Countless theories have surfaced about the disappearance of Malaysia Airlines Flight 370 nearly two weeks ago. Even the most logical hypotheses have holes and no scenario solves this mystery. A look at some of the leading theories — and their flaws.


Investigators are looking at the histories of Capt. Zaharie Ahmad Shah and co-pilot Fariq Abdul Hamid. Zaharie had built his own flight simulator at home, unusual but not out of the norm. Why suspect the pilots? The plane's transponder stopped signaling its location to controllers at the perfect moment: the handoff from Malaysia's controllers to those in Vietnam. The plane abruptly turned and then kept flying for up to seven hours. The way key communication and tracking devices in the cockpit were disabled — at different times — also places suspicion on the pilots. The idea is not unprecedented. A 1997 SilkAir crash and a 1999 EgyptAir crash likely were the result of deliberate pilot actions.


This theory was prominent after it was discovered that two Iranians on board had stolen passports. Investigators haven't linked either to terror groups. Ever since 9/ 11, it's much harder for an unauthorized person to enter the cockpit. Intelligence agencies say they haven't noticed any related chatter in terrorist circles.


Experts initially suspected that something sudden happened. Perhaps a bomb on board, or a failure of the engines or airframe. But if that were the case, debris would have been found in the spot where the transponder went off. If there was a sudden breakup, pieces of the plane would have been visible on radar.


A fire could have knocked out communications equipment and prevented crew members and passengers from calling for help. Some people have speculated that smoke incapacitated the pilots. It's possible, but flight attendants and passengers would have had time to try to enter the cockpit and take control of the plane.


A decompression could have killed everyone on board. If oxygen levels dropped, a warning would have alerted the pilots to descend below 10,000 feet, where there is enough oxygen to breathe. If the plane depressurized and killed its occupants, which happened on golfer Payne Stewart's jet in 1999, that would explain the silence from crew and passengers. But the plane should have kept flying automatically and been visible on radar.


It's possible that somebody landed the plane at some remote airport. Maybe they want to hold the passengers hostage. Maybe there was something of value in the cargo hold. Maybe terrorists have the plane. Those scenarios all have holes. A very skilled pilot would have to land the plane at a small airport. They would have to dodge several nations' radar systems.


In July 1988, the U.S. Navy missile cruiser USS Vincennes accidentally shot down an Iran Air flight. In 1983, a Korean Air Lines flight was shot down by a Russian fighter jet. There is no evidence that Flight 370 was brought down by a government.

associated press