Definition
A condition in which the aircraft is tracking the published or assigned course toward a fix, navaid, or runway, with the course needle centered (or within tolerance) and the heading set to maintain that track. Used in instrument procedures to confirm the aircraft is on the inbound segment of an approach, holding pattern, or course to a fix.
Plain English
The aircraft is flying along the correct course toward the fix or runway, lined up properly, not still turning onto it or correcting back to it.
Context Anchor
Seen in instrument flying when joining an approach course, a holding pattern inbound leg, or a course to a fix after being cleared direct.
Derivation
Established' comes from Latin stabilire, 'to make firm or steady.' In flying, it means the aircraft is firmly settled on the course, not still maneuvering to capture it. 'Inbound' simply means heading toward the reference point (the fix, navaid, or runway).
Why Pilots Care
Confirms the aircraft is properly positioned to begin final descent and continue the approach safely.
Intuition Check
Established does not mean the airplane is perfectly centered every second. It means the aircraft has actually joined the intended inbound path and is tracking it toward the correct point.
Example Sentence 1
Once established inbound on the final approach course, the pilot reduced power and began the descent to the next stepdown altitude.
Example Sentence 2
Report established inbound when tracking the final approach course inbound to the runway.