Hi, Lovely idea!
Just remember that the props have to be handed, with the tips outside the wing going downward, to get neutral handling left and right! That the props counteracts the wingtip vortices is true, their efficiency is low. The Flapjack prototype had three-blade props, the never flown fighter derivative had four-blade, if I'm remember correctly! The main point is to keep the entire span in the prop flow, so I would consider helicopter rotors :-)! And as always with flying wings remember to keep the Centre of Gravity far forward as the propellers have a huge destabilizing effect. A safe bet is 10-15% of mean chord, as just flying a disc-like glider can be problematical with so small fins! I would go safe and first build a glider that you by trial and error eventually can prove works, then scale that up till a motorized version has a similar wing loading. Remember that a twin-400-powered Zagi with a span of 48" is a handful to handle - you contraption is far smaller! The orginal was famous for its low speed flying characteristics and to be safe I am convinced you version has to have a low wingloading. My guess is using two geared 400s, 8x2400 NIMH cells and a 48-52" span! And build it light and use a symmetrical airfoil, so that trim issues are kept to the minimum! When you get it right I am sure it will fly splendidly! Folding props are almost necessary, as landning it the conventional way will be very tricky! Yours, Tord RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED] Please note that subscribe and unsubscribe messages must be sent in text only format with MIME turned off. Email sent from web based email such as Hotmail and AOL are generally NOT in text format
