The backup flight instrument provides backup indications for which primary flight instrument when the integrated avionics system fails?

• A. Primary flight instrument
• B. TCAS
• C. Engine instrument
• D. Navigation

Answer: (A)

The backup flight instrument is there to provide essential flight data for the primary flight instrument when the integrated avionics fail. It is designed to deliver independent stand-by indications of the core flight data—attitude, airspeed, and altitude—so the pilot can maintain control and situational awareness even if the main avionics go down. Typically this includes a standby attitude indicator for pitch and bank, a standby airspeed indicator, and a standby altimeter. It isn’t meant to back up TCAS, engine instruments, or navigation indicators, which are separate systems with their own backup provisions. So, the backup flight instrument provides backup indications for the primary flight instrument.