How to Choose an RC Helicopter
Remote control helicopters are just about the most complicated RC models there are (we will start as we mean to go on, and avoid referring to them as toys!) There are just so many moving parts operating at the same time. Even if you are familiar with RC fixed wing craft (airplanes) you will soon see that flying an RC helicopter is a whole new ball game.
Although there are different ways of powering an RC chopper, the one most newcomers will come across is battery power. This is because practically all RTF (ready-to-fly) helicopters are electric, and they are sold everywhere. They're also cheap. Since an RTF craft is definitely best for a beginner, that is what we'll discuss here.
That being said, apart from the power source, method of starting the engine etc, RC helicopters are all pretty much alike in terms of how they fly. And they fly pretty much the way a full-size helicopter does. How easy they are to fly, depends on how the rotors operate.
A helicopter lifts off the ground by rotary motion. Straightaway you can see that, with just one rotor spinning, the body of the craft will want to spin in the opposite direction. This is called torque. To avoid this happening another rotor must be introduced, spinning in the opposite direction. If you now apply the throttle, the helicopter will lift off the ground in a straight line.
RC helicopters are controlled by means of a transmitter, which sends signals to the receiver, which then transmits them to various electronic servos and, in hobby-grade models, a gyro (on the tail end) Hobby-grade is anything that is not a 2 channel toy. Toys are for little kids. As a novice pilot, you will start on 3 channel or above.
RC helicopters can be one of two types - single rotor or co-axial. Single rotor craft are further divided into fixed-pitch (FP) or collective-pitch (CP) helicopters. Pitch relates to the way the main rotor is controlled. On fixed pitch craft, the rotor cannot be angled in any way, and lift is achieved by throttle alone. On CPs, lift is achieved by a combination of pitch control and throttle.
The fixed pitch RC helicopter normally has a 4 channel receiver; the CP 5 (more commonly, 6.) This makes collective pitch helicopters incredibly manoeuvrable - but totally unsuited to beginners. 4 channels are quite enough to be going on with.
But what are all the controls for? Well, keeping to a basic 4 channel fixed-pitch model, first there's the throttle. But on its own, that only lifts the helicopter up and down. At some point you will want to stop rising and go into hover mode - that's where the tail rotor comes in. Then, you will want to go forward and back, roll side-to-side and do all the other exciting things helicopters do in the air. For that, you need fore-and-aft and side-to-side cyclic controls.
Hopefully, you will see by now that even piloting a simple fixed-pitch radio control helicopter is a tricky thing to master. To steer, you first have to hover. To hover, you have to co-ordinate the two rotor blades. Get it wrong, and you're picking bits of shattered E-sky mainframe out of your hair.
