Could the membership explain something to me please?
As I understand it, the a/c had reached 35K or so after departure, and then abruptly turned and descended to 12K over Malaysia on its way south. It eventually appears to have crashed at, or just beyond, the predicted fuel exhaustion radius.
Would that fuel exhaustion radius be the range at 12K, or for a B777 at a "normal" cruise altitude (i.e. 30-40K)? I imagine the radius at 12K is considerably shorter.
If it's the higher altitude, then the question in my mind is how/why did it regain altitude? If it could only be by commanded intervention, then I'm at a loss as to why it continued in a straight line.
Conversely, if it had all gone wrong an hour or so after departure, and they had headed home or to an alternate airfield, at 12K, but just not made it, why would the aircraft ascend (if it did) to reach the range that it appears to have.
Or is the range to where the search is currently centered "reasonable" at 12K?