In the ATC flight plan Item 19, if the number of passengers to be carried is not known when the plan is ready for filing: - ATPL

Question id 94 - Flight Planning and Monitoring - ATPL - Airline Transport Pilot license

An estimate may be entered but that number may not subsequently be exceeded

The plan should be filed with the relevant box blank

The plan may not be filed until the information is available

'TBN' (to be notified) may be entered in the relevant box