PPRuNe Forums - View Single Post - AF 447 Thread No. 12
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Old 28th Sep 2014, 18:50
  #466 (permalink)  
_Phoenix_
 
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The control technique used seems to be relatively unimportant in Normal Law but has critical implications in Laws that involve direct motions of control surfaces such as Alt2b.
Only the roll was in direct law. Pitch was never direct.
"When the airplane's nose was pointed up, it stayed pointed up - to maintain the same g-load and pitch rate.."
Bonin's "heavy hand" fully controlled the roll, he kept the wing at horizontal during 38000ft stalled descent, this might say something about his piloting skills, apart of imaginary PIO
Bonin held the sidestick back in that initial pull up, just long enough to pitch the airplane to 12°, we still don't know why... however it happened relatively fast and similar to AF471, see post #524.

Consider this analogy, if you want: the driver sees the traffic light turning from green to yellow, initially he brakes (pulls up), but it is not good (stall alarm goes off). The driver decides to go through the intersection, he bottom the acceleration pedal but for some reason the car's computer continue to apply brake and service brake all together (THS max NU and elevator half way NU), the engine's torque simply cannot overcome the brake applied to disks, the driver is confused "I lost all control of the car I don’t understand anything, I've tried everything"... he brakes again, the car stops in the middle of intersection, independent of any other action of the driver.
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