The crash, which killed three people, including pilot James Wong, occurred off the Western Australian coast

Investigators estimate it will take months to understand the cause of a seaplane crash off the Western Australian coast that killed three people and injured three others.

The aircraft carrying seven people is believed to have struck a small limestone outcrop near the popular holiday spot Rottnest Island, west of Perth, about 4pm on Tuesday.

The Cessna 208 Caravan 675 plunged nose-first into the water near Thomson Bay, killing pilot James Wong, 34, a 65-year-old Swiss woman and a 60-year-old Danish man.

Investigators were working to retrieve the sunken wreckage to uncover further details about what went wrong during the flight, especially from the recording devices that may have captured its final moments.

“Those few seconds of flight, what went wrong and, most importantly, then what are the sorts of things we can recommend to lessen the likelihood of this occurring again,” the Australian Transport Safety Bureau chief commissioner, Angus Mitchell, told ABC News on Thursday.

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There may also be mobile phones from the passengers on board to help the investigation, Mitchell said.

The complex investigation will also investigate the engine pitch, the aircraft’s history, maintenance, the weather and standard operations over Rottnest Island.

“There’s a whole range of things to put together to give us a better idea of that sequence of flight and then what went wrong,” Mitchell said.

“That will take us time to go through all the evidence.”

He said once investigators have all the evidence – which could take many weeks – they will begin forming hypotheses of the cause of the crash, and there could be multiple possible scenarios.

“That takes some time for us,” Mitchell said. “We need to get these things right if we’re to make recommendations that have far-reaching effects.”

He hopes there will be a preliminary report within two months.

The owners of the seaplane say they are distraught over the tragedy, particularly the loss of their pilot, who was a “deeply cherished” team member.

“Our deepest and sincere condolences are with their families and friends,” Swan River Seaplanes company director Kristy Bailey said.

Police divers pulled the three bodies from the wreckage eight metres below the water’s surface on Tuesday night after a frantic search during the afternoon.

The survivors include a 63-year-old Swiss man, a 63-year-old WA man, a 65-year-old WA woman and a 58-year-old Danish woman.

A 200m exclusion zone was in place while investigations and salvage operations continued.

Some wreckage from the seaplane, which broke up during the crash, has been brought ashore.

Source: www.theguardian.com