So, you want to learn to fly by radio control. This is how you begin:

Transcription

1 So, you want to learn to fly by radio control. This is how you begin: By Carl Murphy I often put a radio controlled airplane a hundred yards in the air trimmed for a slight climb, give somebody the transmitter and leave. What should I do? Just fly the thing! And if it crashes? Go and get it, I ll be back in five minutes With an expensive airplane where fifty hours of assembly were at stake that would be unthinkable. With a Foamie that is difficult to ruin and easily replaced in a few hours it is downright entertaining. Beginners often first develop self confidence when they have no other choice. I was the champion of my club at flying inexpensively, and still enjoying it. Over and over other pilots have come to me to thank me for helping them learn to fly, It wasn t usually their first flights, but rather in the phase where they had learned how fast things can go wrong and didn t trust themselves to fly alone. In comparison with my other hobbies I don t have to worry about hypothermia, game wardens, hearing damage, being broken up, getting run over, hangovers, getting back across the boarder, veterinarian bills or jealous husbands. After flying airplanes by radio control for fifteen years now, about a hundred different airplanes, (the majority of them simple and inexpensive, all gliders or electric powered, including 48 flying wings) and regularly teaching new pilots; I have some specific recommendations. But, there are others with just as much experience and success, their choice of methods and materials is different and they would probably classify me a fool for what follows. As usual when that happens it demonstrates that there are other factors involved, or maybe what they thought was important, isn t. There is nobody that spends as much time in the air with less time spent building or cash outlay. I often fly at locations that are not landable. Or I check if the conditions are suitable for slope soaring. Or I investigate how the wind aloft is. Often the other pilots, with their expensive and fragile airplanes are prisoners on the ground while I play with the unseeable opponent. I, the shame of the club, often fly the worst looking airplanes, and I am proud of it. Flying is only learned by flying, the scares from the repairs are the evidence for it. Long ago when I learned electronics, the best introductory book began with what was actually the most complicated first and went backwards to the details from there, so does this set of instructions. Try reading all the way through first, and then again, there is more to it then can be understood quickly. There are plenty of books for beginners already, but they can t risk being specific. Since this is just for my friends and club member here is what the other books left out and some of what a publisher wouldn t dare to print. For those of you that have questions: The airplane itself, that is so enticing in the store, is, measured in purchase price, the cheapest part of the whole thing. Traditionally youngsters after countless hours had created something, that after the first, all to short, flight attempt was just a pile of wreckage. Now, many years later they see me flying and it occurs to them, hey, that is possible! It is for those of you, that 1

2 so often have asked me about flying that I wrote this booklet for. There are already plenty of books for beginners. Here are my personal conditions for learning to fly. What you should I learn on: The era where home-builts were rewarding, at least for beginners, is past. You must not fall in love with your first couple of airplanes. The first planes should be purpose machines that exist for learning to fly. I recommend foam airplanes that are nearly completely built and have the motor in back. The motor in back because with every bump, and there are going to be lots of them while learning, the plane lands on its nose. When the power-plant is in front the whole thing, including all enthusiasm, gets wrecked. The previous cannot be overemphasized. No matter how unconventional a foam airplane with the motor in back at first appears, it is the best way to learn to fly. Having the motor pushing has disadvantages: The noise from the propeller is a lot louder, the propeller has a lower efficiency, and it looks odd. We want foam because it is simple and quick to build with and can absorb an incredible amount of impact. They can now cast in foam a better airplane then you could build yourself. If you invest less of yourself by spending intensive hours building you are much more able to concentrate on actually flying. As soon as you are soaring overhead while the others are on the ground making repairs, how the airplane looks ceases to matter. The most common I can t get it reason is too little time in the air followed by too many hours spent fixing. What it costs: When it comes to money there can be big differences, but there are guide lines. If you want to get going with a minimal outlay and buy everything new about (500) dollars, and a few more hundreds after that. It sounds like a lot, but some of the equipment lasts for years. If you really want to learn how to fly don t try it for less then five hundred bucks. If you have somebody helping you and get some of the equipment used maybe a couple of hundred less would do. But, with the simple new all inclusive sets that start at (130) dollars even we, who already know how to fly, have difficulties taming them. The satisfaction is not measured in the money you spent, but you need to spend enough that the equipment actually reliably works. When I am piloting a remote controlled airplane I am freed from the ordinary, without the expense or danger of siting in it myself. 1 Flying is a complete experience that is not measured just in money or time in the air. As a beginner, if you have help, you may expect about 50 flights from your first airplane. I have had flying wings that made 750 flights (even if the equipment then limited the powered 1 See the follow on section about man carrying airplanes. 2

3 portion of the flights to 4 minutes), but two, that were blown away by the wind, didn t even withstand their first flight. It always happens, you find yourself in a hobby store and just have to have something that isn t planned for. Airplanes that should have been your fourth one, or motors that just look so cool ectera. It doesn t matter what your age when you enter the hobby, if you find yourself in a model store it s going to happen. The time required varies. And you should have insurance. It is possible to get started alone, but only for special people, and even then it isn t recommended. It used to be that we experienced small aircraft builders were pleased when the construction of an airplane was completed in three to five working days. With balsa I expected three to five times as long for repairs as building as it took to originally build the airframe. The airplanes were continuously damaged. With flights that, on the average, lasted up to twenty minutes, it took about a hundred flights to get a one to one building to flight time ratio. Which only few (very few) airplanes withstood. A prebuilt foam airplane, after you have some practice, is ready after two to eight hours. Verifying that the radio and equipment is functioning correctly takes about as long as the gluing together. If flights last twenty minutes, and they may often be longer, the plane in the hands of a capable pilot easily lasts twenty times as long in the air as the building took. The end of a foam airplane is usually the result of either foolishness for a total write off, or material fatigue. The Airplane: The Easy Star from the Multiplex company. Simple and fast to build, easy to fly, not easily damaged and then usually with a minimal expenditure to get it back into the air. It looks like nothing you would ever see at a man carrying airport. Please, for the first airplane forget the wish that the plane looks like something in which you yourself could sit. No airplane that can carry passengers would ever withstand so many impacts as your first remote controlled must. In principle what we want is not a model but a flying learning device. The Easy Star has, depending on what it is fitted out with, either the from the manufacturer 30 watts (1/25 of a horse power) output, with which it may only be used near sea level on days with no wind, on up to 350 watts, at which the propeller whines and it can almost fly straight up. For beginners 60 to 120 watts output to the propeller seems to be best. Thanks to the motor being above and behind the wing and elapor foam an Easy Star can withstand the impact of a steep dive from ten foot high into the ground and (after straightening, glue and tape) be flow again, any other airplane would be ruined. Sometimes to convince people of the advantages of elapor I stand on a wing. I used to weigh in for competition at 218 pounds, nothing happens. The spinning and flipping on landing, that would otherwise cause so much damage, are mostly just absorbed with no damage by an Easy Star. Even after the airframe is no longer repairable most of the equipment can usually be used again. It can be landed almost anywhere. That with the land almost anywhere is very important, even at the club airfield beginners often land off the runway, way off sometimes. 3

