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Setting up an RC Helicopter

Setting Up a Helicopter

Raptor 30 HeliFirst thing after you bring your newly purchased Helicopter home, regardless whether it’s new or second hand, is to check that the helicopter is properly set up. Even an experienced helicopter pilot will not be able to fly an improperly set up helicopter. He might not crash it if he is lucky, but he will definitely have a hell of a time trying to fly it right.
A properly set up helicopter will fly the way you want it to. You will not have to fight the controls just to get the helicopter to a position you want it at. Flying improperly set up helicopters is both a risk to yourself and others so please make sure you do it correctly.
The things that are most important to look out for are as follows.
Make sure all parts are secure – You wouldn’t want a screw to work loose during flight. A helicopter needs all its parts to be working in harmony for a successful flight. Any parts which work loose during flight will most definitely be the end of your helicopter. If you’re lucky it will meet terra firma. If you’re not, it will meet someone before crashing. So make sure all parts are secured and put on some lock-tite (threadlock) for all metal to metal screws. Do not put threadlock on metal screws that will contact plastic.
Make sure your blades are properly balanced – There are many things to balance for a helicopter. Firstly are the main blades, you have to make sure that the rotor blades are properly balanced laterally and horizontally. This will ensure that no vibrations creep in when your rotor spins. When you are done with your main blades, make sure your tail blades are balanced the same way. As soon as you see any vibrations on your helicopter, land it and make sure you fix the problem. Vibrations are the source of many mechanical failures. Parts will work loose during flight and wear and tear will be exaggerated. A well balanced vibration free helicopter is a pleasure to fly and it will appear to run smoothly at all times.
Make sure your Helicopter is properly balanced – Do not fly with a nose or tail heavy helicopter. Apart from loosing unnecessary power in maintaining proper balance during flight, you will once again increase unnecessary wear and tear on the swash plate. To balance a helicopter, make sure the helicopter balances at the main rotor shaft. Pick up the helicopter by the rotor head and make sure the helicopter and tail boom is parallel to a horizontal reference. Once that is achieved, your helicopter is properly balanced. In achieving perfect balance, try not to add any unnecessary weight to the helicopter if possible. A heavier craft although more stable will use up unnecessary power. Try to balance the helicopter by re-arranging the positions of your onboard equipment, which may be the servos, battery packs or even gyro.
Make sure no bindings occur – Very important in the functioning of the helicopter is to ensure that no moving parts bind. Make sure the gears are not meshing too tightly since they draw power and increase wear and tear. Other areas of binding might occur on your swash plates. If the swash plates seem to be binding, just reduce the throw of the servos enough to a point where full stick movement will not cause the cyclic swash plate movements to bind.
Ensure servos and equipment are properly installed – When installing servos, make sure that they are properly secured to the craft with no free play or movement. Also make sure that the servo travel direction is properly corresponding to your intended stick movement. If they are not, reverse the servo direction either mechanically if possible or though the controller. As a general rule, ensure linkages from the servo horns are at 90 degrees position at center stick. This ensures linear movement on both sides of travel.
Make sure your Pitch Settings are correct – There are many ways to set up your pitch for your collective pitch helicopter rotors. All of it is based on personal preferences and flying style. However a general guideline would be to ensure that your pitch throws do not exceed the maximum recommended pitch for the helicopter in both positive and negative pitch positions. Make sure that the negative pitch does not exceed maximum when the throttle stick is moved all the way to the bottom and likewise ensure that the positive pitch does not exceed its maximum when you move the stick all the way to the top. For beginners, you might want to set 1 or 2 degrees positive pitch for bottom stick position until you are more used to flying a helicopter with negative pitch or you might get a nasty surprise of “helicopter meets ground REAL FAST” when you redude throttle. Apart from getting the pitch correct for the main blades, ensure that the rotor head paddles are in line with each other with 0 degrees pitch when the swash plate is level. Having positive or negative pitch will only create unnecessary drag and loss of power.
 

