About 25,000 traffic-alert and collision avoidance system (TCAS) units aboard aircraft today protect lives worldwide during airline, cargo, business and government flights, including military missions, the U.S. Federal Aviation Administration (FAA) says in a recent advisory circular (AC) and technical report.1,2 Together, the documents provide a comprehensive guide to the latest operational capabilities, limitations and requirements of TCAS II.
In explaining the evolution of TCAS hardware and its programmed logic — now up to Version 7.1 software (ASW, 4/09, p. 34), introduced in 2010 and seeing wider service this year — the FAA also has focused on the critical roles of pilots, air traffic controllers and operators in the effectiveness of TCAS, known internationally as the airborne collision avoidance system (ACAS II).
“TCAS II is a last-resort airborne …
