Any thoughts on substituting S-glass yarn for the flagged UNI spar cap for a Long EZ? Pro's/con's, etc. I read a thread about substituting kevlar as skins and winglet attaching for a VEZ and got a lot of info there, mostly along the lines of, "don't substitute materials, the designer knew what they were doing." My reason for asking comes from reading the construction manual; the wing spar cap is S-glass yarn, while the canard is the flagged UNI. Second reason, I took a Sport-Air workshop, and for the canard/airfoil section we assembled in class, we used S-glass for the spar cap. Granted, this is a big deviation from the Rutan plans, but I found the S-glass easier to lay than the flagging I tried at home. So, again, my question would be yea or nay? Or, perhaps I already answered my own question...
