Describe the function of a rotorcraft cyclic pitch control.

• A. It changes blade pitch uniformly.
• B. It tilts each blade's pitch at a fixed time.
• C. It tilts the main rotor disc by changing the pitch angle of each rotor blade during its cycle of rotation, enabling directional movement.
• D. It adjusts collective pitch

Answer: (C)

Cyclic pitch control works by changing the pitch angle of each rotor blade as it travels around the disk, so the lift is different in different parts of the rotation. This creates a varying thrust vector that tilts the rotor disc, allowing forward, backward, or sideways movement. The pilot’s cyclic stick deflects a swashplate arrangement, which translates that input into a sinusoidal pitch pattern for each blade as it passes through its azimuth. This continuous, position-dependent change in blade pitch is what steers the helicopter.

This is different from adjusting pitch uniformly (collective), which changes overall thrust without steering, and from changing pitch at a fixed time or angle not tied to the blade’s position.