Then why is canard also called lift layout?
Due to the favorable interference between the front wing and the main wing, the vortex lift of the aircraft with tightly coupled canard layout increases. But the difficulty of balance still exists. For aircraft with simple structure, canard layout can provide positive lift through canard, which is beneficial to improve low-speed characteristics; However, for an aircraft equipped with a perfect high-lift device, the balance ability of canard can not be compared with the normal layout.
For the canard layout, we can see two aerodynamic surfaces, the front wing and the main wing, which "hold up" the center of gravity-aircraft flight; The normal layout is that the main wing "picks" the center of gravity in front and the tail balance force is behind. Duck layout should be more favorable than both. However, the balance of canard layout is a laborious lever, and the interference of canard layout on wing and vertical tail is very complicated. Corresponding to the normal layout, the airflow reaches the fuselage after contributing through the horizontal tail, which is generally considered to have no effect on the fuselage. Therefore, most designers prefer to avoid the trouble of duck layout and choose the normal layout with the pitch control surface at the back.
So it is called lifting layout.
Hope to adopt! !