The four missing military personnel who are presumed dead after a helicopter crash off the Queensland coast are being remembered by their colleagues, family, friends and government for their service.
Defence minister Richard Marles said "significant wreckage" of the MRH-90 Taipan aircraft has been discovered after the helicopter went down near Lindeman Island, which is near Hamilton Island, at about 11pm on Friday during the Talisman Sabre military exercises
Those onboard and missing were identified yesterday as Captain Daniel Lyon, Lieutenant Maxwell Nugent, Corporal Alexander Naggs, and Warrant Officer Joseph Laycock.
"With every passing hour, it is now clear any hope of finding Captain Lyon, Lieutenant Nugent, Corporal Naggs and Warrant Office Laycock alive has been lost," Marles said.
"The tragedies that have taken place in the Whitsundays have transferred from those being of search and rescue to an activity of recovery."
Marles said there will be a full and thorough investigation into the crash but for now, the government and defence force stands with the families of the men.
"They will spend the rest of our lives with an unfavourable hole," Marles said.
"To them, we are so deeply sorry and so grateful.
"They have every right to feel an intense sense of pride.
"Amidst the inadequacy of these words that, I wanted to know they stand in the warm embrace of the entire nation."
Marles said defence exercises are serious and carry a "dangerous" risk but play a "critical part in providing for the collective security and peace of the region in which we live".
Marles said the helicopters were certified to fly but in the meantime have been grounded while the investigation is underway.
"In the meantime, our fleet of MRH-90s have been grounded and they will not fly again until we understand what has happened and we have modified or acted accordingly," he said.
Chief of the Defence Force General Angus Campbell said the return of the Taipans will form part of the aviation investigation.
"There is going to be an investigation is there always would be, and it will be utterly thorough, and consider all factors, but we must not speculate and we must not in any way influence or distort the presumptions of that investigation," he said.
Tributes to remember the four military personnel killed
Queensland MP Phillip Thompson, who served with Corporal Naggs in the First Battalion Royal Australian Regiment, said his thoughts, prayers and heart go out to his family.
"He was a happy guy, a great person, he was someone who was never too hard for anything," he said.
"A life of service. He was someone if you asked a question you'd get an answer.
"He's one of the nicest blokes I've ever met."
In the flux of tributes by government and ADF officials, Governor-General David Hurley extended his sympathy to the loved ones and colleagues of the four men.
"As they stepped forward to serve us, so must we to honour their memory, remember their sacrifice and support their families," he said.
"It is a tragedy, and Linda and my thoughts are with the families, friends and other defence force personnel at this difficult time. I hope that the knowledge of our nation's gratitude is of some comfort in this moment of intense grief."
Former ADF-member-turned-politician Jacqui Lambie said her heart goes out to the families of the four men.
"To the defence community out there, I just want you to know that you have the country behind you," she said.
"We are thinking of you."
Search for bodies underway as MRH-90s reviewed
The search for the MRH-90 and the four aviators from the 6th aviation regiment based at the Holsworthy army barracks in Sydney is now a recovery effort.
An exclusion zone of more than 100 square kilometres is in place off the coast.
Campbell said authorities will do everything possible to bring the men's bodies home to their families.
The crash marks one of Australia's worst peacetime military disasters in almost 20 years, and came as the aircraft was being phased out of military use.
The decision to discontinue their use was made after one went down off the coast of New South Wales near Jervis Bay in March. Ten people were on-board, but all managed to make their way out.
The fleet was also grounded then but returned to the skies in April with "risk mitigations" in place, a Defence spokesperson said at the time.
Marles said the MRH-90s were due to come out of service at the end of next year in favour of Blackhawk aircraft.
"We will move through the process of putting the Blackhawks into service as quickly as we can, but as thoroughly as we need to, and we will not be finding MRH-90s until we understand what has happened," he said.
The staggering sums countries spend on defending themselves
Prime Minister Anthony Albanese said earlier it was a reminder that there were no "safe and easy days" for people in the military.
Albanese offered his condolences to the families of the victims, who he said were trying to "build a more peaceful and safe world" during the failed operation.
"On behalf of our nation, our thoughts and prayers are with the families, friends and colleagues of those who are missing," he said.
"Our thoughts are also with those that they serve alongside - friends, brothers and sisters in uniform who even now are aiding in the search effort. I'd also like to thank the support from other nations during this search effort".
"Our thoughts are also with those that they serve alongside - friends, brothers and sisters in uniform who even now are aiding in the search effort. I'd also like to thank the support from other nations during this search effort".
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