Dutch Roll

A coupled lateral-directional oscillation in which the aircraft alternately yaws and rolls from side to side, with the nose tracing a figure-eight or elliptical pattern on the horizon. It is caused by an imbalance between directional (yaw) stability and lateral (roll) stability, where the aircraft has relatively strong dihedral effect but weak yaw damping. Dutch roll is most relevant to swept-wing jet aircraft but can occur in any airplane. In light training aircraft, it is typically mild and dampens on its own. In larger aircraft, yaw dampers are installed to suppress it. Understanding Dutch roll demonstrates knowledge of lateral-directional stability concepts.