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Thread: Stalling CP
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Old 3rd Feb 2005, 09:23
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error_401
 
Join Date: Nov 2002
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Sorry for the late addition.


Miserlou,

Try the link at the bottom for a pretty good explanation of lift. (I doubt that Bernoulli is so important - he surely helps saving fuel but lift? - Consider flying upside down when the camber and Bernoulli now work towards the earth surface. But even with planes using normal cambered wings the AoA is not that much in inverted flight as it should be when assuming two thirds come from Bernoulli (which would imply that the AoA in inverted flight must be at least 2 times greater)...

... Yes, I am a skeptic about that Bernoulli thing.


Mad(Flt)Scientist,

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Now, my wing truly stalls and generates ZERO lift...
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I hope that no wing will generate ZERO lift at the max CL AoA when it stalls. I've learned from aerodynamics that at an AoA higher than max lift (stall AoA) there is a pronounced drop in lift but not to zero. I've been told that increasing the AoA further you may find that lift drops first, then rounds out and starts to increase again. (This being the reason for some fighter jets to be able to slowly decrease forward speed to nearly zero, at the same time increase AoA and then accelerate straight up - provided enough thrust is available - looks pretty cool)

If the wing would produce zero lift (force perpendicular to the wing chord) it would at the stall AoA simply drop the nose or get uncontrollable Divide by ZERO - ERROR - Infinity

This may help to get a better explanation, as the lift is really only ZERO either at the zero lift AoA (which usually would be something negative) or when climbing in a straight vector upwards, or diving in a straight vector downwards

So I suggest that the movement of the CP may be rearwards first, then slowly forward again, once passed the stall AoA.
How about the CP moving further than the CG. Sounds like much fun.

Do you know if the CP can move outside the surface of the airfoil producing the lift? Never got that one answered.


Some idea may be found here
http://www.allstar.fiu.edu/aero/FlightTheory.htm
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