CANBERRA • A leading air crash expert has said the missing Malaysia Airlines Flight MH370 was likely to have been in controlled flight as it hit the water, supporting the theory that it was brought down by a rogue pilot or hijacker.

Canadian air crash expert Larry Vance told Australia's Nine Network there was no other way to explain why a wing section called a flaperon, found off the coast of Madagascar a year ago, was "extended", meaning it would have been in controlled flight as it hit the water.

Mr Vance said the only way to extend the flaperon, something that happens when a plane is attempting a landing, is for the pilot to engage a switch, which is unlikely during a disaster.

"You cannot get the flaperon to extend any other way than if somebody extended it," Mr Vance said on Nine's 60 Minutes programme on Sunday... Somebody would have to select it (in the cockpit)."

He said photos of the recovered flaperon showing a jagged edge - suggesting high-pressure water erosion - provide evidence that the plane hit the water at a controlled speed, pointing to it being a "human-engineered event".

"The force of the water is really the only thing that could make that jagged edge that we see (on the flaperon). It wasn't broken off. If it was broken off, it would be a clean break."

Australian Transport Safety Bureau crash investigator Peter Foley has also told 60 Minutes there was a possibility that someone was in control as the plane went down.

He agreed that if it was brought down by a "rogue" pilot, the wreckage could be outside the parameters of the search zone.

XINHUA