How does a helicopter change direction during forward flight?

A helicopter changes direction during forward flight primarily by tilting the main rotor disk. When the pilot wants to turn, they use the cyclic control stick to change the angle of the rotor blades as they rotate. By tilting the rotor disk in the desired direction of travel, the lift vector also tilts, allowing the helicopter to move sideways or forward in that direction.

This tilting action essentially shifts the lift force towards the side, enabling the helicopter to pivot and move at an angle determined by the amount of tilt. As a result, the helicopter can effectively change its flight path and direction smoothly.

In contrast, adjusting the tail rotor speed primarily helps control yaw and stabilize the helicopter, rather than directing forward flight. Increasing altitude can be a response to various flight conditions but does not directly influence the change of direction. Finally, changing the center of gravity could affect stability and handling, but is not the primary method by which direction is altered during flight.