Originally Posted by
HighPlains
Thanks for the photos. I would say that you have already exceeded my expectations with your designs. Either you have a great engineering program or someone has done the research on induced drag. It would be very interesting to put a racing engine into your designs instead of a mildly timed sport engine. You could easily touch 200mph with a Q40 engine or FAI engine, though I would stick with the Q40 engines (Jett or Nelson) because they are much easier to operate and APC makes carbon props that work well.
If you have good bearings, it is nearly impossible to blow up a .40 sized engine. Most of the top racing classes operate in the 25 to 30K+ range in the air, and the internal construction is not that much different from any of the sport engines. The mild sport engine timing will limit them to under 20K, but you want any engine to operate at it's peak power rpm in the air, so prop selection is key especially with flight profiles you are running.
We do have a great engineering program!
The reason we started this contest was that OSU had won the AIAA Design, Build, Fly contest 6 out of 7 years. They were beating 50-80 schools from all over the world. The basis for that contest was building the lightest electric planes you could to carry the prescribed payload. The way things worked out, teams were forced to build ultralight stick built film covered planes. We wanted to allow our students more material options using composites. Speedfest was born. The other reason for a speed based contest is that as you can imagine we have a lot of wind here in Oklahoma. Flying a plane with a 40mph cruising speed in 30-35mph winds does not work well. flying a 150mph plane in 30mph winds is not big deal as we have proven the last couple years.
Keep in mind, very few of the students have previous rc experience. Virtually none with glow engines. We did have fear of it becoming an engine tuning contest and that was one of the reasons behind the rpm limit. After running these engines for a season now I think we are comfortable raising the rpm limit some.
Thanks for the kind words and input. HighPlains, you are not that far away. You should come down and check it out.
Dan