What information does a transponder provide to air traffic control?

Transponders play a crucial role in aircraft operations, particularly in enhancing the safety and efficiency of air traffic control. A transponder sends out signals that include both identification and location information about an aircraft. This typically includes a unique identifier (often a squawk code assigned by air traffic control) that helps air traffic controllers distinguish one aircraft from another, as well as altitude information, which is essential for ensuring safe vertical separation between aircraft.

By providing this identification and location data, transponders facilitate effective communication between the aircraft and air traffic control, allowing for better situational awareness and coordination within busy airspace. This information is vital for the safe navigation and management of air traffic, particularly in congested areas.

While transponders can also contribute altitude data, they primarily function to provide identification and location, making this information essential for air traffic control's effective oversight of air traffic.