Definition
A class of airway established by the FAA in the United States, based on a centerline that extends from one navigation aid (or intersection) to another navigation aid specified for that airway. A Federal airway includes the airspace within parallel boundary lines 4 nautical miles to each side of the centerline, and unless otherwise specified, extends from 1,200 feet above the surface up to but not including 18,000 feet MSL. Low-altitude Federal airways based on VOR navigation aids are designated as 'Victor' airways and identified with a 'V' prefix (e.g., V23).
Plain English
A pre-defined highway in the sky, published on charts, that runs between two navigation stations. Pilots flying under instrument rules often follow these routes from one station to the next, staying within a corridor 4 miles wide on each side of the line.
Context Anchor
Seen on IFR en route charts and in ATC route clearances, especially when flying Victor airways below 18,000 feet MSL.
Derivation
Federal' because these airways are established and regulated by the U.S. federal government (the FAA), distinguishing them from other countries' airway systems or from non-published routes. The word 'airway' simply combines 'air' with 'way' (a path or route) — a path through the air, just as a highway is a path on the ground.
Why Pilots Care
Using them keeps the aircraft within ATC coverage, ensures terrain clearance, and maintains legal IFR routing.
Intuition Check
A Federal airway is not a visible lane or a tube in the sky. It is a charted route with defined protected airspace and rules around it.
Example Sentence 1
The controller cleared us direct to the VOR, then to join V23 eastbound to our destination.
Example Sentence 2
The pilot selected a Federal airway to maintain continuous navigation signal coverage during the cross-country leg.