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Old 3rd Sep 2011, 23:39
  #3431 (permalink)  
Lyman
 
Join Date: Aug 2011
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TD

At ~2:10:02, the a/c is VS 1000fpm UP. The PITCH is ND 4 degrees from cruise.

This is exquisitely consistent with entry into a robust Updraft. If this upwelling has a velocity of 60 knots, we take 6000 fpm as the new airmass vector to add to the horizontal of cruise. This produces a distinct reduction in air speeds. All that is required is a reduction of 30 knots in the sensed a/s in less than one second, and the ADs get tossed.

To cause a 200 tonne a/c to climb @ 1000fpm might require an updraft of such a value, quite high. Then we can add to the a/c Attitude the free moment arm of the Horizontal Stabilizer, elevators. The mass will not lift immediately, but it will articulate longitudinally, ie: tail UP, Nose DOWN.

Those two bumps at the tail end of a/p duty are interesting.

Thanks for your reply

mm43... I continue to try to put together the airframe responses prior to and during the PF's capture of the controls. Obviously, it is here that I will look with great care, firstly because BEA have left it unaddressed, and the data is sparse; Secondly, the rest of the released data and all the one sided rhetoric shouts: SORTED! I don't think so, but it is largely irrelevant to me, the fascinating discussions are a follow on to an almost immediate LOSS of control, so this is where the Grail must be......

cheers
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