Inspaired by an Air Core a friend of ours was training on, 5 years ago a frind and I folded some coroplast over a yard stick and made a wing that flew. Neither one of us have any background or indepth knowledge of aerdonynamics other than basic theroy of flight. We went through a triangle facet wing (sucked), then a triple facet wing (very successful) and then on to stressing the coroplast in an airfoil shape over the spar. There were days we would go to the field with one airplane and a pile of wings to try on it That was five years and maybe 500 or 600 airplanes (between us) ago. Everything trial and error and TLAR. In an attempt to make a good flat bottomed trainer wing, we clamped the LE and trailing edge flat on the table while the upper wing was stressed over the spar. When the glue was set and the pressure reliesed, the leading edge rises slightly and the lower trailing edge area undercambers naturally. To our suprise, we came up with a wing that blows everything I ever flew in the balsa world away for maneuverability, slow flight... and inverted performance I never though a wing like this could have.

In the last 5 years, and most recently lurking on this forum, one thing I've heard and read is that sharp leading edged cause pitch sensitivity, higher stall speeds, and generally suck. I've seen guys get into coroplast building and go to great lengths to get more rounded leading edges...before even trying our wing. We had doubters at the field amazed at the performance once they see it fly. I never new enough to know it wasn't supposed to work, but what I do know is that I've never flown a sweeter airfoil. Solid as a rock with the CG at the spar. No pitch sensitivity whatsoever, or the pitch "hunt" I've been told it should have. The plane slows down better than my Goldberg Sr. Falcon ever dreamed of doing and It just plane won't stall unless a walking speed bobble counts before mushing back into stable forward flight. I've also been told it would lack any inverted performance...but it's fun to proove naysayers wrong...as it's just as stable and doesn't care weather is inverted or not. Snap rolls are totally lazy, and I have yet to get this plane into any type of tight spin at all.

...ok...the reason for this post:
I don't know what we did right (or wrong), but this wing with a leading edge as sharp as it could be is the best flying airfoil I've ever flown with none of the traits I've read or heard it should have. It would be interesting to hear why from an educated perspective.

I've flown Balsa planes for 20 years, and plastic planes for the last 5 years...and to date, the best flying airplane I've ever had is nothing more than a discarded gas station sign folded over a yardstick, rubberbanded to a couple aluminum rails. Less than 3 hours work, but the look at the field is priceless