Thursday evening ABC News reported that the plane's two communication systems were shutdown separately, citing U.S. officials. This suggests the plane did not fall out of the sky due to an unknown catastrophic failure.
Also, two pieces of information that have surfaced this past week — the Malaysia military later denied both — left some suspecting the plane was hijacked and taken to an undisclosed location. The first is that the plane changed course and was last seen traveling westward over the Strait of Malacca — and possibly out into the Indian Ocean. The second is that the plane traveled for hours after its point of last contact. But where to?Hijacking, crash into the sea
Hijackers may have either intentionally or unintentionally crashed the plane into the sea. New York City's 9/11 attacks are the best-known examples of this happening to a hijacked jetliner. If this were the case, there should be debris. Authorities have been dampening expectations that the loss of the plane was the result of a hijacking, ever since they identified the two Iranians traveling on stolen passports as likely asylum seekers.
Still, investigators are now said to be researching a Chinese Uighur man aboard the flight who had flight simulator training back in 2006.A catastrophic series of events resulting in a crash near its last-known position
Curtis says the most likely scenario is that a catastrophic series of events made it impossible to fly the airplane. “Very soon after those events occurred, the aircraft crashed somewhere in the ocean near last recorded position,” he says. This, of course, would mean we should soon find debris. But where?A catastrophic series of events resulting in a crash far from its last-known position
There's a chance the cabin crew was dealing with an in-flight emergency and had no time to radio back their location. That “wouldn't be surprising,” Curtis says. Pilots are taught to aviate, navigate, then communicate in emergency. Fly the plane, get somewhere safety, then tell the outside world of what happened. Perhaps the pilots on the Malaysia Airlines flight never got to step three of that process.
It has been reported — though the Malaysian government denies it — that the plane may have flown for hours after vanishing from radar. On Thursday, however, the White House seemed to support that conclusion when White House spokesperson Jay Carney said “an additional search area may be opened in the Indian Ocean.”Rapid/slow decompression
Explosive, rapid or slow decompression can occur from any number of unfortunate instances while traveling in an aircraft — but what happens to the people onboard during a rapid or slow decompression is notable for cases when the plane doesn't disintegrate. One of the more notorious airplane crashes in recent memory involves the Learjet crash that killed professional golfer Payne Stewart in October 1999. While investigators never concluded what caused the decompression itself, what's known is that the pilots were rendered incapacitated due to a lack of oxygen in the plane (which can occur in minutes if a cabin were to slowly lose pressure).
The pilots — and their passengers — died of hypoxia, a deadly condition caused by low oxygen conditions. The plane, however, continued to fly on autopilot for hours. It eventually ran out of fuel and crashed into a field. It's possible this happened to Malaysia Airlines flight 370, especially given recent reports that the jet's engines continued sending back data for four more hours after the point of last contact. China is searching its mainland, and India its waters, for any signs of the missing plane — that may have soared on for hours with no signs of life inside.Systemic failure
Failures could have happened in any of the systems on the aircraft. These include electric systems, communication systems and hydraulic controls. “What may have happened in the air is unclear,” Curtis says. It could have been any of these occurring individually or in a tragic breakdown, where one system's failure down affects the others.Pilot error
Pilot error has caused many of modern aviation's worst accidents. Humans drive these machines, even with a robotic assist, after all. One incident to consider when pondering the fate of the missing Malaysia Airlines plane is Adam Air Flight 574, which went down in Indonesia with 102 on board on New Year's Day, 2007, when the pilots simply lost control. That plane's debris wasn't found for a week, and it took another week to confirm it belonged to the missing jet. The majority of it had simply disappeared beneath the water.Mechanical failure
Many doomed airlines that have crashed over the years were the result of mechanical failure of the aircraft. Some, like Japan Airlines Flight 123, the deadliest single-airplane crash of all time, were the result of a previous incident that weakened the structure of the plane. Others have occurred from weakened portions of the fuselage. Some suspect a “weak spot” be the cause of the missing jetliner, especially in the wake of an FAA-issued Airworthiness Directive on Boeing 777's that would “detect and correct cracking and corrosion in the fuselage skin, which could lead to rapid decompression and loss of structural integrity of the airplane.”
