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Old 19th Sep 2009, 20:24
  #4421 (permalink)  
Machinbird
 
Join Date: Jul 2009
Location: Not far from a big Lake
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The Energy Wasn't Dissipated
That's the problem. With enough elevator control power and no computer between you and it to restrict G, you can yank the nose up without changing the velocity vector much at first. The pitot won't read much airspeed because it's looking forward and not down, but you're still going down at almost the same rate of descent, which is consistent with a high angle of attack.
T-Turtle, I have participated in a few accident investigations including one where the pilot yanked the nose up to avoid flying into the ground (to no good effect) and I can state pretty conclusively that is not what happened with AF447. Further, although I may be going out on a limb because BEA has not made a statement in this regard, the character of the damaged components I have seen pictures of and the reported condition of the human remains indicates a low speed collision with the water below 200 knots. Believe me, that energy was dissipated. If you would like to discuss further, drop me a PM.
Further, on an A330, there is no direct connection between the side stick controller and the control surfaces. You only give the computer "hints" at what you want it to do and it processes those hints in accordance with the current control law it is operating in. And if there is no power to the computers-there is no control.
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