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Just because a person is good at something does not necessarily mean he can teach it. Some of the best pilots freely admit that they do not have the patience to teach beginners. Also, teaching requires an ability to see things through the eyes of the beginner and to modify the discussion accordingly. Not everyone is cut out for this. It is the intention of this text to teach experienced pilots how to teach RC flying. While it will be most useful to beginning instructors, even pilots who have been teaching for some time may find many of these points helpful. Index:I. What It TakesInstructors at club flying fields are always very busy, especially during evening and weekend flying sessions. There never seems to be an abundance of instructors, even during designated instruction times. For this reason, many newly proficient pilots should consider becoming instructors. While there are many ways that club members can give back to their club, instructing for a flying season is one of the most rewarding ways. There are many ways to teach radio control flying and no two (2) instructors will totally agree on how every concept along the way should be related. The methods outlined here are rather simplistic, yet they have been proven during ten years of instruction and have always worked well. These methods can surely be improved as each instructor develops his own teaching style. The goal of this instruction program will be to get the student to the point where he can fly by himself. While instructors may also wish to assist their students with learning aerobatics as well, this text will only address basic flight. When using these teaching methods, there are four phases (or progression levels) a student must achieve to get to the point where they can begin flying on their own. This makes it very easy to teach, since every technique needed for flying can be organized into four basic phases. It also helps by limiting the number of things a beginner must master as he learns how to fly. While certain techniques described during each phase can eventually be mixed and matched to the instructors teaching preferences, it is recommended that the instructor thoroughly understand the entire process before he begins to change anything. This text will stress the teaching of flying skills only. The assumption is made that the instructor or other club members can relate the basics of aerodynamics and flight, control surfaces, and in general, what makes an airplane fly and will offer assistance in helping the beginner to pick his first airplane, understand flying safety, and start and maintain his engine. There are many things that must be related before flight training can begin. Here are a few special pointers for beginning instructors:
In section one, there are several discussions aimed at helping the student. This section includes the most commonly asked R/C questions, a presentation on what makes the best trainer airplane, a discussion of safety, and the basics of engine tuning. While these presentations are directed to the beginner, the instructor is urged to read the information to help with the ability to relate these important topics to beginners at the field. The instructor can also copy this information and give it directly to students. Teaching R/C flying is broken into four (4) basic phases. In any form of teaching, it is good to limit the number of things a student must learn within a given period of time.
While this may sound overly simplistic, to get to the point where the student is flying by himself, every technique fits into one of these four categories. Before allowing a beginner to fly, there are several things that the instructor should have explained. The student should know the basics of aerodynamics and flight. He must know the stick controls on the transmitter and the function of each. The student's airplane must have been checked by a pre-flight instructor and have had at least one trim flight. Instructors tend to teach what they know in the same manner that they know it. There are several alternatives to almost every important function of flying. Good instructors recognize that their own ways are not only ways of doing everything. Thirty (30) years ago, students were taught to fly with their thumbs. Most instructors still fly this way although flying with fingers is a better method. Some instructors have tried to get comfortable with fingers but fail to do so. When an instructor is teaching a new person to fly, it is suggested that he start the student from the beginning using his fingers. The further a person progresses and the more precisely he wishes to fly, as in pattern flying, the more important it is that he be able to fly with their fingers. It is very difficult to switch to flying with fingers after learning to fly with the thumbs. Beginners have a common problem when it comes to mastering turning. After entering a turn, they tend to forget which way they are turning and give the wrong aileron to exit the turn, sending the plane deeper into the turn. There are several ways the instructor can help the beginner with this problem. One way is to get him to turn his body to face the heading of the plane. If he is looking in the same direction as the plane is flying, it will help him to remember which way the plane is turning. Another way is to get him to keep repeating aloud from the beginning of the turn which way he is turning. With either method, the beginner will eventually become comfortable turning and not need a crutch. The instructor should get the student to stand in a stationary position when flying and get him to keep saying aloud the direction he is turning. This is especially important if a trainer system is not being used. When training first begins, the instructor should try to keep the throttle setting just high enough to keep the plane in the air. This ensures smooth docile performance and minimizes the natural tendency to over-control. It also helps the student to make level turns. However, some beginners catch on more quickly when the engine is running faster. For some people, a responsive airplane is easier to master than a docile one. Either way, the instructor will eventually need to have the beginner practice at all throttle settings from idle through full throttle. Instructors tend to disagree on how much control surface movement should be used. Since beginners have a natural tendency to over-control, many instructors like to set up trainers to be very docile by minimizing control surface motion. This means the beginner must move the sticks quite a bit to cause a reaction from the plane. However, it is better to keep the plane rather responsive for three reasons. First, the beginner must eventually learn the precise control motions needed with sensitive control surfaces either on the trainer his next plane. Second, on windy days minimal control may not be enough to cause any response from the airplane in certain attitudes. Third, the instructor needs the plane to be responsive enough to get out of precarious attitudes. Beginners are normally taught to fly without ever using the rudder stick except for steering on the ground. Most R/C airplanes, especially trainer planes, turn quite well with only a combination of aileron and elevator. Rudder coordinated turns make look much nicer and rudder is helpful when landing in a crosswind but it is better to keep turning as simple for beginners to master as possible. However, if the instructor feels strongly that the beginner should learn coordinated turns from the beginning, by all means, he should teach them in this manner. If teaching realistic flying, the R/C pilot will make two (2) turns during the final approach. One turn will bring them ninety degrees to the runway and the other will bring them right on the middle of the runway. To simplify this, beginners can be taught to make a single 180-degree sweeping turn during final approach. Most beginners can learn more easily on calm days but those who live in windy areas may never fly if they wait for perfectly calm days. However, there comes a point when the wind is blowing so hard that it will be impossible for the beginner to control the plane. For the beginner's first ten flights or so, the instructor should limit teaching to when the wind is blowing under 5-8 miles per hour. As the beginner progresses, he should be allowed to fly on windier days. The student has not truly mastered flying until he can fly with winds around 10 MPH. II. Before Flight InstructionInstructors tend to get most of the questions from people who are considering getting into the hobby. Once someone has begun learning to fly, instructors are bombarded with questions related to all facets of the hobby. Even after a beginner has learned to fly, he still asks an instructor when he has questions, especially about aerobatics. This section is devoted to handling the most common questions and problems a beginner has. As an experienced pilot, the instructor already knows much of what is presented in this section but this presentation should help the instructor with his ability to relate what he knows to his students. Also, much of this section can be simply copied and given to beginners with questions. In this section, some brand names and actual models are mentioned but this is done for the sole purpose of offering comparisons. It is not intended to endorse or criticize any of the products mentioned. There are numerous radios, airplane kits, ARFs, engines, and flying accessories of excellent quality. In fact, the modeler really has to go out of his way to find a poor product in this hobby. Most beginners to the hobby tend to have the same set of questions as they enter into the R/C airplane hobby. This is a summary of these questions and with brief answers to each.