If this happened to flight 370, chances are investigators would have found debris in the South China Sea. It's why they're still searching the area. It's also why investigators are considering an oil rig worker's account of seeing a burning airplane fall from the sky — despite no evidence of the plane ever hitting the water.On-board mechanical fire or explosion
“A fire in-flight, where there are flames visible outside of the aircraft, is fairly rare,” Curtis says of the possibility that the jet crashed after catching fire mid-flight. “Typically that type of thing happens after a midair collision,” he says. This theory gained credence this week after an oil rig worker came forward to say he had seen what may have been the plane soaring overhead in flames.
When TWA Flight 800 was blown to bits by what is believed to have been fumes in a gas tank, satellites searching for signs of a nuclear blast saw the fireball just off of America's eastern shore. Those satellites detected no blast over the skies of Southeast Asia. “This doesn't mean the aircraft didn't break up,” Curtis says, just that there was no notable explosion. “You can have an airline fall apart in the sky but no fireball.”Mid-air disintegration
This theory is more the result of any number of unfortunate circumstances listed above or below, and was floated in a Reuters report last Sunday. “The fact that we are unable to find any debris so far appears to indicate that the aircraft is likely to have disintegrated at around 35,000 feet,” a source told the news agency. The same source said it could have been a bomb or a mechanical incident — it was too soon to say.Far-fetchedControlled ditching
Until Chesley Burnett Sullenberger successfully landed a plane in the Hudson River, there had been few successful water landings in American aviation. “Had that been in the open ocean,” says Curtis of Captain Sully's plane, “his aircraft would have sunk after all the people got out.” The crew would have been in life preservers and life crafts, he says, and wouldn't have much else. “Assuming there was a controlled ditching in the open ocean, you could have very little in the way of floating debris — or floating survivors.”Pilot suicide
There have been a few instances of pilot suicide since the rise of the age of aviation. Luckily they're not all that common, and just 24 American pilots have killed themselves while flying their planes in the last two decades, according to FAA data reported by the Washington Post. Still, you have to ask the question. SilkAir Flight 185 and EgyptAir Flight 990 are the two commonly cited examples of this type of tragedy, with investigators concluding that the pilots deliberately caused the crashes.Explosive decompression
Aloha Airlines Flight 243 is an often-cited example of a case where an aircraft suffered explosive decompression — and its passengers lived to tell the tale. It was April 28, 1988, when a Boeing 737-297 making its way from Hilo and Honolulu suffered from explosive decompression, a result of corrosion to the airplane's body. As the plane soared high over Hawaii, a section of the roof blew out — and a stewardess was sucked out the gaping hole (she was the only fatality). Her body was never found. The aircraft landed safely less than 15 minutes later. The official NTSB report found that a passenger had actually noticed a crack in the fuselage but failed to inform anyone of the damage.A bomb
Plenty of commercial aircraft have been felled by bombs over the years. Oftentimes they tear a hole in the cargo section of an airplane, resulting in explosive decompression — or shattering the plane into pieces and sending its occupants flying out into the sky. Such is what happened over Lockerbie, Scotland when Pan Am Flight 103 was destroyed by a terrorist's bomb. 270 people were killed, including 17 on the ground. 178 were American. Had that happened with Malaysia Airlines flight, two things should have happened by now: the blast detected by satellites, and the debris found by ships. “There have been no confirmed sightings or recovery of any debris from that aircraft,” says Curtis.Pilot hijacking
Just last month the co-pilot of an Ethiopian Airlines flight hijacked his own plane by locking the pilot out of the cockpit. He then flew the plane to Geneva, seeking asylum. The plane had been headed for Rome. Ethiopian Airlines claimed the plane had been “forced to proceed” there. One of the pilots of Malaysia Airlines has raised questions of his behavior for inviting passengers into the cockpit in the past. Some observers also question why he had built a flight simulator in his home — was he practicing for something? If this were the case, surely the plane would have turned up by now. But it hasn't.Military missile
Commercial aircraft have been targeted by militaries in the past, most notable Iran Air flight 655 in 1983 and Korean Air flight 007 in 1988. But did it happen again in the skies over Malaysia or Vietnam? Doubtful, says Curtis, the aviation expert who has been tracking the story all week. “There is no indication of that happening,” he says. “Possible — but no indication.”
This article originally appeared on Mashable .