That sounds like something is seriously wrong. CFRP has less than half the density of alu and cutting a few corners, roughly the same strength. It is way stiffer though, so since most aerospace structures are buckling-constrained, NOT stress constrained, carbon will end up much lighter. Practical factors, like joint design lower this a bit, but I think I can design any GA-sized alu plane at an equivalent weight for glass fiber and considerably lighter in carbon. For most airframes that'd be half the weight in carbon. But with your application it gets worse. Flutter is a bloody complex subject and you're well into flutter-territory. Flutter is roughly driven by speed, airframe geometry, part weights and CG and airframe stiffness. Now we have CFRP that's twice as stiff and half the weight. So, the conclusion about that material comparison worries me, because it indicates underlying issues. A further positive point; such a scale F16 might be heaps easier to manufacture in composites. It will also save you lots of time engineering (because the structure is so much stiffer, most vibrations modes won't have to be checked). Notably full-scale foam molds, temporarily covered in Stretchelon or similar are a great way to make cost-effective molds for a single airframe. With respect, unless a full modal analysis is done, that incorporates the non-linearities (like the LERX effects and the agressively swept stabilators), I don't think you've seen more than a fraction of the engineering that has to take place before any sane test pilot would take it up for a test flight. I agree with remarks about the market. As long as you're building it for yourself and can cover the cost, that's fine. You might get a small part of your cost and time back in selling a few, but I think the realistic market is tiny to non-existent. Last remark, is there something (Questair Venture, Extra 500) that has a landing gear you could take over? Huge time saver and will be a considerable part of the cost.