The rules that use the category "<flight_noun-pl>" are:

<flight_id-not_creatable-pl>

<flight_noun-pl> of <digit-pl> <specific_aircraft_type-pl>

<flight_noun-pl> of <specific_aircraft_type-pl>

<flight_type-not_creatable-pl>

<flight_noun-pl>

<specific_aircraft_type-not_creatable-sing> <flight_noun-pl>