Plain English Meaning

A small computer that takes in air pressure and temperature readings from outside the aircraft, does the math, and feeds the results to the instruments that show altitude, speed, and climb or descent rate.

Full Definition

An electronic device that receives pitot (ram) and static air pressure inputs, along with outside air temperature, and calculates derived flight parameters such as airspeed, altitude, vertical speed, and Mach number. The computed values are then sent to the cockpit displays and other aircraft systems that need them.

Context Anchor

Seen in discussions and in aircraft with or other that need calculated information.