Hi all,
I've been lurking on here for quite a while but I though I might post on a though I had after reading all the posts on here and the report yesterday.
First off I'd just like to say I am not a pilot and I dont work in civil aviation. However, I am an engineer with 10 years experience and an aerospace background. Several years back I took part in 2 crash investigations regarding unmanned military aircraft.
The indications seem to be that the aircraft went into the sea at a high rate of speed but also it would seem it lost considerable altitude in a very short time. This does not seem consistent with the fact the aircraft met the ground in one piece - how could so much altitude be lost so quickly?
My suggestion is that the pitot tubes could have failed (iced up) quite some time before the accident or any indication of a fault. Suppose all three tubes failed at approximately the same time holding the readings for cruising altitude and speed. The consistency in readings may have got past the computer which may not have raised the fault.
In this eventuality is it possible that the auto pilot could have continued to operate on false information leading to gradual loss in altitude over a relatively long period and hence this was not noticed by the crew or ATC which would get altitude from the aircraft via secondary radar.
The pitot fault messages could have been caused as the pitot tubes began to de-ice as a result of the warmer air at lower altitude. If they did not de-ice at the same time this would cause the disagreement which initiated the fault.
After that the crew would have had a high workload and very poor situational awareness due to the instrumentation fault. Perhaps the presence of weather also blocked out the moonlight making any visual cues difficult to see.
Could the crew have flown into the sea at high speed if they had much less altitude than expected? Maybe the tail first impact suggests the only saw the sea at last minute and pulled up resulting in the tail striking the water.