What type of stability is considered when an aircraft returns to its original position after a disturbance?

Positive stability refers to the ability of an aircraft to return to its original equilibrium position after being disturbed. When an aircraft is positively stable, any deviation from its equilibrium—such as a change in pitch from turbulence—will result in aerodynamic forces that naturally act to restore the aircraft to its initial position. For example, if an aircraft pitches up slightly, the resulting aerodynamic forces will work to bring the nose back down to its original attitude, demonstrating a characteristic of positive stability.

In contrast, neutral stability would mean that after a disturbance, the aircraft maintains its new position without returning to the original state, while negative stability indicates a tendency for the aircraft to continue moving away from its original position after a disturbance. Dynamic stability, on the other hand, refers to how an aircraft responds over time to a disturbance, considering both the initial response and subsequent oscillations; it involves both positive/negative static stability and the response characteristics of the system. Understanding these concepts is vital for pilots and flight instructors when assessing aircraft behavior and ensuring safe flying practices.