A Pilatus PC-9/A comes in for a landing at RAAF Base Pearce in Perth, Australia, Wednesday, March 26, 2014. RAAF Pearce is accommodating six nations Australia, New Zealand United States, Japan and Korea making this joint venture one of the largest maritime search operations in history to find debris from the missing Malaysia Airlines Flight MH370
Where information is scarce, speculation rushes in. As the hunt narrows for wreckage and the precious "black box" of flight data and recordings, there has been little progress in penetrating the core mystery – why did Malaysia Airlines flight MH370 veer radically off course and fly out across one of the world's most pitiless seas?
The hope of understanding what really happened aboard MH370 is growing fainter. Even if wreckage is confirmed and an underwater salvage to recover the voice and data operation is successful, questions are likely to remain unanswered. For example, the cockpit voice recorder overwrites itself every two hours so it would not have captured information at the crucial point when the flight changed direction.
The leading theories so far include a crisis that punctured the cabin, incapacitating the pilots by oxygen starvation before they could dive to safe altitude. Other speculation, drawing on the shutdown of communication and detection systems, focuses on takeover of the plane for malign purposes, whether by hijacker or a pilot bent on spectacular self-destruction.
Here are five other factors fuelling the speculation.
1. The mystery woman
Captain Zaharie Ahmad Shah was the man with the greatest opportunity to redirect the flight. He received a phone call a few minutes before take-off. It was made using a mobile phone that was purchased by a woman who did not provide proper identification. Was it a final goodbye? Or final instructions?
2. The shadowy island of Diego Garcia
The early news that Captain Shah had constructed a sophisticated flight simulator in his own home has prompted much speculation about his thinking, especially after authorities stated that some data had been deleted from the system. The unsourced reports claimed that the simulator held a program for practising a landing at Diego Garcia, the British possession which the United States has used as a forward base for naval and air power in southern Asia. Since the 9/11 attacks on the U.S., Diego Garcia has been regularly cited as home to one of the CIA's "black sites" for secretly holding those captured in the global war against Al-Qaeda and its sympathizers.
3. The tech angle
Among the 239 passengers and crew on MH370 were 20 employees of Freescale Semiconductor, which the Texas-headquartered company has confirmed. It's a fact that draws theorists through the sheer number of people affiliated with one organization, and that organization's history and status as a creator of cutting-edge technology. Before it was spun off from Motorola in 2004, the unit was at the forefront of the digital revolution, inventing and supplying critical components for everything from ordinary radios to the communications and transponder links between Earth and Apollo 11, the first craft to land a human being on the moon. Freescale's R&D involvement in everything from "swallowable" medical computers to location tracking for mobile devices and less-documented military research have even led some to speculate that the plane was "cloaked", or the aircraft the target of an effort to steal knowledge.
4. The precious cargo
Was MH370 carrying something unusual? Something valuable or dangerous? According to various media reports, Malaysia Airlines has not released a full and detailed manifest of the cargo. This may not be unusual, but it has certainly opened another arena for speculation.
5. The passengers are still alive
For all the evidence that the flight was lost at sea, the behaviour of some passengers' mobile phones gave rise to speculation that they were still alive, and therefore that the plane must be safely on the ground in hiding. That's because when some of the phones were called by relatives, there was ringing heard before going to voicemail. In fact, not all such calls do go straight to voicemail, especially if the phone's battery is destroyed.
Editor's note: An earlier version of this story incorrectly stated that the flight's data recorder overwrites itself every two hours. In fact the data recorder continues to work for much longer. This is now the corrected version of the story.
With a report from Rick Cash