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What is the effect of the cyclic stick movement on the helicopter?
  • A
    It alters the rotor disc attitude.
  • B
    It causes an equal pitch change on all blades together.
  • C
    It alters the amount of total rotor thrust.
  • D
    It changes the coning angle.

Refer to figure.
The three basic controls of helicopters are:

  • Cyclic control
  • Collective control
  • Tail rotor control

Cyclic control is the primary control used to change the direction of flight in a helicopter typically located on the pilot's stick or joystick and it works in coordination with the collective control to change the helicopter's direction and altitude.

The cyclic control alters the pitch of the main rotor blades at different points around the rotor disk by tilting the swashplate assembly.

When a cyclic control input has been made, the rotor blade pitch will be increasing for one half of a revolution and decreasing for the next half and as a result it alters the rotor disc attitude.

Change of the rotor disc attitude means that a horizontal component of the Total Rotor Thrust is generated. When cyclic control is applied to a direction, then the rotors disc tilts to the same direction and the horizontal component of the Total Rotor Thrust is pointing to the same direction as well, providing the driving force for horizontal motion at the corresponding direction.


NOTE:
Cyclic control does not alter the magnitude of the Total Rotor Thrust, only the rotor disc attitude.

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