Newbies!!
Everybody at some stage has been a beginner. Even me!!( I still am ) So nothing wrong with it. Starting an hobby like heli models is a very sophisticated way to burn serious amounts of money. But many hobbies are like this. Think about women! That's an expensive hobby. Some start from airplanes, some others, like me, from scratch. Starting from airplanes can be good in the sense that you will have a feeling for the sticks that I didn't have when I started the thing. Anyway, after you make up your mind about helis, what you need is basically a heli model, the engine, a radio set, 5 servos, a gyroscope, and some bit and pieces like battery chargers, starters, fuel can etc etc. So let's proceed with order.
There are many models on the market nowadays, and none of them can be defined a bad one. All them are quite flyable, reliable and cheap. Usually beginners start with a 30 size. Well, what is a 30 size? Helimodels are divided in several categories. Usually the size is the type of engine that would fit in the airframe. So we have 30 size, which accomodate engines from 28 to 36, 45 size, with engines aroun 45-50, 60 size, with engine between 60 and 70. The number indicates the displacement of the engine in cubic inches. A 36 is an engine with a displacement of 0.36 cu.inch., as to say 5.5 cc. Then there are gassers, which are mainly modified 60 size with a 23 cc petrol engine, and giant scale. So as a starting machine the best choice would be a popular and reliable 30 size. Bigger machines are more stable and maybe easier to fly, but they are more expensive to buy and run, and a crash usually is a lot more expensive. Yes, you will crash sometime. Big helis are also more frightening and so the shaking knees factor will probably affect your learning curve. Very popular 30 size are the Hirobo Shuttle, the Kyosho Concept 30 or Nexus 30. They are very reliable and quite common. A very important factor choosing a model is how popular is the model in your area. This can be found out asking at the model shop or in the club. You will need a lot of advice so better going for models which are well known. Will be also easier to get spares and second hand parts. A second hand model can also be a good choice. My Shuttle for example is a second hand one, it's very easy to find second hand machines with little or no flight time. Yes, flying heli models ain't easy, so lots of folks give up and sell the chopper for pennies. Plastic 30 sizes are not affected by crashes if properly fixed, and last long, so they can be bought without big concern. Make sure you get the model with manual and accessories like starter shaft. If you buy a used model, a good thing is to disassemble it completely and reassemble it. In this way you will check all the parts and you will have a better knowledge of the machine, that is important. Some models are available ARTF, that means almost ready to fly. Same advice.
There are many makes of engines for helimodels. The best-seller is the OS I believe. It has a very good reputation around the world, it's decently powerful and very good looking. Super Tigre are very good and almost undestructible. Good italian stuff! But I have some buddies who have cheap engines like the SC, and they run flawlessly. I have a Thunder Tiger in my bird and it works fine. Never had a quit and I'm still running the original plug with at least 40 hours now. So I'd say that any engine would do fine, just look after it, set the carburation properly, check the main bearing every now and then, don't overheat it and it will run forever.
A computer radio is mandatory for choppers. No point using an analog set. An heli requires at least 5 channels, but you could need another one for the gyro. So a 6 channel set is the starting point. A good radio set with a user friendly interface would make things a lot easier setting up the machine. An itermediate range radio set like a JR3810 or a Futaba FF8 has enough features to satisfy your needs for years. There is a discussion going on about the PCM vs. PPM. The PPM, aka FM, is a cheaper choice than the PCM, but the PCM gives you the higher resolution and higher reliability of a digital transmission. With the PPM an interference will drive your model nuts. An interference with a PCM link will be simply ignored by the receiver, or will trigger the fail safe. The fail safe is a feature of the PCM system. When the receiver receives an interference or the link is broken, it can be programmed so the servos will keep the last position ot will go to a preprogrammed position. Very useful. A PPM receiver would just start moving servos randomly. Personally I prefer the PCM. Is more expensive but I'm not going to send my expensive toys airborne with a PPM link. I never had any problem whatsoever with the PCM rig, I had some minor problems with PPM. I already have BIG problems to keep it up (the heli), don't need any more trouble with interference or something. Computer sets also allow you to have more models with the same transmitter or different setups for the same model.
