The yaw damper's primary effect is on which stability parameter?

• A. Directional stability
• B. Roll stability
• C. Pitch stability
• D. Height stability

Answer: (A)

The yaw damper acts to damp motions about the vertical axis, controlling yaw. It senses yaw rate and applies rudder input to oppose that yawing motion, which reduces oscillations like Dutch roll and helps the aircraft maintain a steady heading. That makes directional stability—the ability to resist yawing motions and hold a stable direction—the primary parameter it improves. It doesn’t directly change roll stability (rotation about the longitudinal axis) or pitch stability (rotation about the lateral axis), and height stability isn’t the standard term for this context.