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Old 16th Mar 2014, 19:45
  #645 (permalink)  
Chris Scott
 
Join Date: Jan 2008
Location: Blighty (Nth. Downs)
Age: 77
Posts: 2,107
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Quote from roullishollandais:
What is still unknown is the altitude read on the altimeter on the cockpit

That is correct, strictly speaking, for two reasons:
(1) there is no video of the cockpit altimeters;
(2) we only have the testimony of the pilots that they had set their altimeter sub-scale settings to the transmitted QFE of 984.

However, as you know, it is a simple process to convert the DFDR readings of pressure altitude ("FINF") to the reading of an altimeter set to 984 hPa, simply by subtracting 808 ft.
For those who have not already done that, here are the readings at one-second intervals,
starting at TGEN 310 (t -24), and finishing at TGEN 334 (t -0):
126, 115, 111, 104, 101, 89, 85, 75, 70, 69, 68, 61, 60, 60, 60, 54, 54, 56, 53, 51, 52, 55, 56, 60, 56.

As I have stated in an earlier post, it appears that the a/c levelled off at 61 ft on the QFE at about t -13, gently lost indicated height from about t -10, and then recovered most of it by t -1. It is likely, however, that the accuracy of the readings available to the crew would have suffered from increasing position-error in the last seconds, because of the high AoA. Also, the static ports are between the cockpit and the CG, so the increasing pitch-attitude means the CG is increasingly lower than the static ports (whereas the pilot eye -height is increasingly higher).
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