center of gravity

“All fixed wing aircraft act in flight as if their entire mass is centered at one single point. This point is called the Center of Gravity (CG). The CG is usually located about 20-30% back from the wing’s Leading Edge. As an example, if “up” elevator is applied, the entire airplane does not rise up as if it were an elevator. Instead, the tail drops and the nose points upwards as if it were a “see-saw”. The pivot point of the see-saw is the airplane’s CG. If the CG is too far to the rear, a fixed wing airplane will be too unstable and control sensitive to fly. If the CG is located too far forward, the elevator may be too weak to raise the “heavy” nose during landing.”