Gyroscopes have completely revolutionized the RC helicopter industry. Before gyroscopes, RC helicopters were about as accessible as a Las Vegas club when you aren t wearing dress shoes. It took ages to learn to fly them properly, and about a million helicopters were broken in the process. Thankfully, now that we have gyros, it is possible to have a beginner helicopter that is easy and enjoyable to fly.
Gyros on RC helicopters are, funnily enough, not actually gyroscopes. They are more like accelerometers. How they work is very complicated, especially now that they are electrical instead of mechanical, but they perform one essential function that makes flying an RC helicopter much, much easier.
Yaw is a rotation to the left or right in a helicopter. Gyros detect yaw, then send a signal to the tail rotor in order to correct it. So if a gust of wind causes a helicopter to spin right, the gyroscope will correct this and dampen the amount of movement. This is very important, as it means trim adjustment basically only needs to be locked in, and then can usually stay in the same position.
There are two kinds of gyros when it comes to RC helicopters: heading hold and yaw rate. Early mechanical gyros were yaw rate gyros. This meant that they didn t completely correct, so if a gust of wind hit the tail it would still move it, but just much slower and in a way that makes it easier to control.
Heading hold gyros are what now come on most standard coaxial gyro helicopters. Heading hold gyros will actually hold the helicopter in the correct position. If a gust of wind hits the tail, the helicopter should ideally stay in the same position. This makes flying so much more straightforward, because the helicopter actually does what the pilot tells it to.
Heading hold gyros work by detecting the change in yaw then calculating the exact number of degrees the yaw has changed. It then sends a command to the tail rotor servo for that exact number of degrees and corrects. The tail does not move at all and the only changes in yaw are ones issued by the pilot.
When flying an RC helicopter, the rotors are constantly losing power because the battery is dying. Without a gyro this means that trim needs to be constantly adjusted. With a gyro this is not a problem at all and trim usually only has to be adjusted once before flying.
Kudos to all those who flew RC helicopters before the advent of gyros, it must have been tough. Thankfully today gyros are available standard on many hobby grade helicopters, and separately for those building helicopters. Beginners can now learn proper flying techniques in a much less harrowing situation.
One example of an excellent coaxial gyro helicopter is the Phantom S107. The Phantom is a micro helicopter, small enough to fit in the palm of your hand. It also comes with a USB charger and can be charged from any computer or laptop. The Phantom S107 handles incredibly well, with almost robotic precision. It also does not suffer from "ground effect", an effect that causes larger helicopters to lose control when hovering barely off the ground. The Phantom S107 makes an ideal first helicopter, is outrageously affordable, and is a riot to keep at the office.