Which instrument relies on the Pitot Tube?

The air speed indicator relies on the Pitot tube for its operation. The Pitot tube measures the dynamic pressure of the air that the aircraft is moving through, which is used to determine the aircraft's speed. This dynamic pressure is compared to the static pressure (measured from a separate static port) to calculate the calibrated airspeed. As air flows into the Pitot tube, it creates a pressure differential that directly translates into an airspeed reading, making it essential for understanding how fast the aircraft is traveling through the air.

While the altimeter and the vertical speed indicator also relate to aircraft performance, they do not rely on the Pitot tube for their readings. The altimeter measures altitude based on static pressure, while the vertical speed indicator uses changes in static pressure over time to show the rate of climb or descent. The NAV radio, on the other hand, is used for navigation and does not involve airflow measurements at all. Thus, the air speed indicator is specifically dependent on the Pitot tube, confirming its critical role in determining airspeed.