Which of the following is NOT displayed by the backup flight instruments?

• A. Attitude
• B. Airspeed
• C. Altitude
• D. Acceleration

Answer: (D)

Backup flight instruments are there to keep you oriented and aware of basic flight parameters if the primary set fails. The standard standby trio gives you orientation with the attitude indicator, shows altitude with the altimeter, and provides airspeed with the airspeed indicator. These readouts cover the fundamentals you need to control the aircraft: where you are relative to the horizon, how high you are, and how fast you’re going. Acceleration, which is how quickly your velocity is changing, isn’t a parameter that these traditional standby instruments display. They don’t include an accelerometer readout, so you wouldn’t see a direct acceleration value on the backup set. If you needed acceleration data, that would come from more specialized equipment beyond the standard backup instruments.