This submarine was the first loss in WW1. HMAS AE1 was an Australian E Class submarine with Royal Navy Officers and a mixed crew of Royal Navy and Royal Australian Navy Ratings. AE1 was the first of Two E Class Submarines ordered for the Royal Australian Navy and built in the Vickers Shipyard at Barrow in Furness.

After a Commissioning Ceremony at Portsmouth, HMAS AE1 made the passage to Australia‚ leaving Portsmouth on 2 March 1914 and arriving in Sydney on 23 May 1914. After refitting at Sydney Submarine AE1 joined the Australian Forces at the Bismarck Archipelago but disappeared without trace (and with the loss of all Officers and Ratings) off the Island of New Britain in the Pacific on 14 September 1914.

AE1 was patrolling in the St George Straits off New Britain on 14 September 1914 when she vanished and was lost with all hands. The location of the submarine wreck remained unknown for over 100 years although there had been many searches.

On 20 December 2017 a side scan sonar search conducted from MV FUGRO EQUATOR finally located the wreck at a depth of some 300 metres in the St George Channel. Analysis of sonar results and a photographic survey indicated that the most likely reason for the loss of AE1 and her crew was a diving accident and not the result of any enemy hostile action.

The crew of AE1 was larger than the standard crew for an E Class Submarine. It included extra personnel from the Spare Crew allocated by Thomas Besant (as Senior Submarine Officer) to allow the Engine Room to work in four watches with the Chief ERA and the Chief Stoker out of the Watch Bill to supervise/monitor the running of the machinery.