Have a friend who recently retired as a pilot from a major airline. He has flown the Boeing777 and has a theory along with some other pilots on where MH370 ended up, and why. The interesting thing is that of all the theories I heard on TV for weeks this one never came up.

Without trying to remember every detail of where and when all the components failed, here it is. First there was a battery fire in a aft compartment under the passenger compartment. Before the fire suppression system activated, the fuselage was breached and they lost pressure (and oxygen). The crew could not descend quick enough to save themselves or the passengers. The plane continued on autopilot (this pilot thought if it was not set by crew then it would take a meandering course) then when fuel was gone, a ram air turbine in the belly of the plane generates enough power to keep the computers and servos operational. Even without engines the 777 would automatically trim the flaps and attempt a ideal glide angle all the way to the water. If the conditions were right. the plane could have remained intact on water landing and went to the bottom. Accounts for loss of contact, strange flightpath and no debris to be found.

Just a theory from someone who has flown these things. Be warned though, this pilot doesn't think TWA Flight 800 that exploded on its way to France as a accident either.