What is a transponder in aviation?

What is a transponder in aviation?

• A. A transponder in aviation is a radio that sends out a unique code to air traffic controllers. This code helps controllers identify and track the airplane's location, altitude, and other important information on their radar screens.
• B. A navigation satellite
• C. A type of engine indicator
• D. A ground radar station

Answer: (A)

In aviation, a transponder is an onboard radio beacon that responds to radar interrogations from air traffic control. When ATC radar sends a signal, the transponder replies with a code that identifies the aircraft, and in many modes it also provides altitude information. This response lets controllers see which airplane is on their radar and track its position and altitude, improving spacing and safety. The system works with secondary surveillance radar, which relies on the transponder’s reply rather than just the radar echo from the aircraft. There are different modes, such as one that transmits an identity code, another that adds altitude, and more advanced modes that provide additional data. This is why the description of sending a unique code to air traffic controllers to identify and track the airplane is the best fit. It’s not a navigation satellite, not an engine indicator, and not a ground radar station.

In aviation, a transponder is an onboard radio beacon that responds to radar interrogations from air traffic control. When ATC radar sends a signal, the transponder replies with a code that identifies the aircraft, and in many modes it also provides altitude information. This response lets controllers see which airplane is on their radar and track its position and altitude, improving spacing and safety. The system works with secondary surveillance radar, which relies on the transponder’s reply rather than just the radar echo from the aircraft. There are different modes, such as one that transmits an identity code, another that adds altitude, and more advanced modes that provide additional data. This is why the description of sending a unique code to air traffic controllers to identify and track the airplane is the best fit. It’s not a navigation satellite, not an engine indicator, and not a ground radar station.