The two ships were attacked by Japanese aircraft along the way, and were subsequently late in arriving at their destination, missing a planned rendezvous with HMAS Kuru.

During a subsequent confrontation with thirteen Japanese aircraft on 1 December, Armidale was struck by two torpedoes and a bomb, and began to sink; the order to abandon ship was given.

Many of the survivors credited their lives to Sheean and he was posthumously mentioned in despatches, this award was later cancelled on 1 December 2020 when upgraded to the Victoria Cross for Australia.

[6][7] On finishing his initial training course, Sheean was attached to the Flinders Naval Depot in Western Port, Victoria, for further instruction from 11 February 1942.

Returning to Sydney eleven days after the raid, Sheean joined the newly commissioned Bathurst-class corvette HMAS Armidale as an Oerlikon anti-aircraft gun loader.

[2][4] Leaving Sydney Harbour in late August 1942, Sheean served aboard Armidale as she carried out "relatively uneventful" escort duties along the North Queensland, Port Moresby and Milne Bay coasts over the subsequent two months.

[6][8] On 24 November 1942, the evacuation of the 2/2nd Australian Independent Company from Timor along with 150 Portuguese people was approved by the Allied Land Forces Headquarters.

In response to this, Commodore Cuthbert Pope, the Naval Officer-in-Charge Darwin, organised an operation utilising HMA Ships Kuru, Castlemaine and Armidale.

[2][9] Continuing in their voyage, Armidale and Castlemaine were attacked twice more by air, each time by a formation of bombers that bombed and machine-gunned the ships.

Having made sure that Kuru was not in the bay, the two corvettes decided to abandon the mission and sailed south in order to return to Darwin.

While approximately 110 kilometres (59 nmi) south of Betano, Armidale and Castlemaine sighted Kuru, and the three ships closed by dawn.

Assessing the situation, Sullivan—as senior officer—decided that Armidale would accompany Kuru in order to unload the former's passengers at Betano while Castlemaine returned to Darwin.

However, at 15:15, the vessel was struck by two air-launched torpedoes, one hitting her port side and the other colliding with the engineering spaces, before a bomb exploded aft.

Scrambling across the deck, he strapped himself into the aft Oerlikon 20 mm cannon and began shooting at the fighters in an effort to protect some of the sailors already in the sea.

[4] Sheean was among 100 of the original 149 people on board HMAS Armidale at the time of the attack who were killed during the ship's sinking and its aftermath.

[21] The Bill came as part of a campaign by the then-leader of the Australian Labor Party and Federal Opposition, Kim Beazley, to secure more rights for war veterans.

Known as the 'Valour Inquiry', the Tribunal was directed to determine if the individuals were unduly overlooked for recognition at the time of their actions and, if so, whether late awards were appropriate.

[25] Mark Sullivan, the head of the Defence Honours and Awards Appeals Tribunal subsequently wrote to Reynolds to complain that she had misrepresented the panel's findings and misled the Senate.

In response to Sullivan's letter, Tasmanian Veterans Affairs Minister Guy Barnett and federal Senator Jacqui Lambie called for the decision to not award the medal to be reconsidered.

[27] The Chief of the Defence Force General Angus Campbell strongly advised the government to not award Sheean the medal.

[29] On 10 August 2020, Morrison accepted the findings of the panel and recommended the Queen posthumously award Sheean the Victoria Cross for Australia.