Learning to 3D and 3D well. A Building Blocks Approach. By Jeremy Chinn

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1 Learning to 3D and 3D well. A Building Blocks Approach. By Jeremy Chinn Radio Controlled Aerobatics has always been one of the most exciting elements of the Radio Controlled Airplane hobby. This discipline combines the challenge of coordinating all the available inputs of your airplane correctly and precisely to ensure that it does exactly what you want at exactly the correct time. Get one of those inputs wrong or out of order and the result is ugly, and often disastrous. As the hobby progressed through the years, so did the complexity of the aerobatic maneuvers. Modelers spent countless hours attempting to emulate their full-size counterparts and their movements through the air. IMAC competition even goes so far as to require that you fly a model of a full-sized aerobatic competition airplane. Modelers were always trying to get their models to perform at the same level as their full-scale counterparts most of the time they were short of success. Then at one of the final installments of the Tournament of Championships, QuiQue Somenzini pushed Radio Controlled Aerobatics to another level entirely. QuiQue flew a model which greatly outperformed its full-sized counterpart and flew maneuvers that full-scale pilots could only dream of. With that, the seed for 3D aerobatics had been planted and nothing would hold it back. 3D aerobatics is now the most popular form of flying in the Radio Controlled hobby. Manufacturers frequently throw the moniker 3D at any and every airplane they sell. Competitions just for 3D have cropped up around the country and many specialists have popped up that spend all their time flying 3D aerobatics. Videos flood the internet on a weekly basis of some pilot flying 3D with their new uber-wonder-plane. With all that interest, the hobby has a very large number of people trying to learn to fly 3D. These students of 3D are trying very hard to learn to fly one or more of the cool new maneuvers they ve seen some sponsored pilot fly at a competition or on a Youtube video. Unfortunately, many of these pilots are finding limited or no success. Broken airframes are common and heading home from the field with a multicolored bag of broken airplane parts is often the name of the game for the new 3D pilot.

2 So what are the keys to success for the aspiring 3D pilot? What is needed to ensure that a pilot can find success in learning to fly 3D and do so without breaking the hobby-money bank? In no particular order, they are: Strong knowledge of basic aerobatics Use of a structured approach to learning each of the 3d maneuvers Use of a simulator to help speed the learning process Proper 3D trainer to learn each of the maneuvers Why is a strong knowledge of basic aerobatic maneuvers necessary? So many times when I get asked by a friend at the field or at an event how to do a rolling harrier, I quickly find out that the person asking cannot fly a proper slow roll or even a 4 point roll. It s this basic aerobatic knowledge that helps to provide the right understanding and muscle memory to handle unusual flight attitudes and situations. In many ways, it is similar to wanting to learn to run before you learn to walk. I won t spend a lot of time trying to describe how to learn basic aerobatics there are many more qualified pilots out there to do that, but here are a few good tips: Participate in a local AMA Pattern or IMAC competition The skills you build while practicing even the basic or sportsman routines will be invaluable to your future aerobatic and 3D efforts. Learn to fly all the basic maneuvers such as 4 point rolls, rolling circles and loops in both directions. Even the best pilots have a bias toward rolling one direction or the other, however, they have practiced until that bias is invisible to the spectator. Always practice your worse side more. Learn to trim the airplane properly as part of your basic aerobatic learning. A properly trimmed airplane is easier to fly while doing aerobatic maneuvers from the most basic to the most complex. This same reasoning applies to flying 3D as well. The book Learning to fly Basic Aerobatics by Scott Stoops is an excellent read on the subject. A structured approach is the next item on the list. Again, this is similar to learning to walk before learning to run. By learning each fundamental maneuver, you will have a better chance at finding quick success as you learn to fly 3D. The next article in this series will begin to cover the details of an excellent building block approach to learning to fly 3D. Simulators are one of the most underrated tools and developments in the Radio Control hobby during the past 10 years. Quality and reality of simulators has increased with the same quantum leaps that computers have undergone. There are many simulators out there, and each has its own pluses and minuses. To try and discuss that subject would be many articles in and of themselves. Rather than try to cover that, I ll try to suggest some tips to help you get the most out of

