My first post, I don't have a Mooney but I've been thinking about getting one, so I've been reading this forum for a while, but this topic is something along the lines of what I do. I develop PMA parts (but usually for part 25 aircraft), I write certification reports and develop PMA/STCs, and I'm a DAR, and I've worked projects involving composites. Although not exactly easy, I don't think this project would be all that hard if you kept the design very similar to original parts, with only minor changes. Digitally scan a 201 cowling to create a model, make the changes you want, and then use the model to make the tool, which will be quite expensive. As far as material goes, don't be too wrapped up in carbon fiber, carbon fiber is not always the best material for the job when looking at all factors. In this case, I think epoxy-glass would be my choice, but I’d have to look into it more to be sure. There are many pods and cowlings mounted on much faster aircraft that are made using epoxy glass. I would think that if you could get at least ten people to pre order, with a deposit, it might be doable but not if you’re paying someone ells (DER and other consultants) to do all the certification work. What other parts would you need besides the actual cowling? What is the price of the other STCs and where does the kit price need to be to put this on a 40-50 thousand dollar airplane, how much time would it take to install, how many could be sold in five years? The answer to all these questions might make the project not look so good. As far as getting someone else’s STC, why did someone stop selling it, if it was a good seller? It's all about volumes, and aircraft parts rarely have good volumes.