Which of the following is NOT a pitot-static instrument?

• A. Altimeter
• B. Airspeed indicator
• C. Vertical speed indicator
• D. Gyro compass

Answer: (D)

Pitot-static instruments rely on sensing air pressures to indicate airspeed, altitude, and rate of climb or descent. The airspeed indicator uses the difference between dynamic pressure from the pitot tube and the static pressure to show speed. The altimeter uses only static pressure to display altitude. The vertical speed indicator tracks how static pressure changes over time to show the rate of climb or descent.

A gyro compass, however, operates on a spinning gyroscope to provide a directional reference. It’s powered separately (often by vacuum or electricity) and relies on gyroscopic properties and gravity, not on pitot or static pressure. That’s why it’s not a pitot-static instrument.