What does weathercock stability refer to?

• A. The tendency of the aircraft to yaw into the wind
• B. Automatic stabilization of heading
• C. No yaw tendency
• D. Yaw away from the wind

Answer: (B)

Weathercock stability is the directional stability about the yaw axis, where the aircraft naturally tends to align its nose with the relative wind, like a weather vane. If a yaw disturbance occurs, the force of the wind on the vertical stabilizer creates a restoring moment that tends to turn the nose back into the wind, bringing the aircraft back to straight flight. This automatic correction—that the heading stabilizes without pilot input—is what is meant by automatic stabilization of heading. The other descriptions don’t capture this automatic restoring tendency: the important idea is that the aircraft self-corrects to maintain a stable heading by aligning with the wind.