When may landing clearance be issued for an aircraft in LUAW position?

Landing clearance for an aircraft in a Line Up and Wait (LUAW) position is typically issued once the aircraft is aligned and ready to begin its takeoff, meaning once the aircraft has started its takeoff roll. This indicates that the aircraft is prepared to take to the runway and commence its flight.

The rationale here is that clearance for landing is generally granted when the landing aircraft has reached a point of no return, where it is committed to its landing. Thus, it’s appropriate to issue landing clearance when the aircraft is actively engaged in its takeoff roll, because by this point, air traffic control has assessed the traffic situation and determined that the arriving aircraft can land safely.

In contrast, if an aircraft has not yet started its takeoff roll, it is not yet in a position to either accept landing clearance or ensure a safe operation alongside landing traffic. Other scenarios mentioned, such as taxiing clear, being cleared by ground control, or being on final approach, do not apply to the specific conditions under which a landing clearance can be issued to an aircraft already in a LUAW position.