If the primary pitch trim system fails entirely, which system takes over?

If the primary pitch trim system fails entirely, which system takes over?

• A. Hydraulic trim system
• B. Secondary pitch trim system
• C. Mechanical spring trim
• D. Autopilot

Answer: (B)

When a jet’s pitch trim system is designed, it includes a backup path so you don’t lose trim control if the primary path fails. The correct backup in this case is a secondary pitch trim system that operates independently from the primary. If the main trim system loses power or fails completely, the secondary system takes over to provide the remaining trim authority needed to maintain the desired pitch. Autopilot isn’t considered the backup trim path because its role is to fly the airplane and it relies on separate trim pathways to actually adjust the surfaces. Mechanical spring trim can serve as a manual aid in some designs, but the official backup for a complete primary trim failure is the dedicated secondary pitch trim system.

When a jet’s pitch trim system is designed, it includes a backup path so you don’t lose trim control if the primary path fails. The correct backup in this case is a secondary pitch trim system that operates independently from the primary. If the main trim system loses power or fails completely, the secondary system takes over to provide the remaining trim authority needed to maintain the desired pitch.

Autopilot isn’t considered the backup trim path because its role is to fly the airplane and it relies on separate trim pathways to actually adjust the surfaces. Mechanical spring trim can serve as a manual aid in some designs, but the official backup for a complete primary trim failure is the dedicated secondary pitch trim system.