There would have been an explosive loss of pressure at 35,000ft when the SATCOM antenna array disintegrated. The pilots, while disoriented would have done two things, try to take the plane down to below 30,000 feet and try to turn around to the nearest airport for an emergency landing. This is corroborated by the turnaround statement that was tracked by the Military Radar. This also explains why sites like FlightRadar24 and Flightaware lost the flight at the Igari checkpoint. ADS-B isn’t able to track aircraft flying below 30,000ft, but the plane still would have appeared on DCA and Military radar.
Now, the explosion would have taken out the entire SATCOM antenna array, so if the pilots did indeed try to send out a distress call over their normal communications channels, it would not have gone through. However they might not have been aware that their SATCOM antenna array is gone. There could have switched to other communication channels (VHF etc), but they might have been either disoriented, or they just felt that all communications were down. Its hard to speculate their condition and if they were able to get their oxygen masks on in time. Hypoxia (due to the lack of oxygen) can set in very fast, impair cognitive functioning of the brain and incapacitate a person in a short amount of time. Passenger oxygen masks on the 777 do not deploy until cabin altitude exceeds approximately 13,500, and passengers were likely unconscious by that time if it was a slow decompression.
The pilots could have tried to turn back and land at Kota Bahru Airport, but if they were incapacitated, they could have put the plane in autopilot or one of the autothrottle hold switches and hope they would recover and then take control of the plane. This would corroborate with the story of the pilot enroute to Narita who tried to contact the plane on all channels, and only receive faint mumbling from either the pilot or the co-pilot. I don’t see any reason why a pilot would lie to the media under circumstances like this. There were also a number of reports from people who claimed to have seen a low flying aircraft across places in Kelantan, some claiming that its tail wing was on fire at around 2am.
Update:
Another possible explanation for sudden in flight depressurization arising out of this particular airline, and from what otherwise would be simple but incorrect methods of paint removal and maintenance.
there is a huge amount of shipping and fishing traffic around Pulau Perak. If the plane went down in that area, there would of been a boat load of radio traffic...
ReplyDeleteJust a note regarding the altitude issue, hypoxia shouldn't have been an issue if the oxygen system was working correctly. The masks drop automatically when there is a preset difference between cabin pressure and the outside air pressure. It can also be triggered manually by the pilot. Mount Everest is 29,000 ft high and some people have climbed it without oxygen. Most aircraft can fly up to 12,000 ft without oxygen. So it would have been very likely that the pilots were not unconscious due to lack of oxygen. As long as the pilot started descending straight away and the masks were deployed, there should be no reason that they would have all blacked out, Unless there was a fire or bomb on board and these systems became inoperable.
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