Rolling Around

Jeff Owens

The term "roll" refers to a rotation about the longitudinal axis of the model (think of a line from the nose to the tail.)  The rotation can be a full 360 degrees or, in some cases, less. I will discuss these variations later in this article. For the new pilot this maneuver will introduce some unfamiliar attitudes - the model will be inverted at some point, for example - so it is best to ease into the learning process. It is easiest if we first concentrate on the use of the aileron control by itself. An easy way to start is by doing a ballistic roll. By that I mean that we will only worry about the ailerons and leave the elevator control alone. Start by putting the model into a slight climb, say about 30 degrees up. Then apply full aileron (left or right, it doesn't matter.) As the model completes one full roll and returns upright release the aileron control. You've done your first roll! The plane willl likely be in a shallow dive, so apply some up elevator to return to level flight. If done correctly, the model will have followed an arc from slightly nose high to slightly nose down during the roll - that is why it is referred to as a ballistic roll. You should repreat this until you are comfortable seeing the model execute the roll. Work on your timing of the application of the aileron control so that you enter and exit the roll with the wings level. Do not roll past wings level or stop too soon before returning to a wings level attitude.

Once you are comfortable with this it is time to start working on doing the roll with the airplane remaining at the same altitude throughout the maneuver. This will require some elevator input! Enter the roll now from a level attitude - do not raise the nose as you did previously. As the model rolls inverted apply a small amount of down elevator. Do not do this too soon or too late as this will cause the model to veer to one side or the other. As the roll continues ease the elevator back to neutral. Depending on the path of the model you may need to apply a small amount of up elevator during the second half of the roll. This maneuver willl take some practice as it requires timing the application of the elevator at the correct points to counteract the tendency of the nose to drop - remember how the nose dropped throughout the ballistic roll. The idea is to add just enough down or up elevator to keep the path level. Do not be tempted to "cheat" by using a fast roll rate to avioid the nose dropping. This will just mess up your timing.

Once you have gotten used to executing a single level roll (also sometimes called an aileron roll) it is time to string two of these together. That will require more use of the elevator and using the correct timing. And once you can do two in a row, try for three! In competition there is a maneuver where you do three in row taking about 5 seconds to complete. That should be your goal.

There is a maneuver that combines elements of a loop and a roll called an Immelmann turn. This maneuver is named for the German World War I pilot Max Immelmann who developed it as a quick way of turning around while gaining altitude during a dog fight. The idea is to do half of a loop and when the model is inverted at the top do half a roll to level flight. Many pilots find this an easier introduction to rolling since you only have to do half a roll while at the top of the loop and the model is at a higher (and hence safer) altitude. Another variation is called a Split S. Here you do a half roll and then a half loop to rerturn to level flight at a lower altitude. Again, many find this an easier introduction since you do the half inside loop (up elevator) from the higher inverted position.

At this point you have learned how to do a loop, a roll, and two combinations of half a loop and half a roll. That's four maneuvers! Now you can see the logic behind the Aresti concept of breaking complex amneuvers into combinations of loops, rolls, and straight line segments. In the next article I will delve into more combinations of these basic ideas.