What does Precision Runway Monitoring (PRM) refer to?

Precision Runway Monitoring (PRM) refers specifically to a radar system designed to monitor aircraft approaches to closely spaced parallel runways. This system enhances safety by providing air traffic controllers with precise information about the positions of aircraft making simultaneous approaches to parallel runways that are closer together than standard spacing would typically allow.

PRM utilizes advanced radar technology that can track and display the paths of multiple aircraft, ensuring that controllers can maintain safe separation as each plane approaches its designated runway. The capability to handle these closely spaced runways is crucial, particularly at busy airports where maximizing runway usage is essential for efficiency and reducing delays.

While other options mention aspects of radar systems, they do not accurately capture the specific function and application of PRM. For instance, monitoring landings at uncontrolled airports or general instrument landings does not reflect the unique operational characteristics associated with closely spaced parallel runway configurations. Therefore, option C accurately describes the intended purpose and operational context of Precision Runway Monitoring.