Black box of MRH

The black box of a crashed Australian Army helicopter has been found a week and a half after it ditched into the sea with four crew onboard in Queensland's Whitsundays.

The MRH90 Taipan crashed into the ocean south of Hamilton Island during a night-time training exercise on July 28.

Captain Danniel Lyon, Lieutenant Maxwell Nugent, Warrant Officer Class Two Joseph Laycock and Corporal Alexander Naggs were onboard.

Unidentified human remains were found in the search zone last week.

A Royal Australian Navy dive team recovered the voice and flight data recorder — the black box — from the wreckage on Monday, the Department of Defence said.

In a statement, the department said the recovery "remains a complicated and difficult operation".

"Defence's priority remains the recovery of our soldiers and returning them to their families," it said.

"Defence remains in close contact with the families and is updating them on the operation as new details become available."

Last Thursday, the army announced human remains had been found near the search zone.

Parts of the cockpit were found 40 metres below the surface.

Australian Defence Force Chief of Joint Operations Lieutenant General Greg Bilton said the debris was "consistent with a catastrophic, high impact [crash]".

He said all communications were "normal" before the aircraft hit the water.

The Queensland Coroner has released the recovered wreckage and black box to Defence for its investigation.

The Taipan fleet has been grounded since the crash.

The transition to Black Hawkes has begun, with the ABC confirming two of the American-made helicopters had landed in Sydney two days after it happened.