Definition
A former FAA service, also known as Flight Watch, that provided pilots in flight with timely, route-specific weather information tailored to the type of flight, route, and altitude. The service was discontinued in 2015, with its functions absorbed into Flight Service on the standard frequency 122.2 MHz.
Plain English
A radio service pilots used to call up while flying to get weather updates for the route ahead. It is no longer a separate service — pilots now get the same help by calling Flight Service directly.
Context Anchor
Seen in discussions of FAA external resources, Flight Service, and in-flight weather information.
Derivation
‘En route’ comes from French, meaning ‘on the way.’ ‘Advisory’ means giving advice or information. So the name simply describes what it did: giving flight information to pilots on the way to their destination.
Why Pilots Care
Gives pilots real-time weather details so they can avoid hazards and adjust routing while airborne.
Intuition Check
Do not read “advisory” as “permission” or “control.” Here, it means weather information and guidance that the pilot uses to make decisions.
Example Sentence 1
The older textbook described how pilots once contacted En Route Flight Advisory Service for updated weather along their route.
Example Sentence 2
After receiving an update from En Route Flight Advisory Service, the pilot decided to divert south.