Trainers in .40 size range offer the best compromise in stable flight and economy. While the beginner can go smaller to keep costs down, the .20 size airplanes tend to be a little unstable, especially in wind. If cost is not a concern, .60 size trainers tend to be substantially more stable than .40 size trainers, especially in higher winds. The first recommendation for and engine for a beginner is to buy one with a proven track record of reliability. Experienced flyers at the local field can offer recommendations. OS engines tend to have the best reputation in this regard. While the beginner can get more power for the money with other engines, he will not want to be spending his precious flying time fine tuning a temperamental engine. Also, as he begins learning how to land, he will want a good reliable response from idle to midrange for practice approaches. The beginner should keep the plane slightly overpowered. As he begins taking off, a good strong engine makes the procedure much easier. If his airplane has barely enough power to get off the ground, taking off can be quite a challenge. This extra power is also very handy when practicing approaches and for gaining altitude quickly. Also, when he has learned to fly, a good strong engine will be needed for his next airplane. Beginners to R/C flying vary dramatically when it comes to building skills. Some may be building their very first flying model and find it quite challenging while others may have built other types of flying models and find it rather easy. The kind of airplane has a lot to do with how difficult it is to get into flying condition. ARF's tend to be rather easy, requiring little more than final assembly while kits can be much more challenging. Also, correctly mounting radios and engines can be somewhat difficult, even for ARF airplanes. For these reasons, beginners are urged to have their planes checked for air-worthiness. Instructors can check for problems that need to be corrected. Common mistakes that must be corrected before the plane can be flown include having servos activate control surfaces in the incorrect directions, not placing foam rubber around the receiver for padding, not properly joining wing halves, not correctly gluing hinges, and improper center of gravity point. These are but a few of the many things that can cause an airplane to crash and the instructor must be on the lookout for many more. Also, there may be things an instructor finds that may not cause the airplane to fail but should be repaired in the near future. For example, certain control surface hardware; i.e. clevises, control horns, and linkages, works better than others. An instructor may be willing to help a beginner today, but may ask that some things be changed before further help will be given. III. Teaching How To Master Turns & Level FlightThe objective is to get the student to a point where he can keep the airplane in the air with no help from the instructor. Though the plane may still be "flying the student" to some extent at the end of this phase, at least he should be to the point that he is not constantly fearing for the airplane as they fly. The assumption is that at this point that the training airplane has had a trim flight and any necessary control surface adjustments have been made. This also assumes that the beginner understands the basics of aerodynamics and flight, including knowledge of the influence each control surface has on the airplane. Finally, the assumption is made that the beginner understands the rules, especially the safety related rules, of local flying field. The time it takes the student to master this phase varies dramatically. There have been students who have done so on their very first flight but it usually takes longer. Regardless of how long it takes, students should not get the feeling that they are in a race to see how long it takes to master any phase of learning to fly. Beginners tend to think they should master flying their very first time out. When they do not or whenever they think they are not progressing fast enough, they tend to get down on themselves, especially if another beginner seems to be progressing faster. Part of the instructor's job will be to keep them from getting discouraged. He must make it clear that everyone picks up the hobby at a different pace. He should relate the problems that he had when he was learning to fly. He should ensure that the student is having fun. If it is fun, nobody should care how long it takes. He should tell the student that if he pushes too hard, the problems will only get worse. The instructor should begin on the ground by explaining the basics of turning. He should explain that turning is basically a three-step procedure:
The instructor should demonstrate turning with hand movements as well as on the stick of the transmitter. He should explain that even trainer planes tend to be quite responsive and that only a little movement of the stick will be sufficient to maneuver the plane. While the student cannot really get a feel for flying while on the ground, the instructor must prepare him for what to expect in the air. If the plane has ailerons, it is recommended that the beginner ignore the rudder when turning for a while. R/C airplanes, especially trainers, turn quite well with a simple combination of aileron and elevator. While the instructor may eventually wish to teach the beginner rudder coordinated turns, this tends to substantially complicate the learning process, especially early on. If the instructor intends to teach rudder coordinated turns, he should wait until the student is well along in phase two before this more complicated turning method is introduced. On the student's first flight, the instructor should begin by demonstrating a turn. The plane should be in an attitude where the student can see both the plane and the transmitter with held up near eye level. This way, the student can see the small amount of control the instructor is giving. After entering the turn, the instructor should stress how important it is to maintain the turn with up elevator. He should also demonstrate how a trainer airplane tends to self-correct, meaning minor aileron corrections may be required to hold the bank angle. Finally, he should demonstrate exiting a turn with opposite aileron control. The instructor may want to demonstrate this in both directions, stressing the three-step nature of turning; bank with aileron, hold the turn with up elevator, straighten with opposite aileron. The assumption is being made that the student is using a trainer system. The instructor should begin by getting the plane into a perfect turning position. The instructor will need to make it as simple as possible for the beginner's first few tries. It is best to begin at a safe altitude by aiming the plane toward one of the near corners of the field, left or right. This way, soon after the instructor gives control to the student by holding the trainer button on the master transmitter, they will immediately begin the turn. The student should be instructed to turn the plane in a direction away from the pit area. It is quite likely that the student will immediately roll the plane over on its back, so the instructor must be ready for anything when he gives control to the student. Again, the instructor determines when to take control. For the student's first few attempts, the instructor will probably have to take control soon after he pushes the trainer button. He should not be afraid of hurting feelings by taking control. As soon as the student is in trouble and the instructor takes control, he can correct the problem and set the plane up again for another turn attempt. The instructor sets the rules for when he takes control. Early on, beginners are told that there will be times when they may be in control of the airplane yet the instructor will still take control. If it appears that the student might eventually cross over the flight line or fly over the pit area, the instructor immediately takes control. While it is possible that the student may have been able to continue flying without crossing the flight line, it is better not to take any chances where safety is concerned, especially on the student's first few flights. While learning how to turn, students tend to lose altitude in each turn they make. When the plane descends past a preset altitude limit, the instructor should take control, even though they may be doing rather well. This also gives him