Greg; Back around 1980 I spent a lot of time building a computer program that would analyze the stresses in a model wing, and predict how the wing would fail. At the time my wings were mostly wood with a little carbon and glass fiber, and the program did predict some failures well. But I stopped using the program because it would only analyze a few of the ways a wing could fail and the program required a lot of data entry to define the wings structure. These same problems would have to be addressed today although the computers are much better. Matt Gewain Composite Structures Technology I have looked a Joe Wurts wing lay-up spreadsheet it looks like a good way to go. I was just wondering if there is a spreadsheet for figuring out spar strength if you wanted to avoid the use of so much carbon fiber. -- Greg Nuspel RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
