The Wittman Tailwind has a constant chord wing. The wooden ribs that slip onto the main spar are made from 1/2" wide strips of wood instead of a typical 1/4" wide strips of wood so there is more gluing surface, rib to plywood. I personally would not want to glue wood skins to foam ribs unless the foam was PVC foam with a layer of glass on each side of the ribs and I am still not sure I would consider that technique. Well I might. There was a fellow here in my area that purchased a Wittman Tailwind a few years ago that someone else had started. The wings were already supposedly finished and closed. This fellow finished the airplane, it was beautiful. I think he had made more than one flight, anyway just after takeoff on his last flight one or both of his wing/s came apart and of course this guy was instantly killed. The investigation revealed that the ribs were not glued together properly or glued to the spars. I can't remember if the ribs were glued to the plywood or just tacked down. My point is be careful with someones craftsmanship that you don't know or are unable to inspect.
The Wittman Tailwind wings were originally built with wooden ribs, covered with aircraft grade plywood and then covered with the old fabric and dope technique. Now most people cover the plywood with a light layer of fiberglass and use epoxy resin as the glue and stiffener for the glass cloth. Most in the Tailwind community now use the West Epoxy System for this purpose. As most of you know West System was originally developed for the boating industry. It was developed specifically to adhere glass cloth and wood together or for wood to wood in boats. Most of us in the KR community use T88 Epoxy for gluing our wooden structures together as does many in the Tailwind community. There are some in the Tailwind community of builders who use the West System for gluing all their ribs together, gluing ribs to the spars, gluing the plywood to the ribs and for gluing the fiberglass cloth onto the outside of the plywood wing surfaces. Wooden wings are great, metal wings are great, the way we make our wings is just great as well. All of these techniques work as long as they are built properly. Larry H. ________________________________ I wonder if anyone has done a foam rib with ply skin attached directly to the foam? Would that even work? Fred Johnson Reno, NV
