Rolling on a heading
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 "stick-and-rudder" technique. The aircraft is alternately rolled as much as 60 degrees left and right while rudder is applied to keep the nose of the aircraft pointed at a fixed point. More correctly, this is a rudder coordination practice exercise, to teach a student pilot how to correct for the effect known as adverse aileron yaw during roll inputs.
This coordination technique is better referred to as "rolling on a heading", wherein the aircraft is rolled in such a way as to maintain an accurate heading without the nose moving from side-to-side (or yawing). The yaw motion is induced through the use of ailerons alone due to aileron drag, wherein the lifting wing (aileron down) is doing more work than the descending wing (aileron up) and therefore creates more drag, forcing the lifting wing back, yawing the aircraft toward it. This yawing effect produced by rolling motion is known as adverse yaw. This has to be countered precisely by application of rudder in the same direction as the aileron control (left stick, left rudder – right stick, right rudder). This is known as synchronised controls when done properly, and is difficult to learn and apply well. The correct amount of rudder to apply with aileron is different for each aircraft.