Aero Overview Aerodynamically speaking, canard aircraft are more difficult to design than conventional aircraft.  The wing and canard operate as a matched set and their synergy affects performance and safety to a much greater degree than conventional designs.  The wing and canard must be carefully configured to obtain the desired neutral point, stall behavior, CG range, stability margins, etc.  Theory and behavior of canards are not well documented in aerodynamic texts.  Even worse, there are subtle and counterintuitive “rules” that must be followed to design a safe and efficient canard aircraft. The above paragraph explains why today's plans-built canards use the same wing, canard and airfoils that Burt Rutan designed for the Long-EZ in the late 1970's.  Some derivative aircraft reinforce the wing and canard structure for higher gross weights, but their aerodynamic specifications pretty much duplicate the Long-EZ.  And that’s the direction I was headed, except I planned to emulate the slightly larger Cozy IV wing.  But reality checks forced me to change course. There were two problems with my plan: • A primary goal for the Apollo was to lower the takeoff and landing speeds.  Duplicating the Cozy wing wasn’t going to achieve that objective. • The Apollo’s fuselage is 3” wider and 5” taller than the Cozy IV, and Airplane PDQ was predicting its maximum speed was 8 knots  slower than the Cozy.  I considered that to be an unacceptable trade-off. After investigating options like adding wing area, flaps, vortex generators, pneumatic turbulators and the like, it was evident that modifications to the basic Cozy wing were not sufficient.  The only way to resolve both issues was to design a new wing and to use new airfoils.  This epiphany doubled the amount of design work that had to be done! The rest of this story is covered in the sections described below.  Use the Aerodynamics drop-down menu to read about the following: Site Map Email the Designer Copyright © 2012 Apollo Canard