Re: [Paddlewise] Paddle cross sections

From: Peter Treby <ptreby_at_ozemail.com.au>
Date: Thu, 06 Dec 2007 07:31:26 +1100
"Asymmetry is not required to generate lift. Try thinking of stunt  
planes that fly up-side-down. I don't know if they have asymmetrical  
foils, but they can fly wheels upward or downward because lift is a  
matter of angle of attack. "
Then try thinking of why the stunt plane does have an asymmetric foil 
wing, with an upside and a downside. When flying in the wheels down 
orientation, the foil wings are generating lift by virtue of the longer 
upper surface creating a relative vacuum. When flying upside down, the 
lift is generated only by angle of attack. I think there may be a 
difference between these, which leads me back to the symmetric cross 
section GP. I still wonder whether there is any foil type lift 
operating, as seems to be claimed sometimes.
***************************************************************************
PaddleWise Paddling Mailing List - Any opinions or suggestions expressed
here are solely those of the writer(s). You must assume the entire
responsibility for reliance upon them. All postings copyright the author.
Submissions:     PaddleWise_at_PaddleWise.net
Subscriptions:   PaddleWise-request_at_PaddleWise.net
Website:         http://www.paddlewise.net/
***************************************************************************
Received on Wed Dec 05 2007 - 12:31:42 PST

This archive was generated by hypermail 2.4.0 : Thu Aug 21 2025 - 16:31:27 PDT