the goal of keeping the airplane above the limit. If the plane gets so far away that it becomes difficult to see, the instructor should take control. The instructor may also want to set a similar rule based on his own comfort level. The student should be aware that if they get the plane into an attitude that is uncomfortable for the instructor, he will take control. This may not be caused by a problem or mistake on their part but simply because the instructor does not want the plane to get into an attitude from which the instructor cannot recover. Though the instructor may have explained the three steps to turning on the ground and the student may have seemed to understand quite well, when in the air the student will probably have problems remembering these three seemingly simple steps. Also, he will not be able to give the correct amount of aileron and elevator to make good turns. For these reasons, the instructor will probably have to talk him through his first few turns. The instructor should not be afraid to talk to the student while he flies but he must be careful to stick to the point so as not to distract the student. This is an example of a typical conversation that an instructor would have with his student during his first few turning attempts. It typifies the kind of instructions that would be given to a student. At this point, the plane has been set up for a gradual left turn then the trainer button is pressed to give the student control of the plane. "OK. I have set the trainer up to make a nice gentle left turn. Give a little left aileron to get the turn started and be ready to bring in up elevator. Watch that left wingtip drop. That's it. Not too much now or you'll have to give some right. That's it. You'll need some up elevator now. You waited just a little too long to bring in the up. See that nose drop a bit. Hold the turn with the up. The nose is still dropping. You need more up. That's it. Hold the turn until you're heading back toward those trees. Good. Remember, you're turning left. Be ready to straighten with right. OK. Begin to straighten. Not too much now or you'll over-control. Good. Now let's try a right turn..." The instructor must be careful with how much talking he does. He must stick to the main points of the step. In this case, bank with aileron, hold the turn with up, and straighten with opposite aileron. Some instructors have a tendency to say too much. They may notice the student doing something that may be causing problems for a future maneuver and cannot resist the urge to talk about it while the student is flying. These discussions that are not directly related to the subject at hand should be saved until the plane is on the ground. After each flight, the instructor should review the flight with the student. He should stress those areas where progress has been made and to offer praise. For those problem areas, the instructor now has the student's full attention and can offer advice and constructive criticism. While it is good to talk to help the student get comfortable with a new flying technique, the instructor should ensure that the student is not just following the instructions and confirm that the student truly understands the maneuver the instructor is teaching. When he is following the instructions and performing turns well, the instructor should refrain from giving instructions for a while and just watch him fly. If he continues to do well, he truly understands the maneuver the instructor has been teaching. If the student is having problems making turns, as some will, the instructor can concentrate on each step independently. He can begin by making sure the student can give the correct amount of aileron control to get the desired bank angle. Beginners have the tendency to give too much control, rolling the plane to a very severe bank angle. The instructor will probably have to keep stressing how little stick control he needs to give to achieve the proper bank. The instructor should make sure that the student understands the relationship of bank angle to the plane's tendency to lose altitude; the higher the bank angle, the more the tendency to lose altitude quickly. Once the student can set the correct bank angle, he should then practice maintaining the turn with the elevator. The instructor should make sure that the student is making gradual, level turns, neither gaining nor losing altitude, though gaining is always better than losing. He should stress the relationship of the bank angle to elevator input; the more severe the bank angle, the more up elevator required to hold altitude and the tighter the turn. He should also stress that it is important to begin giving up elevator as soon as he sees the wingtip begin to drop to the desired bank angle. Beginners tend to wait too long, and the plane loses altitude before entering the turn. This is somewhat difficult to master, because if he pull in up too early, the plane simply climbs, eventually stalling. This problem is known as "wishing the plane around with the up". Beginners also have a tendency to forget which way is up. The elevator stick may seem backwards to a person who has never been exposed to any form of flying. The instructor can stress that it is just like a full-scale aircraft; pulling back on the stick makes the plane go up. If the student holds the transmitter more horizontally, it may help him remember this. As the student progresses further in this phase, the instructor should stress the importance of maintaining the bank angle with aileron control throughout the turn, especially if he is flying a very self-correcting trainer plane with a flat bottom wing and a lot of dihedral. The student should practice this by making full 360-degree turns, flying the plane in a full gradual circle. Even a plane that is not very self-correcting will require minor adjustments of aileron to maintain the correct bank angle. Once he masters the 360-degree turn in one direction, then he should practice it in the other direction. When he can perform one 360-degree turn, he should then continue the turn several times, making several 360-degree turns consecutively. This practice forces the beginner to maintain a gradual turn for a long period of time. Finally, the instructor should have the student concentrate on exiting the turn by applying opposite aileron until the plane is flying level again. The most common problem here is that the beginner forgets which way the plane is turning and they attempt to straighten by applying the wrong aileron direction to exit. This, of course, forces the plane into an even sharper turn. The instructor must be prepared for this mistake every time the beginner ends a turn. The lower the airplane is, the more important it is that the instructor be ready. There are several things the instructor can do to help the student with this problem. One way that many experienced pilots do not like is to have the student physically turn with the plane. If he is facing the same direction as the airplane, it will be easier to determine which way to exit the turn. Another way is to have the student keep saying out loud which way he is turning throughout the turn. He will then know which way to exit the turn. Another common problem for beginners exiting turns is they continue to hold the up elevator too long. This of course, will make the airplane climb at the end of the turn and possibly cause a stall. He must practice until he can exit the turn at the same attitude as the turn was entered. Beginners tend to turn much to severely. They bank hard, pull in a lot of up, and level out quickly. While their turns may look fine, the instructor must force them to turn gradually. When they perform such radical turns, it is difficult if not impossible for them to recover on a predictable heading, which will be very important in the next phase of training. If the beginner is having problems, it does not hurt to point out that turning gradually is the more difficult way but they must master gradual turns. When they do, they can look forward to learning the split-S and Immelman turns, which are much easier turns to perform. From the beginning the instructor should force the student to practice left and right turns equally. With no intervention from the instructor, most students will fall into the habit of making turns in only one direction, usually to the left. Most beginners find it more difficult to make right turns. They may complain that the wingtip drops more quickly and more severely when making right turns. They also complain that the plane tends to fall further into the turn while holding the turn with up elevator. This is related to how much engine thrust the plane has. Though some of this tendency can be removed by reducing right thrust, it offers an opportunity to stress how small corrections must be made with ailerons during each turn. Though not very common anymore, there are trainers that have only rudder, elevator, and throttle. These planes fly very much like planes with ailerons. As rudder is applied, the wingtip will still drop. The pilot still holds the turn with up elevator and he still exits by applying the opposite