Definition
An aircraft equipment suffix, appended to the aircraft type on an IFR flight plan, indicating that the aircraft is equipped with a GPS (or GNSS) navigation system that meets the FAA's required performance standards for IFR use, in addition to a Mode C transponder.
Plain English
A code you put on your flight plan, right after the aircraft type, that tells ATC your airplane has an approved GPS for IFR flying and a transponder that reports altitude.
Context Anchor
Seen on IFR en route low altitude charts next to published route altitudes.
Derivation
The letter 'G' was chosen as shorthand for GPS. The FAA assigns single-letter equipment suffixes (A, B, G, R, W, etc.) so a flight plan can quickly tell ATC what navigation and surveillance gear is on board.
Why Pilots Care
It confirms whether GPS navigation can be used to that fix and whether the aircraft’s GPS equipment must be operational for the route segment.
Intuition Check
The G does not mean “ground” or “general.” On this chart, it points to GPS/GNSS use for that published altitude.
Example Sentence 1
She filed her Cessna 182 as C182/G because the airplane has a panel-mounted IFR-approved GPS and a Mode C transponder.
Example Sentence 2
When reviewing the low altitude chart for an IFR flight, the presence of a G suffix on several fixes confirms GPS routing is available.