Aircraft instrument value should be marked and graduated in accordance with

Aircraft instrument value should be marked and graduated in accordance with

• A. Pilot's preference
• B. Maintenance or flight manual
• C. Calibration schedule
• D. Manufacturer's suggested color coding

Answer: (B)

The value marks and graduations on aircraft instruments must match the official specifications laid out in the maintenance or flight manual. This documentation provides the exact scale increments, zero reference, and permissible ranges for each instrument, ensuring readings are interpreted consistently and are traceable to the instrument’s calibration. Following these guidelines supports accurate readings, appropriate maintenance actions, and compliance with airworthiness requirements. While color coding can aid quick identification and a calibration schedule indicates when checks are due, neither by itself defines the correct markings; they derive from the manual’s approved scales.

The value marks and graduations on aircraft instruments must match the official specifications laid out in the maintenance or flight manual. This documentation provides the exact scale increments, zero reference, and permissible ranges for each instrument, ensuring readings are interpreted consistently and are traceable to the instrument’s calibration. Following these guidelines supports accurate readings, appropriate maintenance actions, and compliance with airworthiness requirements. While color coding can aid quick identification and a calibration schedule indicates when checks are due, neither by itself defines the correct markings; they derive from the manual’s approved scales.