Original Posted By: "Oscar Zuniga"
Chris wrote:>The problem begins when we must have airfoil data to determine the>chordwise load distribution at various angles of attack.>As Bernard Pietenpol designed the airfoil by trial and error, a>wind tunnel determined set of data has never been made available>We need plots of Coefficients of Lift, Drag, pitching moments, etcWell... by BHP's own admission, his airfoil ended up looking remarkably like the Eiffel. I believe there is data on that one (or a family), and that would probably be in the ballpark for our purposes.When the AS50xx series of airfoils were being developed for the KR, we hooked up with some folks at the UIUC to get our models tested in their wind tunnel. The graduate student who ran the analysis is an EAAer (now a PhD), and the work was part of his doctoral dissertation. Anyway, there might be a possibility of getting models of the Pietenpol airfoil into the wind tunnel, but it's a lot of work to make wing models of the required quality and specification. I'd bet there might even be historical interest in doing this, given the popularity of the design and its longevity. Maybe even a sponsor? Not suggesting we go there, just saying that it can be done if there is enough interest. But I would start by using the Eiffel plots and wouldn't feel too bad about it.Just finished a big plate of pecan pancakes. I'm over gross this morning, but it sure was good ;o)Oscar ZunigaMedford, Oregonmailto: taildrags(at)hotmail.comwebsite at http://www.flysquirrel.net________________________________________________________________________________