In the context of aviation and aerospace, an "Air Data System" or "Air Data Computer" (ADC) is a critical system that provides vital information about the aircraft's flight environment. The primary function of an Air Data System is to measure and calculate various atmospheric parameters, such as:

1. Static Air Temperature: The temperature of the surrounding air.
2. Static Pressure: The atmospheric pressure at the aircraft's location.
3. Total Air Temperature: The temperature of the air as it enters the aircraft's pitot system.
4. Mach Number: The ratio of the aircraft's speed to the speed of sound.
5. Barometric Altitude: The altitude above sea level, calculated from the static pressure.
6. Density Altitude: The altitude at which the air density is equivalent to the current conditions.
7. Air Density: The mass per unit volume of the air.
8. True Airspeed: The speed of the aircraft relative to the surrounding air.

The Air Data System typically consists of the following components:

1. Pitot Tube: Measures the total air pressure (dynamic pressure + static pressure).
2. Static Ports: Measure the static air pressure.
3. Temperature Sensors: Measure the temperature of the air.
4. Air Data Computer (ADC): Processes the data from the sensors and calculates the various atmospheric parameters.

The Air Data System provides essential information to the aircraft's flight control systems, autopilot, and navigation systems. This data is used to:

1. Calculate aircraft performance: Climb rate, descent rate, and range.
2. Determine navigation: Position, velocity, and altitude.
3. Control autopilot systems: Maintaining altitude, heading, and airspeed.
4. Warn of potential hazards: Such as icing conditions, turbulence, or low air density.

In summary, the Air Data System is a critical component of modern aircraft, providing accurate and reliable data on the flight environment, which is essential for safe and efficient flight operations.