ADVISE TO BEGINNERS: If possible, always get an experienced pilot to help you with your first setup and flight. Even after a helicopter has been properly set up, you will still need to fine tune the trim on the helicopter to make sure everything is perfect. This is where most beginners, especially those who don’t know how to hover yet (even on a properly set up machine) might crash and get disheartened

Choosing a RC Helicopter

Choosing a Helicopter      
THE BUDGET
For beginners into this hobby, the first question that comes into mind is which helicopter to buy. This is very often associated strongly with the budget available. A word of warning is that this hobby is not cheap by any means. Even if you find purchasing your first helicopter affordable and cheap, you will soon find that repair and maintenance costs will amount to quite a bit. Of course you will also soon learn that the “itch factor” will kick in and you will find yourself spending money on parts, upgrades or even new helicopters just because this hobby is so darn addictive. Anyway you have been warned. Now is the time to read on and enjoy!
Also please keep in mind that even the most experienced pilots will have a crash or two now and then. This could be due to sheer cockiness or lack of concentration or even mechanical failure when flying a helicopter. Replacing parts on a precision machine could really run up your budget. If you are cost conscious then a good place to start would be a .30 size engine helicopter with collective pitch and good availability of parts.
    

CHOOSING THE RIGHT HELICOPTER
 Raptor 30Deciding on your first helicopter can give you a migraine. You can basically choose from two types of helicopters; a collective pitch or a non-collective pitch machine.
A collective pitch machine basically means that the pitch of the rotor blades changes according to your throttle/pitch stick position. A non-collective pitch machine means that the blades are of fixed pitch and the lift of a helicopter is basically controlled by increasing or decreasing the speed at which the rotor turns.
To the beginner, a collective pitch machine is harder to set up but is easier to fly because it can maintain constant head speed all the time which means control is always there regardless whether you are ascending or descending. The collective pitch machine is also more expensive due to more moving parts and the requirement to have an added servo for pitch control. A collective pitch machine is always recommended for beginners but if budget is a limitation factor, you can always learn to fly on a fixed pitch machine like I did on a “Mini Dragonfly”. Additionally the collective pitch machine will allow you to develop your flying skills without having to upgrade from a fixed pitch machine later on.
 

    Quick Lesson on Head Speed & Control: The faster a set of rotor blades spin, the better response you will have from the cyclic controls. For a collective pitch machine, you can set the rotor to spin at a certain fixed rate e.g. 100% throttle and yet have the helicopter remain on the ground by having 0 degrees of pitch on the blades. Normally this does not happen but it just basically illustrates how a collective pitch machine is different from a fixed pitch machine which will take off even before you hit the 100% throttle position. You can never change the throttle & pitch combination. To descend on a Fixed Pitch helicopter, you will have to reduce throttle to reduce the rotor head speed which is equivalent to lift. This in-turn will effectively reduce the amount of cyclic control on the helicopter thus making it more sluggish. This is the main reason why it is easier for the beginner to learn to fly on a Collective Pitch Machine.

In addition to the helicopter type (Collective & Fixed Pitch), the size of a helicopter will dictate the stability and reaction time for each model. Generally the bigger the helicopter, the more “stable” the craft, especially in stronger winds. Small micro / mini electric helicopters will definitely be more twitchy as compared to the larger gas powered ones. The sheer weight of larger machines normally weighs down the machine making it more sluggish and allowing beginners to have more reaction time. However larger machines are by no means sluggish as the power plant is normally more than enough to make them perform the wildest acrobatic maneuvers. The ability of each helicopter to perform stunts depends on the design of the craft in addition to the power plant it has.
 

THE POWER PLANT (ENGINE / MOTOR)
OS .91 Heli Engine An engine for a helicopter is similar to that of a model aircraft engine. The only difference is the larger heat sink on top of the engine for better cooling. Model Engines normally will require model fuel and a host of other accessories to start, run and maintain the engines (e.g. electric starters & etc)
Motors that comes with electric model helicopters are normally “Brushed” Motors. These tend to wear out relatively quickly and you will find that you will need to upgrade to “Brushless” motors (along with brushless speed controllers) if you’re really serious about flying and wish to put the helicopter through its many hours of flight. For better long lasting flights, people normally use lipo (lithium polymer) batteries as opposed to Nicad / Ni-MH batteries. Other accessories like a special lipo battery charger will be required plus the batteries can be just as costly as model fuel since they tend to damage easily under excessive current load or drainage.
 

