Definition
A calculated time, assigned by air traffic control, at which an arriving aircraft is expected to cross a designated outer fix on a published arrival route into a terminal area. It is used by ATC to sequence and meter arrivals so traffic flows smoothly into the approach environment.
Plain English
The time ATC wants you to be over a specific point on your way into a busy airport, used to space arriving aircraft so they don't all reach the runway at once.
Context Anchor
You may encounter this term in ATC arrival planning, traffic management, holding, or metering into a busy airport area.
Derivation
"Outer fix" combines "outer" (further from the airport) with "fix" (a specific named point in space defined by navigation references). Adding "time" gives the controller's target crossing time for that point. Knowing it's the further-out reference point helps clarify that this is a sequencing tool used well before the approach itself.
Why Pilots Care
Helps pilots plan descent, speed adjustments, and fuel for sequenced arrivals.
Intuition Check
Do not read “fix” here as repairing something. In aviation, a fix is a known point in the sky or on a route that pilots and controllers use for navigation and timing.
Example Sentence 1
Center assigned an outer fix time of 1422Z, so the crew reduced speed slightly to cross the fix on schedule.
Example Sentence 2
The crew reduced speed slightly to meet the outer fix time without holding.