If radar contact is lost and then regained after 30 seconds, what must be done?

When radar contact is lost and subsequently regained, it is essential to re-establish radar contact with the pilot. This process ensures that there is clarity and continuity in communication, as well as a solid understanding of the aircraft's situational awareness. The key reason for re-establishing radar contact lies in the need to verify the aircraft's current position, altitude, and intentions after a period of lost contact. Given that 30 seconds can be significant in a dynamic airspace, it’s crucial to ensure that all pertinent information is updated and that the aircraft is correctly tracked.

While informing the pilot that contact was lost might be an action taken as part of the communication process, it does not address the primary requirement of ensuring that the radar data is current. Similarly, advising the pilot solely about their altitude fails to provide a comprehensive check on the aircraft's overall status. Moreover, although there might be scenarios where no immediate action is necessary, re-establishing radar contact is a standard procedure that prioritizes safety and operational integrity in aviation.