PPRuNe Forums - View Single Post - AF 447 Thread no. 4
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Old 28th Jun 2011, 14:57
  #485 (permalink)  
grity
 
Join Date: Oct 2009
Location: berlin
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BOAC - I am aware of all that, but it does NOT explain why the a/c was pitched by the system towards alpha max from level cruising flight - that is the explanation I am seeking. I can see absolutely no logic in this function.

Can anyone?
"AAIB Bulletin No: 6/2001: Consequently, in turbulence the speed scale will probably be oscillating, the aircraft pitch angle could also be oscillating..."

if the bird flow for sume time nearly in a balistic curve, the AoA vane is in a stable normal position... no AoA protection will start working

AoA protection alone seems not very good for stable flight

the climb-input is interesting, after the stopp of the autopilot they moved the elevator up to +4 for ten sec. but in the following seconds the G falls to 0.5 and the pitch drops a little down (!) IMO this needs good downwind. then they hold the elevator between 0 and -3 and pushed the 4 engines this must be the climb-input, mayby together with the autotrim

ar you shure AoA reached alpha max? nighter the trim nor the AoA is shown in the diagram. the climb after the startinput could also happen with a lower AoA....
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