all flights; entire fleet
Refers to every flight or the whole fleet of aircraft, often in contexts of cancellations, delays, or operations.
台風のため、全便が欠航になった。
All flights were canceled due to the typhoon.
In-flight Wi-Fi is available on all flights of this airline.
all mail
Used for the entirety of mail or postal items, such as in sorting, delivery, or processing contexts.
年末は全便の配達が遅れることがあります。
Delivery of all mail may be delayed at the end of the year.