4 Flights with the Easy Stars last from twenty minutes up to hours. To date boredrem (after determining that the mechanical connection of the wings is only effective for about fifty times and has to be improved) and foolishness have set the limit on durability. My four personal Easy Stars lasted the following flights respectively: 215 flights, fourth set of wings separated in the air, 350 flights, wings separated and landed in the ocean, 277 flights, radio receiver quit, I have a photo of the airplane 50 feet up a tree somewhere in the impenetrable scrub forest of the Santa Ana River, 351 flights, a beginner lost orientation at the end of a dive and shredded it by flying through a tree. If you have help you may expect about fifty flights from your first airplane. If you try to go it alone it your first airplane(s) probably won t last long enough to get a whole minute of flying. The Radio Controls: Hitec/Multiplex offers a complete Easy Star package with everything that is needed for flight (even if some of the stuff only barely works) for the affordable price of $190 (plus tax and transmitter batteries). Included is a simple 3 channel FM radio control with two servos, it is entirely adequate. The German version costs Euro 210, that includes a 4 channel FM radio. Any radio must have a full range (at least a thousand yards, few people fly further away then that), the ones for Park Fliers are not for use with the Easy Star. The range of an ordinary radio is much greater then you can see the airplane, at least a mile. If you are buying a new radio separately, get one in Gigahertz (the frequency band of mobile phones) and quit worrying about interference. I like the ones from Spektrum, now everybody seems to offer one. Although my personal recommendation for your first radio is to get the simplest possible, there is a vast array of radios available, most of them require programming. To which I can only recommend, use what the people you are going to fly with know how to get to work. For the Easy Star I recommend servos from Hitek in the size HS 81 with the ordinary plastic gears, or similar. They are exactly the right size and exactly fit the hole made for the servos. It is possible to install smaller servos, I ve had the smaller lighter HS 55s last 400 flights, but the control arms broke sometimes, in the early 2000s about a fifth of them had centering problems. Only experienced pilots should install servos smaller then HS 81s, nobody needs bigger. Standard size servos, often included with a radio, will not fit in an Easy Star. I ve used about a hundred HS 81s and have yet to have a problem with them. See below, I am no longer allowed to show others how to build, or fly, flying wings. Although there are a variety of final output gearing materials available, the basic plastic level works reliably in an Easy Star, you don t need metal gears. Better servos offer smother travel, more exact positioning etc, but that is not an advantage with the Easy Star. The servos installed in the prebuilt Easy Star, are, packaged under the Multiplex name, Hitek HS 81 servos. The electronic speed control for the motor also supplies the receiver in the airplane with all the required current, except if you use a high voltage battery. Any electronic speed control that you can buy shuts off the motor before there is too little power left for the remote control. Even when the motor controler cuts the motor off the air you have a long while left to land. 4

5 If you are going to use more then 10 Nickel Metal Hydride cells, or more then 3 Lipo cells, you either know what you are doing, or you are going to have to get a more expansive instructions. You really don t need more, I have built Easy Stars with up to 820 watts provided by 3 Lipo cells. That exceeded the upper limit. With one horse power at 38,000 RPM I was afraid of cutting my fingers off, the whole airplane shook long before getting going as fast as the motor could push it. And the noise... The Motor Beginnings: Updated for 2011 It used to be that we had two typed of motors, brushed and brushless. And, we had two types of batteries, Nickel based NiCad and NiMh plus Lithium types, mostly LiPo. Brushless motors are still included in some Multiplex kits, but they are being phased out, the performance of brushless motors so far exceeds brushed motors that nobody wants the old ones anymore. At a swap meet you can t give brushed motors or their controllers away. The batteries for flight are now all LiPo types, even though in the event of a crash the NiMh batteries held up better, LiPos won out. At a swap meet NiMh flight batteries are now worthless. If you are just starting out my recommendation for a flight power combination is to buy the combination Multiplex offers. That inrunner glues right in and provides at least hundreds of wonderful flights. Even after you crash an Easy Star enough times that purchase of a new airframe is a better option then repairing it again, the motor and controller usually can be reused. At the end of 2010 I went through my accumulation of flight stuff while building up another Mini Mag. Although it leaves out a whole lot of parameters, an estimate of how high an airplane climbs during a count of ten and then how long it takes to glide back down give a relative performance comparison. I didn t even try a Speed 400, long case Speed 400 or long case Speed 480. I did have a pair of ball bearing brushed cobalt magnet motors that are a big (30% relatively) improvement over long case Speed 4XX motors, and they were wound for voltages that a 2S LiPo would provide. Keep in mind that big is relative, the difference between batteries, almost trivial, can be more then the total difference between a ball bearing and plain brushed motors. With the Cobalt motor and modern 1800 mah 2S LiPo battery flights lasted about ten to twelve minutes in still air, almost all of it a full 13 amps. It would climb about 50 feet during a count to ten and took a count of ten to glide back down. Any wind over 5 miles an hour where it could not have been slope soared would have made the airplane near useless. If you are reading this for an introduction to flying, you aren t ready to surf an updraft, yet. When the 120 gram motor and prop were exchanged for an inexpensive 40 gram outrunner, with the same battery, the Mini Mag would climb about 230 feet at a count of ten and take about 45 seconds with a windmilling prop to glide back down, or about 55 seconds after fitting it with a folding prop and a speed controller including a brake that would stop it from continuing to free wheel turn with the amps off. With a better then cheap 80 gram inrunner on a 2S LiPo the climb improved to about 300 feet at a count of ten (at the same 20 amps), and the glide back down went to about 75 seconds. With the same 80 gram inrunner and a 3S Lipo (80 grams heavier then the 2S) the climb was so high I could no longer get a really accurate estimate, it looked like about 800 feet, and the glide back 5

