MMS
The MMS provides high-resolution and accurate meteorological parameters (pressure, temperature, turbulence index, and the 3-dimensional wind vector). The MMS consists of 3 major systems:
1a. The Air Motion Sensor consists of two airflow-angle probes, three total temperature probes (with different response times), a pitot-static pressure probe, and a dedicated static pressure system.
1b. Pitot-Static system- A device consisting of two parts, a pitot tube and a static port. The pitot tube is an open tube aimed into the direction of flight which allows air to flow into it thus measuring total pressure. The static port is aligned so that air flows across, not into, the port. This measures static pressure of the air. The arithmetic difference of the two measured pressures (Pt-Ps) is used to determine dynamic pressure. Static temperature is further needed to derive airspeed.
2. Total Temperature probe- device which measures Total Temperature which is due to ambient temperature plus friction effects between the airflow and the probe itself.
3a. INS- Inertial Navigation System
3b. GPS- Global Positioning System
3c. Aircraft Motion Sensor- comprised of the GPS and INS plus associated hardware. Used to determine the motion of the aircraft with respect to the surface of the earth
