Which type of stability tends to maintain an aircraft's state of motion?

The correct answer is positive static stability because this concept refers to an aircraft's tendency to return to its original position after experiencing a disturbance. When a disturbance occurs, such as a change in pitch, an aircraft with positive static stability will naturally want to revert back to its initial state of motion without requiring pilot intervention. This is illustrated through observable effects, for example, an aircraft that pitches up in response to a gust of wind will have a tendency to return to its level flight attitude.

In contrast, dynamic stability involves the aircraft's response over time to a disturbance, which includes how oscillations or responses evolve. Negative static stability would indicate that any disturbance causes the aircraft to move further away from its original state, leading to an increasing divergence from the desired flight path. Neutral stability means there is no tendency to return to the original state, resulting in the aircraft remaining in the new position if disturbed.

Understanding these different types of stability is crucial for pilots, especially when adjusting their control inputs to maintain safe and stable flight. Positive static stability helps ensure that small disturbances do not result in significant changes to the aircraft's flight path, enhancing safety and comfort for the pilot and passengers.