"It could have drifted more than 500km", says Australian professor

If the debris spotted in the southern Indian Ocean is found to be from the missing plane, it could have drifted more than 500 kilometres from the crash site, a Perth oceanographer said.

Professor Chari Pattiaratchi, of the University of Western Australia, said the searchers face the world’s most treacherous seas, and a wreckage recovery operation would be extremely challenging.

The 23,000-square-kilometre search area is in a body of water known as the Roaring Forties, where strong circumpolar westerly winds blow.

Waves of four metres to five metres are constant, but can swell to more than 10 metres during a storm.

”It is as hostile as it can get,’” Prof Pattiaratchi told ABC radio.

”Because of the strong winds, the waves are always breaking, so it’s white-capping all the time, so to distinguish between whether it’s part of the debris or a wave breaking ... it is quite a challenging system.

”Water depths are up to five kilometres deep, so even if you find something, it’s a big challenge to recover it.”

He said there were only five or so vessels in the world - remotely operated vehicles or submersibles usually tethered to a ship - that could reach such depths.

If the debris captured in images taken on March 16 and publicly revealed yesterday were found to be part of the missing aircraft, the pieces could have drifted more than 500km to the east of the crash site, Prof Pattiaratchi said.

”We actually have computer models that we can try to run backwards in time to be able to find out where the debris may have come from.”