Helicopter Controls:What They Do & How They Work

Cyclic, Collective, Throttle and Pedals on Rotary Aircraft

Dec 9, 2008

All helicopters have four main controls - the cyclic or stick, the collective or lever, the throttle, and the yaw pedals. An instructor explains what each of them does.

Every helicopter, no matter how large or small, how simple or complex, works in a similar way. Each machine has four main controls: the cyclic (stick), collective (lever) throttle and yaw pedals. Each control affects the helicopter’s movement in a different way, and the four all affect each other. This is a brief account of how it all works.

The Cyclic or Stick

The cyclic is a vertical stick in front of the pilot, or in the case of the Robinson R22 and Robinson R44, it is a stick between the two pilots with a T-bar across the top which enables the control to be used from either seat. Both versions work the same way, and the pilot operates the cyclic with his or her right hand.

The cyclic alters the attitude and airspeed of the helicopter. It does this by tilting the 'rotor disc', which is the hypothetical disc which the rotors make when they are turning. Moving the cyclic forward means the rotor disc tilts forward. This means that the helicopter moves forward, and it also descends and speeds up. Moving the cyclic back will cause the helicopter to climb and slow down. Moving the cyclic to the left or right causes the aircraft to turn in that direction.

The Collective or Lever

The collective is on the left side of each pilot, and looks a little like a handbrake in a car. The pilot operates it with his or her left hand.

The collective controls the height of the helicopter. It does this by altering the pitch of all the rotor blades together, or ‘collectively’ – hence the name. If the collective is raised, the pitch of all the blades increases, and the helicopter will climb. If the collective is lowered, the pitch decreases and the machine descends.

The Throttle

The throttle is on the end of the collective, so that it can be operated with the pilot’s left hand.

Opening and closes the throttle controls the amount of power produced by the engine. However, in most modern helicopters there is an electronic governor which senses the position of the collective and adjusts the throttle automatically to give the amount of power required. So there is one less things for modern-day helicopter pilots to do!

The Yaw Pedals

The pilot has his or her feet on the yaw pedals. They alter the pitch of the tail rotor, and in doing so, keep the helicopter in balance, or allow it to turn when in the hover. Pressing on the left pedal will turn the helicopter left, and using the right pedal will turn the aircraft right.

Using All the Controls Together

Use of all the controls must be co-ordinated, since they all affect each other. For instance, when the cyclic is moved forward, the helicopter will move forward and speed up, but it will also descend. To maintain altitude, the pilot needs to raise the collective. When he does this, he will need to apply left pedal to prevent the helicopter yawing (or turning) to the right.

This means that learning to fly a helicopter takes quite a long time, as the student needs to acquire proficiency on all the controls, and also understand to some extent how they work. But like with any other skill practice makes perfect!

Reference

The copyright of the article Helicopter Controls:What They Do & How They Work in Aviation is owned by Helen Krasner. Permission to republish Helicopter Controls:What They Do & How They Work in print or online must be granted by the author in writing.