Precession errors between which range are typically self-corrected by the erecting mechanism of the attitude indicator?

Precession errors between which range are typically self-corrected by the erecting mechanism of the attitude indicator?

• A. 0°-1°
• B. 3°-5°
• C. 6°-8°
• D. 9°-12°

Answer: (B)

Precession errors on an attitude indicator arise from gravity acting on the gyroscope’s gimbal as the aircraft tilts. The erecting mechanism is designed to automatically reorient the gyro back toward a level reference when the aircraft’s attitude is within a small range, thereby cancelling the precession effect for those small tilts. This self-correction works best for minor deviations—roughly within 3° to 5° of level. Within this window, the horizon on the instrument is maintained accurately by the mechanism. If the tilt exceeds that small range, the mechanism no longer actively corrects, and precession errors can build, so the instrument may no longer precisely reflect the actual attitude. Hence, the correct range is 3°-5°.

Precession errors on an attitude indicator arise from gravity acting on the gyroscope’s gimbal as the aircraft tilts. The erecting mechanism is designed to automatically reorient the gyro back toward a level reference when the aircraft’s attitude is within a small range, thereby cancelling the precession effect for those small tilts. This self-correction works best for minor deviations—roughly within 3° to 5° of level. Within this window, the horizon on the instrument is maintained accurately by the mechanism. If the tilt exceeds that small range, the mechanism no longer actively corrects, and precession errors can build, so the instrument may no longer precisely reflect the actual attitude. Hence, the correct range is 3°-5°.