3 your simulator and a training method that can be used with most any simulator to learn quickly and efficiently. Some basic tips which will help you get the most out of your simulator: Don t obsess over flying a particular airplane in the simulator. Instead, try to get an airplane which flies well in the simulator and tune it to your liking. Don t decide you re going to learn to fly 3D in the simulator with an F-14, but at the other end of the spectrum, don t worry if the Extra 300 in your simulator flies better than the Yak 54 fly what works! In general, larger simulator models fly more realistically in the simulator than smaller models do. This is a generalization, but has proven true with every simulator I ve experienced. Learn how to tune your models in the simulator to fly more like your real models. Almost all simulators allow you to edit the characteristics of the models included in the simulator package to suit your needs and to make them fly more like real life. Do not select an airplane in the simulator that is too easy to fly It is supposed to be a challenge. Learn to use the time functionality in your simulator to slow things down. This ability to slow down simulator life when compared to real life is one of the best features of flying in a simulator. Fly your model in the simulator just like you would fly your real model. Go through your same take off routine and landing procedures just as you would in real life. As mentioned earlier, the ability to slow time down in the simulator is one of the most valuable features of the simulator. Slowing down the time function in the simulator allows you to fly maneuvers at a slower pace. Flying at a slower pace allows you to think through each of the required stick movements and corrections as you learn the maneuver. More time to react to incorrect movements is always a good thing as well. When you decide to learn a maneuver on the simulator, start by turning down the time function to approximately 50% of real time. Practice the maneuver over and over until you feel comfortable with it. Once you feel comfortable at that speed, bump the speed up in the simulator by 10% and practice more. Continue this cycle until you are actually flying the maneuver 10% faster than normal speed. By the time you have accomplished this, you will have built the muscle memory necessary to ensure you provide the correct inputs at the correct time to fly your model. You are now ready to try it out in the real world! Another key to 3D success is getting the right airplane to learn with. If you ve followed along so far with this article, then you ve practiced up on the simulator and you are ready to try out the maneuvers in real life. Unfortunately, having the wrong airframe will mean many will fail at this point and won t progress any further.

4 The right airframe has to do many things. It must be tough for the unintentional mishaps that will happen, it must be simple to repair, and above all, it must fly 3D very well. The two airplane types that fit this bill very well are foamies and.40 size profiles. Both types of airplane have a relatively low cost to build and as a result a relatively low cost to repair. Those factors alone mean you ll spend more time in the air than repairing at the workbench. Finally, there are countless examples of both type of airplane which fly exceptionally well. If you are put off by the appearance of a profile, get over that issue and use one to learn to fly 3D, then sell it to a buddy so he can do the same. A few types of airplane to avoid for learning to fly 3D: Giant scale airplanes are very bad 3D trainers. Most giant scale airplanes are easier to see and fly somewhat slower than smaller airplanes. However their higher cost and higher complexity adds significantly to the fear that many pilots will have when flying them. It is difficult or impossible to learn a new skill when you are faced with constant fear of hurting the airplane..40 size full fuselage airplanes also make poor 3D trainers. Most examples in this category have cost and complexity induced fear similar to giant scale airplanes mentioned above. Additionally, they typically have very high wingloadings when compared to a same sized profile airplane. The result is an airplane that flies poorly and is difficult to repair when damaged. Again, a bad combination for someone who wants to learn to fly 3D. Small full fuselage electric airplanes. This category of airplane has become extremely popular with the increased availability of good quality electric gear, motors and batteries. Unfortunately, the comments for the two airplane types mentioned above apply very strongly to this category as well. So that is our starting point. Get the right gear and get ready for the next section.

