PPRuNe Forums - View Single Post - AF 447 Thread No. 8
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Old 26th Apr 2012, 18:31
  #211 (permalink)  
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Join Date: Jun 2009
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Thank you Roul and Rat.

I was not looking carefully at the yaw trace on the recorder.

@ Roul

The technique of "unloading" is maybe foreign to many of the "heavy" pilots. No problem. And my reading of the existing procedures of many airline jets at the time emphasized minimum loss of altitude. Funny, but if you get those wings producing lift quickly, you'll lose less altitude. Worry about the gee limits later when recovering from the lower pitch attitude.

That being said, pilots must realize that you are either approaching a stall or actually in one. Looks to this old dinosaur that the 'bus has excellent yaw stability ( or great dampers) and decent roll characteristics even when the wing is completely stalled. So it comes down to the continued nose up command on AF447. Didn't see drastic roll angles or yaw excursions on the traces. You can pull all you want, but all you'll get is the gee commanded position of the elevators and the THS following to help trim.

What's funny to me was that the primitive FBW system I flew actually moved the stabilizers for nose down when we got to our AoA limit, regardless of our gee command. Gee, imagine using AoA sensors regardless of CAS once weight-on-wheels flipped once airborne.

@Doze

Maybe the overspeed control was what the dude was thinking due to the unusual noise from a fully stalled wing. Dunno.
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