Thank you Paul,

I have tried a modification of the Schuemann tip from gliders on a Quickie. I built the wing is straight for 75% of the span, then angled back about 10 degrees on the leading and trailing edge. The theory is that air that hits the leading edge together tends to stay together, and so with the tips angled back slightly, this effect helps hold the air on the rest of the wing in place, limiting span flow. A secondary effect is that the center of lift is moved back slightly on the tip so that in the turn the wing tends to wash out the tips as the angle of attack is increased. This should help achieve a elliptical distribution of lift for a small wingtip votex.

This is a lot on this subject and general drag reduction in the Pylon string, Quickie 500, Shorter fuselage and future of composites.

Bob