Dutch roll

A Dutch roll is a simple aerobatic 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.)

The term Dutch roll can also refer to an undesirable instability in some airplane designs. The airplane "wallows" in rolls and yaws left and right usually of just a few degrees. This makes for a very uncomfortable ride.