6 down took over a count of 100. May I recommend not bothering with NiMh batteries and brushed motors! The section on brushed motors is included for reference only. Brushed Motors: This section is obsolete Included with the Easy Star kit is a well known small motor type Speed 400 in 6 Volt and either a white or black plastic propeller. The motor is intended for use in an airplane. Even if not visible from the outside, there are two little suppression condensers built in, they are essential. If you use direct current (brushed) motors only use those intended for use in an airplane, that therefore have the condensers. Both the Speed 4xx motors and their black or white propellers should be placed in retirement. For use in the Easy Star the propeller absolutely must turn clockwise as seen from behind, which with the previously supplied white Gunther proper meant removing it from the hub and reversing it. About 2008 the black Multiplex propellers became available. They were optimized for the 30 watts-out of a Speed 400, both the black and white propellers are now obsolete, nobody wants to fly with that low power anymore. The black propeller is optimized for 30 to 40 watts-out, although ideal for the Speed 400, it is not suitable for the much more powerful brushless combinations available today. For some reason pilots experienced with combustion machines were difficult to convince that in pusher configuration that the propeller must turn in the forwards direction. It s weird how they refuse to accept that. The direction which the propeller must turn is determined by the propeller, not by the power plant. Modern brushless electric motors may turn either way by just changing the order of the three wires connected to them. The fourth most common reason for it won t fly is that the propeller is installed backwards. The motor may be used with Nickel Metal Hydride (NiMh) batteries (Nickel Cadmium, otherwise known as Nicad are, because of the smaller capacity almost no longer available) which deliver an average of 1,2 Volt per individual cell. With six cells and therefore 7.2 Volts there is just barely enough to fly the airplane. If you bought the complete set from Multiplex up to about 2009, just such a battery was included. The goal of such a minimal motor output is that it is just possible for a beginner that is experienced with video games to teach himself (lady pilots, sadly, are very rare) how to fly with a minimum of financial outlay. Conditional however is that there is no wind at all and they are near sea level. I have observed it five cases, all of them were experienced RC model auto drivers. However, they were better off with help. Even if you are nearly broke I recommend not using the supplied 6 Volt Speed 400 motor in an Easy Star, get at least a long case Speed 400 or 480 instead. Nobody else wants them anymore and they are cheap to buy. More about that in the Examples section. But somehow that shinny new motor just demands from a lot of people that they use it anyway. An Easy Star will fly on a Speed 400 and 2S Lipo battery, but when you see how much better the modern stuff works remember that I tried to convince you to just set the Speed 400 off to one side... 6

7 The german language text originated in 2007 when NiMh batteries and brushed motors were still common. This is 2009, things have changed and we can skip most of that. Do yourself a favor and go straight to alternating current (brushless) motors and lithium Polymer batteries. Motors Continued, Brushless: We used to use direct current motors where the electricity was transmitted from the fixed case with it s magnets to the windings that were wound on the rotation output shaft through mechanical brushes. The motor took about a flight to wear in the brushes, delivered flat, to being round to match the armature and from then on started wearing out. Although the manufacturers play the numbers game by listing them as having an efficiency of as much as 75%, at the power levels required for flight they turned more then half of the power put into them into heat instead of turning the propeller. That s right, the actual efficiency was about 45% to 55%. The unrealistically high numbers also didn t take into account the increased friction from the propeller pulling on the output shaft. You could confirm that with your fingers, they got hot. Let s just forget about them from now on. Almost everybody now flying is using alternating current i.e brushless, motors which have no mechanical connections that transfer electricity to wear out. The position of the magnetic flux that pulls the output shaft around must be continuously varied as shaft turns, that varying location of the center of magnetism is now created by the motor speed control. How that lead is created, and how much lead to use is more complicated then can be explained here, and you don t need to really understand it yet anyway. Just remember that the better controls, which are more expensive, do a better job, and require some experience or help to get set right. For your first couple of controllers get a simple one such as the Multiplex ones, or my current favorite from Castle Creations. The internal description of what happens inside a motor is on a complexity of E equals MC squared, you can still get a Ph.D. investigating wound coil magnetic interactions. I want to fly, not do calculations. If you look at an electric motor under the hood of a car, or at a household fan, or almost any electric motor except in a radio controlled airplane, the magnets are fixed to the outside of the case and the wire windings are attached to the shaft that rotates. This works fine, except that the dynamics require higher rotations per minute (rpm) then the propellers our little airplanes require. It is possible to reverse the parts so that the outside turns and the wire windings stay put inside, this is called an outrunner motor. Accordingly, the traditional motor is now called an innrunner. Although currently about 85% of the market is for these high torque outrunner jewels, since for the Easy Star the outside of the motor is glued in place they are not a good choice for that airframe. Until we took up using electric motors to fly our little airplanes only a mechanical or electrical engineer needed to know anything about how to select an electric motor system. When we first started flying radio controlled airplanes with electric motors we mostly used stuff from the model auto set, and for a while we used their descriptions. That worked fine until we moved away from their sizes. That old discussions of the number of windings is not going to be applicable until after you have enough experience to need a more advanced guide then this one, we now use the engineering values. 7

8 Even a cheap brushless motor way outperforms a racing brushed motor. For a while brushless motor controllers were more expensive then brushed controllers, then they were about equal priced, now nobody flies with brushed motors so the comparison no longer matters. Along with it s physical size, the basic description of an electric motor s characteristics is it s kv coupled with how many watts it can accept as input. The kv stands for the number of times an unloaded motor will turn per applied volt in thousands of rotations per minute. There are a bunch of additional criteria, someday when you get to playing with the virtual dynamometers on the internet you ll see them, but this is the most basic numerical description to use for comparisons. The output of any motor is a result of it s own construction, the voltage applied to it and how the controler handles the lead, and the load i.e. the propeller at the actual flying speed. It s intricately interrelated, trial and error are how we determine what works although with computers to handle the basic investigation of what to use it goes a lot easier. When airborne recording became available we were surprised at how much less amperage we were actually using then presumed. With Lipo batteries you are going to be flying an Easy Star on either 2 or 3 cell batteries. For an Easy Star you need an inrunner in the diameter of 28 mm with a kv of between 2500 and 3500 weighing around 75 grams. That is the shortest size of a standard 28 mm inrunner motor. For a view into complexity a motor with the same kv that works fine in the 28 mm diameter 75 gram size is useless in the next size larger (either a larger diameter or longer length) in an Easy Star. You are restricted by the Easy Star airframe to a 6 inch maximum diameter propeller. An all encompassing explanation of selecting a motor would require an engineering type text book. An Easy Star is an defined airframe, so I can make seemingly definitive recommendations. Be aware though that although these are seemingly exact values, that nearly all of them vary more then most of you will ever understand. The kv of a motor varies, the lead from the controller, load (which varies with airframe speed) and rpm and so on and so forth. The pitch of the prop is not a constant hard number either. The battery voltage varies with it s charge. If you find yourself hopelessly confused, Multiplex offers well balanced propulsion systems for each of it s airplanes at a price that you cannot as economically collect together on your own. See above, the airplane is the least expensive part of the whole package, the propulsion system costs more then the airframe. Otherwise, try using what the other people you fly with are successfully using. Along the way it will start to make sense. Electric flight is vastly easier then fussing with the fuel burners, but you still need some personal ability to fiddle with things or some help. Most of us needed both. I cannot afford to be a member of any of the local flying clubs in Germany, but sometimes I just hang out there anyway. Model airplane clubs are nurds at critical mass, just about all of the men have a more continuous connection to having been boys then the average population. One nice day there was a teenager that wanted to learn to fly waiting for a club member to show him about it. But there I stood with an simple rear engine foam airplane, so, a club member was enlisted to use my airplane to teach him how to fly. Turn the transmitter on first, push in the wings, attach the battery and close the canopy. Climb out to about fifty yards and just go fly. That s all there is to it with a correctly tuned electric airplane. The time required to get in the air, less then one minute. When the battery ran out at twenty minutes it bounced off the ground on landing. We 8

