UStik,

that is one heck of a picture! Not only do we have Hanno and the Dalo at the 1980 TOC in the foreground but, I'd say that is Hoppe's CAP 21 in the background! Unless, since we can't see the wing, it is Bonetti's or Tracy's CAP 20 (same fuse/elliptical wing).

I compared some other Eppler airfoils to the Dalo wing and found the E472 to be the closest match. Actually, at ~12% it is still too thick compared to the airfoil chosen by Obi. Fluid dynamics aside, hopefully, this will translate into an airfoil that will fly the 72" TOC model favourably as well as the much smaller 48" version. The proof is in the pudding I suppose.

Actually Obi, coincidentally, published a first pass at his Dalo in MAN June 1982 - exactly the same issue of MA for the CAP-21 - nice! In that case, his model was a 40 size 54" span and all indication in the review was that the model flew very well. I hope that trimming 6" off the span on an improved design won't change that!

Well, I guess it's time to put a few more lines to paper...

David.