Helicopter Flight Controls

Helicopters are affected by aerodynamics in the same way airplanes do, only helicopters can't glide. A helicopter is what's known as a rotor wing aircraft. It uses a set of symmetrical airfoils or rotor blades to produce lift. Those same blades are also used to control pitch and roll. There are a few different types of helicopters, depending on the intended use. But I am talking about a traditional helicopter, containing a main rotor and vertical tail rotor. So, we know that the main rotor produces lift, thrust, and controls movement around it's lateral and longitudinal axis. To aid in pitch control and to provide stability in forward flight the helicopter uses a horizontal stabilator. For movement around the vertical or yaw, helicopters depend on the use of a much smaller, vertically positioned tail rotor. When in a hover or forward flight, when the tail rotor blades are in the rigged neutral position, the tail rotor is counteracting the torque produced by the engines turning the blades. The tail rotor becomes what is a rudder in an airplane by varying pitch of the tail rotor blades. Increasing pitch pulls the tail in the opposite direction of the rotation of the main rotor. The flight control system is the most delicate, and complex part of the aircraft. The helicopter is controlled by a cyclic stick, collective stick, and yaw pedals. The connection between the pilot's controls and the rotor head is all mechanical. Through rods, bellcranks, links, levers, torque shafts, hydro-mechanical servos, a maze of parts called a mixing unit, and finally to the swashplate, the component that transmits the control inputs to the rotor blades. The tail is controlled in a similar way except from the mixing unit to the tail, cables are used to control the tail rotor servo, which transmits inputs to the tail rotor blades. All of these components must be