9 just laughed, pushed the wings back in, checked for damage, swapped in a fully charged battery and went right back up. When the assigned trainer showed up it took an hour with a box of support equipment and fussing around to get a fuel burner into the air. The kid kept looking at me as if to ask is all this necessary. When it crashed, because the engine quit in the air, it cost a day and a half of repairs and a hundred Euros worth of parts. All that time spent breaking in the combustion engine was wasted! Many traditional model airplane enthusiasts reject foam airframes and despise the ease of electrics, a portion of them refuse to learn how they work. For them the satisfaction of flying an airplane they personally painstakingly glued together and shrunk the covering on, the smell of nitromethane, the constant fiddling with their unreliable reciprocating power plants and the scream of the combustion engine spraying castor oil all over everything are all inseparable parts of the experience to them. I m in it to fly, they can keep their fragile filthy noisy things. One day near Frankfurt am Main at a flying field that has everything from the oldest to the newest, a power pilot wasn t satisfied with the performance of his new electric powered airplane and decided to change to a larger prop. We all told him to measure the current draw, which he refused to do, the motor quickly burned up in the air. Another pilot whose 3 meter wingspan Euro 2000 model he nearly nailed (his day job is an airline copilot, you can almost see Germanys largest airport from the field) laid in to him that Lipos need to be at about the inner temperature of your body (90 degrees Fahrenheit/35 Centigrade) to work best, since he had launched with them at near freezing as they heated up the increasing current overwhelmed the motor. I then laid a model out where the components could easily be swapped out and proceeded with a watt meter to demonstrate to him the changes in current draw by changing propellers, batteries and motors. Half of the club came in to watch. At the end I deliberately over proped it to show him how the motor and controler heat up, when they have absorbed all the heat they can, they burn. Then I put a correct prop on and insisted he go fly my airplane. He got with it and learned how to use electrics. It s reminiscent of the discussions thirty five years ago when iron on shrink covering first became available about how real airplanes had to have silk and dope covering, traditions die hard. The Charger: this section was updated for 2011 By the time you read this Hitek may have changed the charger in the complete Ready to Fly set, if it s still for NiMh only you can still use it to charge the transmitter battery. LiPo batteries are much more sensitive then NiMh batteries were, but worth it for the flight pack and they are increasingly being used for everything. LiPos require a charger that can specifically charge them and a means of balancing the charge between the individual component cells. Get help with the selection. If you have no other guidance pick them from the Multiplex catalog, make sure you can balance the individual LiPo cells. That simple transformer based charger included with many starter all inclusive sets works fine for the equipment in the set. However, usually it has to be plugged into wall current, the rate of charge is matched to the battery that came with the set (so it either can t be used with smaller capacity batteries or takes a long time with larger ones) and it provides no information about the 9

10 battery and charge other then low (red light) or charged (green light). Sometimes simple is better, however the better chargers with a display provide a whole range of information about the condition of the batteries that you are going to need. Get a full range charger as soon as you can. When LiPos first came on the scene the manufacturers tried to adapt then existing charging equipment, which only sort of functioned. The issue was that while NiMh batteries in series (one right after the other) balanced themselves, LiPo batteries individual cells develop increasingly different voltages if charged as a single block. The voltage range of LiPos is critical, after enough charging cycles the differing voltages resulting from charging all of them in series produced not only a well below optimum charge, eventually one of the cells either under or over charged and chemically self destructed. For a while we just ignored the problem. Then there were various add on solutions, an effective and lowest cost one was the Astro Flight Blinkie balancer. The real solution was to equip each individual cell in a battery pack with it s own lead that was hooked into the electronics of the charger to level out the charge between the cells. Eventually all the chargers were fitted with balancers. The remaining problem being that the connectors are not yet standardized. If you are nearly broke and still want to fly, new or nearly new LiPo batteries can be used for a few flights without balancing. And, you could get by a little longer by have somebody with a balancer equipped charger balance yours once every five to ten flights or so. Some LiPo batteries do just fine for a good long while without a balancer, and some require it every charge. Not that any of us ever observed the supposedly memory effect in any of our flight or transmitter NiMh batteries (it did show up on cell phones, but not our airplanes), no LiPo battery has a memory of any kind. And while it took a few flights for NiMh batteries to break in, LiPo batteries require no break in of any kind, just go ahead and use them. New LiPo batteries are almost always shipped at half charge. Let me repeat that, there was NEVER any memory to NiMh batteries as used in an airplane, and LiPos require no break in at all. For a worthwhile deal on a charger check the web site of Neumotors out of San Diego California. The charger offered by the former F5B world champion is exactly what you need. The owner in his special deals section offers perfectly good, if slightly behind the times LiPos at a bargain price that are just right for any beginners airplane. Let the experienced pilots go for the high discharge rate and long life LiPos, for you as a beginner crashing sets the limit on the batteries life. I don t often recommend going cheap, but batteries is one place a beginner should. Even if you have to discard/replace some of the included components with the Multiplex Easy Star Package, it is still the most economical way to get started if you are starting with nothing. A goal of Hitek was to deliver a complete system for a minimal of cash, they hit it exactly right. It attracts beginners, who worry that their wife might discover the money that disappeared, and check it out, it flies. Never before was so much flight entertainment for so little outlay possible. 10

