Final answer:
Pitot/static instruments such as the pitot tube, static port, and airspeed indicator all have cases that are connected to the static port. The difference between these instruments lies in their specific functions and how they measure different aspects of air pressure and speed.
Step-by-step explanation:
The three pitot/static instruments, namely the pitot tube, the static port, and the airspeed indicator, all have cases that are connected to the static port. However, what creates the difference between these instruments is their specific functions and how they measure different aspects of air pressure and speed.
The pitot tube is designed to measure the dynamic pressure or the difference between the total pressure and the static pressure. It is used to determine the aircraft's airspeed and is commonly found on the aircraft's nose. The pitot tube has both an opening facing forward to measure the dynamic pressure and one or more openings on the side for static pressure.
The static port is used to measure static pressure, which is the atmospheric pressure in a non-moving air mass. It is typically located on the side or underside of the aircraft, away from any air disturbances caused by the aircraft's movement. The static port provides a reference point for the pitot tube and other instruments.
The airspeed indicator is connected to both the pitot tube and the static port. It uses the difference between the dynamic and static pressure to display the aircraft's airspeed. As the aircraft moves through the air, the pressure difference causes the airspeed indicator to display the corresponding speed.