Your hours' analogy should be more like months.
MH370 has no survivors. There is no magical floating boat for 3 years waiting to be found on some island.
What? They would have died within hours of exposure even if they'd survived impact.
I'm saying they are 100% dead but in the absence of bodies and the plane, we don't know about the precise circumstance so my only point was to back up the criticism of the 'definitely the pilot that did it, case closed'