Canard, like so many words in the English language, is of French origin and means duck. The canard type paper airplane, like the duck, appears to have its wings at the tail end of its body and there are many advantages and very few disadvantages to this type of design.
On conventionally configured airplanes, the CL of the wing is slightly aft of the CG. Because the CG is ahead of the lift, the aircraft will nose over and dive without a slight down thrust on the tail and results in a certain amount of drag for the main wing. In effect, the down thrust on the tail can be thought of as extra weight the wing has to carry, or as more induced drag. By moving the wing to the tail of the airplane, which produces a nose-heavy condition … and by introducing a separate smaller wing at the nose creating lift, you can now increase the efficiency of the airplane by decreasing the induced drag. In other words, you reduce the wing loading of the main wing. Any reduction in drag results in increased efficiency. Sketch 5-1 illustrates the lift forces and the CG on a typical canard. Note the location of the CG.
The canard design is extremely stable, as the main lifting force of the paper airplane of the main wing, and the drag it produces, is behind the center of gravity. It thereby enhances stability much like the feathers on a badminton shuttlecock. An added benefit is that the front wing or fore plane has a higher angle of incidence than the main wing. When the AOA is increased as the airplane approaches the stall, the fore plane, due to its higher AOA and higher wing loading, stalls before the main wing. The fore plane then loses lift, lowering the nose, reducing the AOA on the main wing, and eliminating any possibility of the main wing stalling. Due to this natural stability, the canard’s vertical fins can be smaller. For our purposes, this tends to balance better and as a result, fewer paper clips are required to achieve a proper CG, thus reducing weight and enhancing all around performance.
A major difference between conventionally configured and canard type paper airplanes, is that of pitch trim. The fore plane generates lift instead of down thrust, just the opposite as a tail would in a conventionally configured or delta airplane. A canard should have its trim tabs bent down similar to a wing flap, to generate lift for nose-up trim, and vice versa for nose-down trim.
Another way to improve performance with the canard is to build in a slight amount of anhedral (negative dihedral) on the fore plane. To do this, simply fold the entire front wing down from the center fold. This ensures that the main wing doesn’t ride in the same disturbed airflow as the fore plane.