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SYDNEY - One of Australia's most intriguing wartime mysteries may have been solved after the Navy found what it believes to be the remains of a submarine which went missing in New Guinea more than 80 years ago.
The submarine, codenamed AE1, vanished in September 1914 with the loss of all 35 crew while patrolling near Rabaul on the island of New Britain, in what was then German New Guinea.
Commanded by British officers and with an Australian and British crew, it was in the area to support Allied operations against a strategically important German radio base in Rabaul.
Its disappearance marked Australia's first major loss of life in World War I.
Two Royal Australian Navy survey ships have been hunting for the wreck along the coast of New Britain and yesterday it looked as though one of them, HMAS Benalla, had found it.
The Veterans Affairs Minister, Bruce Billson, said he was cautiously optimistic that a 25 to 30m-long object detected on the sea floor near the Duke of York Islands was the wreckage of AE1.
Its exact location is being kept a secret for fear of interference by bounty hunters or divers.
"Locating the AE1 would help solve one of our country's most enduring naval mysteries. It would also provide some closure to the descendants of the 35 crew members who tragically lost their lives while serving our nation," Billson said.
The Navy plans to deploy a mine-hunting vessel equipped with a remotely operated submersible in the area to determine whether the object is in fact a wreck.
Mystery surrounds the fate of the AE1. A search in 1914 found no trace of the vessel and intelligence about the position of the German Navy at the time suggested it was unlikely the sub was attacked.
It may instead have sunk after running aground or colliding with a submerged object.
The AE1 and its sister ship, the AE2, were bought from Britain and arrived in Australia in May 1914.
In August 1914, five days after the British Empire declared war on Germany, the AE1 was dispatched to support operations against German forces on New Britain.
"She was last seen at 3.30pm on September 14, 1914, and was expected to return to Rabaul to rejoin the rest of the fleet," said Navy spokesman Captain Greg Sammut.
"Unfortunately she was not seen again. We believe it was unlikely she was lost to enemy action."
The AE2 was also lost during World War I. It sank in April 1915 in Turkey's Sea of Marmara after penetrating the Dardanelles during the Gallipoli campaign. Unlike the AE1, the AE2's crew all survived.
The wreck of the AE2 was found by Australian submarine hunters in 1998.
The search by HMAS Benalla and its sister ship, HMAS Shepparton, was aided by the work of retired Navy commander John Foster, who has investigated the fate of the AE1 for 30 years.