If the CG is moved forward relative to the center of lift, how does stability typically change?

• A. Stability increases
• B. Stability decreases
• C. Stability remains unchanged
• D. The aircraft cannot fly

Answer: (A)

Moving the CG forward relative to where the wing’s lift acts makes the aircraft more statically stable in pitch. With the weight ahead of the lift force, a nose-up disturbance creates a stronger nose-down pitching moment due to gravity, which tends to return the airplane to its trimmed attitude. In other words, the forward CG provides a restoring moment that resists pitching up, increasing stability.

Keep in mind that too far forward a CG can reduce elevator effectiveness for maneuvers and rotation, but within normal limits, a forward shift typically enhances longitudinal stability.