Definition
A notification displayed to an air traffic controller on the En Route Decision Support Tool (EDST) indicating that the route filed by a pilot is not the route ATC prefers for that flight, and prompting the controller to consider issuing the preferred route. EDST is the controller's flight data and conflict-probe display used in en route ATC facilities (ARTCCs).
Plain English
It is an alert on the controller's screen that says, 'The route this aircraft filed isn't the one we'd rather use — here's the better one.' The controller can then decide whether to issue that preferred route to the pilot.
Context Anchor
Seen in FAA glossary and air traffic control automation discussions, especially where en route controllers review or change flight routes.
Derivation
EDST stands for En Route Decision Support Tool — a computer system that helps en route controllers manage flights. 'Preferred route' refers to a route ATC has predetermined as efficient for traffic flow between two points. The full term simply names the on-screen notification that flags a mismatch between filed and preferred routing.
Why Pilots Care
Following the notified route reduces airborne holding, minimizes fuel burn, and helps maintain schedule reliability.
Intuition Check
Do not read “preferred” as optional or merely nicer. In this context, it means the route ATC wants used for traffic flow, and the pilot follows it only when ATC issues it as a clearance.
Example Sentence 1
Center issued us a full route clearance shortly after handoff, likely because an ATC preferred route notification had appeared on the controller's EDST display.
Example Sentence 2
The pilot received a reroute clearance that originated from an ATC Preferred Route Notification Edst processed by the sector team.