HMAS Australia (1911) - Decommissioning and Fate

Decommissioning and Fate

Australia returned to Sydney in November 1921, and was paid off into reserve in December. By this time battlecruisers built before the Battle of Jutland were considered obsolete, and there is no record of the Admiralty suggesting that Australia purchase a replacement. Moreover, it is unlikely that the Australian Government would have agreed to such a suggestion given the prevailing political and financial conditions. As the Admiralty had decided to phase out 12-inch guns and had stopped the manufacture of shells for these weapons shortly after the war, it would have been necessary to replace Australia's main armament once the Navy's stock of shells reached their expiry date given that it was not possible to produce replacement shells in Australia. This was also not financially feasible for the government, particularly given the RAN's lack of interest in retaining the ship.

The 1922 Washington Naval Treaty was a mutual naval arms limitation and disarmament treaty between the five major naval powers of the time: the United Kingdom, the United States of America, Japan, Italy, and France. One of the main aspects of the treaty was the limitation on the number and size of capital ships each nation possessed; as the RAN was counted as part of the Royal Navy for the purposes of the treaty, Australia was one of the battlecruisers nominated for disposal to meet the British limit. The battlecruiser had to be made unusable for warlike activities within six months of the treaty's ratification, then disposed of by scuttling, as Australia did not have the facilities to break her up for scrap, and the British share of target ships was taken up by Royal Navy vessels. This was the only time the Australian military has been affected by a disarmament treaty until the 1997 Ottawa Treaty banning the use of anti-personnel mines.

Some equipment had been removed when Australia was decommissioned for use in other ships, but after the November 1923 decision by the Cabinet confirming the scuttling, RAN personnel and private contractors began to remove piping and other small fittings. Between November 1923 and January 1924, £68,000 of equipment was reclaimed; over half was donated to tertiary education centres (some of which was still in use in the 1970s), while the rest was either marked for use in future warships, or sold as souvenirs. Some consideration was given to reusing Australia's 12-inch guns in coastal fortifications, but this did not occur as ammunition for these weapons was no longer being manufactured by the British, and the cost of building suitable structures was excessive. It was instead decided to sink the gun turrets and spare barrels with the rest of the ship. There was also a proposal to remove Australia's conning tower and install it on the Sydney Harbour foreshore; although this did not go ahead, the idea was later used when the foremast of HMAS Sydney was erected as a monument at Bradleys Head. The ship's outer starboard propeller is on display at the Australian War Memorial, while other artefacts are in the collections of the War Memorial, the Australian National Maritime Museum, and the Royal Australian Navy Heritage Centre.

The scuttling was originally scheduled for Anzac Day (25 April) 1924, but was brought forward to 12 April, so the visiting British Special Service Squadron could participate. On the day of the sinking, Australia was towed out to a point 25 nautical miles (46 km; 29 mi) north east of Sydney Heads. Under the terms of the Washington Treaty, the battlecruiser needed to be sunk in water that was deep enough to make it infeasible to refloat her at a future date. The former flagship was escorted by the Australian warships Melbourne, Brisbane, Adelaide, Anzac, and Stalwart, the ships of the Special Service Squadron, and several civilian ferries carrying passengers. Many personnel volunteered to be part of the scuttling party, but only those who had served aboard her were selected. At 14:30, the scuttling party set the charges, opened all seacocks, and cleared the ship. Explosive charges blew a hole in the hull a few minutes later, but it took 20 minutes for the intake of water to bring holes cut in the battlecruiser's upper flanks to the waterline. The angle of list increased significantly, causing the three spare 12-inch barrels lashed to the deck to break free and roll overboard, before Australia inverted completely and began to sink stern-first. Australia submerged completely at 14:51; a Royal Australian Air Force aircraft dropped a wreath where the warship had sunk, while Brisbane fired a rolling 21-gun salute. The wreck was gazetted as being at 33°53′25″S 151°46′5″E / 33.89028°S 151.76806°E / -33.89028; 151.76806, 270 metres (890 ft) below. However, there were discrepancies with other sources, and the exact location of Australia was unknown.

There are two schools of thought surrounding the decision to scuttle the battlecruiser. The first is that sinking Australia was a major blow to the nation's ability to defend herself. Following the battlecruiser's scuttling, the most powerful warships in the RAN were four old light cruisers. The battlecruiser had served as a deterrent to German naval action against Australia during the war, and with growing tensions between Japan and the United States of America, that deterrence may have been required if the Japanese and Americans became aggressive towards each other or towards Australia. The opposing argument is that, while an emotive and symbolic loss, the ship was obsolete, and would have been a drain on resources. Operating and maintaining the warship was beyond the capabilities of the RAN's post-war budgets, necessitating the ship's reduction in status in 1920 and assignment to reserve in 1921. Ammunition and replacement barrels for the main guns were no longer manufactured. To remain effective, Australia required major modernisation (including new propulsion machinery, increased armour and armament, and new fire control systems) at a cost equivalent to a new County class cruiser.

In 1990, a large, unknown shipwreck was encountered by the Furgo Seafloor Surveys vessel MV Moana Wave 1 while surveying the path of the Pacific Rim West Submarine Telecommunications Cable. One of the survey ship's crew theorised that the wreck, located at 33°51′54.21″S 155°44′25.11″E / 33.8650583°S 155.7403083°E / -33.8650583; 155.7403083 in 390 metres (1,280 ft) of water, was Australia, but Furgo kept the information to themselves until 2002, when the company's Australian mentioned the discovery during a conference. This piqued the interest of a member of the New South Wales Heritage Office (now the Heritage Branch of the New South Wales Office of Environment and Heritage) requested copy's of the company's data. The size and location of the ship pointed towards it being Australia, but the depth meant verification through inspection could only be achieved with a remote operated vehicle (ROV). The RAN was approached in 2007 for assistance, but although they supported the project, the RAN did not have the equipment to assist. In March 2007, the United States Navy loaned the deep-sea ROV CURV-21 to the Australian Government, to locate and recover a Black Hawk helicopter which crashed during the Australian response to the 2006 Fijian coup d'état. While en-route back to Australia, the ROV, carried aboard Defence Maritime Services vessel Seahorse Standard, was directed to Furgo's coordinates at the request of the NSW Heritage Office to verify and inspect the wreck. Video footage captured by the ROV allowed the NSW Heritage Office to confirm that the wreck was Australia by matching features like the superstructure and masts to historical photographs. Although initially sinking stern-first, the battlecruiser levelled out as she sank, with the aft mast the first to strike the bottom. After hitting the seabed, Australia slid about 400 metres (1,300 ft) to her final resting place. The wreck site is protected under the federal Historic Shipwrecks Act 1976.