For non-Mode C equipped aircraft, when should you request the pilot to confirm their assigned altitude?

Requesting the pilot to confirm their assigned altitude on initial contact, unless they state it themselves, is essential for ensuring safety and operational effectiveness in air traffic control. This practice serves as a proactive measure to verify that both the controller and the pilot have a mutual understanding of the assigned altitude, which is crucial for maintaining safe vertical separation from other aircraft.

By confirming the assigned altitude at the outset of communication, controllers can quickly address any miscommunications or misunderstandings before they escalate into potential safety hazards. This initial check can help to set clear expectations and ensure that the flight is operating as intended, particularly for non-Mode C equipped aircraft, which may lack automatic altitude reporting capabilities.

During other phases, such as after deviating from an assigned flight path, only during the approach phase, or when radar coverage is lost, altitude verification is also important, but it is not as critical as at the point of initial contact. By addressing these confirmations upfront, air traffic controllers can help mitigate risks associated with altitude discrepancies throughout the flight.