CANBERRA, Aug. 1 (Xinhua) -- A leading air crash expert has said missing Malaysia Airlines fight MH370 was likely to have been in controlled flight as it hit the water, giving life to the theory it was brought down by a rogue pilot or hijacker.

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

Vance said the only way to extend the flaperon, something which happens when a plane is attempting a landing, was for the pilot to engage a switch, something which is unlikely to have occurred during an sudden disaster.

"You cannot get the flaperon to extend any other way than if somebody extended it," Vance told the Nine Network's 60 Minutes program overnight.

"Somebody would have to select it (in the cockpit)."

Vance said, from photos released of the flaperon, there was evidence to show the aeroplane hit the water at a controlled speed, pointing to it being a "human engineered event."

"Somebody was flying the aeroplane into the water... There is no other alternate theory that you can follow of all the potentials that might have happened. There's no other theory that fits," he said.

"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."

Meanwhile, Australian Transport Safety Bureau (ATSB) crash investigator Peter Foley said there was a possibility that someone was in control of the plane as it went down.

"There is a possibility there was someone in control at the end and we're actively looking for evidence to support that," he said on Sunday night.

He admitted that if it was brought down by a "rogue" pilot, the wreckage could be outside the parameters of the Australian-led 120,000 square kilometer search zone. The search for the Boeing 777 is scheduled to end in coming weeks, considering less than 10,000 square kilometers is yet to be searched.

"If you guided the plane or indeed control-ditched the plane, it has an extended range, potentially," Foley said.

MH370 was a scheduled passenger flight bound for Beijing from Kuala Lumpur. There were 239 passengers and crew on board.