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Old 9th Aug 2012, 21:55
  #699 (permalink)  
DozyWannabe
 
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Originally Posted by ap08
Are there real-life examples of the contrary: situations when the plane suffered malfunctions and reverted to the alternate law, and in that condition successfully brought back to a runway in one piece?
Over thirty of them relating to this specific UAS problem alone!

Originally Posted by Lyman
Are we sure that it required actual input or was the airframe paid out with elevator only, and that the Nose would come down on her own without the renewed action of THS movement?
The THS movement was as fast as it was because of continued input after the apogee - As far as I understand, neutralising the stick at apogee would have meant a slower movement, and a positive level-off at apogee would have stopped movement dead at the current position.

In reference to system behaviour only (to avoid argument), the sim experience indicated that it took 6-8 seconds to roll the THS back to neutral with full forward stick applied, and with full forward stick the trim wheel very rapidly responded to the command (at most 1 second or two).

Judging by the DFDR traces even with full-NU THS, the nose did drop when it became slow enough - the problem was because of the THS and elevator position, it came straight back up again as soon as there was enough speed to do so. I don't buy the idea of autotrim in isolation making a recovery harder, because it was only doing what was asked of it. With the correct inputs it would have been a significant help.

Earlier on, how did she get to +1.65 G, whilst in load factor 1G?
The system allows up to 2.5G in Normal Law when manoeuvering. 1G is not a hard and fast limit, it's just part of the state the system tries to maintain when there's no input requesting differently.

Last edited by DozyWannabe; 9th Aug 2012 at 22:23.
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