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Old 22nd Jul 2011, 04:34
  #2123 (permalink)  
Machinbird
 
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The conditions described above, due to the "any" in the first sentence, are assumed to be "mutually exclusive" and any one or a combination will trigger ABNORMAL ATTITUDE LAW.

Not so, and the FCOM has unintentionally lead everyone astray.

Due to the discrepancy in the airspeed measurement, all three ADRs were rejected by the FCC, which left either of the inertial input criteria:-

— Pitch attitude > 50° nose up or 30° nose down
— Bank angle > 125°

to be met. This didn't happen.
Now imagine you are pushing the nose down to recover the aircraft from the stall, and airspeeds becomes valid, and you get to 30 degrees nose low, and abnormal attitude law wakes up!
Might not that interfere with continued trimming nose down automatically and the recovery?

Better to crank the trim down manually to avoid any uncertainty, I think.
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