The rudder primarily causes rotation about which axis?

• A. Longitudinal
• B. Yaw
• C. Pitch
• D. Roll

Answer: (B)

Rudder control mainly produces yaw, which is rotation about the vertical axis. When the rudder is deflected, the airflow pushes the tail to one side, creating a turning moment that makes the nose point left or right. This is different from roll (rotation around the front-to-back, or longitudinal, axis) and pitch (rotation around the side-to-side, or lateral, axis). Roll is managed by the ailerons, and pitch by the elevator, while the rudder specifically governs directional changes about the vertical axis.