Cruise: max pressure differential
Explained in simple words.
As soon as cruise height was reached the problem started, critically this was a sudden event likely linked to pressure: any loss of structural integrity (e.g. windscreen or other) started in coincidence with reaching max cabin pressure differential with the outside pressure. This timing cannot be a coincidence, the rest is hypoxia of all those on board whilst pilots being unable to do anything else except start descending; heading and speed remained constant until impact. No communication, aircraft continues with pre-set heading and speed: this is typical behaviour of aircraft with unconscious pilots in cockpit. It has happened before.
I have no doubts this was hypoxia (or unconscious pilots for any other reason). The fact that ATC lost contact and it quickly happened shortly after reaching altitude it would reinforce the hypoxia theory as a consequence of decompression, possibly caused by structural failure. I would exclude external factors at that altitude, the problem coming up at 1030/1031 time would confirm internal/external pressure extreme difference as likely trigger of decompression, in coincidence with max stress on structure, loss of fuselage integrity (aircraft still perfectly able to fly) with subsequent rapid hypoxia. To react to a decompression at that altitude is not as easy as thought or simulated, especially if cockpit environment is disrupted by the cause of the decompression (e.g. air coming in at very high speed). I have no doubts that these were excellent pilots who were not given a chance to follow standard simulator procedures, which can never cover all "real" scenarios.
Last edited by ILS27LEFT; 25th Mar 2015 at 18:46.
Reason: correction