How is the pitch (angle of attack) of a helicopter rotor blade controlled?

How is the pitch (angle of attack) of a helicopter rotor blade controlled?

How does a helicopter control the pitch (angle of attack) of its rotor blades?

Answer:

The pitch of a helicopter's rotor blade is controlled by a device called a swashplate, which translates the pilot's inputs into motion of the rotor blades.

The pitch is increased or decreased uniformly by adjusting the collective, and the cyclic control allows for horizontal movement by changing the blade pitch cyclically.

Helicopters use a mechanism known as a swashplate to control the pitch, or angle of attack, of the rotor blades. This device is essential for translating the movements of the pilot into adjustments of the rotor blades to control the helicopter's altitude and direction.

The swashplate consists of two parts: the upper swashplate and the lower swashplate. The upper swashplate is connected to the helicopter controls and can tilt or move vertically. By adjusting the position of the upper swashplate, the angle of the rotor blades can be changed, thus controlling the pitch of the blades as they rotate.

When the pilot manipulates the collective control, the entire swashplate moves, causing the pitch of all rotor blades to change uniformly. This collective control is responsible for adjusting the lift generated by the rotor blades, allowing the helicopter to ascend or descend.

In addition to the collective control, helicopters also use cyclic control to enable horizontal movement. The cyclic control adjusts the pitch of the rotor blades cyclically during rotation, allowing the helicopter to tilt and move in different directions.

Therefore, the combination of swashplate, collective control, and cyclic control plays a vital role in controlling the pitch of a helicopter's rotor blades and ensuring precise flight maneuvers.