control. The pilot will notice, however, that the nose of rudder controlled airplanes tend to drop more severely in turns than those with aileron control. If the student has a rudder controlled trainer, the instructor must have experience with this type of trainer before he tries to help someone for the first time. It requires a different approach and takes some practice. Most model airplanes are overpowered, including trainers. This means the student will usually not need full throttle to keep the plane in the air. Planes tend to be much more responsive at full throttle. For most practice flying, the throttle will be maintained at a setting that ensures docile performance. As the student progresses, he should be able to handle the airplane at any throttle setting. Ideally, the wind should be calm during the beginners first few flights. However, he should not be considered competent with this first phase until he has flown in wind of at least five miles per hour. He will find that wind presents its own problems to turning smoothly. It will appear that the plane will be sluggish when turning into the wind, while quite responsive when turning in a direction with the wind. This of course, means that different stick control amounts will be necessary with every turn. The best advice is to tell the beginner to fly what he sees. If he gives a little aileron control and the plane does not respond immediately, he will simply have to apply more. Getting the student accustomed to this idea early is very helpful. When he starts slowing the airplane down for landing practice, the tendency for response to become sluggish will be compounded. Most trainers have the tendency to climb with speed, especially trainers with a flat bottom wing design. The faster they go, the more they climb. While this tendency can be overcome to a certain extent with engine downthrust, engine speed is only one factor that influences the plane's speed. As a beginner makes his first few turns, it is likely that the plane will lose altitude and gain speed. When he exits the turn, the plane will have the natural tendency to climb due to the increased speed. This tendency is known as "ballooning". The instructor should be able to explain this tendency. To avoid it, the beginner must make level turns. If the plane does not lose altitude in a turn, it will not pick up speed and it will not climb at the completion of the turn. There is also a tendency for ballooning whenever the airplane is turned into a high wind. To the airplane, it is just as if the airspeed increased by the wind speed. The plane will tend to rise. This can be corrected to some extent by applying down elevator as the plane turns into the wind. The student should get too bogged down with trying to overcome ballooning. Though it may seem like the plane is doing something wrong, it is just a natural tendency for trainer planes. Students and instructor) waste entire flying sessions adding downthrust to the engine and shims under the back of the wing in attempts to keep the plane from ballooning. While some marginal improvements may be made, in the end, the plane will still balloon when it picks up speed. It is much more important that the student concentrate on practicing to make level turns. The student should accept this fact. His next airplane probably will not have this tendency. One signal that the student is getting close to the completion of this phase is that he begins to complain that the airplane always seems to climb. This means he has overcome his tendency to lose altitude in every turn. Now it will be a relatively simple matter of flattening out his turns. He can bank slightly more severely with the aileron or not give quite as much up elevator to hold the turn. When the student can keep the airplane in the air for a whole flight with no coaching from the instructor, he has mastered this phase. However, he must be able to turn left and right equally well. It is quite common for a beginner to become much more comfortable with one direction or the other, and ends up constantly setting up the plane to turn in the comfortable direction. IV. Teaching How To Set And Hold HeadingsThe objective of this phase is to get the student to the point where he can fly the plane under complete control at all times. If the student has truly mastered the first phase of flight training, this phase should be relatively easy to master. The instructor can begin stressing the importance of being able to set and hold headings even during phase one. As he begins to make level turns, it should be stressed to the student how important it is to recover from the turn in a predictable direction. This will be very important during the setup and final approach for landing. Setting a headings means that the student must be able to exit each turn in a predictable manner. Holding a heading means that the student must be able to keep the plane flying in the headed direction for as long a period as required. Again, at the completion of phase one, the beginner may be able to keep the plane in the air but the plane may be flying the pilot to some extent. The beginner may still be reacting to the airplane instead of making the airplane react to stick movements. The instructor should explain that the key to setting precise heading is knowing when to begin exiting the turn with the opposite aileron. The smoother and more gradual the turn the easier this will be. The point at which opposite aileron must be applied depends on the severity of the turn; the more gradual the turn, the sooner the opposite aileron is applied and the easier it is to smoothly exit the turn on the desired heading. As mentioned in phase one, beginners tend to turn much too severely, making it very difficult to exit turns precisely. The student should practice making turns in both directions by flying figure eight patterns. Since it is easier to make turns in a direction away from the pilot, he should start by making left turns on his right and right turns on his left. The instructor should stress the importance of flying much more precisely. Since flying fields are rectangular in shape, each corner of the field can be used as the target heading for each turn. The student is told to maintain each turn until the desired heading is reached. He is exit the turn pointing directly toward the corner, and then hold the heading for a short period of time. While the first few attempts will not be perfect, this practice forces the beginner to think about exiting the turn very early in the turning process. The first goal will be to exit each turn with the plane pointing directly into a corner. When the student has mastered turning left on the right side and right on the left side, he will then reverse the direction of the figure eight. This forces him to make more difficult turns. Since the student must keep from flying over the pits, turns must be made in a timely manner. This tends to put a little more pressure on the student. Figure eight maneuvers are excellent for practicing setting the heading because the instructor can easily monitor the student's progress. He will be able to tell if the student is catching on or still having problems. As long as the student has truly mastered phase one and can consistently make smooth level turns, the two most common problems a beginner has at this stage are exiting too early and exiting too late. If exiting too early, the student must turn again to eventually get the heading he wants. If exiting too late, the student will overshoot the desired heading and have to turn back. Both of these problems lead to over controlling the airplane. Talking the student through the first few turns can help with each of these problems. If he has either of these two problems, the instructor should stress the importance of being able to begin exiting the turn slightly before the desired heading is reached. The more gradual the turn, the easier exiting should be. This is the reason that the instructor should keep the student from turning too radically during the first phase. When the student has mastered flying figure eights in both directions, he can then start to free form turns. Based on the position of the airplane at a given time, the instructor can call the turn the is to be made. This practice forces the beginner to fly the plane in new and different attitudes, and commonly turns up trouble spots like attitudes and positions in the sky with which the student is not yet comfortable. Everyone had trouble spots as they began flying. For these trouble spots, the student needs practice. At the completion of this practice, the beginner should be able to control the plane in almost any position in the sky. At this point in the training, the student should begin thinking about trim settings. He should have almost mastered the ability to keep the plane in the air when the plane is perfectly trimmed. It is a good time for the student to practice with an out-of-trim airplane. The instructor can reach over and move the aileron or elevator trim slightly off center on the slave transmitter. The beginner will be forced to determine what is wrong and correct the trim