Helicopters Radio controlled helicopters seem to be enjoying an ever-growing base of popularity and a rapidly expanding range of sizes and variations from tiny indoor micro helis to large petrol and turbine powered monsters. The most prolific and established segment of the spectrum is the .30 to .90 range, so named after the (nitro) engine size they are powered by. There are electric counterparts to these sizes as well as a large range of smaller electric machines.

The better machines utilize rotor designs and mechanics that very closely mirror full-sale aircraft and make possible amazing agility in flight. The large community of heli flyers has enabled very high precision machined components to become widely available and extremely affordable.

The helicopters pictured below are fairly typical of their respective size classes and feature full cyclic and collective pitch, belt-driven tail rotors with heading-hold gyros to stabilize the tail making them capable of a staggering array of aerobatic maneuvers as well as very precise sport or scale style flying.