The term for rotation about the vertical axis is:

• A. Yaw
• B. Pitch
• C. Roll
• D. Bank

Answer: (A)

Yaw is the rotation about the vertical axis. The vertical axis runs top to bottom through the aircraft, so when the nose points toward a different direction without changing its tilt or bank, that turning in heading is yaw. In a helicopter this is controlled with the tail rotor or anti-torque system using the pedals, which rotates the aircraft around that vertical line.

Pitch, by contrast, is the nose-up or nose-down rotation around the lateral axis (left-to-right axis), affecting climb or descent. Roll is the rotation around the longitudinal axis (front-to-back axis), causing the wings to tilt, which sets up a turn. Bank describes that tilt angle itself, not the rotation about the vertical axis.