problem. When this is started, it can be repeated on the first flight of each practice session. After the student has mastered figure eights and free form turns, the instructor must stress the importance of being able to hold a precise heading. Even the most stable airplanes tend to wander from set headings based on wind direction and velocity. The student must be able to keep the plane going in a given direction. This must be mastered before he will be able to land. During the final approach, the student must be able to hold the plane right on the middle of the runway all the way to the ground. For practice, the student begins with a figure eight but this time the instructor should have the student extend the straight legs of the figure eight, forcing him to hold the heading for at least 100' at the completion of each turn. He must practice making minor corrections as the plane tends to wander from its desired heading. The direction and amount of wandering will vary almost every time based on wind speed, wind direction, and the planes attitude at the completion of the previous turn. The student must always be ready to apply minor corrections in order to hold headings. The eventual goal of this practice is to make perfectly shaped figure eights with the crossover right in the middle of the flying field. Once he has mastered this maneuver, the student can truly fly the airplane with a great deal of precision. Once the student can fly the extended figure eights with precision in both directions, the instructor can start him flying a pattern that takes the trainer down the center of the runway, still maintaining a safe altitude. One way this can be done is have the student fly a long oval with the near side of the oval right over the runway. He should practice holding the heading on the runway for the entire length of the flying field. As in other practice sessions, he will reverse the direction of the oval in order to have practice equally between left and right patterns. Most of the practice to this point has been at one throttle setting. As stated during phase one, most students find it easier to fly with a throttle setting that is just strong enough to keep the plane in the air, resulting in a docile flying airplane. However, before progressing to phase three, the student should fly the plane at different throttle settings. When he decreases the throttle, the plane will become less responsive, simulating how a slightly underpowered plane will respond just after take off. As the throttle is increased, the plane becomes more responsive, simulating how an over-powered plane will behave during take off. If the instructor wants to teach rudder coordinated turns, this is the time that it should be done. He should explain that the rudder can be used with the ailerons and elevator to control a turn. It may help to demonstrate this by performing a knifeedge maneuver with a sport airplane. In the knife edge, while the plane is banked ninety degrees, the rudder control does affect the plane as the elevator normally does. As the student gives aileron and the plane banks, opposite rudder can be given to counteract the natural tendency for the nose of the plane to drop. Keep in mind that most trainers will turn quite nicely without rudder control. In fact, the influence of rudder may make it quite difficult for the student to master turning. He may not even notice any difference if the rudder control surface is small. For this reason, I usually rudder coordinated turns are usually omitted from basic flight training. When the student has mastered the ability to fly the plane under complete control at all times, when he can fly the airplane in virtually any attitude, when he has gotten all of the left/right, up/down mistakes under control and when he can set and hold headings, flying with precision, then and only then is he ready to progress to phase three of the training program. V. Teaching How To Take OffThe objective of this phase is to teach the student to taxi and take off. Up to this point, it is relatively easy, though sometimes disconcerting, to train students without a trainer system. As long as the student keeps the plane relatively high, the instructor can easily grab the transmitter out of the his hands when he gets into trouble and still has time to recover the airplane. However, as the student begins practicing take-offs and landings, the plane will be very close to the ground and there will be nothing the instructor can do to save the plane if he gets into trouble. It must be very clear to students who do not have trainer systems that if training is to proceed, it will be at the risk of the student. New instructors are advised discontinue training without a trainer system. Before the instructor turns the plane over to the student to take off, he must be certain that the plane is tracking straight. After every hard landing from, he should check the tracking before the next takeoff attempt. In the hands of an inexperienced pilot, a plane that is not tracking properly can be very dangerous especially if the plane veers toward the pits. The student can set the tracking at home letting the plane roll down a shallow grade with the radio turned on. Most driveways are graded to drain water from the house and are perfect for this. With the rudder stick at the neutral position, the plane is allowed to roll down the grade and watch for tendencies to veer in either direction. The student must not adjust the tracking using the rudder trim because this will affect flight trim. Adjustments must be made mechanically within the airplane. The surface of the local flying field has a great deal to do with how difficult it is to taxi. Taxiing on hard surfaces can be more difficult since the plane move too fast. A grass taxiway tends to slow the plane down and requires more power. Unfortunately, the instructor does not have control of the runway surface, meaning the student will have to get accustomed to the available. Taxiing and take-off departure can be quite difficult to master, especially if the local field has restrictions about take-off directions. If the wind is not in the direction of the runway, take-offs and landings must be made in a crosswind condition. Some clubs do not allow the pilot to walk out on the runway to make a take-off, meaning that all pilots must stand at designated pilot stations. If the local field has such restrictions, it will take the student longer to fully master take-offs. Depending on the size of the local flying field, taxi practice may be discouraged. At many fields, nobody can take off and land while a student practices taxiing. This means the student may have to practice at odd hours when there are no other modelers around. Fortunately, after the instructor gives the student a few pointers, he should be able to practice taxiing by himself. If a beginner has a 4 - channel radio system with rudder and steering on the left stick, he will probably find it awkward to precisely use his left hand. He will also find it difficult to control throttle and rudder independently. He can begin by getting comfortable with the left stick without the engine running. Once the student can move one control without moving the other, the instructor should explain the plane's ground handling characteristics. The instructor should been doing a lot of taxing with the trainer to this point and while different airplanes can have dramatically different ground handling characterists, the instructor should be able to help him understand how responsive their plane will be on the ground. The instructor should explain the plane's natural tendency to accelerate quickly as soon as it begins moving. Many students slowly increase the throttle to the point where the plane begins moving and do not realize the plane will continue accelerating until the throttle is reduced. Students should be taught to quickly apply throttle to about half way and back to idle in short quick bursts. This way they can get the plane moving slowly and stop any time the plane gets moving too quickly. As they develop a feel for what it takes to get the plane moving, they will make the plane move smoother. First and foremost, the student must keep the plane moving slowly. The instructor should be ready to take control should the plane start moving too quickly. It will take quite a bit of practice for the student to become comfortable with steering since it must be done with the left hand. Also, the same left/right orientation problem that everyone has when learning to fly also occurs when learning to taxi. After the student can handle the plane well on the ground he should be instructed to head the plane into the wind to practice high-speed takeoff runs. He should not be allowed to take off quite yet. As soon as the plane builds up speed, he will retard the throttle. He should realize how little rudder it takes to make the plane respond at high ground speeds. Students have a tendency to over-control with rudder during the early stages so the instructor must be ready to take control at all times. At this point, the student should be quite comfortable with handling the plane on the