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Old 17th Aug 2012, 18:05
  #1387 (permalink)  
DozyWannabe
 
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Originally Posted by infrequentflyer789
Have to agree. Not only did AB countenance it, but they built the normal law protections to counter exactly that possibility.
That was in fact a side-effect of the intent. The reason the hard protections are primarily there is to allow the pilot to make control inputs at the limit of travel without getting into difficulty.

The fundamental aspect of manual control as it applies to the FBW Airbus flight deck is that the pilot makes inputs, observes behaviour and then corrects if necessary. Slamming the stick against the backstop and holding it there runs counter to this methodology no matter what law you're in.

Now - first rule of Alternate is that there are no hard protections. If the AF447 PF had heard the PNF's call of "Alternate Law" he had no business making inputs that aggressively.

Originally Posted by CONF iture
Who's talking about C* ?
DIRECT LAW all the way since data are diagnotized as unreliable.
Why keep trying to patch on dubious data ?
Except that Direct Law throws the crew into a situation where the aircraft handles differently in *every axis* compared to what they are used to, which would likely be more risky than the current design.

In this case, what you're glossing over is that while autotrim in Alternate Law may have extended the duration of the stall if the correct recovery action had been taken, the fact is that autotrim will *help you recover* from stall by the simple action of pushing the sidestick forward and holding it there.

You're also avoiding the fact that holding the stick back like that at cruise is a thoroughly inappropriate response no matter what you're flying.

Last edited by DozyWannabe; 17th Aug 2012 at 18:10.
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