Yawing

Yawing is the rotation of a vehicle about its vertical axis, producing a change in heading. The yaw angle, typically denoted psi, measures the orientation of the longitudinal axis relative to a reference direction such as true north. Yaw is one component of vehicle attitude, alongside pitch and roll, and is a key factor in maneuverability and stability.

In aviation, yaw is controlled mainly by the rudder, a movable vertical surface on the tail. Yawing movements occur during turns, crosswinds, and when thrust is asymmetric. Coordinated flight uses ailerons and elevators to produce banked turns with minimal sideslip. Adverse yaw can occur when aileron input initially produces opposite yaw. Aircraft stability and autopilots provide yaw damping to reduce oscillations and keep a steady heading.

In ships and boats, yaw is the change of heading about the vertical axis caused by rudder deflection, propulsive forces, wind, and water currents. A vessel may exhibit weather helm or lee helm depending on the balance of forces. Maintaining a desired heading involves managing yaw rate and heading error, often with a rudder feedback or autopilot.

Measurement and control: yaw rate (r) is the angular velocity about the vertical axis; yaw angle (psi) is the cumulative heading. Instruments such as the turn indicator, heading indicator, and attitude indicator help monitor yaw, and steering systems or autopilots act to regulate it.

Related topics include heading, roll, pitch, adverse yaw, slip, and weather helm.