I am considering switching my design from aluminum to wood. (Low-wing, single seat, approx. 1,250 lb gross.) I am familiar with ANC-18 and have been studying the Falco plans and construction manual to learn what I can (thank you, Sequoia--what a gold mine!). I have a few questions for those who have experience, or at least reliable knowledge of this construction method. Weight estimation. Raymer uses the same coefficient for wood and metal in his initial W[SUB]e[/SUB]/W[SUB]0[/SUB] equation (a=1.19, see Simplified p. 20), suggesting that they are similar. Later, when dealing with weight estimation by component, he provides statistical equations for components but says they're for conventional aluminum construction. Then he suggests that a wood fuselage could weigh 60% more (!) due to minimum gauge effects, and you need to do more design/analysis to find the weight. Perhaps I'll just have to do this to complete the trade study, but do you know of any references that address weight estimation of a structure similar to a Falco or GP-4? Wing attachment. In aluminum, my design includes an overlapping sailplane-style spar (with an adaptation of Dan Weseman's Panther wing folding mechanism). I can do this with wood box spars (though probably with a weight penalty) but my main concern is that with wood movement, the spars might swell enough inside of the carry through box to bind and prevent removal. Has anyone seen this done in wood? Glues & Epoxies. I find the idea of using an epoxy adhesive appealing since it would eliminate masking off glue joints when sealing interior surfaces before assembly, but this gets us back to the whole paint color and temperature discussion just like composites. If you have experience or have done testing of wood/epoxy joints at elevated temperatures, I'm all ears. Finishing. Some plywood-skinned planes are finished with a layer of glass cloth (but no mention of this in the Falco manual). Why is this done, just to prevent spliced seams from possibly opening up over time? Perhaps to protect thin skins from hangar rash? I do not see a useful structural advantage to a glass skin on one side only, and would hesitate to include its value when sizing skins. By the time a wet layup us smoothed over the entire plane, I would imagine this is a considerable weight penalty (even 20 lb would be significant). (Edit: forgot to add this one) Laminar flow. Is it realistic to think that plywood-skinned wings can be constructed true enough to take advantage of laminar flow?