I was going to ask how the ribs got broken, but re-read your original post. Thanks for the information. I had a PT-40 that was my very first build. I actually forgot to put the spar in on one wing half and realized it when I had finished glueing in the ribs. There seemed to be something missing, and of course, sitting there was this piece of hardwood that looked like it belonged in there. So, I re-read the directions and sure enough.. voila.. wing spar.

I put the whole thing aside for a while and bought a wing kit and started over again. But, later on, I worked with someone that did basically what you did to reinforce the ribs and then used a piece of 1/8 balsa between ribs to form a sort of latticework to replace the spar. It flew just fine. I've since sold it and, from what I understand, still flys.

Thanks for the posting. It will be one of those keepers. Oh, and I prefer empty Cheerios boxes