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Old 18th Jun 2011, 16:16
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Machinbird
 
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by Rudderrat

"The maximum elevator deflection is 30° nose up, and 17° nose down. The maximum THS deflection is 13.5° nose up, and 4° nose down."

I agree with RetiredF4. If the side stick had been held fully forward, the stab trim could have changed the THS's angle of attack by about 17.5 degs. Unfortunately, all that would have achieved would have been to INCREASE its angle of attack. The Stab is permanently stalled in their situation.
As others have mentioned, what matters is the NET pitching moment. If there is enough pitching moment nose down, rotation nose down will occur.
There is Lift and Drag after stall. Lift does not suddenly dissapear post stall but follows a variable path toward zero lift at ~ 90 degrees angle of attack (and becomes 100% drag there)
The path depends on:

Angle of attack-The Primary variable
Aspect Ratio,
Airfoil thickness ratio,
Reynolds Number that the wing is operating at.

Take some time to understand the following document regarding post stall aerodynamics.
http://home.comcast.net/~shademaker/...tStall44XX.pdf

Last edited by Machinbird; 18th Jun 2011 at 16:46. Reason: Correcting statement to the first lift coefficient zero point, not the second.
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