What statement best describes the effect of improper balance on CG and control?

• A. It has no effect on stability.
• B. It improves elevator effectiveness.
• C. It reduces drag only.
• D. It moves the CG, altering stability and elevator effectiveness; improper balance can cause control difficulties.

Answer: (D)

The key idea is that where the center of gravity sits along the longitudinal axis sets how the airplane handles in pitch and how much elevator input is needed to control that pitch. If balance is off, the CG shifts away from its intended range, changing both static stability and the tail’s effectiveness in producing pitch moments. A forward CG makes the aircraft more statically stable but harder to rotate because the elevator must deflect more to raise the nose, reducing elevator effectiveness. An aft CG reduces stability and can make control more sensitive, potentially leading to control difficulties if the elevator can’t counteract moments quickly enough. So improper balance moves the CG, altering stability and elevator effectiveness and can cause control difficulties. Drag isn’t the primary outcome of CG location.