airborne collision avoidance system

airborne collision avoidance system

[′er‚bȯrn kə′lizh·ən ə′vȯid·əns ‚sis·təm] (navigation) A navigation system for preventing collisions between aircraft that relies primarily on equipment carried on the aircraft itself, but which may make use of equipment already employed in the ground-based air-traffic control system. Abbreviated ACAS.

airborne collision avoidance system (ACAS)

Typical function block diagram of airborne collision avoidance system.An aircraft system based on SSR (secondary surveillance radar) transponder signals which operates independently of ground-based equipments to provide advice to the pilot on potential conflicting aircraft that are equipped with SSR transponders (ICAO). The system alerts the pilot to conflicting air traffic.