5 Getting the Harrier Down! A Building Blocks Approach By Jeremy Chinn If you have followed along with the previous articles, you now you have a simulator to learn on as well as the right kind of airplane to learn with. This is a point at which many people just begin banging the sticks around and thrashing the airframe around the field. Not only does this not necessarily turn into the safest situation, but it does not often yield to success. To learn to 3D well, you need to learn with a building block approach that builds a good foundation of basic 3D maneuvers and progresses from there. This progression will use much of the basic aerobatic knowledge you have previously learned to control the airplane in all attitudes and situations. While most people think the core maneuver to flying 3D is the hover, that is unfortunately incorrect. The most basic and fundamental maneuver for learning to 3D is the harrier. The harrier is a part of a majority of 3D maneuvers and skills learned during harrier training help build rudder control skills necessary for more complex maneuvers. To learn to harrier correctly, we are going to use another simple maneuver called an elevator. Learning to harrier this way initially allows this first maneuver to be flown at a higher altitude and with an easy escape route. Start by climbing to an altitude of 5 mistakes high. Level the airplane at center field with the nose into the wind and cut the throttle to idle. When the airplane has slowed significantly, hold full up elevator and allow the airplane to fall. If your airplane is set up correctly with an appropriate center of gravity and control throws, it should descend slightly nose down or level. An idle set too high will cause the airplane to descend nose high. As the airplane descends, use the ailerons to hold the wings level. During the descent, the wings may rock back and forth. Careful correction with the ailerons will help correct this problem with most good designs. When the airplane has reached an altitude of 1 mistake high, decrease the pressure on the elevator and increase the throttle to fly out level. You have just completed an Elevator! Congratulations!!!! Continue practicing this maneuver until you are comfortable with the airplane descending in this manner. Next up, prepare to fly an elevator just as you did before, however for this round of exercises, you should begin to use the rudder to steer the airplane as it

6 descends. Remember to use the ailerons to keep the wings level during the descent. Try descending while steering the airplane through a gentle circling descent and exit as before. Continue flying this exercise until you are comfortable using the rudder to steer. This exercise may feel odd to many sport pilots who are not used to using the rudder on a regular basis. In the next phase, we will begin the elevator just as before and use the rudder and ailerons. As the airplane reaches the midway point of its descent, begin to increase the throttle until the nose rises slightly. The airplane will also move forward more than in previous exercises and its rate of descent will slow. Do this repeatedly until you feel comfortable increasing the throttle and maintaining control of the airplane. Once you are comfortable descending in this increased throttle state, allow the airplane to descend to 1 to 2 mistakes high and increase the throttle more while easing off the elevator backpressure. Your goal at this point is to find a point of equilibrium where the airplane maintains a nose up attitude of approximately 30 to 45 degrees while slowing the descent to no altitude change. When you can successfully complete this last exercise, you have successfully flown a harrier. You can successfully control the heading of the airplane with the rudder and its attitude and rate of descent with a combination of elevator and throttle control. Its now time to take your efforts to the next level. Once you feel comfortable finding that balance between elevator backpressure and throttle input, you need to take the next big step. In the next phase of this exercise, you are going to fly at a very low level. This is a point at which many students get very uncomfortable. They reason that since they are closer to the ground, they are more likely to hit the ground. That is not an unreasonable thought, however it fails to take all the factors into account. Learning to 3D- especially learning to harrier at a very low level is absolutely the best place to perfect your harrier. Optimally, you ll fly with your tail 1 to 2 feet off the ground. By learning to harrier at a low level, you: Fly at an altitude and proximity to yourself that allows you to see every movement of the airplane no matter how small and react to it promptly to keep the airplane flying the way you want it. Keep the airplane low so that in the event it does get into and out of shape attitude, it does not have enough time or altitude to build up momentum that will cause significant crash damage. Impress your friends! Start this phase by flying low level straight line runs down the runway into the wind. Remember to be courteous to your fellow flyers and yield the runway to