ground but the instructor will still need to make it as easy as possible for the first few take-off attempts. He can explain that taking off is just a matter of building up flying speed while heading into the wind. Once flying speed is reached, the student must apply just a small amount of up elevator, though some well- trimmed planes may actually lift off by themselves. Once the plane leaves the ground, the nose will be pointed up slightly and he can release the up elevator. If the plane is properly trimmed, the plane will continue its gradual climb at full throttle until it reaches a comfortable altitude and can be turned. As the plane rises, he must be ready to make minor corrections to hold the plane's heading directly into the wind and to maintain a gradual ascent. The first turn should always be made away from the pit area. When the plane has reached a safe altitude, the throttle can be reduced. Students tend to be so nervous after their first few take-offs that they forget to reduce the throttle. The instructor should demonstrate taking off prior to having them do it emphasizing each aspect of the take-off. If the rules do not prohibit it, the instructor should position the student so that he can take off in a direction directly away from his position. They walk to the middle of the field if necessary. Later, the student will have to learn how to take the plane off in different directions while standing at the pilot's station. As he increases the throttle for take-off, the instructor must match the throttle setting to that of the slave so that he can take control in the event of a problem. Students have problems in three (3) areas. First, they have problems holding the plane on the proper heading with the rudder while it is on the ground. It can be very dangerous if the plane wanders off in the direction of the pits. The student should be aware that starting the take-off roll does not mean he must take off. If anything goes wrong or he is uncomfortable for any reason, the student can abort the take-off. This is why the high-speed practice runs are so very important. During these runs, the student does not expect to take off and will be cutting the throttle every time. With this experience, they will be much more likely to cut the throttle at the first signs of problems during actual take-off runs. Second, when taking off in winds over about 2-3 mph and especially with a cross wind, students have trouble holding the wings level after the plane lifts off. Since the plane is not moving very fast at this point, it may respond rather sluggishly. The student must be ready with firm, accurate aileron control. When taking off in any kind of cross wind, the student must predict which way the wind will tend to blow the plane as it lifts off. This way, he will be ready to apply the opposite aileron. Third, students tend to apply too much up elevator to get the plane off the ground or they hold the elevator too long. Either way, the plane will have the tendency to stall soon after liftoff. Many students think that they have mastered take-offs with their first successful one, regardless of how scary it was. However, the instructor must stress that each take-off will be different, and it will take many take-offs to become fully proficient. Wind direction, wind speed, and rudder sensitivity will result in a few nerve-wracking moments. As soon as the student has successfully taken off, the instructor should take control, land the plane, and make the student repeat the take-off again and again. If all practice is done on a nice calm day, the instructor must be with him the first few times he takes off on windy days. When the instructor is confident that the student is in complete control on the ground, when the instructor has seen him make a mistake and is confident that he knows enough to reduce the throttle, when he can repeat the take-off roll repeatedly regardless of wind conditions, when he can maintain the take-off heading in a gradual climb repeatedly, then he is ready to progress to the fourth and final phase. VI. Teaching How To LandThe objective of this phase is to get the student to the point where he can make consistent approaches from both direction and land. This phase requires a great deal of throttle manipulation. Before starting this phase, the instructor should confirm that the student's engine will maintain idle, advance from idle to full, and in general, perform without stopping or stuttering at all throttle settings. If all phases to this point have been truly mastered, landing will simply be an extension of what the student already knows. However, if he is having problems with this phase, it should be taken as a signal that further practice is needed. Before the student can begin learning how to land, he must understand how the plane responds at slower speeds. With the plane at a safe altitude, the instructor should have the student reduce the throttle to just above idle and fly the figure eight pattern. He should be made aware how the ailerons respond more sluggishly and how the plane loses altitude especially in turns. He must also be aware that if he tries to maintain altitude by applying more up elevator, the plane will eventually stall. Most trainers are very stable in a stall so no radical controls will be required to recover. As he continues to lose altitude in his figure eight pattern, eventually he will have to apply more throttle to regain altitude. This should be repeated several times. He must be able to maintain control even at slow speeds, especially holding a heading into the wind. In phase two, the student was taught to fly with precision. He was made to fly down the middle of the runway in an oval pattern. The goal was to hold the heading all the way from one end of the field to the other. Now, he will repeat this practice but at reduced throttle. As before, he must be able to the heading for the length of the field at idle. He will increase the throttle at the end of each pass. He will practice this from each direction. During the actual approach, the student must begin letting the plane come closer to the ground. The student is normally taught a symmetrical approach pattern; i.e., the same basic pattern is used from either side of the field. This also makes it quite easy to practice from both directions. A modified figure eight pattern is used for teaching approaches. Starting with the plane flying down the middle of the field from right to left, the student will veer off to the right at about 45 degrees shortly after the plane passes. He will hold this heading until the plane has made sufficient room to make a left final approach turn. The student will then begin a long sweeping left turn with the goal being to end the turn with the plane perfectly aligned with the middle of the runway. At this point, he will reduce the throttle to just above idle and hold the heading until the plane passes. The student then increases the throttle and veers of to the left at about 45 degrees. The heading is held until enough room is made for a right approach turn. The student will then begin the long sweeping right turn to line up with the middle of the runway. This is repeated over and over again. As the student gains proficiency, the throttle is cut earlier and the plane is allowed to come closer to the ground. While all of this may sound a little difficult, if the student has truly mastered setting and holding headings, this is actually rather easy. All that is added at this stage is the increase and decrease of the throttle. This is rather difficult to explain to students but he must understand that the nose of the plane must maintain a slightly downward attitude throughout the final approach turn. This is how airspeed is maintained as the plane gets closer to the ground. The windier it is, the more important this point becomes. While some pilots try to counteract the wind with higher throttle settings, the decent of the airplane allows much finer control of airspeed than throttle. If the nose of the plane balloons at the end of the final approach turn, the plane will eventually stall. It will be impossible to maintain airspeed, and if very close to the ground, could result in disaster. As the student is practicing approaches up high, he must pay particular attention to the nose of the airplane. Once the student has progressed to the point where that he can consistently align the plane with the runway and bring the plane to within twenty to thirty feet from the ground, he is are finally ready to land. Students tend to rush this step so the instructor must determine when he is ready. A little more practice than necessary will not hurt. The throttle setting of the master transmitter must be matched to that of the slave transmitter so that he will be ready to take over at any moment. Before letting the student to actually land the plane, the instructor should explain that landing is nothing more than letting the airplane drift to the ground. The student should understand that he does not have to force the plane down with the elevator. It will descend naturally because of the low throttle setting resulting in reduced