11 The market for chargers and batteries is constantly changing. Keep in mind that the charger makes every flight. Modern equipment is so much better then those from even a few years before that the purchase of a used charger more then two years old is not worthwhile. Do not let yourself be advised on equipment by model auto drivers, the requirements on their equipment are much different then ours. The second and third most common reason an electric airplane won t fly is trying to use used and new model auto parts. Although proficient with their own equipment for their purposes, power-plant wise the auto people are way behind the times, most of them still use heavy NiMh batteries and antique brushed motors! It has to do with that the minimum requirements for flight are much higher then for a car. The model auto drivers give full ampere only for a few seconds, we may use it for minutes at a time. Extra weight doesn t make much difference to a model auto, it s a big issue with flight. All model autos have a gear drive to match the motor to the load ect. Batteries: this section was updated for 2011 By the start of 2010 NiMh batteries to power the flight motor have all but disappeared from the scene. A few of us have NiMh flight packs laying around, they are still used to fly airplanes specifically configured for them, but as the NiMh motor batteries and the airplanes that fit them give out, we are not replacing them. For a very few of us we are powering the flight electronics separately from the motor controllers BEC, as a beginner you don t want that complexity. For now, most of the airborne equipment is still based on the voltages we used with Nickel chemistry i.e. 4.8 volts (4 NiMh cells was/is 98% of what is used and standard for almost all motor controllers Battery Eliminator Circuit i.e the on board power supply) or 6 volts (servos work a little better, but few people ever flew with five 1.2 volt NiMh cells), but, the manufacturers are converting everything, receiver, servos and transmitter included, over to directly use 2S LiPo voltage of about 7 volts. So, you probably still have NiMh batteries in your transmitter, and need to be able to charge them, but for the motivation of you airframe LiPo is currently the chemistry of choice. For now a majority of the transmitters in circulation still use NiMh batteries. Although a simple transformer type charger will function to charge the NiMh batteries in your transmitter, it s not all that effective in that it takes the day at home plugged into the wall, and the charge is not in conformance with the changing over use and temperature requirements of the batteries themselves. As soon as you can afford it get a cord that will connect the transmitters charging port to your charger. That five or ten bucks for the cable is worth it at the airfield and less then the cost of a single drive back to the house when the transmitter unexpectedly goes flat. I charge my 2200 mah AA size NiMh charger batteries at 1 amp. For now all available multi function chargers can still charge NiMh batteries. I have no idea how long the batteries in a transmitter should last, I am still using some 600 mah ones I bought back in 1997, after a couple of thousand flights they still power my almost as old Hitek AM 3 channel for about 3 hours just fine. The most common way to ruin a LiPo battery is by crashing the plane carrying it, the second most common is charging it wrong, the third is by attaching the connectors in a way that shorts 11

12 them out. That seemingly innocent spark blows a short in the battery that either ruins it right then and there, or, creates an internal short. An internally shorted LiPo battery that is not constantly recharged eventually runs itself down until the chemistry self destructs. The most common ways to create a battery short is using a side bit cutter to remove both leads of an existing connector (it simultaneously cuts through and shorts out the leads) and not first soldering one wire to the connector and insulating it BEFORE going on to the second. Those wires should be the same length and dangle into each other, that is why the manufacturers ship them with the ends covered. And every once in a while you are concentrating so hard on soldering, that you forget and reverse the polarity of leads. Connecting a motor controller with reversed polarity almost, but not quite, instantly destroy the motor controler. The electronics are ruined in a time on the order of 10 to the minus 12 seconds, which is about the time it takes light to travel across the room. By the time you see or smell the smoke it has already happened. Don t bother asking the manufacturer to repair it, buying a new one is cheaper. There is another common way to ruin a LiPo, by using it half charged on a motor controller that automatically senses if it is connected to NiMh or LiPo chemistry, or one that calculated the allowable voltage drop as a percentage of the initial voltage. There are two ways for the controler to recognize what kind of battery it is connected to; By sensing the voltage on connection (easy and therefore inexpensive to manufacturer), and by being set (programmed) forthe battery chemistry. Particularly in the case of 2S LiPos, that voltage is very close to NiMh and the controler may let the voltage fall to what is ok for NiMh, which ruins the chemistry of a LiPo, or, you connect a LiPo that is not completely charged and it lets the voltage drop to a preselected low, which is too low, and wrecks the LiPo. If at all possible always connect a LiPo fully charged. For a beginner without help the programming of which battery type is confusing, fortunately most controllers now on the market are pre-set for LiPo chemistry. If in doubt at the time of purchase get somebody who knows what they are doing to verify the settings. And do not fly with a half charged LiPo battery until you have enough experience to know when that is ok. Where this sneaks up on you is that the battery capacities now allow long flights, so you land and disconnect the battery half way through it s normal capacity. When you reconnect the LiPo the controler senses the new lower voltage of the partially discharged LiPo and sets the lower limit based on the now lower voltage, and it s too low. During the flight the power falls off and in getting back to the landing the battery is over discharged to self destruction. The capacity of a battery is... If you discharged a battery at a slow rate the amount it would provide into a load is about equal to the rating in mah. That mah stands for mili (one thousands) Amp hour. Accordingly a 2000 mah rated LiPo battery would supply 2 amps into a load for one hour. It s a quite a bit more complicated that that, don t worry about it for now. There are two types of C values for LiPos, the discharge rate and the charge rate. The origination of this type of rating was for how much current a LiPo battery can supply. If a 2000 mah battery is rated at 25C, that means it can sustain 50 amps for at least a little while. Sometimes they give dual discharge ratings such as 25/50. That means it can supply 100 amps 12

13 for 15 seconds and 50 amps for minutes. That higher value (and often the lower one too) is often overrated! And, recently as low internal resistance batteries suited for flight became more available, the charge rate is also given in C. For the 1C that we started with (and therefore didn t bother to specify) that meant a 2000 mah battery was to be recharged at a maximum of 2 amps. Recently 2, 3 and 5 C charging rate batteries have become available. In which case a 2C 2000 mah battery could be charged at 4 amps, 6 amps or 10 amps respectively. At 1C a 2000 mah battery takes a little over an hour to charge at 1C or 2 amps. The higher C ratings are great if you need them, but they cost more. Crashing sets the durability of batteries among beginners, when you chose your first LiPos, as a beginner the lower C ratings are just fine. Nowadays all but the cheapest of LiPo batteries lasts at least fifty flights, if you don t slam the airplane carrying it into something solid first. To review: If you have a 2000 mah LiPo Battery rated as 2C/25C it may be charged at 4 amps and deliver for fifteen seconds up to 50 amps. If in doubt, charge a little slower and watch those output peaks. In the competition to sell their product many of the lower cost products (which are preferable for you as a beginner) are overrated as to their discharge rates. If you use Multiplex airframes the most expensive single flight components as you stand there at the flying field are your batteries. When we started with LiPos they had discharge ratings in the 3C range. At 3C a 2000 mah LiPo could output 6 amps. In order to get enough discharge capacity we often had to run them together (parallel) and to get enough voltage we still have to add them (series). So a 2000 mah with the description of 2S2P stood for two 1000 mah LiPo cells in series and two LiPos cell pairs in parallel for a total of four individual battery cells composing the battery. Other then a very few competition machines (typically the $3000 F3A competition aerobatics fliers) nobody now needs to run the LiPo batteries in parallel to get the amperage capacity up, the xsxp has now been shortened to just xs. LiPo Batteries don t Last Forever By the very nature of their chemistry LiPo batteries lose a little capacity every year. If you leave them fully charged on the shelf, unused, they will lose about 5% capacity per year. If you nearly fully discharge them, and leave them on the shelf unused they lose about 4% per year. If they are half way between fully charged and fully discharged they lose the least capacity or about 3% per year. It would take controlled testing done on some rather expensive machinery to find the difference between 3% and 5% per year. Don t worry about it. For a while the magazines had feature articles about how to precisely run the batteries down. It might have to do with a practice the car people had of always running their NiCad batteries down in the thought that they developed a memory. We in airplanes used to laugh at them about it. As a beginner you need not care, other then to be careful what you pay for old stock and used batteries. In careful testing almost all new batteries have slightly less capacity then as labeled, the difference gets greater over time, and LiPos are still great, better then anything we ever dreamed of. 13

