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Old 1st Aug 2011, 02:34
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takata
 
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Originally Posted by Bearfoil
The traces tell this?
It seems that autothrust reduced N1 from ~100% down to 85% just before disconnection (reduction caused by turbulences or Mach selected, diconnection by UAS) and it stayed there until it was unlocked by the pilots (~0210:25 -> CLB).
This caused at first a pitch down of about 3°, down to zero or slightly below (~0210:00 - 0210:05)... which could have delayed the aircraft response to PF NU orders.
Thrust increased to CLB between 0210:25 and 0210:35, from 85% to 100+, it would have added some pitch up before the PF tried to reduce aircraft V/S.
N1 was reduced again to 85% at 0210:45, quickly followed by TOGA after 0210:51 (at second stall warnings sequence).

At AP disconnection (0210:05), she started wings level and she rolled to the right at 4° per second, before first PF imputs two seconds later.

Last edited by takata; 1st Aug 2011 at 03:07.
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