My personal impressions..from experience and research...... Canards are a lot like conventional planforms in most respects.....(doh!). They react in much the same way to CG shifts, and for a given CG location, turn about as well. Differences: when forced into a stall, a properly set up canard will stall the canard before the wing, drop the nose slightly, and resume flying when the stalling control input is removed. It (properly set up, remember) will not stall the wing, so will not be subject to tip stall and subsequent roll/altitude loss/recovery. That is the good news. The bad news is that without careful experimentation with cg and incidences, canard airfoils, etc, it may prove impossible to force the wing to max coeficient of lift before the canard stalls. This is what you give away in order to achieve the canard's docile stall characteristic. More bad news: The canard will require careful placing of the canard foil relative to the wing, either above, below, and/or dihedraled, to minimize downwash on the wing center section. This can cause a serious loss of effiency of the wing if not taken into account, and even if taken carefully in to account, still may result in an inefficient fuselage shape. The vertical fin, due to it's location nearer the CG, will have to be larger than a conventional planform's. The weak parts are in front. Some good news: Both surfaces are lifting, one isn't just being dragged along for no purpose except stability. The overall fuselage will be shorter. Canards react with a mild pitch up when encountering lift, both signalling it and automatically climbing a bit when lift is encountered. Bottom line (subject to debate) Probably a conventional model can be made a percent or three more efficient but the canard may be a percent or three better in handling. For the sake of argument..I'd guess Joe Wurts would be better off with a conventional planform, Joe Blow with a canard.............but whichever either is flying, I'll put my money on Wurts......... So Pick up the latest version of Martin Simmons' "Model Aircraft Aerodynamics" and have at it...that's where the real fun is anyway. Dan RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
