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The last phase of flight MH370, when the jet with 239 people on board apparently flew for some seven-plus hours until it ran out of fuel, is consistent with the possibility the aircraft flew on autopilot with everyone on board dead or incapacitated.
1. The change of course, the routine last voice communication with air traffic control, the switching off of the aircraft's transponder and the disabling of the automatic data reporting system all point to deliberate acts by someone familiar with the sophisticated plane, perhaps a pilot acting on his own or under coercion. However, a suicidal pilot usually dives for the sea quickly; hijackers want to go somewhere; terrorists hoping to use the plane as a guided missile need targets within range.
2. We know that the plane kept flying for seven more hours after its transponder was turned off because the plane's communications system was "handshaking" with a satellite high above the Indian Ocean every 30 minutes or so – much like a cell phone checks in with a nearby tower even if it isn't in use and its data function has been turned off.
3. One possibility is a hijacking gone awry, followed by hypoxia of all.
A window seal failure or a bullet blast in the thin aluminum fuselage for example, can cause an aircraft to lose its pressurization, thus rendering the cabin air unfit to breathe. Hours of inexplicable silence from a modern jet, still flying, matches previous cases of hypoxia.
4. The air masks that fall from overhead in modern jetliners supply only a few minutes of life-sustaining oxygen. When an aircraft loses its artificial atmosphere, pilots must dive the aircraft down to a few thousand metres above the surface where the air is rich enough to breath or everyone will die. There is no indication MH370 did such a dive.
Text by Paul Koring, graphic by Matthew Bambach