Name the four rotor blade actions.

Name the four rotor blade actions.

• A. Rotation, Translation, Pitch, Yaw
• B. Rotation, Flapping, Feathering, Hunting
• C. Rate, Pitch, Roll, Yaw
• D. Spin, Flip, Tilt, Glide

Answer: (B)

In rotor blade dynamics, the blade can move in four fundamental ways: rotation, flapping, feathering, and hunting. The blade is attached to the rotor hub and rotates with the rotor about the mast—that’s the rotation. It also flexes up and down to respond to differing lift across the disc and gusts; that up-and-down motion is flapping. The blade’s angle of attack is adjusted by the collective through feathering, which changes pitch to increase or decrease lift. Finally, as the blade sweeps around, it can swing forward and backward in the plane of rotation—this lead-lag motion is called hunting. These are the primary motions the blade itself undergoes, not the aircraft’s overall attitude or other nonblade actions.

In rotor blade dynamics, the blade can move in four fundamental ways: rotation, flapping, feathering, and hunting. The blade is attached to the rotor hub and rotates with the rotor about the mast—that’s the rotation. It also flexes up and down to respond to differing lift across the disc and gusts; that up-and-down motion is flapping. The blade’s angle of attack is adjusted by the collective through feathering, which changes pitch to increase or decrease lift. Finally, as the blade sweeps around, it can swing forward and backward in the plane of rotation—this lead-lag motion is called hunting. These are the primary motions the blade itself undergoes, not the aircraft’s overall attitude or other nonblade actions.