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) to limit drag. Such a canard airfoil has a greater airfoil camber than the wing. Another possibility is to decrease the aspect ratio of the canard, with again more lift-induced drag and possibly a higher stall angle than the wing. A design approach used by Burt Rutan is a high aspect ratio canard with higher lift coefficient (the wing loading of the canard is between 1.6 and 2 times the wing one) and a canard airfoil whose lift coefficient slope is non-linear (nearly flat) between 14° and 24°. Another stabilisation parameter is the power effect. In case of canard pusher