14 Easy Star Examples: The german text was not updated for The American text was brought into conformance with currently available materials for 2011 Costs are as of November 2009, all parts new in California including tax with me knowing where to get a best price while the walk in Hobby Shop stays in business. The most complicated part is the power set up, I can only provide likely examples. All setups include Hiteck HS-82 servo(s) (twenty dollars each if not bought as part of a new radio), a Hiteck 3 channel FM radio (pay the difference and swap the included two HS-55s for HS-81s when you buy the radio), (8) rechargeable NiMh AA size batteries plus a cable to connect the transmitter to the charger. Add $20 for the much better Spektrum Radio. The wings were fitted out with magnets to hold them together, all the connectors (Deans) were for use in an airplane and there was some selected reinforcement with fiberglass tape. A hundred and eight dollars gets you a first rate charger if you know where to get it, otherwise a hundred and thirty for a more average purchase, that is about the upper limit on what a beginner sport flier needs to spend on a battery charger. We bought new front line 2C/30C batteries that can charge in twenty minutes, older lower capacity ones can perform just fine even if they take longer to charge. We had a wattmeter to determine how the then unknown to us combinations worked. In other words complete modern equipment bought new and set up by somebody that knew what he was doing. I have seen airplanes fitted out with twelve dollar brushless motors, seventeen dollar controllers and five dollar servos fly fine, for a while. Those were internet prices and you have to be able to cope with things that don t always work, I have reservations about both the reliability and the durability of stuff that cheap. My one personal experience at the bottom end of the market was with a Euro 130 complete airplane system that was almost a copy of the Easy Star. The servos output shafts teeth wore off in two hours, the radio lasted fifty flights, the charger eighty, the motor speed control was electrically noisy and to save on costs they left out a couple of FETs so that it did not have the rated amperage on the sticker, the plane was a slug with a Speed 400 on 2S Lipos (but then, so is the Easy Star at 30 watts) and even after adding more power (the speed controler had to be replaced) it did not fly all that well. An Easy Star can easily handle much more weight, this one could not. It was made of good foam though and for the teenager I gave it to (after flight 93), Euro 5 replacement servos replaced speed controler and all, it was a big improvement over his all inclusive Euro 100 system. Part of the reason for buying such a cheap system was that it was complete to include a cable so the transmitter could be connected to a home computer for flying simulators. Since then the program FMS (which can be downloaded from the Internet for free) is currently available with a simple transmitter like controler for $28, any computer can run it. For a big jump up you can buy an amazingly good simulator including a controler that feels just like an inexpensive 4 channel transmitter for $53. A full range simulator costs $108, the really good ones cost $250, the computer requirements are proportional to the price. See the following warning about forgetting you have a family and a job.. Airplanes can be assembled from cheap parts and fly fine. There isn t much on the airframe itself to adjust the price. Almost nobody ever sells their Easy Star intact although if you find one of the other Multiplex airplanes for sale used they can be a good deal. Mini Mags and Easy Glider Electrics often outlast their first owners interest. If you 14

15 have to, an Easy Star is an ok place for cheap servos. It is impossible to advise you about every possible selection, therefore, here are some representative examples. If you have to keep it cheap: An Easy Star will fly on what was the stock setup of six NiMh flight batteries and a Speed 400. Many pilots have learned their stuff with them. But you are much more likely to crash with this, on the minimum lower limit thrust, then if you have more power. If we rate the crash frequency of an Easy Star with 100 watts-out as one, then trying to fly with the stock Speed 400 on 2S LiPo batteries means crashing about ten times as often. However, too much power can be a problem for beginners too, my usual personal 250 watts-out set up has a factor of three times as many crashes in the hands of raw beginners as the more aproiate 80 to 150 watts-out packages. Included with the Easy Star complete package setup was an 8 ampere motor speed controler that is maxed out with the 6 volt Speed 400 on 2S Lipos (or 6 cell NiMh batteries) and the 5 X 5 black plastic propeller. The Multiplex basic motor controllers have the advantage that they will automatically accept either Lipo or NiMh batteries with no need for settings by the user. With 2S Lipos or small 7 small cell NiMh the supplied Speed 400 motor is good for at least a hundred flights. Flights where you have to carefully balance on minimal thrust and only fly on days with almost no wind near sea level. A 6 Volt Speed 400 on full throttle with 3S Lipos will last up to one minute before burning up. Only a very few pilots with the required self control to never give full amps to a Speed 400 (or just for a few seconds, one limited his amperage with the computer in his transmitter) have been able to use the Speed 400 on 3S Lipos, but all of them already were experienced pilots already. I tried higher voltage Speed 400s, don t waste the effort. The 8 amp controller burns up first if you try 3S LiPos on the standard 6 Volt Speed 400. If you get the slightly more expensive 16 amp brushed motor controller you can run a more powerful brushed motor. Substitute a long case 6 Volt Speed 400 or 480 (better) for the with the kit supplied Speed 400. The motor is still limited to about ten amps for a 70 watts-in and 40 watts-out though. Or use (6) Sub C size batteries (the size cars use) in the capacity from 2500 mah to 4500 mah and a 6 X 4 APC prop. If you have to this also works with the black Multiplex propeller. Watch the motors output shaft diameter when selecting the propeller hub, it me be 2.3 mm or 3.0 mm or 3.2mm. This is heavier then other combinations, it will supply from (12) minutes on up of continuous motor run time for about fourty flights before the motor wears out. Because of the additional weight it has to fly and land a little faster, so there is more chance of damage on hitting something, the extra weight becomes a benefit in the form of easier control as the wind gets above eight miles an hour. At this weight you need to double the width of the rudder. Do not use this combination unless you already own a working brushed motor speed control (maybe available from a club member used at a nominal cost) and can get the motor for less then ten dollars as it is otherwise more cost effective when buying new stuff to go straight to brushless combinations. The easiest source of big NiMh batteries is a new car pack reconfigured to three above and three below. Just don t forget to replace that airplane killer Tamia connector 15

