Dutch roll

Dutch roll is one of an aircraft's flight dynamic modes (others include phugoid, short period, and spiral divergence). It involves a coupling of roll and yaw which is normally well damped in most light aircraft. Some aircraft with well-damped dutch roll modes can experience a degradation in damping as airspeed and altitude increase. Dutch roll stability can be artificially increased by the installation of a yaw-damper (commonly referred to incorrectly as a yaw-dampener).

Related Topics:
Dutch roll - Flight dynamic - Phugoid - Short period - Spiral divergence - Damping - Airspeed - Altitude

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The Dutch Roll mode can be excited by any use of aileron or rudder, but for flight test purposes it is usually excited with a rudder doublet or singlet. Some larger aircraft are better excited with aileron inputs. Periods can range from a few seconds for light aircraft to a minute or more for airliners.

Related Topics:
Aileron - Rudder - Light aircraft - Airliner

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The name comes from the movement that (Dutch) skaters make when skating on ice.

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Dutch roll is also the name (considered by professionals to be a misnomer) given to a coordination maneuver generally taught to student pilots to help them improve their crosswind-landing technique. The airplane is alternately rolled as much as 60-degrees left and right while opposite rudder is applied to keep the nose of the airplane pointed at a fixed point. (This technique is more commonly referred to as a slip. If the airspeed is allowed to decay the aircraft can stall, and the crossed controls can cause it to spin.)

Related Topics:
Dutch roll - Maneuver - Pilots - Crosswind - Rudder - Slip - Stall - Spin

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