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Old 19th Jan 2017, 15:20
  #1263 (permalink)  
Concours77
 
Join Date: Nov 2016
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@KayPam

Edifying, thank you.

"As for the Airbus stall warning.... AOA is considered invalid under 60kt (CAS invalid under 30kt, the ADR do not even try to compute it), and the stall warning was based on an AOA higher than a treshold. So invalidity of the AOA would make the stall warning stop.
According to one of our teachers in engineering school, that behavior is illegal. I hope that Airbus management decided to solve this ****slight**** problem"

This aircraft was never flying at (velocity) sixty knots save for a few seconds of ballistic flight at the top of the arc. Loss of computed (indicated) airspeed then merged into computed but (erroneous) and air speeds remained unreliable the whole four minutes to impact, imo.

The intermittent StallWarn may have begun at the loss of Computed Airdata when the aircraft quit A/P.....and this resulted from ".....WindShear...." (ACARS).

It is not possible for mass to demonstrate a vertical velocity of (17,000fpm) and have an accurate and reported AirSpeed of sixty knots....

So the StallWarn, to a savvy crew, would be rejected in any data driven solution to recovery, imo.....at the outset.

The reported "< sixty knot" trigger for (inhibited) StallWarn, if true, shows a shortsightedness at the programming level. It also suggests a blunder that may have been repeated in other ways with AutoTrim.

The THS, in its travel to the Max NU stop shows a "programmatic" impetus, not pilot induced, or even "noticed" by flight crew.

In any case, it is Auto, so there is no argument. My guess is the aircraft FCM was looking for (aircraft commanded) NU authority to meet load (computed) requirements of the airframe, independent of crew input.

45989 comment? Also, reference to Escape(CFIT) Normal Law, does StallWarn activate, even though the aircraft cannot Stall if the computed AoA is valid?

@KayPam: Re: Corsair/Beech sending PM
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