Bruce, I reviewed the rules for '2003 and winglets are not prohibited...so far. I'll probably contact SAE to confirm this. If the only limitations are the wingspan, TO distance and cargo cmpt volume, then we'll have a VERY interesting competition next year!
I wonder how bad it is -- the induced drag...
My first estimates (wing Cd 0.06; fuselage, 1.2; tail, 0.1 and 'wheel' u=0.03; total mass=34 pounds ) indicate I'd need 0.36 BHP (~3.6 lbf) to get to 38mph within 200 feet! The FX.61 has theorically 1.85 BHP @ 16000rpm - at 70% efficiency, that's ~1.3 BHP available! ... Something is amiss here, don't you think?! -- An FX.61 does not get a 34-pound bird to 38 mph that easy!

I'll have to build a database with TO data from a couple of models and engines and extrapolate the data to my endeavour!!! On to the field...or the net...

Best regards. Souza.