A section of wing from the missing aircraft shows evidence it was extended when the plane hit the water, proving that someone was in control of the aircraft, air crash expert Larry Vance says.
"There is no other alternate theory that fits," Mr Vance, who helmed the investigation into the downing of Swissair Flight 111 in 1998, told Channel Nine's 60 minutes programme on Sunday.
Flight MH370 disappeared on March 8, 2014 with 239 passengers and crew en route to Beijing from Kuala Lumpur.
The current search operation, led by Australia, has been based on the theory that the jet was not under human control when it crashed after it veered off course and headed south over the Indian Ocean.
Mr Vance, however, believes that a small section of the wing, called flaperon, found in Madagascar last summer, shows "definitive evidence" that it was extended at the time of impact. Only a person can activate the extending.
"Somebody was flying the airplane at the end of its flight," Mr Vance told 60 Minutes' Ross Coulthart.
The expert added that the failure to find floating debris and lifejackets would fit the theory of a slow, controlled landing.
"Somebody was flying the airplane into the water.
"There is no other alternate theory that you can follow.
"Of all the potentials that might have happened, there is no other theory that fits," he said.
Australian transport safety bureau crash investigator Pete Foley agreed the crash could have been the work of a rogue pilot. He said analysis from French authorities showed it was possible the plane was in a "deployed state."
The flaperon is in the hands of the French, and Malaysian investigators have been unable to take possession of it, a year after its discovery.
"I think it’s been a frustration for the investigation," Mr Foley said.
He conceded that if the plane was piloted until the end, it could have landed outside the current search area: "There is a possibility there was someone in control at the end and we’re actively looking for evidence to support that."
Mr Vance said flights which crash into the ocean while out-of-control in effect explode on impact, creating millions of pieces of debris.
In MH370's case, only a handful of wing segments have been found so far, despite more than two years of ocean currents which should have pushed more debris to land.
"I think the fuselage is intact for the most part, and is on the bottom of the Indian Ocean," Mr Vance said.
The the discovery of the flaperon, which showed damage consistent with the force of water, should have prompted experts to conclude the crash was caused by a rogue pilot, the expert believes.
“Everybody should then have concluded in my opinion that this was a human engineered event, there’s no other explanation,” Mr Vance said.
Meanwhile a large wing part believed to be from the missing plane was brought to Canberra for analysis after it was found by locals on Pemba Island off the coast of Tanzania in June.