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Old 8th Aug 2012, 20:35
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jcjeant
 
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Ah, but the flight control computers are not programmed with the concept of stall and to the best of my knowledge never have been.

The stall warning parameters are encoded into the annunciator system, but the flight control computers are oblivious to stall in Alternate Law - and most would say rightly so, because for the computers to be able to override the human when in a degraded state would open the aircraft's safety to significant risk if the computers get it wrong (not to mention the fact that the backlash from the Airbus-sceptic brigade would be deafening if this were the case!).

The point is that outside of Normal Law, the systems are designed to defer to the pilot's inputs - no matter what those inputs are - for better or worse. This is based on the reasonable assumption that the human pilot will have a much better ability to adapt to circumstance than the computer ever could. In this case the crew were clearly overwhelmed and not only made mistakes, but repeated the same mistakes over and over again with tragic consequences.
I thought of everything and so I had to raise troops for mount a counter attack
In normal law (autopilot engaged or not) the automatic trim is a must and a great help in flying the aircraft (thank's also to the protections)
In alternate law .. things are not all the same
With the autopilot off (the pilot fly manually) .. alternate law says there is no more pitch protection ..
But still .. auto trim remains active
piloting in manual (pitch matter) is using the stick and the trim (the pilot is using both hands)
Not with Airbus ...
The pilot does not control the trim .. and this one continues to act as in normal law .. but then it is no longer active protection ....
To me this is a bad design .. the pilot don't control (full manual control) entirely the pitch ...
In alternate law the auto trim is not a help ... instead it's like throw a lead buoy at somebody drowning

Last edited by jcjeant; 8th Aug 2012 at 20:41.
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