Two defence force personnel have sustained minor injuries after an army helicopter ditched into the water during routine counterterrorism training near Jervis Bay on the NSW south coast.
All 10 personnel on board the Australian Army MRH-90 Taipan multi-role helicopter were recovered from the water on Wednesday night and assessed at the HMAS Creswell naval academy, the Department of Defence said.
The Chief of Army Lieutenant General Simon Stuart said the incident had the potential to end in "tragedy".
"Quick responses from ADF personnel and emergency services and well-drilled teams prevented a potential tragedy," Chief Stuart said.
"We will conduct a thorough investigation into this incident to determine the cause and ensure the platform remains safe to operate."
Defence Minister Richard Marles said the two injuries involved one person hitting their head and another taking on sea water.
"They're being looked after and essentially people have been able to get out of this without any serious injury," he said.
"That represents an incredible achievement on the part of the crew — this was a textbook response to a loss of power.
"So we should be thankful for the professionalism of the men and women of our Defence Force. In this instance, they responded to a pretty terrifying situation and in the midst of a crisis managed to act in a way which has kept everyone alive."
Witnesses reportedly heard a "big flash, a big bang, and a bit of fire on top of the chopper" before the helicopter ditched.
Shoalhaven resident Col Evans, who was camping at a popular nearby campsite Green Patch, said he watched the military carrying out exercises in the area last night.
"We were sitting around the campfire, and we actually saw choppers coming overhead and half a dozen guys dangling from ropes from the chopper obviously carrying out an exercise," he said.
"They were only about treetop height, so they were really, really close."
Mr Evans said his wife discovered the downed helicopter early this morning.
"My wife came down to the beach to walk around 7am and said, 'Come on down to the beach. This thing has been beached.'"
The incident site was being contained by the Australian Federal Police and port services personnel.
The training activity has been temporarily paused as a precaution and the MRH-90 Taipan fleet will be grounded while the cause of the incident is investigated, defence said in a statement.
"At this time defence's priority is supporting the ADF members involved in the incident and their families," the department said.
An ACT police spokeswoman said they were assisting the defence-led response to the incident in a support role after receiving a call at 9:10pm.
NSW Ambulance also responded to the incident.
The MRH-90 Taipan has been plagued with issues since the Howard government ordered 46 of the European-designed helicopters in the mid-2000s.
Earlier this year, the federal government announced that the Taipans would be phased out in 2024 — 13 years ahead of the intended end of the project.
Defence grounded some or all of the fleet in 2019, 2020 and 2021 due to safety and maintenance concerns.
Story By: ABC Illawarra / By Claudia Williams, Matt Bevan, and Tim Fernandez
Stay tuned for the latest news on our radio stations