What is the role of the "transponder mode C"?

The role of "transponder mode C" is to provide altitude reporting to Air Traffic Control (ATC). When activated, transponder mode C transmits the aircraft's altitude information along with its identity and position to ATC radar systems. This capability allows air traffic controllers to maintain an accurate picture of traffic in the airspace, facilitating safe aircraft separation and efficient traffic management.

Transponder mode C is particularly important because it enhances situational awareness for ATC and helps in ensuring the safety of all aircraft operating in their jurisdiction. By relaying precise altitude data, it allows controllers to make informed decisions about altitude assignments and traffic conflicts.

In contrast to other options, communicating directly with nearby aircraft, recording flight hours, or enhancing navigational capabilities are not functions of transponder mode C. These roles involve different systems or protocols not specifically associated with the altitude reporting function that mode C provides.