Which instrument depends on both impact (dynamic) and static pressure?

• A. Airspeed Indicator (ASI)
• B. Altimeter
• C. Vertical Speed Indicator
• D. Attitude Indicator

Answer: (A)

The airspeed indicator relies on both impact (dynamic) and static pressure to determine what you’re moving through the air. It uses a Pitot tube to capture stagnation pressure from the air rushing into the tube and a static port to sense the ambient static pressure. The instrument measures the difference between these pressures, which is the dynamic pressure, and translates that into an indicated airspeed. As speed increases, dynamic pressure rises, causing the indicator to read higher.

The other instruments aren’t powered by both pressures. The altimeter uses static pressure alone to indicate altitude. The vertical speed indicator tracks how quickly static pressure changes over time to show climb or descent rate. The attitude indicator is a gyroscope-based instrument that is independent of the pitot-static pressures.