lift. During the last twenty to thirty foot of descent, the student must keep the wings level. As with taking off, he must be ready to make sharp, precise corrections to keep the plane on the center of the runway. Again, the natural tendency of the plane at idle will be to descend, so if the proper heading is maintained, it is a relatively simple matter of waiting until the plane comes to the ground. When the plane drifts down to within about 1-2 feet above the ground, he should gently pull back on the up elevator to cause the plane to flare. The instructor should demonstrate the landing procedure prior to having the student do it. Normally, a student's first few landings tend to be a little rough. Though the correct amount of approach practice should help him overcome nervousness, landing can be especially unnerving for the student. Most students tend to panic when their model is low. They forget which way to turn, especially if minor aileron corrections are necessary. Though a student's first solo is a great confidence builder, the student must not be allowed to think the he have mastered landing just because he has done it once. As with taking off, every landing will be different. While the student will be very anxious to begin flying by himself at this point, he must practice landings over and over again in different directions and wind conditions. One excellent way to practice take-offs and landings is with touch-and-gos. After landing, without killing the engine, the student will taxi back, take off, and land again. As he gains proficiency, he can apply throttle as soon as the plane touches down, performing a true touch-and-go. It is likely that at some point during training the instructor will have to perform a few dead-stick landings. The student will see how the instructor handles them but he should also practice them since eventually, everyone has to land without power. One obvious way to practice is to simply cut throttle and pretend the engine is no longer running. At first, the plane should be on a nice approach so the student can land with relative ease. As he continues practicing, the instructor can force the plane into more precarious conditions then cut throttle. Even if the instructor just has the student tell him what he would do if the engine died in a given position, it may be good enough just to have the student think about the situation. In any case, be sure the student must be prepared. The whole point of R/C training is to get the student to the point where he no longer needs the instructor's help. If he has successfully completed the four phases outlined, he should be ready to fly alone. He must understand, however, that he is by no means an expert pilots. The practice he has done has been with close supervision. Eventually, there will be no instructor there to take control when things go wrong. The student could still get the plane into rather precarious situations. This knowledge should inspire them to be quite cautious for a while. VII. Other Important Things Students Must KnowThere are several other things that the instructor should relate to the student as he learns to fly. These presentations are made directly to the student, so this information can be copied and distribute to the student. The time spent at the flying field is intended to be fun. Nobody likes going to the field only to be bombarded with a bunch of rules and regulations and of course, no one likes to be yelled at for doing something wrong. Unfortunately, this hobby can be a dangerous one. R/C flyers must all treat the hobby with respect and acknowledge the potential danger. One flyer may think something is safe and acceptable will his actions be totally rejected by other flyers on the flight line. No intelligent flyer will intentionally do something to cause an accident. It is only when one flyer makes an mistake that accidents can occur. While students seem to make the majority of the silliest mistakes, even experienced pilots have been guilty of unwittingly breaking safety related rules. In this section, there are several safety related guidelines. The reasoning behind each rule is given so students can understand why we consider them so important. Mistakes made around the transmitter impound booth can be costly. Many airplanes have gone out-of-control because these simple and basic rules are not followed. And an out-of-control airplane can end up anywhere. As soon as the student arrives at the field, his transmitter should be placed in the impound booth. He should check to see if anyone else is on his frequency at this time. If there is, he should find each flyer and alert him to the fact that he is on the same frequency. This also applies to flyers who arrive later. The transmitter should remain in the impound area while not being used. This serves two (2) purposes. First, the student will be forced to walk over to get his transmitter whenever he wants to fly, keeping him from fiddling with his trainer when he has not pinned the frequency. Second, and more importantly, if someone who is on the same frequency crashes, the student can easily prove that his radio was off at the time of the crash. Together with the suspicious pilot, the student can walk to check the status of his transmitter. On the other hand, if the student stores the transmitter close to his airplane, he can easily be accused having the transmitter on while another pilot was flying. The student's transmitter must never be turned on without pinning the frequency. Before the student is allowed to turn on his transmitter, he must place a pin with his frequency number in the corresponding tube at the transmitter stand. This gives the student control of the frequency and nobody else with the same frequency can turn on his transmitter. All types if objects used as frequency pins. Screwdrivers, pens, pencils, and even broken ailerons have made their way into those little holes. While any object that can be seen from a distance will work to pin the frequency, the best frequency pins include the frequency number in large characters so that everyone can see them from a distance. To help other flyers, the student should also have his frequency number on his transmitter in large enough characters that a person can see it without having to ask. This helps each pilot determine who else is on his frequency. As a courtesy, he student should remove the frequency pin every time he finishes a flying session. He should do this when he returns his transmitter to the impound booth. This keeps other flyers from having to search for pinned frequencies that are not being used. If the student gets in the habit of impounding his transmitter and removing the frequency pin every time he finishes a flight, he will never leave the flying field with the frequency pin. After the student leaves, if the frequency pin is not in the frequency hole, the student will cause other pilots a great deal of problems while they try to figure out who has the frequency pin. As a courtesy to other flyers, every time the student finishes a flight, he should check to make sure that nobody else is waiting for the frequency before he decides to fly again. The student must be very careful whenever he turns his transmitter on. If frequency is pinned and he cannot find the owner of the pin, he should ask everyone in the pit area. Another many possible explanations for his frequency being pinned so every effort must be made to find the frequency pin. While most rules may seem to be nothing more than common sense, the student might be surprised at the how these rules originated and number of pilots who break these rules. Hold on to the plane whenever the engine is running. Never let go of an airplane with its engine running until it is on the flight line and ready for taxi out. Always keep it under complete control and always treat an airplane with the engine running as if the radio is going to fail at any moment. Hold-down devices should be used to ensure that the airplane cannot move until the pilot is ready to carry it out to the flight line. Never taxi in the pit area. When the student is ready to take his airplane to the flight line, he should carry it, not taxi to the flight line. After landing, he should carry the airplane back to the pit area. Never stand in line with the propeller of a running engine. A propeller rotating at 10,000 to 20,000 RPM carries a great deal of centrifugal force. The most dangerous position to be in near a running engine is directly in line with the prop. A piece of dirt attached to the prop during a hard landing will usually be thrown from the prop or if the propeller is fractured in any way, an injury could occur if the propeller shatters. Once the engine is started, always stand behind the airplane. Needle valve adjustments should be made from behind the airplane. Once the student's engine is running, adjustments to the needle valve from a convenient and safe position. From behind the airplane, the student can easily hold the plane one hand while he adjusts the needle valve with the other. Use a glove, chicken stick, or electric starter to start the engine. Extra caution must be exercised when starting the engine. A flooded engine can really if the student uses his bare finger to start it. As a courtesy to other pilots, never break in an engine in the pit area. If the student must perform the break-in procedure at the flying field, he should move to the end of the pits. From there, the noise will not be excessive. These rules apply from the time the student enters the flight line until the time he carries his airplane back to the pit area. There are priorities in flying based on the basic rights of way for the flying field in the order of most importance.
