslow became the first conventionally-powered submarine in the world to be fitted with guided anti-ship missiles.
Onslow was the first Australian submarine to visit the west coast of the United States of America when she arrived in San Diego on 17 July 1985. The boat made goodwill visits to the cities of San Francisco and Seattle during mid-August, before participating in the Royal Fleet Review for the 75th anniversary of the Royal Canadian Navy
Royal Canadian Navy
The history of the Royal Canadian Navy goes back to 1910, when the naval force was created as the Naval Service of Canada and renamed a year later by King George V. The Royal Canadian Navy is one of the three environmental commands of the Canadian Forces...
.
Onslows "safe to dive" certificate ran out just after Christmas 1989. The Australian government had been trialling a program whereby refit work was tendered out to the private sector; delays in selecting the winning company and allocating the funds meant that an 18-month refit of the submarine scheduled to begin at the start of 1990 did not commence on time. Australian Defence Industries
Australian Defence Industries
Thales Australia is a primary defence contractor for the Australian Defence Force. Thales Australia is best known for its naval ship repair operations, and currently leases the Captain Cook graving dock at Garden Island Naval Base in Sydney, New South Wales and also leases and occupies many of the...
(ADI) was awarded the $100 million refit contract for Onslow and sister submarine in July. Cockatoo Island's slave dock was transferred to the ADI facilities at Garden Island in November 1990, and was used for the refit. It was later found, during arbitration between the Australian Government and Cockatoo Island Dockyard for various issues, that by tendering out the submarine refits to other companies, the government was in breach of contract with the Dockyard; A$17.3 million in compensation was awarded to the dockyard in August 1996 for loss of profits and overhead costs.
1990–1999
In the early 1990s, four of Onslows sister boats were decommissioned from service. By 1996, Onslow and Otama were the only members of the class in active service.During 1995, Onslow was deployed to South East Asia. During this deployment, the personnel of Onslow were involved in a controversial line-crossing ceremony
Line-crossing ceremony
The ceremony of Crossing the Line is an initiation rite in the Royal Navy, U.S. Navy, U.S. Coast Guard, U.S. Marine Corps, and other navies that commemorates a sailor's first crossing of the Equator. Originally, the tradition was created as a test for seasoned sailors to ensure their new shipmates...
while operating near the equator. During this particular ceremony, normally intended to induct new sailors into the 'court of King Neptune', the victims were verbally and physically abused, had their pelvises and genitals covered in what was described as a "blistering concoction", then thrown overboard and forced to stay there until the rest of the company permitted them onboard. When one of the victimised sailors complained to superiors, he became subject to several administrative errors and inconveniences, to the point where he was forced to resign a year later. The sailor acquired a copy of a videotape made of the ceremony and presented it to the Nine Network
Nine Network
The Nine Network , is an Australian television network with headquarters based in Willoughby, a suburb located on the North Shore of Sydney. For 50 years since television's inception in Australia, between 1956 and 2006, it was the most watched television network in Australia...
, which broke the story on 6 July 1999. An inquiry into the incident aboard Onslow was held, which found that although guidelines had been developed in the years after the incident to prevent harassment in the Australian Defence Force, disciplinary charges against the sailors involved could not be laid, as more than three years had passed since the offence. The inquiry also stated that while line-crossing ceremonies would continue to be held aboard RAN vessels, they would be supervised by a non-involved member of the crew to prevent similar extreme situations developing. The deployment ended in December, with Onslow visiting her namesake town for the last time on her return to Australia.
On the evening of 16 April 1997, three Australian Special Air Service Regiment
Australian Special Air Service Regiment
The Special Air Service Regiment, officially abbreviated SASR but commonly known as the SAS, is a special forces unit of the Australian Army...
soldiers were injured when they were thrown from their Zodiac boat during launch and recovery exercises with the submarine. Later that year, in November, Onslow participated in a joint RAN-RAAF
Royal Australian Air Force
The Royal Australian Air Force is the air force branch of the Australian Defence Force. The RAAF was formed in March 1921. It continues the traditions of the Australian Flying Corps , which was formed on 22 October 1912. The RAAF has taken part in many of the 20th century's major conflicts...
exercise off the coast of Western Australia. Over the end of 1997 and the start of 1998, Onslow and Otama were used for trials of the Australian-designed Narama towed array sonar
Towed array sonar
A towed array sonar is a sonar array that is towed behind a submarine or surface ship. It is basically a long cable, up to 5 km, with hydrophones that is trailed behind the ship when deployed. The hydrophones are placed at specific distances along the cable...
. The Narama sonar was one of the towed arrays under consideration for incorporation with the under-development Collins class submarines
Collins class submarine
The Collins class is a class of six Australian-built diesel-electric submarines operated by the Royal Australian Navy . The Collins class takes its name from Australian Vice Admiral John Augustine Collins; all six submarines are named after significant RAN personnel who distinguished themselves in...
