What is the primary function of TCAS equipment?

The primary function of TCAS (Traffic Collision Avoidance System) equipment is to enhance the safety of aircraft by providing information about nearby aircraft. TCAS achieves this by interrogating the transponders of nearby aircraft to gather data on their altitude, position, and flight paths. This information allows TCAS to assess the risk of collision and, if necessary, provide resolution advisories to pilots, helping them to take preventive action to avoid mid-air collisions.

This function is critical in busy airspace where visual identification of other aircraft may not be possible, making TCAS an essential tool in modern aviation safety protocols. Other functions mentioned, such as controlling aircraft speed automatically, monitoring weather conditions, or providing navigation assistance, do not pertain to the primary role of TCAS.