Before revision: Implementations As of 2009 , the only implementations that meets the ACAS II standards set by ICAO are Versions 7.0 and 7.1 of TCAS II (Traffic Collision Avoidance System) produced by three manufacturers: Rockwell Collins, Honeywell and ACSS (Aviation Communication & Surveillance Systems; an L-3 Communications and Thales Avionics company).
After revision: Implementations As of 2022 , the only implementations that meets the ACAS II standards set by ICAO are Versions 7.0 and 7.1 of TCAS II (Traffic Collision Avoidance System) produced by Garmin, Rockwell Collins, Honeywell and ACSS (Aviation Communication & Surveillance Systems; an L-3 Communications and Thales Avionics company).