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Old 10th Apr 2011, 19:28
  #3270 (permalink)  
henra
 
Join Date: May 2010
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Originally Posted by sd666
Related to this, some posters have expressed surprise that the wreckage has been found to close to the LKP. There's nothing surprising about it. You don't know what happened between the LKP and impact. There is no reason whatsoever to suppose that the aircraft's descent was in any way continuous, be it a dive, flat spin, continuous turn or whatever.
I don't know if this refers to my statement.
If yes please read my post carefully. That should explain why I'm a bit surprised that it is that close.
If we assume that the aircraft at LKP was still at cruise speed (which can be assumed from the average speed between the two last known positions since it was in line with the average speed between the previous ones) then it had massive kinetic and potential energy at that point. So much energy is not shed that quickly in an airliner. Even a max pull- up at LKP should require 20 - 30s before stalling the plane (at that point I assume it was not yet in Alternate 2 which might allow for an accelerated stall). Stalling should happen somewhere around 350 kts ground speed. At that point it will already have travelled ~4nm and it will still be traveling at that speed.
Being so close to LKP requires some kind of course reversal at a certain point.
It is defnitely not impossible, but in an upset any other direction would have been equally as likely or even more so.

And considering the verical velocity in these 5 mins it does not seem that it was one single continuous drop.
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