Students need to keep trying new things in order to improve. However, all flyers must fly within their abilities, especially when the field is crowded. He should save new maneuvers for a day when the field is less populated, or get an instructor to help. The more a student can keep other pilots informed, the safer he will be. For instance, if another pilot calls a landing without the student hearing it then the student calls a landing loudly, another pilot may alert the student that someone else has already called a landing. The student must know which way everyone is taking off and landing. Especially on calm days, pilots have a tendency to take off in all directions. The student should watch to be sure the he knows which way everyone is taking off and landing. If in doubt, he should ask. If the student needs help, he should not attempt to fly by himself. Students have a tendency to prematurely think their ready to fly by themselves. The student may have made one or two solo flights and may be feeling confident. He must never fly by himself without the approval of his instructor. He must be aware that his airplane is not the only thing at risk. When in doubt, the student should ask for help. No matter what the rule, if the student does not understand what he, he should ask an experienced flyer for help. The remainder of this discussion will give the most basic considerations when making adjustments on a new engine. While there are many potential problems that can cause similar symptoms, and while each flyer has his own way of doing things, this should acquaint the student with proven ways of handling the most common problems he will face. Nothing is more frustrating than trying to learn how to fly with a poorly performing engine. The student cannot get much quality stick time if his engine is constantly quitting in the air. When the student eventually begins setting up for landings, it will be mandatory that the engine responds properly. If the engine dies close to the ground, the results can be disastrous. The biggest cause of a poor running engine has to do with how the fuel tank is mounted in the airplane. As the instructions that come with the airplane and engine say, the fuel tank must be mounted at the same level as the engine's drive shaft. Ideally, the middle of the fuel tank will be in line with the drive shaft when viewed from the side. If there must be a variance, the fuel tank should be mounted on the high side of center. If mounted too low, the engine will have problems drawing the fuel into the carburetor and will tend to run lean. However, if mounted too high, this same problem will exist when he later attempts inverted flight. Kinks in the fuel line must be eliminated. Any kink or sharp bend will limit fuel flow. The student must drill the fuel line holes in the firewall large enough for the fuel lines. If he has to force the fuel line through the hole, the hole is not big enough. He must be sure the clunk line extends to the bottom of the tank without closing off the clunk. If the line is too long, the clunk hole may be pressed against the back of the tank. The fuel line and muffler line must be kept as short as possible so as not to impede fuel flow. New engines are notorious for burning glow plugs quickly. This is primarily because new engines are commonly run quite rich to ensure a good break-in. However, as the student begins leaning out the new engine to gain performance, the glow plug problems should go away. If they do not, the student should check the head bolts. Loose head bolts will cause also cause premature failure of a glow plug. The carburetor must be connected to the engine so that no air can leak from the bottom of the carburetor seal. If the student removes the carburetor for cleaning, he must be sure to seal the bottom properly before tightening. Most carburetors have a rubber seal that must be compressed before the carburetor hold down screws can be tightened. In the same way, the crankcase bolts must also be tight, as must be the engine mounting screws. No matter what the engine manufacturer suggests, it is always best to break in a new engine. Breaking in will ensure that internal engine parts wear into position properly, while not under a great deal of load. While the student can break in a new engine while it is mounted to his airplane, many pilots like to perform the break in procedure on a test stand. Either way, the engine should be kept running very rich during the first steps of the break-in procedure. At full throttle, the needle valve should be well open to ensure that the engine never comes close to peaking out. As the fuel tank gets close to empty, the student should be ready to stop the engine to keep it from leaning out. Two (2) to three (3) tanks of fuel should be run through the engine in this manner. The second step to breaking in a new engine is to begin leaning it out. The engine is started and the high-end needle valve is turned in. As this is done, the engine will begin to accelerate. It should not be allowed to peak yet but to run faster, a little at a time. The student should start manipulating the throttle to let the engine run at various throttle settings for 10-20 seconds at a time. With the engine running, the student should continue turning the needle valve in until the engine peaks. To determine when it has peaked, he can lightly squeeze the fuel line. If the engine accelerates more, he can adjust the needle valve in a little more then Squeeze the fuel line again. He will continue this until the engine has peaked then back off about two to three clicks of the needle valve making it slightly richer. Any engine will have the tendency run leaner in the air. Backing off a little on the ground will keep the engine from becoming too lean in the air. Most high performance model airplane engines have two (2) needle valves. The needle valve that has been mentioned is the high-end needle valve. This needle valve controls the high throttle setting and functions basically the same for all model airplane engines. Turning it in leans the engine and turning it out richens the engine. The low-end needle valve may vary from one engine to the next. For most ABC style engines, like the OS 46-SF, the low end needle valve functions the same as the high-end needle valve. Turning it in leans the low end and turning it out richens the low end. Certain carburetor configurations are the opposite. The FP series of the OS engines is one example. Before the student can adjust his engine's low end, he must know which way the needle valve must be turned to achieve the desired results. The owner's manual for the engine will give this information. As with the high-end needle valve, the student begins peaking out the low-end from the rich side. With the low-end needle valve wide open, he should set the engine to its idle position with the glow plug battery disconnected. The idle position should be set so that the carburetor is open to about 5-10 percent of maximum. If the engine dies, the low-end needle valve should be turned in about 1/4 turn and the engine started again. When the engine runs smoothly at idle, the throttle is advanced quickly. At this point, the engine will probably sputter but reach its maximum speed. This indicates that the low-end needle valve setting is still too rich. The low-end needle valve should be turned in by about 1/8 of a turn and the throttle advance again. If the student should goes too far, and the engine's low end needle valve setting is too lean, the engine will bog down and possibly die when he tries to advance the throttle. The student may be fooled at this point. Since an engine consumes fuel at a very slow rate when at idle, the engine may be under the influence of the last idle adjustment as the student increases the throttle. The throttle should be advanced and reduced several times to confirm the setting. If in question, the fuel line can be squeezed slightly to force the engine to use up the residue fuel. Eventually, by repeating the above procedure, the engine will respond quickly and accurately to the every throttle command. Though the techniques given in this article should handle 90% of all engine problems, there are possible problems that affect an engine's performance that have nothing to do with tuning. If the student finds that no matter what he does, he cannot get the engine to run properly, he should ask for help. One of the experienced flyers in the pit area will be more than willing to help the student. Additional Information:
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