Positive dynamic stability results in a response that is…

• A. Damped
• B. Not damped
• C. Oscillatory with growing amplitude
• D. Immediate return to straight-and-level flight

Answer: (A)

Positive dynamic stability means that after a disturbance, the airplane’s motion tends to settle back toward straight-and-level flight, with any oscillations dying out over time. The aerodynamic forces provide restoring moments that oppose the departure and progressively reduce the motion, so the response is damped. If there’s no damping, the oscillations would continue at the same amplitude (neutral stability); if the oscillations grow, the aircraft would become increasingly unstable; an immediate return implies no residual motion, which isn’t the typical dynamic response after a disturbance.