A helicopter in forward flight, cruise configuration, changes direction by?

In forward flight, a helicopter changes direction primarily by tilting the main rotor disk in the desired direction. This process involves utilizing the cyclic control stick, which allows the pilot to adjust the angle of the rotor blades as they rotate. When the rotor disk is tilted forward, backward, or sideways, it alters the lift vector, resulting in a change of flight path in the direction of the tilt.

As the rotor blades are angled, they produce more lift on one side and less on the other, which causes the helicopter to move in the direction where the lift is increased. This is a fundamental principle of helicopter flight dynamics, where the rotor's ability to generate thrust in various directions allows for agile maneuverability compared to fixed-wing aircraft.

The other options, while relevant to flight mechanics, do not accurately describe the primary method of directional change in forward flight. Adjusting the throttle setting affects the helicopter's power and altitude but does not directly cause directional changes. Rotating the airframe is not a standard method for changing direction; instead, it can cause changes in orientation without directly influencing the flight path. Shifting weight in the cabin might affect the center of gravity and consequently the handling characteristics, but it is not a direct means of changing direction in forward flight