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Old 26th Aug 2012, 13:28
  #124 (permalink)  
CONF iture
 
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Originally Posted by HN39
Considering the inertia of the airplane, I'm not so sure of that. Perhaps you should try it in your next simulator opportunity.
Every rotation is done in direct law, and any undesirable erratic movement would be immediately evident due the instantaneous response of the aircraft.

I suppose you mean that there is no autotrim and that you assume that the PF would not have trimmed manually. At 02:11:35 he seemed pretty desperate to keep the nose up, and in direct law "USE MAN PITCH TRIM" is displayed on the PFD.
Did he try to trim up to the FULL stop of 14 degrees ... ?
If the pilot wanted to trim up, let him make such a silly thing himself, Please. We really don’t need any automation to do it for him.
If the guy had done it himself, I would not show up here to defend his action.

In the two instances that the PF released the stick, the elevator responded and the airplane promptly pitched ND.
And nothing to compare with what would have been obtain in direct law in terms of ND movement and AoA reducing in order to achieve stall exit.

While it is probable that the stall warning would have been uninterrupted in direct law, that is not certain.
If you think you can get below 60 knots on elevators only, it is your call. What I want to see is the BEA calling the shot. That should be detailed already.

I have earlier expressed my opinion on the visibility of the sidestick. Seeing the control pulled to the back stop might have added another clue that might have pointed the PNF and particularly the captain towards a correct diagnosis of the situation.
So we agree.
It was the duty of the BEA to make recommendations to Airbus to include in their documentation how the sidestick concept does not permit the same type of supervision allowed by more conventional flight control commands.

The crews operating the Airbus must be made aware of such characteristic.

Perhaps you would care to justify that opinion considering that BEA's investigations "are conducted with the sole objective of improving aviation safety and are not intended to apportion blame or liability."
That's something we can keep for later, but for now I could resume it that way : Do not write too much in the technical as the judiciary could be too well at ease to use it afterwards …
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