Commercial Pilot License (CPL) 2025 – 400 Free Practice Questions to Pass the Exam

The instruments that operate from the pitot/static system include the altimeter, vertical speed indicator (VSI), and airspeed indicator.

The pitot/static system is essential for providing accurate readings of altitude and airspeed in flight. The pitot tube measures dynamic air pressure, which is used specifically for the airspeed indicator to determine the aircraft’s speed through the air. Conversely, the static port measures static air pressure, which is crucial for both the altimeter and the VSI. The altimeter utilizes the static pressure to display the aircraft’s altitude above sea level, while the VSI measures the rate of climb or descent by comparing the current static pressure with the pressure at a previous instant.

In contrast, other instruments listed in the other choices, such as the heading indicator, attitude indicator, and turn coordinator, do not rely on the pitot/static system for their functions. Instead, they operate based on gyroscopic principles or magnetic axes. For example, the heading indicator uses a gyroscope to maintain orientation relative to geographic north, while the attitude indicator displays the aircraft's orientation relative to the horizon.