I’ve read that the Sig Smith Mini biplane has a tendency to balloon upward upon application of throttle. I believe I read it on Cafeenman’s website airfieldmodels.com. I’m not going to be able to match his construction but I’ll do my best.

In my wandering on the web looking for photographs of different Smith DSA-1 aircraft I ran across Sky Classic Aircraft. They are offering new plans for the full size aircraft. They show the aircraft being built in different stages. I was astonished when I looked at photos of the wings. They were not under cambered or flat bottomed. The site also showed a 3 view and there low and behold was “Wing foil NACA 23013”, a semi symmetrical airfoil.

My question is this. Would this airfoil help eliminate the ballooning? It would be easy enough to cut new ribs. Would you do it?

Thanks,
John