· Malaysia Airlines plane debris possibly found near Vietnam
· Two on board lost flight were on stolen passports
· Six Australians on Malaysia Airlines flight
· Tears and anger as relatives wait for news
The disappearance of a Malaysia Airlines jet on Saturday over the South China Sea has left aviation experts puzzled. What caused the airliner to disappear, almost without trace, two hours into its six hour flight to Beijing?
Whatever happened to flight MH370, experts know it happened quickly and left the pilots no time to place a distress call.
Until the aircraft is found, investigators will sift through the evidence as it arrives, building on theories which range from a catastrophic mechanical failure to something more sinister, like terrorism.
If there was a mechanical problem – or even the shutdown of both of the plane’s engines – the pilots likely would have had time to radio for help.
The lack of a call “suggests something very sudden and very violent happened”, said William Waldock, who teaches accident investigation at Embry-Riddle Aeronautical University in the US.
Instead, it initially appears that there was either a sudden break-up of the plane or something that led it into a quick, steep dive.
There are unconfirmed reports the Vietnamese Navy radar recorded the plane crashing into the ocean about 250km south of the Phu Quoc Island tourist report.
‘Turn back’ theory
However the picture changed slightly as Malaysian authorities indicated the aircraft appeared to have sought to turn back, albeit they were puzzled by the lack of communication from the cockpit.
“There is a distinct possibility the airplane did a turn-back, deviating from the course,” Malaysia’s air force chief, General Rodzali Daud said.
“One of the possibilities is that it was returning to Kuala Lumpur.”
Some experts even suggested an act of terrorism or a pilot purposely crashing the jet.
“Either you had a catastrophic event that tore the aeroplane apart, or you had a criminal act,” said Scott Hamilton, managing director of aviation consultancy Leeham Co. “It was so quick and they didn’t radio.”
No matter how unlikely a scenario, it’s too early to rule out any possibilities, experts warn. The best clues will come with the recovery of the flight data and voice recorders and an examination of the wreckage.
Just nine per cent of fatal accidents happen when a plane is at cruising altitude, according to a statistical summary of commercial jet aeroplane accidents done by Boeing.
Capt John M. Cox, who spent 25 years flying for US Airways and is now CEO of Safety Operating Systems, said that whatever happened to the Malaysia Airlines jet, it occurred quickly.
One of the first indicators of what happened will be the size of the debris field. If it is large and spread out over tens of miles, then the plane likely broke apart at a high elevation.
That could signal a bomb or a massive airframe failure. If it is a smaller field, the plane probably fell from 35,000 feet (10.6km) intact, breaking up upon contact with the water.
“We know the aeroplane is down. Beyond that, we don’t know a whole lot,” Cox said.
Some of the possible causes for the plane disappearing include:
Catastrophic failure of the airframe or engines
Most aircraft are made of aluminium which is susceptible to corrosion over time, especially in areas of high humidity.
But given the plane’s long history and impressive safety record, experts suggest this is unlikely. The BBC noted Malaysia Airlines has been battling financial uncertainty and has been losing ground to low-cost carriers, with possible aviation safety implications.
Planes are designed to fly though most severe storms. However, in June 2009, an Air France flight from Rio de Janeiro to Paris crashed during a bad storm over the Atlantic Ocean. All 228 passengers and crew aboard died. The pilots never radioed for help.
But in the case of Saturday’s Malaysia Airlines flight, all indications show that there were clear skies.
Curtis said that the pilots could have taken the plane off autopilot and somehow went off course and didn’t realise it until it was too late. The plane could have flown for another five or six hours from its point of last contact, putting it up to 4800km away. This is unlikely given that the plane probably would have been picked up by radar somewhere.
Failure of both engines
In January 2008, a British Airways 777 crashed about 300 metres short of the runway at London’s Heathrow Airport. As the plane was coming in to land, the engines lost thrust because of ice build-up in the fuel system. There were no fatalities.
Several planes have been brought down including Pan Am Flight 103 between London and New York in December 1988. There was also an Air India flight in June 1985 between Montreal and London and a plane in September 1989 flown by French airline Union des Transports Ariens which blew up over the Sahara Desert.
Groups considered by world governments to be terrorists do operate in the southern Philippines and in parts of Indonesia and Malaysia.
Some desperate Uighur people in western China have resorted to terrorism to push their claims for greater autonomy, however no-one has yet claimed responsibility for this disaster. The US law enforcement agency, the FBI, has confirmed to CNN that its agents in Kuala Lumpur are monitoring the situation closely.
There are also reports at least two, and possibly as many as four, people on board the flight were travelling on stolen passports. Malaysian law enforcement authorities have also confirmed they are investigating any likely links.
There were two large jet crashes in the late 1990s that investigators suspected were caused by pilots deliberately crashing the planes.