What is a Dutch roll in aviation?

A Dutch roll is characterized as an undesired coupled oscillation in roll and yaw. This phenomenon occurs in certain aircraft designs, particularly those with high aspect ratio wings and relatively small vertical stabilizers. When an aircraft experiences the Dutch roll motion, it will oscillate back and forth in a manner that combines both rolling (side-to-side tilting) and yawing (nose moving left and right), and this oscillation can create a disruptive and uncomfortable experience for passengers and crew.

Understanding the mechanics behind the Dutch roll is important for pilots, as it requires specific control techniques and sometimes the use of flight control systems to dampen the oscillations and restore smooth flight. Unlike other flight maneuvers, the Dutch roll is not a desired or controlled action; it is typically an indication of instability in yaw and roll coordination that needs to be managed.