Do Dutch Rolls Help Pilots Land Airplanes Better?

Landing is the most challenging maneuver most pilots will ever perform. Not surprising, it is the most dangerous few moments of any trip. I stumbled on an exercise that shortened the time that pilots needed to learn landings and dramatically improved their landing skills far more than I ever thought possible. It has become known as the 'Slow Dutch Roll.'

A Dutch roll is a rhythmic maneuver that most instructors agree is about as useful as patting your head while rubbing your tummy. In contrast, the Slow Dutch Roll proved to be a very powerful tool.

When executing an ordinary Dutch roll, you keep the nose of the airplane pointed at a speck on the horizon while rapidly wagging your wings with your ailerons and holding the nose steady with your rudder pedals.

When you move the stick to the left, the nose wants to swing to the right forcing you to step on the left rudder pedal, but not quite as much as you would in a turn. Then, as the bank increases, you have to step on the other pedal to keep the nose steady. And so the exercise continues. But to what purpose?

My colleagues and I don't like this exercise for two reasons. First, aileron - rudder coordination should be focused on keeping the ball in the center. To put it differently, a good pilot could put a cup of coffee on the instrument panel and go through a series of turns in both directions without sloshing the coffee. He or she would have to coordinate the ailerons and rudder properly to succeed. During a Dutch roll, the coffee would be all over the cockpit. Our second objection is that, in addition to teaching bad habits, there is basically no region of normal flight where the pilot would execute a traditional Dutch roll. We view an ordinary Dutch roll as somewhere between worthless and counterproductive.

In contrast, the Slow Dutch Roll (SDR) teaches you skills needed in almost every takeoff and landing as well as some other very useful skills.

I don't hold a patent or copyright on the SDR. It wouldn't surprise me if some other flight instructor discovered it before I did. But it makes better pilots. I would like as many pilots and instructors as possible to know about it and use it.

SDR, much like the traditional Dutch roll, requires you to aim the nose at a point and keep it there while changing the angle of bank. By executing it very slowly, it teaches you, among other things, precisely controlled crosswind landings and takeoffs.

To get the maximum benefit from SDR, you should practice it at constant altitude and various airspeeds including slow flight with wheels down and flaps extended. Then do the same thing while gliding rather than at constant altitude, eventually practicing SDR at speeds just above a stall with the airplane configured for landing. Depending on your skill, you might start SDR practice by simply trying to keep the airplane's heading constant as you change the angle of bank slowly.

I recommend not only changing the angle of bank slowly, but holding bank constant for as long as 30 seconds or more. You might be surprised at what happens during these periods of constant bank. With a wing down but the airplane not turning, the wing's lift will start to move the airplane in the direction of the bank. As it accelerates to the side, the relative wind direction changes. This wind shift requires you to change the position of both rudder and aileron controls to keep constant bank and heading.

This continuous change in control position while maintaining a constant attitude is the added bonus of SDR. It teaches that essential skill that all good pilots have. To be a good pilot, you must be able to fly the airplane by putting it in the right attitude regardless of where the controls are. If you must move the controls continuously to maintain the proper attitude, you will neither know nor care; you simply focus on maintaining the proper attitude. With SDR, you can practice this skill at a safe, low-stress altitude rather than during landings.

Having mastered SDR, you have mastered 90% of the skill required to make safe, precise landings. In a light plane in particular, you must keep the airplane pointed at the far end of the runway while keeping the wind from blowing you off the runway. By mastering SDR, you have mastered the controlled sideslip required in the vast majority of landings. By mastering SDR you have also mastered the art of attitude flying. You have learned to put the airplane in the attitude that you want and hold it there regardless of wind shifts and diminishing airspeed - an absolutely essential skill in safe, smooth and precise landings.


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Douglas Daniel is long time pilot, flight instructor, software engineering manager and author. His department developed the software for the out-the-window-displays for the space shuttle, F-117, RS-71 and numerous other exotic airplanes. His writing focuses on flying techniques designed to make flying easier and safer. If this was interesting, visit his website at http://www.FlyingSecretsRevealed.com/flying_questions/