An heli model usually requires a minimum of 5 servos. Throttle, aileron, elevator, rudder, collective pitch. Good ballraced servos are a better choice, because vibrations (heli usually vibrate) eat up the bushings, and after a while the servos get sloppy. For a 30 size standard ballraced servos like the Futaba 3001, the JR517 or the Hitec 525 are ok. For 60 size stronger servos are required. Sometime it's a better choice a fast servo for the rudder.
Gyro.
The first time I heard about gyros on helimodels i thought: what the hell is the gyro? I mean, I know what a gyro is, but what's the story about it? You sure noticed that helis usually have a small propeller in the tail, called tail rotor or anti-torque rotor. The fact is that the main rotor, when driven by the engine, generates a torque that tends to spin the chopper in the opposite direction of the mainrotor rotation. So the tail rotor couteract this tendency. In a model, small changes in power induced by the controls or by carburation changes or who knows what, generates torque variations. This means that the tail will be constantly wagging. Very nasty! You might see your chopper facing you in a split second, and usually that means a broken chopper, if you can't hover nose-in. So here comes useful this device. The gyro is basically a device that, by means of a mechanical gyroscope or electronic solid state technology, senses the changes in heading and damps them. Is not a compass, but a yaw damper. Once set up properly, it will keep the tail reasonably steady. The last gyro generation has, with the aid of microprocessors and sophisticated software, heading hold capabilities. This means that the gyro will keep the heading no matter what. Very nice, but also very tricky. You can get caught in very unusual attitudes. During a turn in forward flight the heli will go from forward flight to sideways flight and then tail-first flight, because the gyro will keep the heading and the tail won't follow. Mechanical gyros are progressivly disappearing from the market, because piezo units are getting cheaper. Piezo also have less power consuption, and can keep crashes better. Usually in a bad crash a mechanical gyro won't survive. I will definitely recommend a piezo gyro. Possibly a dual rate. You will need an extra channel on the radio for this. An heading-hold unit will be a big help for a beginner, because the tail will stay steady. One thing less to worry about. But they are a bit more expensive. Well, if you can afford it, go for it.
You will need some accessories to run the business of flying heli models. Some of this items are mandatory, some other are a plus. First you will need a box where to put all the accessories. There is a large range of choice. Then a fuel cal. Yes, you will need to carry some fuel with you, and while you can use any bottle or container, a can with a pump will be very handy, and they cost few $. A hand pump will do fine, there are also electric pump or you can pick one from a scrapyard. Some cars have a small electric pump for the windshield wash and it can be easily adapted. They work with 12V. Then you will need a rig to power the glow plug. Model engines usually have a small glow plug that needs to be warmed up electrically. There are many systems. Personally I use the 12V from a gel battery with a car bulb between the battery and the clip. It works fine, is reliable, cheap, and when the bulb is lit also the glow plug is. Once the engine is started the heat from the combustion will keep the glow plug lit. Some models have a pull start, same as your chainsaw. But they are progressivly disappearing. The latest models have a hexagonal starter shaft, like a long allen key, or a cone starter. This involves the use of an electric starter. They are units that can be purchased at the local model shop. Also a reversable drill can use. I used a drill for a year and it worked fine. I just fitted the hex starter shaft in the drill. Piece of cake. Another item you will need is a battery charger. Models have a battery aboard and the transmitter also has a battery. They need to be charged. If they are not, a slight loss of control can occur!! So don't save on the battery charger. Use a drill, bring the fuel in a Coke can, lit the glowplug with a match but buy a good charger. Batteries will last long and the charge will be good, and in the long run you will save money. Maybe a lot of it, if you can avoid a crash caused by a flat battery. I've been lucky, I incurred in a flat receiver battery twice, but both times I've been able to land the model in time. So no messin around with the charger. DON'T use those cheap-o charger you usually get with the radio gear. They are not reliable and there is no way to check if the battery is really charged or not. And they ruin batteries. Get also a pitch gauge. It measures the pitch if the main rotor blades. You will need it for all your heli modeler career.
An item you will definitely need as a newbie is a training undercarriage. Is a rig that gives the model more stability on the ground. While learning you will be hopping around and a wide undercarriage will avoid contact of the rotor with the ground. There are some carriages available, but you can build your own. Buy some plastic conduit for electric ducts. Cut two piexes of 120-130 cm. each. Bend upwards the extremities at 20 cm. from the end warming up the plastic with a hairdrier. Join the two pieces with a X joint and fit it to the model with zip strips and tape. It works just fine, it's light and cheap.
