I was interested about the most common airfoil that is used in pattern these days...the airfoil seems to be thin with a fairly sharp leading edge and not very thick at the highest point.

And your question would be?????

John

Probably an NACA 0010 . A ten percent symmetrical. Could even be a bit less, but I would doubt it.

Hey Boss,...

Your question put me on the hunt for an article I remember reading a while back. It took me these past two days to tear my office apart before I finally found the article, ha!!

Rick Allison wrote an article in the April '94 issue of Model Builder magazine entitled !QUOT!Pattern Airfoils 101!QUOT!. In this article he had a comparative illustration of typical pattern airfoils for the day. He compared the Summit III, Jekyll, Conquest, and Cursor/Boxer airfoils. While the Summit, Conquest, and Cursor/Boxer were 13% thick, the Jekyll was 14% thick. The high point was the most furthest back on the Cursor/Boxer at 40%. Conquest high point was at 33%, Jekyll was 32% and Summit III was at 26%.

At the end of the article Mr. Allison stated that the particular airfoil that has worked best for him was a NACA Series 6 derivative with a wing root thickness of 13% and tip thickness of 9-10 percent, with the high point as far back as 40%. With the high point this far back it will give a relatively sharp leading edge radius allowing for clean and predictable "breaks" for stalls in snapping and spinning maneuvers.

Hope that answers some questions. If you are looking for plots of specific airfoils let me know I might be able to provide either an AutoCAD .dwg file or airfoil coordinates.

Sincerely,
Steve T.
Monson, Massachusetts

Steve..That does answer my question very well...thanks!!

So Eppler 169 (14%) and 168 (12%) with the thickest portion of the air foil at 26.5% and a rounder tip would have a gentler stall...correct?