What is Established?

Surprisingly, the FAA is not the place to look for a definition of established. The AIM and the Instrument Flying Handbook say nothing on the topic. Only in the Instrument Procedures Handbook (FAA-H-8261-1A) does a definition pop up, and it just says that ICAO defines established as within half-scale indication on a localizer or VOR course. Useful, but there must be more.

Editorial Staff

Monday, August 04, 2014 at 12:00 AM ET

Verified

Key Takeaways:

The FAA defines "established" on a localizer or VOR course as within a half-scale indication (per ICAO), but practical application often allows for initiating descents slightly earlier (e.g., "course alive") due to generous protected airspace.
Pilots must strictly adhere to minimum crossing altitudes at step-down fixes; while starting descents slightly before a fix (e.g., 0.2 miles) is often safe due to aircraft speed and system tolerances, it's crucial not to bust altitude restrictions.
When using GPS with "fly-by" fixes, the system anticipates turns and keeps the CDI centered during the maneuver, but pilots should wait until *abeam* the fix or until the GPS sequences to the next leg before initiating a descent for the subsequent segment.
Despite the air traffic system's design with significant safety margins that can accommodate minor procedural deviations, a precise understanding of "established" and correct timing for altitude changes is essential for pilot proficiency and regulatory compliance.

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We’ve all heard “Maintain … until established.” We fly the route and make our descents without ATC yelling (usually). But are we actually doing it right?
Surprisingly, the FAA is not the place to look for a definition of “established.” The AIM and the Instrument Flying Handbook say nothing on the topic. Only in the Instrument Procedures Handbook (FAA-H-8261-1A) does a definition pop up, and it just says that ICAO defines “established” as within half-scale indication on a localizer or VOR course. Useful, but there must be more.