TCAS only works in what range and setting?

• A. 5, 10, 20, 40; TFC
• B. 10, 20, 40; TFC
• C. 5, 15, 25; TFC
• D. 1, 2, 3; TFC

Answer: (A)

TCAS detects and monitors other aircraft within a selectable distance, measured in nautical miles. The standard range scales you can choose are 5, 10, 20, and 40 NM. The setting shown is Traffic, abbreviated TFC, which means TCAS is in Traffic monitoring mode to watch for potential conflicts with other aircraft and issue alerts as needed. That combination of ranges and the TFC setting is why this option is the best fit: it reflects the conventional TCAS range scales and its active traffic monitoring mode. Other options list nonstandard ranges, which don’t match how TCAS range is typically configured.