7 those that need it Pilots taking off or landing always have the right of way. If you get uncomfortable with the airplane at this altitude because of a gust of wind or other factor, use the ailerons to level the wings, cut the throttle back somewhat and let the airplane drop to its landing gear. As you get more and more comfortable flying your harrier down the runway, begin to add turns into your exercise. Start with circles one direction, then the next. When you feel comfortable flying circles in a harrier, modify your exercise to include figure-eights over the runway. These simple exercises are a great way to build, refine and improve your fundamental 3D skills. You now have a great foundation to begin building more 3D maneuvers into your repertoire, so what is next? Before moving to an entirely different skill, you need to go back to the beginning of this harrier lesson, but progress through it inverted. A successful inverted harrier is another important building block of learning to 3D. As you move through the inverted version of the harrier lesson, remember that your rudder and elevator require inputs opposite of those you use in an upright harrier. Most people find it extremely helpful to use their simulator at a slower time rate to build this skill before moving to the real world. Becoming proficient at flying your airplane in a harrier is one of the most important building blocks or fundamentals of becoming a great 3D pilot. Don t be afraid to take your time moving through these exercises. Some pilots will progress through the Harrier lesson in a weekend. It may take others a month. You should also not be afraid to break this lesson out again when you have progressed past it.

8 High Alpha Knife Edge Flight By Jeremy Chinn In the Previous articles, you got the right equipment (both virtual and real) and you learned how to fly a harrier. Then you expanded your 3D horizons by learning to fly an inverted harrier. You are well on your way to building a solid base of fundamental 3D skill. Next in line is another fundamental skill which can be built upon later. It is time to learn to do a high alpha knife edge. If you followed earlier suggestions to build your basic aerobatic skillset, you learned to fly knife edge during that effort. If not, then go back and learn to fly knife edge flight. Make sure you can fly both left tip down and right tip down, and both orientations with the top and the belly of the airplane towards yourself. This basic aerobatic skill can also be developed quickly using the simulator. If and when you are comfortable flying regular knife edge flight, you are ready for the next step in your 3D eductation High Alpha Knife Edge. This name is really just the common name for flying knife edge at a high angle of attack. To learn this skill, start by flying a regular knife edge down the field repeatedly. As you fly, gradually increase the rudder deflection, while balancing that against changes in throttle. Some airplanes require more throttle, some less. All have a point of equilibrium that you must find on your own. This skill can be learned at any lower altitude, but I ve found that having the lower wingtip at around eye level is the most effective. This altitude gives enough time to roll the airplane back to level in the event of a problem but is not too high to allow good vision of the airplane. You may find that the airplane you are flying will require a higher angle of attack in high angle of attack Knife Edge than it did for harrier flight. This is because the fuselage typically has less area than the wings do, and thus requires a higher angle of attack, more power or both to maintain a flat heading. You may also find that you need some aileron correction or elevator correction to keep the airplane on the same heading while in High Alpha Knife Edge. Fly the airplane in this case rather than relying on a mix. I ve found that rarely are mixes effective in maintaining high alpha knife edge when compared to regular knife edge. Perform the same exercise in both directions down the field, and both directions with both orientations to yourself. When you feel comfortable in all orientations, begin to make circles with the airplane. Use your elevator to steer the airplane in your intended direction.

9 Practice this skill repeatedly until you feel comfortable in all attitudes and orientations, and turning in all directions. When you have mastered High Alpha Knife Edge and flying upright and inverted harriers, you are ready to move on to two more advanced 3D Skills The Hover / Torque Roll and the Rolling Harrier. Each will be covered in upcoming articles.

10 Hovering and Torque Rolling By Jeremy Chinn In past installments, you got the appropriate virtual and real airplanes to fly as well as practice methods to help speed your learning. During that time, you also built two of the fundamental building blocks necessary to learning 3D aerobaticsthe harrier and the high alpha knife edge. It is now time to put those skills together to learn an advanced level 3D skill the Hover. Why is the hover an advanced level 3d skill, and why did you learn to harrier and high alpha knife edge first? When hovering or flying a torque roll, you must use the tail of the airplane to control the airplane and keep it in a state of balance or equilibrium while hanging from the prop disk. To do so, you must be very competent with the rudder and the elevator to steer or correct the airplane. Learning to fly the harrier and the high alpha knife edge teach those skills rapidly and effectively. The other reason is based on safety and airframe longevity. When an airplane falls out of a hover or a torque roll, it always passes through an attitude similar to a harrier or a high alpha knife edge. Since that attitude also generally requires slower movement to maintain altitude, it is generally best to catch the airplane as it falls out of a hover or torque roll when it reaches harrier or high alpha knife edge flight. Once again, this is a maneuver which is much easier to learn on the simulator first using the reduced time method and then transfer to real life. The optimum conditions to learn to hover start on a day with a mild constant breeze. Start with the airplane in a low (1 to 2 feet off the ground) upright harrier flying into the wind. I like a distance of about 40 feet away from myself for this exercise. Chose a spot over the field and gradually increase the throttle while initially increasing the elevator backpressure at the same time until the airplane is totally supported by the propeller disk. Inevitably, the airplane will begin to wander or lean left, right or another direction. Once the airplane gets out of hover position, you have two choices to exit the maneuver Go to full throttle and climb up and out of the hover. This is most pilots gut reaction and is fairly effective, however, if the airplane is totally out of shape, or in an orientation the pilot is not comfortable with, going to full throttle in that position can be scary or even downright dangerous.

