Who is responsible for ensuring that an installed instrument is properly marked?

Who is responsible for ensuring that an installed instrument is properly marked?

• A. The mechanic installing the instrument
• B. The pilot
• C. The owner
• D. The maintenance supervisor

Answer: (A)

The installer is responsible for proper marking because labeling is part of the installation process and provides essential traceability. When the instrument is put in place, the mechanic must ensure it is correctly identified—capturing the instrument type, part number or serial, installation location, and any calibration or maintenance data. This labeling and documentation stay with the instrument so future maintenance can verify its identity and calibration status, keeping the aircraft’s airworthiness intact. The pilot, owner, or supervisor may handle operation or oversight, but the person performing the installation is the one who ensures the marking is correct and complete.

The installer is responsible for proper marking because labeling is part of the installation process and provides essential traceability. When the instrument is put in place, the mechanic must ensure it is correctly identified—capturing the instrument type, part number or serial, installation location, and any calibration or maintenance data. This labeling and documentation stay with the instrument so future maintenance can verify its identity and calibration status, keeping the aircraft’s airworthiness intact. The pilot, owner, or supervisor may handle operation or oversight, but the person performing the installation is the one who ensures the marking is correct and complete.