When should you declare minimum fuel to the controlling agency?

Declaring minimum fuel is an important communication to ensure that air traffic control is aware of the aircraft's fuel status and can provide the necessary assistance. The correct timing for making this declaration is when the fuel remaining at final touchdown is below the minimum requirements. This is critical because it informs the controlling agency that the aircraft may not have enough fuel for a go-around or extended holding, thereby requiring priority handling for landing. This declaration helps air traffic control to manage the airspace effectively and may influence their decisions regarding sequencing and clearance for other aircraft.

While declaring minimum fuel is also relevant at other points during the flight, such as when airborne or when entering the traffic pattern, the most crucial moment to communicate this status is immediately prior to landing, when the fuel situation is most critical. Making the declaration too early or at cruising altitude does not effectively convey the imminent need for landing priority associated with low fuel levels.