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Old 10th May 2013, 09:28
  #16 (permalink)  
henra
 
Join Date: May 2010
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Originally Posted by john_tullamarine
A problem here is the tendency to want to make things black and white when the real world is many shades of grey.

A few thoughts ..

When we refer to a stalling angle of around 16deg, that is appropriate for an older, traditional aerofoil profile and is the typical dumbed down story for new pilots.
Exactly.

Knowldege of the different AoA at which Clmax occurs depending on the exact profile chosen is even quite old for that matter. The good old NACA Report 460 dating back to the thirties shows nicely how different the chrarcteristic of Cl can be around clmax and at what a wide range of AoA this Clmax can occur.
And those are all only old NACA 4 digit profiles.
http://naca.central.cranfield.ac.uk/...report-460.pdf

And it doesn't include Leading Edge devices or other geometrical properties of a real world wing which can enourmously change Alpha(Clmax).
So even for a theoretical infinite wing in a wind tunnel a statement that a wing stalls at 16° AoA is nonsense.
It might be helpful as a rule of thumb but in reality even that is not worth much.
If the Buffeting starts, it might be wise to stop pulling, even if your AoA gauge only shows 14°.
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