Question id 84 - Flight Planning and Monitoring - ATPL - Airline Transport Pilot license

Flight Planning and Monitoring - When completing Item 9 of the ATC flight plan, if there is no appropriate aircraft designator, the following should be entered:
The most descriptive abbreviation
'XXXX' followed by an entry in Item 18
'NONE'
'ZZZZ' followed by an entry in Item 18

Training tests and timed exam simulations ATPL - Airline Transport Pilot license