In the context of the pitot static system, what is the difference between total and static pressure called?

The difference between total pressure and static pressure in the context of the pitot-static system is termed dynamic pressure. Total pressure is the sum of static pressure and dynamic pressure, which is the pressure associated with an object’s velocity through the air.

When an aircraft moves, it experiences both static pressure—essentially the air pressure surrounding the aircraft, unaffected by its motion—and dynamic pressure, which reflects the kinetic energy of the air as it moves past the aircraft. This relationship is crucial for understanding how an aircraft interacts with the surrounding air and is foundational for various aerodynamic calculations, including lift and drag.

Dynamic pressure is mathematically expressed as half the product of air density and the square of the velocity of the airflow, indicating how the speed of the aircraft contributes to the pressures experienced during flight. Knowing this distinction is essential for pilots and engineers as it directly impacts aircraft performance and the accuracy of airspeed readings.