Airborne Collision Avoidance System: Keeping You Safe Skies

Soaring through the sky, freedom beckons. But nestled beneath the thrill lies a hidden danger: mid-air collisions. Fear not, intrepid traveler! The Airborne Collision Avoidance System (ACAS) acts as your silent guardian angel, constantly scanning the heavens for potential threats.

How It Works:

  • ACAS tracks nearby aircraft using their transponders.
  • If a potential collision is detected, ACAS issues alerts and instructions to pilots.
  • These instructions, called Resolution Advisories (RAs), guide pilots on how to avoid the danger.

Two Main Types:

  • ACAS I: Provides traffic advisories (TAs) informing pilots of nearby aircraft.
  • ACAS II: More advanced, offering TAs and RAs to actively prevent collisions.
TCAS – Traffic Collision Avoidance System


  • Reduces risk of mid-air collisions.
  • Enhances situational awareness for pilots.
  • Improves overall air traffic safety.

Next Generation ACAS:

ACAS technology is constantly evolving. Newer versions offer improved accuracy, range, and capabilities.

Soaring Safely:

ACAS is a crucial safety feature in modern aviation, working tirelessly to keep you safe every time you take to the skies.

Further Reading and Reference Links:

Official Resources:

Federal Aviation Administration (FAA) – link
Eurocontrol – link
SKYbrary Aviation Safety – link

Articles and Publications:

(ACAS) Guide: https://www.eurocontrol.int/publication/airborne-collision-avoidance-system-acas-guide
Wikipedia: https://en.wikipedia.org/wiki/Airborne_collision_avoidance_system

Additional Resources:

Portable Collision Avoidance System (PCAS): https://en.wikipedia.org/wiki/Portable_collision_avoidance_system
FLARM: https://www.flarm.com/