THE RADIO & RECEIVER
JR Propo PCM 9XII Controller Helicopter Radios are different from Aircraft radios in many ways. The most obvious is the capability of Helicopter Radios to electronically mix certain functions like pitch and throttle (via curves or points), tail rotor and throttle via Revo Mixing. Most radio these days have different modes that allow a modeler to switch between Airplane, Helicopter and Glider Modes like the JR 9XII Radio that I have. Most radios also hold quite a number of model memories which means you can use the same controller with different models that you own. All you would need are extra sets of receivers and servos.
Different radios come with different servos & receivers. Some even come with nicad battery packs while others don’t. It is important that for helicopter radios to have servos with output shafts that are ball-bearing driven to reduce friction under heavy constant usage & vibrations from a helicopter. Speedy servos are also important for increased response times especially for the tail rotor control which is normally connected through gyros. Many helicopter radios come packaged with five ball bearing-ed servos and a large batter packs to handle the extra load and movements on servos.
Futaba S 9252 Hi-Torque Ball Bearing Servo The things to look out for and to have in a helicopter radio would be:

  • Ball-Bearing Servos (5 Servos are needed: Throttle, Collective Pitch, Tail Rotor, Cyclic Left/Right, Cyclic Forward/Backward)
  • Large capacity receiver/servo battery packs 1200mah or more
  • Minimum 5 points Throttle & Pitch Curve settings
  • Throttle Hold Capability
  • 3 Flight Modes (Normal, Idle Up 1 & Idle Up 2)
  • Revo Mixing
  • PCM / PPM Receiver

 

GYROS
 Just like other equipment on board a helicopter, the gyro is perhaps the most important aid equipment that will help a modeler pilot his helicopter. A gyro is basically an electro-mechanical device used in a helicopter to help stabilize the tail of a helicopter during flight. As with all gyroscopes, it aids by detecting unwanted movements around the yawing axis. An unwanted right handed swing of the chopper will be countered by a left input of the tail by the gyro to maintain heading of the chopper & vice-versa for a left handed swing. Swings about the main shaft axis normally occur when a helicopter powers up or down due to the torque of the motor and rotor blades.
A gyro is a device used to correct such unwanted swings and is normally attached electronically in between the tail servos that control tail pitch and the receiver. A sensor, either mechanical or peizio in nature, will measure unwanted change in yaw of the aircraft and will correct the situation by increasing or decreasing the tail rotor pitch to stabilize the movement.
Flying a helicopter without a gyro will definitely be a handful and quite a challenge even to more experienced pilots.

Piccoz Helicopter

Picooz Heli

Geez! Have you seen the size of this little helicopter? It measures only about 6.5 inches in length and the all up flying weight is about 10 grams!

I would love to have purchased one of this if I don’t already have an electric chopper that does the works! Anyway this little toy is cool. Why? Coz u can fly it in confimed spaces without having the fear of breaking anything! I heard that this little thing can take whacks after whacks. That might be true but I do wonder how long the motors will be able to last? The last few choppers I had with brushed motors, they seem to burn out after a short period. If only they have brushless motors in these little buggers!

Anyway here are some specs and details on the Piccoz Heli by Silverlit. I wonder if that is the only brand out there. Anyway I heard they sell these things at Toys’R’Us but I personally saw it at this gadget shop at 1-Utama LG floor for about RM149.00 or so. Well its cheap for a flying chopper but all you get is 2 channels for left / right yaw and up / down motion. Hey what do you expect for something this cheap! I’d purchase it any day but unfortunately I’ve gotta save up for a TREX SE.

Picooz in your PalmProduct Dimensions
Length 170mm (6.5″)
Main Rotor diameter 130mm (5.25″)
Rear Rotor diameter 30mm (1.25″)
Product Weight Only 10g!

Details
Rechargeable Flight Battery
High capacity integral Lithium Polymer battery Charging
Integral Transmitter/Charger supplied with LED indicator/Auto shut off
Picooz Controller20-30 minutes for full charge Flight Duration
Up to 15 minutes between charges Control
Supplied completely assembled, ready-to-fly
Proportional Infra Red Control System Frequency
Infra Red Control System
Up to 3 Helicopters to fly together
Range About 100 Feet for the Transmitter Which Doubles As The Helicopter Charger

Go go gadget gadget!

We all love gadgets! And I’m sure there are many sites out there that tells us all about the nifty little gadgets out there. Well this is my little contribution to highlight which gadgets I think are cool and which ones I think are silly. Basically if they’re worth a mention, I’ll pen it down here!