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Old 9th May 2011, 19:54
  #1023 (permalink)  
tubby linton
 
Join Date: Mar 2007
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Retired F4 - The 330 has a big wing and two powerful engines. Cruise power settings are modest in comparison to other types such as the 320
Imagine the folowing scenario- pitots ice up generating an overspeed. The aircraft pitches up and the athr retards the power to idle,add in a powerful upcurrent as a cb is penetrated adding to the pitch up. The aircraft has a lot of energy and due to the big wing a lot of manouvrability at altitude Whilst the crew is reacting to the autopilot dropping out and the aircraft fbw law degrading the aircraft stalls. If the aircraft has been cruising at 15-20kt above VLS and assuming a rapid decelleration the crew may have had only ten seconds or less to counter the stall but having penetrated a cb they are still in an updraft. The aircraft continues to climb. The crew pitch down to counteract the stall but the speedtape is still showing an overspeed. VLS is now overlaying the Barbers pole and the crew struggle to interpret what what has happened.Their computerised FBW protected aircraft had turned against them.
The cockpit is full of warning chimes and the ecam is full of failure messages due to the icing up of the ADR. The aircraft exits the CB core and is still in a
stalled condition but now is in the downdraft of the CB and it rapidly descends towards the sea and to their demise
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