11 The better alternative to the full throttle exit is to allow the airplane s nose to fall until the airplane is either upright or inverted on the wing. The pilot can then fly out of the maneuver easily in either an upright or inverted harrier which was mastered earlier. Exiting in this manner is generally safer and also allows the pilot to get back into hover position more quickly. Some things to avoid for the person learning to hover: Many people try to enter a hover by flying in at high speed and pop the nose up rapidly to enter the hover. Unfortunately, in this case, the airplane has a large amount of energy to bleed off before it can hit the sweet spot and initiate the hover. Don t waste time trying to learn to hover 2, 3 or even 4 mistakes high. When at that altitude, there is no way you can see the airplane well enough to make the right corrections and keep in the hover. Continue this exercise until you can enter a hover at will and enter and exit the hover safely and fully under control. For extra practice, try entering a hover from a high alpha knife edge or inverted harrier.

12 Rolling Harrier!!!!!! By Jeremy Chinn The next 3D maneuver in the series, the rolling harrier or harrier roll, relies heavily on the basic aerobatic skills you built up prior to learning to fly 3d. If you can t fly the basic aerobatic rolling maneuvers such as a slow roll, 4 point roll or rolling circle, you will have very little success attempting to do a rolling harrier or a rolling harrier circle. Take the time to learn those skills first. Earlier in the series, you learned the upright and inverted harrier as well as the high alpha knife edge. To simplify matters, a rolling harrier is simply harriers and HAKE s strung together end to end and flown with a particular rhythm. Additionally, varying that rhythm allows you to steer the rolling harrier straight, left/right or up/down. There are a few common mistakes that many pilots make which you should try to avoid: Don t practice this maneuver only one rolling direction, as that will build a bias into your flying and make later maneuvers more difficult. Always fly the maneuver with both rudder and elevator inputs for altitude and heading correction. Flying with only one or the other results in a choppy looking maneuver which is much harder to control. Try this maneuver on the simulator first and then transfer to real life. Flying rolling harriers properly comes from building muscle memory and rhythm, which can be done much more quickly on the simulator using the reduced time method. To begin the rolling harrier, start with the airplane in an upright harrier flying into the wind two to three wingspans high. With full control of the airplane, use the ailerons to roll the airplane to a high alpha knife edge and hold it there. Next, roll the airplane to an inverted harrier and again hold it there. Follow with a roll in the same direction to high alpha knife edge. Complete the sequence by rolling the same direction back to upright harrier. Practice this sequence of events repeatedly until you feel comfortable transitioning from one position to the next. Next, decrease the amount of time you hold the airplane at each position and practice the sequence again. Continue practicing the sequence and reducing the hold time at each position until you can roll the airplane through each position without stopping the roll. Congratulations, you ve just done a rolling harrier. To build this skill, practice it in both directions and from starting points of upright and inverted harrier as well as from both orientations of high alpha knife edge. Practice also stringing harrier rolls together seamlessly until you can fly the entire length of your runway without stopping the rolling harrier.

13 For extra credit, learn to steer the rolling harrier by changing the timing of your rudder and elevator inputs. This aspect of the rolling harrier is learned most quickly on the simulator using the reduced time method.