, and was the array selected.
In mid-1998, the date of Onslows decommissioning was announced for early 1999. Representatives from the town of Onslow, Western Australia
Onslow, Western Australia
Onslow is a coastal town in the Pilbara region of Western Australia, north of Perth. It currently has a population of around 573 people and is in the Shire of Ashburton Local Government Area....
requested that the submarine visit her namesake town before decommissioning, but were informed that the submarine's planned operational schedule could not accommodate such a visit. As part of this schedule, Onslow participated in the 1998 RIMPAC
RIMPAC
RIMPAC, the Rim of the Pacific Exercise, is the world's largest international maritime exercise. Conducted biennially , it is hosted and administered by the United States Navy, with the United States Marine Corps, United States Coast Guard, and Hawaii National Guard forces under the leadership of...
exercise. The submarine had to pull out of the early part of the exercise: a resistor in the motor room switchboard had begun to smoke, forcing Onslow to return to Pearl Harbor for repairs. She departed on 12 July, but was forced to return less than 24 hours later when a smouldering smell was noticed. The boat's luck changed during the latter part of RIMPAC 98, when on the morning of 10 August, Onslow located the 'enemy' Nimitz class
Nimitz class aircraft carrier
The Nimitz-class supercarriers are a class of ten nuclear-powered aircraft carriers in service with the United States Navy. With an overall length of and full-load displacements of over 100,000 long tons, they are the largest capital ships in the world...
supercarrier , closed to within 300 metres (984.3 ft) without being detected, then released green flares to indicate her location, 'sinking' the supercarrier. From 7 November onwards, Onslow was used as the target submarine for the annual Fincastle competition
Fincastle competition
The International Fincastle Competition is a contest of skills between the air forces of the United Kingdom, Australia, Canada and New Zealand. During the competition, crews compete in anti-submarine warfare, anti-surface warfare, and intelligence and surveillance gathering.-Origins:The Fincastle...
. Onslow operated on a secret patrol course 130 nautical miles (240.8 km) south of Kangaroo Island
Kangaroo Island
Kangaroo Island is Australia's third-largest island after Tasmania and Melville Island. It is southwest of Adelaide at the entrance of Gulf St Vincent. Its closest point to the mainland is off Cape Jervis, on the tip of the Fleurieu Peninsula in the state of South Australia. The island is long...
while aircraft from the competing Australian, British, Canadian, and New Zealand air forces attempted to locate and 'sink' her. No. 5 Squadron RNZAF
No. 5 Squadron RNZAF
No. 5 Squadron RNZAF is a squadron of the Royal New Zealand Air Force formed during November 1941 in Fiji. It remains on active duty and logged 2,300 hours flight time in 2007.-World War II:...
was declared the winner, although all teams were successful in locating the submarine during at least one of their three attempts.
Decommissioning and preservation
On 3 May 1999, the submarine was towed from Platypus to the Australian National Maritime Museum
Australian National Maritime Museum
The Australian National Maritime Museum is a federally-operated maritime museum located in Darling Harbour, Sydney. After consideration of the idea to establish a maritime museum, the Federal government announced that a national maritime museum would be constructed at Darling Harbour, tied into...
at Darling Harbour. Onslow was docked next to , another warship belonging to the museum, and was officially opened to the public on 1 June 1999. Onslow is the second RAN submarine to be preserved as a museum ship
Museum ship
A museum ship, or sometimes memorial ship, is a ship that has been preserved and converted into a museum open to the public, for educational or memorial purposes...
; the first was sister submarine , which was decommissioned at the end of 1998 and installed at the Western Australian Maritime Museum. As of 2004, she is one of seven Oberon class submarines preserved in this manner.
On 22 November 2002, Onslow was taken by tugs to Garden Island for three weeks of maintenance in drydock. This included cleaning and repainting of the hull, replacement of the tributyltin
Tributyltin
Tributyltin compounds are a group of compounds containing the 3Sn moiety, such as tributyltin hydride or tributyltin oxide. They are the main active ingredients in certain biocides used to control a broad spectrum of organisms...
coating used to prevent biofouling with a coating that was not harmful to marine organisms, and the sealing of several ballast tanks to improve the boat's stability and raise the aft section relative to the waterline. Onslow was returned to the museum on 11 December, and re-opened to the public three days later.
In October and November 2008, Onslow returned to Garden Island for maintenance and upkeep. During this refit, an additional torpedo was loaded into the submarine's torpedo tubes and her hull was cleaned and painted.
External links
- RAN Virtual Fleet – Includes virtual tour inside HMAS Onslow.
- Australian National Maritime Museum – Submarine Entries from the Australian National Maritime Museum's weblog relating to Onslows 2008 maintenance period.