Cul de canard and popular with anglers and trout alike. The use of CDC's in fly fishing originated from the Jura Mountains during the 1920s where fly fishermen used this feather in dry flies to aid buoyancy in a particular pattern called Moustique. It took until the 1980s for popular use of this feather within a whole range of patterns. Cul de canard Cul de canard (CDC) (French for "duck bottom") are the feathers from the back of a duck directly around the preen gland (uropygial gland); they are very buoyant due to preen oil produced by the preen gland. They are used
Canard (aeronautics) than otherwise necessary, reducing or even reversing the reduction in size enabled by the canard lift. With a lifting-canard type, the main wing must be located further aft of the center of gravity than a conventional wing, and this increases the downward pitching moment caused by the deflection of trailing-edge flaps. Highly loaded canards do not have sufficient extra lift available to balance this moment, so lifting-canard aircraft cannot readily be designed with powerful trailing-edge flaps. Pitch control in a canard type may be achieved either by the canard surface, as on the control-canard or in the same way as