I will outline very briefly how to set up the heli. This can vary from model to model. Anyway you are supposed to hover the heli with the stick in the mid position. So get the gauge, fit it to one blade and check the pitch with the stick in the bottom position. It should be between -2 and 0 degrees. As a beginner 0 degrees will be OK. Then check at mid-stick. It should be around 5-6 degrees. Stick at the top position should give a pitch of 9-10 degrees. You will learn with the experience how to do it. You should find this outlined in the model's manual. You can have also a look at the Shuttle manual in my homepage. The process is about the same for all helis. The power will go from 0% at the bottom, 40-50% at mid-stick and 100% at full stick. Check the aileron and elevator movement of the swash plate in all collective stick position. If you have a good gyro you can leave the programming of the revo mix on 0% or disable it. I know I will be flamed for saying this. But after working my butt to the bones to find a perfect revo mixing in my models, I found out that disabling it completely doesn't change the behaviour of the model at all!! So don't worry about it. Check the swash plate. It should be flat in the center stick position for aileron and elevator. Once started the engine the tickover has to be set up so with the throttle trim in mid position the engine is revved up enough to stay running, but without engaging the clutch. The engine should quit bringing the throttle trim to zero. If it doesn't, how do you thing you will shut the engine off???
Ok, you got the heli, radio, starter and a decent set up. Get a large parking lot, fit the training carriage, start tne engine and go! bringing slowly up the throttle stick, the heli should start getting light on the skids and lift off at about half stick travel. Try to trim the control, rudder, aileron, elevator, so the heli will lift off flat without going in any direction except up. This is no absolute because wind or a starting position not flat will induce some translation. But try to do it. Then start hopping around. You can practice it in a small area, but a large one will help you because you won't need to stop the rotor and put the model in place again every 3 minutes. In a large parking you will just skid and hop around. Slowly the time you will be able to keep it up will increase until you will realize you can hover as long as you want and without moving from the spot. This may take some time. But that is what you need. Burn fuel, don't be eager, the learning curve is quite flat with helis, don't expect to be able to hover consistently the first weekend. Is not advisable to go and fly for hours. Burns 2 or three tanks of fuel but take a break between them. Expecially at the beginning you will find yourself tired and stressed, so take your time. Personally took me about three months to learn how to hoved decently, but I was on my own. No lessons, no simulator, no advice. After you can hover consistently you can take the training gear off. Then you will have to learn again. Without the gear the heli behaves a bit different but it will seems to you VERY different. Don't worry. Again check the Shuttle manual because there are a lot of good suggestions and advice I won't write here. While learning get used to check the fuel, the battery, the heli. Make up your own checklist for pre-flight, starting, post-flight. Check the screws, expecially in new birds. You will find that some of them will get loose. Tight them and use thread lock. Helis vibrate a lot and vibration make funny things. If you can't unscrew a nut just put it on the model and it will get loose within seconds. If you have the chance and can afford it, take lessons. 20 minutes of lesson is worth 200 of training. The teacher will give you also loads of advice. I give you three advices. Burn fuel, burn fuel, burn fuel. I used to keep the model in the trunk of the car. Whenever I had half an hour I found a place and practiced hovering.
Yes you will crash. Is not nice and it hurts your pride and your wallet. Two crashes a year are ok. Well, no crash is better, but no crash is impossible. You have to dare sometimes. But don't push the envelope. If you crash more that twice a year you are either bloody unlucky or you are pushing too hard. Slow it down. Crashing usually affects your confidence. Try to understand why you crashed. A servo failure? It may be bad luck or a crappy servo. Run out of fuel? He he! Flat battery? Aaarrgghh. Get a battery checker and a good charger. Charge the batteries. Change the batteries. Running out of fuel is a shame, but seldom dangerous. Usually helis or any flying devices joins soon the terrain when the engine quits. A flat battery means an out of control flying lawn-mower. Very dangerous. Lost control? It happens. Practice more. Consider that if you stay out of the business for 6 months will take a little while to get your skills back 100%. Keep a crash kit. Usually in a crash the same items gets damaged. Blades, tail boom, main shaft, feathering spindle, flybar. After a crash you will be able to fix the machine and fly again soon. Interferences? Uuuuhhhmmmm. Very old excuse! I've very seldom seen a modern model shot down by an interference. I've seen many planes hitting the deck in a flat spin and the pilot screaming "Interference!!!". Bullshit, it was a flat spin! Once I've seen a large model, a Cranfield, 50cc engine, joining the terrain at the third flight and the owner crying and blaming interferences. As it turned up later, it was a desctructive flutter in the elevator. Poor costruction, that was all.
