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Helicopter Pilotage is the art of manipulating the flight controls of a Helicopter in order to achieve controlled aerodynamic Flight . FLIGHT CONTROLS A typical helicopter has three separate flight control inputs. These are the cyclic, the collective, and the anti-torque pedals. Depending on the complexity of the helicopter, the cyclic and collective may be linked together by a so-called ''mixing unit'', a mechanical or hydraulic device that combines the inputs from both and then sends along the "mixed" input to the control surfaces to achieve the desired result. Cyclic The cyclic stick is usually located in between the pilot's legs. The cyclic is so-called, because it changes the Pitch of the rotor blades cyclically, that is the pitch of a given blade will be different depending upon its position as it rotates about the rotor head. The result is to tilt the rotor disk in a particular direction, resulting in the helicopter moving in that direction. Collective The collective is usually located on the pilot's left side. The collective changes the pitch of the rotor blades collectively or all at the same time, regardless of their position. Therefore, if a collective input is made, all the blades change equally, and the result is the helicopter increasing or decreasing in altitude. Anti-Torque Pedals The anti-torque pedals are located in the same position as the Rudder pedals in an airplane, and serve a similar purpose, namely to control the direction in which the nose of the aircraft is pointed. Application of the pedal in a given direction changes the pitch of the tail rotor blades, increasing or reducing the thrust produced by the tail rotor and causing the nose to Yaw in the direction of the applied pedal. FLIGHT CONDITIONS There are two basic flight conditions which may be considered for a helicopter. These are hovering and forward Flight . Hovering Hovering is the most challenging part of flying a helicopter. This is due to the fact that while in a hover, a helicopter generates its own gusty air which acts against the Fuselage and flight control surfaces. The end result is constant control inputs and corrections by the pilot to keep the helicopter where he wants it. However, despite the actual complexity of the act itself, the control inputs themselves in a hover are quite simple. The cyclic is used to eliminate drift in the horizontal plane, that is to control forward and back, right and left. The collective is used to maintain altitude. The pedals are used to control nose direction or Heading . It is the interaction of these controls that makes hovering so difficult, since you cannot change one without having to change the other two, which will then require even more changes in a never-ending cycle of correction after correction. Forward flight For the purposes of this article, we will consider forward flight to be flight at Airspeed s in excess of 40 KIAS, as it is at this airspeed at which most Pitot-static airspeed systems become reliable. In forward flight a helicopter's flight controls behave more like that in a fixed-wing aircraft. Displacing the cyclic forward will cause the nose to pitch down, with a resultant increase in airspeed and loss of altitude. Aft cyclic will cause the nose to pitch up, slowing the helicopter and causing it to climb. The collective now becomes analogous to the throttle in an airplane. Increasing collective(power) while maintaining a constant airspeed will induce a climb while decreasing collective will cause a descent. Coordinating these two inputs, down collective + aft cyclic or up collective + forward cyclic, will result in airspeed changes while maintaining a constant altitude. The pedals serve the same function in both a helicopter and an airplane, and that is to maintain balanced flight. This is done by applying a pedal input in whichever direction is necessary to center the Balance Ball . Hazards SEE ALSO EXTERNAL LINKS
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