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Old 12th Jan 2016, 17:56
  #74 (permalink)  
ika
 
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Originally Posted by darkbarly
In other words you mean less elevator authority ika? Low IAS at cruise level methinks.
What sorry dog said! Sorry for not being clearer; air may be thin and IAS not that high at 33,000 feet but pretty soon after you start diving earthwards IAS and control authority will go up. There's a general surmise (not conclusive) from the images and other data that it went in fast, nose-first, in one piece rather than a stall or in flight break-up. At some point, let's say 15,000 feet, assuming (for this only) pilots were not incapacitated or disoriented, heading nose down at a fair pace, if one had functioning controls one would expect to pull up as far as possible (and as necessary throttle back). I don't know about others but if controls worked but a forward c of g hindered pull up, faced with the grim choice of the certainty of what the looming ground means versus the possibility of overstressing the airframe I'd probably spend my last 60 seconds pulling hard back until either the nose stopped pointing at the ground or the elevator came off! Since they haven't located separate debris suggesting elevator detachment/damage it suggests to me that a c of g issue alone is unlikely. Some form of control issue, whether trim runaway, multiple hydraulic failure etc and/or a crew incapacitation issue must be considered, in my humble view. But feel free to disregard. I suspect most will agree, apart from the tragedy, is that it is both very curious and, unless the memory proves recoverable, unlikely we will know.
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