Make up your check lists. Expecially pre-start check-list. I suggest you one.
Visual check of all linkages, belts, nuts, bolts, canopy.
Refuel the heli and check free filter and fuel line, check pressurization line.
Turn on receiver and check the battery
Turn on transmitter and check battery, trims, hold switch, idle-up switch
Check all the controls, throttle, collective, elevator, aileron, rudder moving at full excursion the sticks, checking the controls move in the right direction (is the model memory the right one?)
Set the throttle switch to half and set the throttle stick to idle.
Double check batteries, model selected in the radio, trims, switches and throttle stick.
Connect the glow plug power. Happened to me twice that the engine would start just connecting the glow plug. Weird isn't it? Big troubles if the receiver is off.
Hold firmly the blade grips and start the engine. Grabbing the blade grips is very important because if for any reason you start the engine at full throttle ( and sooner or later you will!) you will be able to shut id down without any damage. If you need to kill the engine quick just close the exhaust with a finger before it gets too hot. Don't try to close the fuel!!
Wait few seconds, rev a little the engine, disconnect the glow plug and put the heli in place. Good flight!!
What that does mean? When you are learning you have an envelope around you. Learning you enlarge this envelope pushing. So you will fly higher and farer and faster. But if you push too hard the envelope breaks. Crash!!
Helis are dangerous toys. They can be flown in very little areas like your back garden or a park. But be careful. A mechanical failure or a loss of control can always happen. Stay away from electricity lines. Flying choppers do draw a crowd, and dogs will try to eat the rotor, and children will walk towards the bird and you will see them when they are very close, because you will be hypnotized by the model. Somebody walking close to the model can distract you and you might lose control and crash. Once a dog attacked my heli. I was at my first hovering without training gear and I had an hard time trying to keep it high enough and then landing with bad shakes. Don't forget a mechanical failure can always occur. So don't hover the heli too close expecially at the beginning. Keep people away, I know is nice having some audience, but once I crashed because some people was there so I did another round and run out of fuel in a 90% bank turn. Very dodgy auto and boom!! You will probably fly in some club. In that case check the frequency of the other guys flying, but I'm almost sure they will do it for you!!
I almost forgot the most important thing, the Murphy's law. Murphy was an aeronautical engineer who enunced this law: If something can go wrong, it will. This is the No.1 law in designing and building flying devices and complex machines. Few years ago a brand new liner, I believe was a 757, had a fire in an engine. The pilot shut off the engine. The good one. The aiplane went down and the pilot managed to land on an highway. The lights which indicated fire in the engines were inverted. Murphy's law. So check very well everything, from batteries to screws. A failure sooner or later will occur. Better later.
In most countries you must have an insurance to fly models. Get an insurance anyway because the amount of damage a model can make is relevant. Few years ago a chap died in an helimodel accident in Italy. The man crossed the runway and a 60 size in a fast flyby hit him. I used to go to this club in Italy. There were few guys flying pulso jet models. The pulsojet engine was used on the notorius V1 flying bombs during WWII. They are indeed flying bombs. The engine is very simple, is fed with gasoline and one litre of fuel lasts 5 minutes. The most used model is called Saggitario and it carries a litre of gas. The tank is just in front of the engine, which gets red hot in flight. When the model crashes a fire always occur. Once, in a very windy and hot day I've seen a Saggitario crashing due to the loss of a wing (wings are made out of polystirene and gas eats polystirene!!). A bush fire front of over 2 miles resulted. Another time I've seen a guy flying the pulsojet directly in a electric transformation house. It took fire and the whole area went on a black-out. Did I tell you that modelers are indeed the worst nutters in the world?
A simulator is a definite help for learning. I recommend it. It's worth the money spent and will save you loads of dosh. One crash avoided and the simulator is for free. You need a PC though. Most simulators can be used with your tranny through the training cord. The most used and probably the best simulator is the CSM. It is not the best for the graphics, but it is very realistic and fiddling with parameters you can make it work exactly like your model. Very useful in bad weather or at night. Or waiting for parts to fix your chopper crashed last week.
This page has been visited
times.