16 with something reliable, like those from Deans. NiMh batteries and the brushed motor both require a couple of runs to break in, let them run once on the bench. The set up is only cost effective if you can get the motor, controller and prop for not more then twenty dollars, the two battery(s) cost new about $25 each and you reconfiguring them yourself. In that case the savings works out to about eighty dollars, not including that the motor only lasts about as long as a beginner with his first airframe. This combination also works with 2S Lipos, many recent brushed motor controllers have the low voltage cut off required for Lipos, older ones don t. Where it really shines though is if you can shave another hundred bucks off by getting by with an older NiMh only charger, and maybe the batteries too, for nearly free. If that s what you can afford (that could be as little as $150- for a fitted out airframe not including radio and charger), it won t be as exhilarating or as durable as a brushless setup, but it s still fun. By 2010 even I quit building this combination. By then the improved costs and availability of LiPo batteries and brushless motors rendered this low performance combination pointless. If money is that tight try buying somebody s used setup and putting it into a new airframe or experiment with cheap Internet stuff. See below, I am a master scrounger, you are going to need some help if you buy used or cheap internet stuff. Still the best: Use a (28) mm outside diameter inrunner that weighs about (75) grams) with a kv of between 2500 and It should cost from $44- on up, $75- being a best price/performance choice (well matched combinations go to 84% estimated efficiency), the ultimate is a Neumotors 1105 (even on 2S they hit 90% efficiency and any two perform the same, not so for the cheap stuff, they can get up to 94% real demonstrable efficiency) for $120. You get what you pay for, the cheaper stuff is less effective and has problems, or soon develops them. That inexpensive motor has junk bearings, sloppy machining, soft materials that don t hold up, a percentage of them vibrate even when new, they have relatively poor efficiency (particularly at part amps, they are still a vast improvement over brushed motors), they may not be the specifications listed on the box so if you try to set it up without a way of determining how much power it is drawing everything burns up, ect. In an Easy Star the better motors are well justified as they often outlast the first two or three airframes. With the older high internal resistance Lipo Batteries a (25) amp controller worked with this combination on 3S Lipos, with modern batteries better use a (35) amp controller on 3S Lipos, the best current choice is the Castle Creations simple and inexpensive one. The lower kv works well with a 6 X 4 APC prop, the higher kv needs a 6 X 3 or 5.5 X 4.5 prop, which for reasons nobody understands are not currently available. This is about the only combination where 2S Lipos may be used for learning (or 8 cell AA NiMh batteries, or a seven cell car battery reconfigured to fit) followed by a switch to 3S Lipos for more then double the power. Usually substituting 2S Lipos for 3S Lipos without changing the prop just turns the airplane into a slug. It s an X squared thing. 2 squared is 4, 3 squared is 9. 9 is more then twice 4, and in reality going from 2 Lipo cells to 3 is even more power gain then that. 16

17 Not worth doing; Up to about 2010 I recommended not bothering to coax an innrunner into an Easy Star. To me, just because somebody else cobbled a motor mount in place didn t mean it s was worth doing. The 15 amp on 3S innrunner set up Multiplex offers for the Easy Star (or Mini Mag) is about ideal for a beginner. If you just have to use your outrunner set up try a Multiplex Easy Glider Electric or Mini Mag instead. Or trade what you have for what you need. But, outrunners are now 90% of what is available, and they now have pre-made plugs that allow the use of 40 to 50 gram outrunners that take up to 20 amps and it works out fine. If you have to use an outrunner combination in an Easy Star watch out that it moves the center of gravity rearwards and too many beginners don t know enough to add weight in the nose or use a heavier battery. But why not just do it right and put an inrunner in your Easy Star. A preferred learner combination: Towards the end of 2009 I built an Easy Star (I think it was the ninth) for a friend s ten year old son to learn to fly on. Although the combination was not as powerful as his father and I would have liked for ourselves, it was easily available, a little less expensive then full power and suited his son well. Despite the local dealers personal dislike of them, we used a Hitek (3) channel system with the throttle in back. I like these little Hiteck radios. Of I think fifteen that I have had, two transmitters failed early, the rest lasted a long time. Critical for this application, it fits in child size hands. We could set the motor for enough power for a slight climb and let the youngster concentrate on just the one stick. We selected decent rechargeable batteries for the transmitter (Sanyo Enelopes are the best), the cheap one time use batteries are a waste of money (unless you just have to get in the air now and that s all there is). Ask the dealer to help you getting a cable so you can charge the transmitter with the field battery charger. That plug into wall current transformer at home isn t much help at the flying field when the transmitter battery goes dead. The NiMh chemistry of the transmitters batteries requires a few tries to break in, the first charges go dead quickly. With modern 2000 mah Sanyo Enelopes at $2 each you have at least five hours of transmitter time. The Hitek FM receiver is fine as long as there aren t too many other FM transmitters going right next to you. Please try to remember the warning to NOT point the transmitters antenna at the airplane as if there were some kind of invisible line from it the airplane. If you get a FM one used and need an improvement, or just another receiver for another airplane, get the one from Berg by Castle Creations. For adult hands get a modern Giga Hertz frequency hopping system. The limited power of this setup was a benefit too, the sudden application of full throttle (250) watts output at the prop we originally planned for his father can unexpectedly shove the plane around and slam it into things. The motor, acquired used with almost no run time, was intended for use in a helicopter on three or four cell Lipos, it had a kv of On a 6 X 4 APC prop it drew fourteen amps on a 2S 2200 mah Lipo for an output of about eighty watts to the propeller. Commonly available inruners with kvs up to 3500 work fine on 2S Lipos. We had to add weight to the batteries to get it to balance. You might as well stick with an (17) amp controller 17

