For ASR-9 and ASR-11, how much separation is needed from the radar antenna when less than 60 miles away?

For both ASR-9 and ASR-11 radar systems, a separation of 3 miles from the radar antenna is required when the aircraft is within 60 miles of the radar. This distance is established to ensure safety and to prevent interference with radar signals, which could cause issues in tracking and maintaining accurate control of air traffic.

This separation distance ensures that there is a sufficient buffer between the radar's operational area and the aircraft's proximity, minimizing the risk of potential radar signal interference or inaccuracies that could arise if an aircraft comes too close to the antenna. In air traffic management, maintaining the correct separation distance is critical for ensuring safe operations, especially in densely populated airspace where multiple aircraft may be operating simultaneously.

Therefore, the correct choice accurately reflects the guidelines set for the operation of ASR-9 and ASR-11 radar systems in relation to nearby aircraft.