What has priority for stab trim?

What has priority for stab trim?

• A. Pilot trim
• B. Autopilot trim
• C. Auto trim
• D. Mach trim

Answer: (A)

Manual input from the pilot has priority for stabilizer trim. Stabilizer trim sets the airplane’s pitch balance by changing the horizontal stabilizer angle to reduce control forces and keep the aircraft trimmed as speed, weight, configuration, and flight conditions change. The autopilot can trim to maintain its commanded attitude, and automatic trim systems help as well, but when the pilot moves the trim, that input takes precedence. This gives the pilot direct, immediate control and the ability to override automation if needed, such as in abnormal situations or during transitions. Mach trim and other automatic trimming assist the system, but they do not override the pilot’s trim command.

Manual input from the pilot has priority for stabilizer trim. Stabilizer trim sets the airplane’s pitch balance by changing the horizontal stabilizer angle to reduce control forces and keep the aircraft trimmed as speed, weight, configuration, and flight conditions change. The autopilot can trim to maintain its commanded attitude, and automatic trim systems help as well, but when the pilot moves the trim, that input takes precedence. This gives the pilot direct, immediate control and the ability to override automation if needed, such as in abnormal situations or during transitions. Mach trim and other automatic trimming assist the system, but they do not override the pilot’s trim command.