18 for this power set up as going to a 3S Lipo battery required a 5 X 3 propeller and was not really effective, the too fast speed of the propeller just went up in mostly noise. This motor was an odd one that has started showing up, an outrunner in a case. An inrunner is more efficient then an outrunner if they are turning at the same kv, provided it matches the propellers requirements, and weighs about ten percent less too. The rock over where the greater efficiency from an outrunner turning the propeller over slow verses running an inrunner at the lower end of their scale is, with the typical low cost 28 mm diameter setups on 2S and 3S Lipos, a kv of around With kvs under 2000 get an outrunner, above 2500 get an inrunner. If you find yourself flying next to me and wonder why my airplane performs so much better then yours, it s partly because I am the pilot, and because my airplane is using an inrunner. My Mini Mag is fitted with a 1700 kv 80 gram inrunner on 3S with an 7 X 4 folding prop. I can climb out of sight in a count of 25, it s all the little airplane can really use. As noted elsewhere, out of courtesy they call me a fool, instead of a smart... The above kvs only apply to the above size motors which are what usually fit in an Easy Star, Twin Star or Mini Mag and then only between 7 and 12 volts. Transmissions with modern brushless motors are not for beginners. So this one with a kv of 3200 was clearly in the wrong range from a technical sense. But, the slight extra weight and lower efficiency were less important then that I had it, since it was in a case we could glue it right in, even if it s wrong the market right now is convinced that outrunners are just the greatest, I scored it virtually new and cheap, the friend wanted something for his son... The friend, an excellent pilot with loads of flying wing experience, just could not be convinced that we had a learning airplane for his son that was not agile enough for him to land behind the shop where we often flew flying wings and routinely hit high voltage lines. Hitting the power lines started as just an accident, we used to make a sport of how many we could hit (the record is five out of six) and still continue the flight. At first look it s an unlikely place to fly, a steep rocky hill covered with brush and trees overlooking an industrial park, a fifty foot wide alley to land in and some really neat unpredictable winds around the buildings, but the new materials allow it. The AMA (The American Model Association, the source of insurance) doesn t. It s funny sometimes how such a simple toy can inspire so much excitement. And then there was the time a hyped up millionaire sports care owner who normally had full command of his surroundings, was dismayed, and ultimately calmed down, when he realized that his equally intelligent mechanic and engineer friend were going to go fly airplanes out back and he could come along and participate or not, we weren t going to work on restoring his old Ferrari just then. In a shop full of high dollar sports cars with a research MD in attendance we made the maiden flights. This combination isn t the most efficient or longest duration one, flights at continuous full amps last about fifteen minutes. He cracked the wing on the second landing by hitting a parked van, again. It was easily glued with CA back together, replacements wings are readily available for $25 and take only a minute with glue to assemble them, the dent in the wing didn t seem to make much difference. After that he used the plane as intended. That first hit would have destroyed any other material and were the motor in front, that too. There were no marks on the van to show the plane strikes. 18

19 His son thinks the plane is just great, the transmitter fits in his hands, it is fun to balance on gentle winds and thermals and it is easy to land. His father accepted that the times had moved on, I wasn t going to assemble the same old combination if the goal was for him to teach his son flying, at least not this time. The airplane soon had (70) flights with no additional repairs to it. With two of the modern fast charge Lipo batteries and the ability to charge from the car he can stay flying as long as he feels like it. His sons neck gets sore from flying it so much. We do however miss the flying wings though and in due time (when Multiplex makes the Xeno flying wing available in the USA) he will be buzzing around with them again. The new unused $220- Spektrum Ds6 radio (see above, you find yourself in a hobby store) will be used with other airplanes. His son caught on quickly and didn t need the capability to hook to another radio anyway. It s usually the older pilots that need the help of another pilot standing by with a second radio to override the beginners radio. And then there was the aging former F4-Phantom weapon s officer (he needed glasses and he refused to admit it) that just didn t like being on a harness with a nurd... In the end we had we gone straight to this set up the total net cost was, as of November 2009, about $470-. That was with everything bought new, but not including insurance. For that he has a hand built Easy Star (I do a better job of gluing them together then factory and didn t have to cut the Speed 400 motor out or run the third wire on the outside for the modern motor), a worthwhile charger with an integrated Lipo balancer, two 2C/35C 2S1P Lipos (2100 and 1800 mah) that can be recharged in twenty minutes, an 18 amp reliable speed controller, a quality brushless motor that won t wear out, and a 3 channel FM 72 MHz radio with rechargeable batteries and a charging cable. A set of replacement wings cost $25. A set of wings fitted with ailerons including extension cables, Y harness and an extended spar cost $100. It s worth it! You can t go bowling, or drink 40 ouncers at the beach for what this set up costs per hour of flight. We had a great time with flying wings, but these are the most satisfying just fly the thing planes ever made available. Getting the Servos to work: The holes in the control horns supplied with the Hiteck HS-81s do not match the wires used with the Easy Star perfectly. I chose nominal travel on the elevator with no slop by cutting down the round output horn. Because the servo/radio combination does not center the servo output at the neutral setting of the transmitters trim I set it forward (relative to the airplane) of center so that there is a little more up then down at the elevator with the trim set at neutral. For the rudder I wanted more travel, so I used the supplied X (cut the three extra arms off) and accepted some slop from the oversize hole. Beginners often forget to glue the servos in. Getting the perfect servo horns would have required another trip to the Hobby Store and most likely going through the boxes to find a more suitable servo that included an arm that could be re-drilled. Almost nobody notices the slight free play at the center of the ruder travel on an Easy Star anyway. Someday when you go to higher performance airplanes getting things slop free will be very important, but not with the airplanes described here. If you buy the complete setup from Multiplex the servo arms match the control wires. 19

20 I ruined a $25- servo in a foam motor sail plane (where it could not afterwards be accessed) by using to much CA glue. No liquid went in to the servo, but the fumes condensed in the gears. I now use Goop glue for all servos. Run the servos on the bench a few times and make sure you center them correctly before gluing them in. You get one easy try to assemble a foam airplane. Break in of Lipo batteries and Brushless Motors: Contrary to anything else you may have heard, LiPo batteries require no break in of any kind. As the owner of Thunder XXX put it I got so tired of telling that to people who didn t want to believe it, that I finally told them to go gentle the first few flights. The same almost applies to modern brushless motors, they have no break in requirements, but if it makes you feel better run a battery load through at low amps first. What does happen is that the skirts to keep dirt out of the bearings and the lubricant in wear. Racing bearings don t have much free play in the bearings, others do. Cheap motors have cheap bearings, that quickly wear out. Motor controller capacity: There are so many variables in the component parts that you really need to have access to a means of measuring how many amps a set up uses. The highest demand on the regulator is when the load is too high at part throttle. Creeping up on a combination by starting low just burns out that regulator if it s has too small a capacity. I use an older 40/55 amp speed control that was made before Lipos and their different from NiMh batteries low voltage cut off to run in new combinations, I paid $12 used for it. A usable watt meter costs $65-, if you continue with this hobby it will be in continuous use. Measuring the current and voltage is required every time ANYTHING, prop (even a different brand with the same marked diameter and pitch), lower internal resistance batteries, a different motor ect. is changed. It can also identify a servo drawing continuous power because it is either hanging up or defective. For those of you starting out, get help at either the flying field, or at the Hobby Shop. You are going to get help aren t you? We found out the hard way with brushed motors that it was cheaper to get an oversize controller then to splatter the whole airplane from using one that we thought was big enough. As the motors wore in and out together with variable battery performance the limits of the controllers were unknowingly exceeded. With the modern brushless controllers that no longer appears to be the case. Get it set up right and it will fly until something, like the bearings in a cheap motor wear out, or you change to lower internal resistance (i.e. higher C rated) batteries, changes. But, they now give the capacity of the on the motor controller power supply (BEC battery eliminator circuit) in amps. An Easy Star can fly fine with a 1 amp BEC, 2 amps is better. Beginners tend to want to fly with things bent and binding, that drives up the loads on the servos and BEC. Somehow 6 X 5 and 6 X 6 propellers don t work in an Easy Star, just too much mismatch between propeller and airframe speeds. 20