PPRuNe Forums - View Single Post - AF 447 Thread No. 10
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Old 8th November 2012 | 18:03
  #727 (permalink)  
mm43
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Joined: Jun 2009
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From: NNW of Antipodes
The previous few posts have highlighted IMO the single minded focus the PF had in over-controlling the roll (PIO) at the expense of paying any attention to pitch attitude, vertical speed or altitude. At the back of his mind was his initial introduction to all the good things associated with Airbus FBW, i.e.

In Normal Law it is a protected aircraft with three thresholds incorporated in the protection:
  • Alpha Prot(ection), which is the maximum attainable stick-free AOA. The auto-trim stops there because there is no valid reason to fly at such a low speed for a lengthy period of time; the speed brakes, if extended, retract automatically.
  • Alpha floor, which is the AOA where engine thrust increases to TOGA even with auto-thrust selected off.
  • Alpha max, which is the maximum attainable AOA with the side stick held fully back.
It took 18 odd seconds for the PNF to announce (I suspect rather quietly), "ALT LAW, protections lost". During that time the PF had just assumed that provided he kept the SS back, the longitudinal stuff would look after itself. It didn't, and with less than 50 seconds of the flight remaining, his hallelujah announcement, "But I’ve been at maxi nose-up for a while", kind of says it all.

None of the above excuses the lack of CRM or lack of reference to the QRH, when it was patently obvious that they knew they "had lost the speeds".

Last edited by mm43; 8th November 2012 at 18:04.
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