Hi Thomas!
Having designed, scratch built, flown and crashed a 22 pound model of the Pond Racer, I want to share my experience with you.
Begin with looking at this video from 2007:
http://www.rcmovie.de/video/b7db99ed...mit-Pond-Racer
It was of course a major inspiration for me…so I built my Pond Racer in conventional plywood/balsa construction with foam wings. It had a wingspan of 91 inches, was 77 inches long and was powered by two YS.91 FZ. It flew gorgeous after I found the right C.G. point and was not difficult to handle at all. One reason it flew so well was that I increased the wing chord by 20%.
I can’t fly like the young expert Gernot Bruckmann in the rcmovie but it was great fun for a retired pylon flyer. So continue with your CAD-drawn Pond Racer and enjoy the reward to take your design to the air!
Greetings,
Lars