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Old 10-19-2013 | 08:26 AM
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Rob2160
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Originally Posted by airraptor
BLW that book ay be good but Bernoullis theory is a very small part of how a wing or a rotating wing makes lift/thrust.

Agreed, I just posted a bunch of videos in the Aerodynamics forum on this very subject..

http://www.youtube.com/watch?v=aFO4PBolwFg

Believing lift is produced only by faster moving air over the top of an airfoil would mean a wing / propeller / helicopter rotor can produce lift with no downwash / prop wash...

Try standing under a hovering helicopter.... try standing behind a real prop aircraft at full power... Propwash / downwash is VERY real and it is the reaction to this deflection of air that produces thrust / lift,

Bernoulli does factor into the equations but his theorem is often applied incorrectly in this context as the videos show.

http://www.youtube.com/watch?v=zV06PgxarW0
Last edited by Rob2160; 10-19-2013 at 08:30 AM.
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