What is the purpose of a transponder in aviation?

The function of a transponder in aviation is to send and receive signals about an aircraft’s position and altitude. This device is crucial for air traffic control and collision avoidance systems, as it helps to identify and monitor the aircraft's location in real-time. When an aircraft is interrogated by ground-based radar systems, the transponder responds with information that includes its unique identifier, altitude, and other relevant data.

This capability enhances situational awareness for both air traffic controllers and other aircraft, ensuring that all parties have up-to-date information on aircraft positions, which is vital for maintaining safe distances and managing air traffic efficiently. The transponder essentially plays a key role in the surveillance and tracking of aircraft, making it a critical component of modern aviation safety systems.

In contrast, other options do not accurately describe the primary purpose of a transponder. Navigation via GPS involves different technology, while recording flight data pertains to flight data recorders (FDR) rather than a transponder. Enhancing pilot visibility pertains more to cockpit instruments and external lighting rather than the function of a transponder.