The pitch term is one that I’ve seen mentioned a lot when speaking about RC helicopters, and digging a little bit I found that in fact there are fixed and collective pitch; these two terms appear whenever I read reviews about helis, and since I found myself with that exact doubt I thought it could be useful to include an explanation from the stand point of a newbie like me, hopefully this helps to clear a lot of doubts that are out there about these two concepts, also it is important to know that you must consider this when buying an RC heli, since collective pitch helicopters are for more experienced pilots than fixed pitch.
The pitch of an RC helicopter is the angle of attack of the main rotor blades, this angle of attack determines the amount of lift for the helicopter, as you can imagine the fixed pitch means that the angle of attack cannot be changed, whereas the collective pitch means that the helicopter is able to change the angle of the blades, this will determine a number of things that can be done using each type of helicopter.
Let’s go with fixed pitch first
A fixed pitch helicopter will be best for novice pilots; this is because pitch must be controlled from the transmitter so that may require extra channels, and extra channels always require extra practice and attention from the hobbyist.
Fixed pitch means that the main rotor blade has a fixed angle of attack, thus the lift that it’ll produce will depend on the spinning speed of the main rotor; this is in a nutshell how it will go up or down.
A fixed pitch helicopter is perfect for beginners since it will help the pilot to better understand the concept and get familiar with how these RC helicopters fly. Remember to ask for this when buying a toy or reading RC helicopter reviews, because it will determine how difficult it could be to fly.
Collective pitch can be a lot more fun yet a lot more challenging
A collective pitch RC helicopter is designed for what is called 3D flight, which is simply moving the heli all the way around in every direction. 3D flight is one of the most challenging and risky things to do, according with some experienced RC pilots; it could take years of practice before mastering the 3D flight, I have to say that I’ve seen this flight mode and it is very, very entertaining, but the risk of crashing the helicopter or hurting somebody exist, so it is something that has to be practiced over and over again to make sure that nobody will get hurt.
Collective pitch RC helicopters can fly upside down, which means that the landing skid is at the top while the main rotor blades are at the bottom. This is pretty amazing for me
Ok so now the fun thing, how collective pitch RC helicopters work. It is very simple in fact, and as I told you before funnier as well.
Collective pitch means that the angle of attack of the main rotor blades can be modified while flying the helicopter, also the lift will depend on the angle of attack. These helicopters can create negative pitch, which allow them to fly upside down. In collective pitch RC helicopters the angle of attack is modified by moving some connecting rods that modify the angle of each blade.
Pros and cons of fixed and collective pitch
This is a great thing to think about, because each pitch type will give a different flight experience. The main thing is that fixed pitch helicopters are simpler than collective pitch helicopters, I found a great video tutorial where a more experienced pilot explain the pros and cons of these two types of helicopters. I hope you enjoy this.
That is in a nutshell why each type could be more convenient to you depending on which type of pilot you are; I think it is a great advice to go first with a fixed pitch RC helicopter and from there jump to the collective pitch ones.
Hopefully this post clarified some of your doubts, it surely did it for me, because now I know what this pitch concept means and also how is that it affects the way the helicopter flies.
To your flight success!