What device helps pilots avoid collisions in flight?

The Traffic Collision Avoidance System (TCAS) is specifically designed to assist pilots in avoiding mid-air collisions. This system actively monitors the airspace around the aircraft for nearby transponder-equipped airplanes. When it detects potential collision threats, TCAS provides visual and aural alerts to the flight crew, indicating whether to climb or descend to maintain safe separation from other aircraft.

While weather radar is important for navigating and avoiding storm systems, and Global Positioning System (GPS) aids in navigation and determining the aircraft's position, neither directly contributes to collision avoidance in the same way that TCAS does. Automatic Dependent Surveillance-Broadcast (ADSB) broadcasts an aircraft's position to air traffic control and nearby aircraft, improving situational awareness, but it does not actively signify collision threats or command evasive action the way TCAS does. Therefore, TCAS is uniquely focused on ensuring safe vertical and lateral separation from other aircraft, making it the right choice for collision avoidance in flight.