Okay, thanks guys. I was not aware of the 25% standard, although I did know there were isues with pitch moments. I am familiar with the flat plate airfoil, and I'd be happy with it too, but of course it won't provide the solution I seek. I also used to do that thing you do with the yardstick, at the time I didn't know why. Do now.

I had a feeling this wasn't possible, but you never know. Even if we could find a suitable airfoil, designing a stable plane around it would be a challenge. So, I think this is a non-starter.

Thanks for your input. Brainstorms still welcome!

Cheers from the Barfly.