Definition
A published RNAV (area navigation) route available for use by aircraft operating in the contiguous United States at altitudes from 18,000 feet MSL up to and including FL450. Q Routes require GPS or DME/DME/IRU navigation equipment and are depicted on high altitude en route charts.
Plain English
A high-altitude airway that is flown using GPS or other area navigation equipment instead of by tracking ground-based radio beacons. It runs through the upper airspace and is shown on high altitude charts.
Context Anchor
Seen on high-altitude charts, in flight plans, and in air traffic control clearances, such as “cleared via Q-42.”
Derivation
The letter Q is simply the identifier the FAA assigned to this category of RNAV route in the high altitude structure. It does not stand for a word; it is a chart-labeling convention, similar to how low-altitude RNAV routes use the letter T.
Why Pilots Care
Provides more direct routing options that save time and fuel when the aircraft has the required navigation equipment.
Intuition Check
Do not read Q as an abbreviation you need to expand. In “Q Route,” Q is the label used to identify this type of published high-altitude navigation route.
Example Sentence 1
The crew filed Q146 at FL360 from Denver to Chicago, taking advantage of the more direct routing offered by the high altitude RNAV structure.
Example Sentence 2
We filed a Q route to avoid the busy jet airways and shorten the trip by twenty minutes.