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Old 31st May 2011, 03:02
  #832 (permalink)  
CONF iture
 
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29% CG

Originally Posted by takata
I'm not sure if the MAC noted 29% in the note is not a typo for "around 39%". When looking at the "target CG" as it should be computed by the fuel-computer (FCMC) for a 205 tonnes ground weight aircraft, it will give a MAC around 37.75% (target). Hence, it should vary in this part of the flight between 37.25% and 37.75% (while maximum certified AFT should be above 39.75% with a 2% safe margin).
To me, 29% makes more sense than the 37% as initially estimated by the BEA in their interim report #1
Due to the heavy cargo load, it is probable that the fwd cargo hold was also fully loaded, which explain the fwd CG of 23% at take off. Considering the initial fuel distribution, the trim tank had normally 2400kg at take off time.
During the climb, an additional 2400kg was transfered to the tail for a total of 4800kg which was still there at the time of the event.

The 37% target is an ideal that can be reached only if the initial loading would allow it.

The CG was pretty much centered, at least it was not especially aft.
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