Many of the students that come to me for flight instruction in Weight Shift Control have significant airplane experience. The typical airplane pilot loves the first 15 exhilarating minutes they spend in the trike, then struggle with the next 30 minutes as I hand over the controls to let them learn to fly it, then back to loving it after an hour or so when the controls have become intuitive to them. If they don't press all the way through the first hour, they walk away not liking weight shift control. That is a natural reaction, because when you go from something you are good at (airplane flying) to learning something new (weight shift control aircraft) it is natural to feel some frustration until you get good at the new way to fly. It doesn't take long until the control becomes intuitive, but it does take most pilots up to an hour. To make an analogy, I'd say it is about like learning to ride a motorcycle when you are already used to driving a car. A 'motorcycle of the sky' is the best way to describe the experience of flying a weight shift control hang glider trike.
Here is an article I wrote to help my students with airplane experience transition to Weight Shift Control. It was published in AeroConnections magazine last fall. I also got the cover shot above, flying my Krucker Cygnet over Destin Florida with a student.
Weight Shift Control for Airplane Pilots
Some say that weight shift control is not ‘intuitive’. But I only hear that from people who haven’t actually done it. Give weight shift control an hour or two and you will find it quickly becomes intuitive. I fly both airplanes and weight shift control, and switch between the two without thinking about it. You can steer a car with your hand at the bottom of the steering wheel and still have intuitive directional control. But if you overthink it you’ll realize that your hand goes left to make the car go right. We intuitively understand that the direction of rotation of the wheel is what matters, not the direction your hand moves. Our brains easily make this adaptation. Weight shift control is like steering with your hand on the bottom of the steering wheel. After you gain some practice with weight shift, you will soon reach that point of being able to do it without thinking about it. When you first flew a plane, basic flight control took most of your attention. After some practice, you could fly the plane, tune radios, look at charts, etc. all at the same time because basic flight control became easy. Controlling weight shift for the first time will set you back down that learning curve where you will have to think about basic flight control for the first hour or two until your brain begins processing the information automatically in the background.
Airplane pilots first studying weight shift control often say “The controls are opposite” But telling yourself “just do the opposite of what you would do in an airplane” would be dangerous mental exercise during the stress of a turbulent approach to landing. So here’s a much more useful way to wrap your brain around the weight shift control concept. You have direct control. You directly bank the wing. You directly pitch the wing. Your control bar is rigidly coupled to the wing you are flying. To give that some context, let’s compare with airplane. With airplane, you have two lifting surfaces involved, the main wings and then the tail. To dive the airplane, we push forward on the stick or yoke. That deflects the elevon down, which forces the tail up, which in turn points the nose down. It takes a series of events to get the airplane pointed where you want it. Weight shift control, in contrast, is direct. Sit in a trike (or an imaginary one at home on the couch) with your hands on the control bar and watch the wing as you move the control bar. If you want the wing to point down, you directly pull it down. To point the nose up, look at it and push it up. To bank left, you physically pull the left wingtip down and push the right wingtip up. In flight, all that is needed is a gentle control input, but imagining these control motions in an exaggerated way will help you get the control concept firmly planted in your mind.
Next we’ll talk about applying these pitch and roll control inputs while you are flying. The good news is that pitch will almost take care of itself. Most trike wings are very stable in pitch, so that part will take care of itself for most aspects of the flight, provided that you relax and let the wing remain in its pitch trim position. That means being careful not to pull in or push out on the control bar as you move it left and right for turning inputs. That will leave us free to concentrate on roll inputs that bank the wing to turn. The typical trike wing is much more sensitive in roll than in pitch, so you will be able to turn left and right with minimal effort.
Here are several ways to think about these turning control motions. They all do the same thing, so just use whichever ones are easiest for you to remember. The control bar is always parallel with the wing. So if you want to level out the wing with reference to the horizon, put the control bar level with the horizon. If you want to turn left, bank the wing to the left by putting the control bar in a left bank. If you are in a turn and want to level out, directly force the wing level. It won’t require much force, but is a direct way to think about it. Whatever bank you want, command it directly. To roll into a bank, decide which wingtip needs to be higher and push that wingtip up. To ‘undo’ the bank and roll level, pull that high wingtip down. That shifts your weight to the high side and gets you back to level flight.
So that’s how to think about which direction to push and pull for left and right turning. Now let’s talk about practical application of these control inputs. The bottom line is “gently”. Subtle control inputs are all that will be needed unless the air is very rough.
Pitch control
The wing has an inherent trim position that was set when the wing was installed on the aircraft carriage. The pitch trim position is where the control bar will be when you are neither pulling in nor pushing out. If you are giving a trim input (pulling in or pushing out) and let go, the wing and control bar will return to trim. The wing is dynamically stable in pitch. Trim will give you a good rate of climb and good glide, so that is how we want to fly most of the time, especially in our first lessons. Allowing the wing to stay at trim will allow you to focus on turning inputs.
Turning inputs
Give these as an impulse—a quick little pull in the direction you want to go. Make the control input as brief as possible, and then relax. Evaluate whether that input was enough, and give another small input if needed. If you hold the input too long, you will overbank. Be prepared to give opposite control input to control your bank. To decrease bank, pull the high side down.
Nose wheel steering.
Once again we are directly controlling the front wheel for steering. Whichever way you want to go, you must point the wheel in that direction, just like the steering on a bicycle or motorcycle. If you over-analyze this, you may see that technically you push with your left foot to turn right. But you don’t need that analysis to steer a bike, and you don’t need it to steer a trike either. Let it be as easy as riding a bike. Simply point the wheel where you want to go.
In conclusion. Weight shift control will quickly become just as intuitive to you as whatever you are flying now, so go ahead and give it a try. Most people catch on first flights. Doing some ‘mental flying’ from the comfort of home or office will give you a great head start preparation for your first weight shift flight. So here’s a final exercise. Stand up and hold your hands out in front of you like you are typing or playing piano. That is where they will be when you are trike flying. Now roll your body into a right bank. Which way did your hands naturally move? They moved exactly how you would need to move them to turn right. Bank your body left and once again your hands will move the correct way for weight shift control. Now look down at your feet and notice how your hands move as your body pitches down. That’s the motion for a pitch down in weight shift. Watch your hands move forward as you pitch your body back to level flight or climb. That is weight shift control! Natural and intuitive.
About the author:
Michael Percy has been flying weight shift control since 1990. He is an FAA Certified Flight Instructor (CFI) for
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