Definition
Specific IFR routings established by the FAA between busy airport pairs to standardize traffic flow, reduce controller workload, and improve the likelihood that a flight plan will be accepted as filed. They are published in the Chart Supplement and are divided into low-altitude and high-altitude routes.
Plain English
These are the routes that air traffic control would prefer you fly between certain busy airports. If you file one of them in your flight plan, you are much more likely to get exactly the clearance you asked for, instead of a re-route.
Context Anchor
Seen during instrument flight planning when choosing what route to file, often in FAA flight planning publications or electronic planning tools.
Why Pilots Care
Filing a preferred route often results in faster flight plan approval and fewer enroute changes.
Intuition Check
“Preferred” does not mean the pilot’s personal favorite route here. It means a route that air traffic control prefers or commonly uses for managing traffic.
Example Sentence 1
Before filing IFR from Chicago to New York, she checked the Chart Supplement for a preferred route between the two airports.
Example Sentence 2
Using the preferred route between these airports helped the flight receive clearance without delay.