What is the purpose of a "Transponder" in an aircraft?

The purpose of a transponder in an aircraft is to transmit information about the aircraft's position and altitude. This device plays a crucial role in enhancing situational awareness for both pilots and air traffic controllers. When an aircraft's transponder is activated, it sends out a unique signal that contains vital data such as the aircraft's identifier, altitude, and sometimes even speed. This information enables air traffic control radar systems to accurately track the aircraft's location and ensure safe separation from other aircraft in real time.

The transponder operates by receiving interrogations from ground-based radar systems and responding with the necessary information. This capability is essential for maintaining order in busy airspace and is a fundamental component of modern air traffic management. High standards of safety and coordination in aviation depend heavily on the effective functioning of transponders, making them indispensable for both air traffic controllers and pilots conducting flights.