A new theory proposed by a U.S. pilot to explain the disappearance of Malaysia Airlines Flight MH370 claims that the plane was filled with deadly carbon monoxide from burning lithium-ion batteries on board before it crashed into the southern Indian Ocean. Since the disappearance of the jet in March 2014, which triggered an unprecedented ongoing search, several theories have emerged claiming to explain what may have happened to the plane.

Bruce Robertson, in an analysis posted on his website, claims that pilot Zaharie Ahmad Shah succumbed to the fumes, but co-pilot Fariq Abdul Hamid survived long enough to turn the plane around and place it into a descent in an attempt to make an emergency landing. However, Fariq also reportedly succumbed to the carbon monoxide, leaving the Boeing 777-200 on autopilot for several hours until its fuel ran out and it crashed “into the Southern Indian Ocean west of the Zenith Plateau, west of Exmouth Australia,” according to Robertson.

He also raises questions about the location of the current search area where authorities believe the plane may have crashed.

“The Zenith Plateau area was the site of the original search in March and April, 2014, due to underwater locater pings being detected in the vicinity,” Robertson writes, in his report. “While the ping yield valuable clues as to the MH370’s whereabouts, the search area is soon discarded due to some very impressive but difficult to challenge mathematics that turned out to be wrong. Much too much time and money has been wasted on a fruitless search in an area much further southwest, due west of Perth.”

A few weeks after the plane’s disappearance, Malaysia Airlines reportedly confirmed that the passenger jet had been carrying lithium-ion batteries in its cargo bay.

Flight MH370 went missing on March 8 with 239 people on board while on its way from Kuala Lumpur to Beijing. A massive search operation, headed by Australia, has so far failed to locate the plane. About 19,000 square miles of a planned 46,000-square-mile search zone -- located about 1,100 miles off the western coast of Australia in the southern Indian Ocean -- has been scoured.

The search effort, which is jointly funded by Malaysia and Australia, has continued for over a year, and has become the most expensive search operation in commercial aviation history.

Robertson also said in his report that the jet's disappearance is not part of a conspiracy but a “simple industrial accident that took a while to play out due to automation trying to save the situation.”