The search for a helicopter pilot missing off Western Australia's Pilbara coast for almost two days has been suspended.
The chopper ditched into the ocean 30km from the mining export hub of Port Hedland around midnight on Wednesday.
A 44-year-old trainee pilot, who was reportedly flying the helicopter, remained missing on Friday night despite a search of more than 1000 square kilometres.
A second pilot, believed to be aged 64, was rescued from a life raft shortly after the crash.
In calling off the search, the Australian Maritime Safety Authority said, "weather conditions for searching were good and there was a high probability that a survivor in the water would have been detected".
The chopper crashed while approaching the China-bound bulk carrier MV Squireship to pick up a marine pilot.
AMSA spokesman Craig Condon earlier on Friday told reporters the helicopter became inverted almost instantly, and praised the 64-year-old's response.
"Without doubt his training kicked into gear. He has done underwater escape training, he's managed to free himself and activate his beacon," Mr Condon said.
"He also let four flares off, which greatly assisted in his retrieval.
"Indications are at this stage that he had not sighted his colleague and did not hear from his colleague as he exited the aircraft."
The two pilots are employed by Aviator Group subsidiary Mackay Helicopters, which specialises in marine pilot transfers between ships.
"Aviator Group is deeply concerned for the missing pilot, and is in contact with his family," the company said in a statement.
Police divers will plan a search for the helicopter's wreckage while the transport safety bureau continues to investigate the crash.
