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Thread: Theory on lift
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Old 2nd Dec 2012, 18:36
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Owain Glyndwr
 
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Lyman

You may want to make a note of the date or something, but here is a first - I am going to agree with you!

NACA measurements (wind tunnel I'm afraid FlightpathOBN) made back in 1938 show that the build up of lift as you near the ground is NOT equivalent to an effective increase in AoA as suggested by the 'mirror image' modelling, but between say 5 and 10 deg AoA at least is more or less entirely due to a steady build up of pressure underneath the wing, with the upper surface flow changing very little from its free air behaviour. NACA TM 1095 if anyone is interested.

This of course says nothing about how wake vorticity is affected, but I didn't think that was the issue being debated here?

Last edited by Owain Glyndwr; 2nd Dec 2012 at 19:04.
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