Definition
An Emergency Operating Facility (EOF) is a designated alternate site from which an air traffic control unit, flight service operation, or other aviation service can continue essential functions when its primary facility is unavailable due to fire, power loss, severe weather, equipment failure, or other disruption.
Plain English
A backup location that takes over running air traffic services when the main facility cannot be used.
Context Anchor
Seen in FAA acronym lists, airport emergency planning, and messages related to emergency response or disrupted operations.
Derivation
From the everyday phrase 'emergency operating facility' — a place set up to operate during an emergency. The term is descriptive rather than technical; knowing the words tells you what it is.
Why Pilots Care
Maintains access to flight information and services when normal operations are disrupted.
Intuition Check
Do not read EOF here as the computer term “end of file.” In this aviation context, EOF refers to an emergency coordination facility.
Example Sentence 1
After the tower lost commercial power, controllers transitioned to the EOF and continued separating traffic from the backup site.
Example Sentence 2
Pilots contacted the EOF directly when the primary tower was evacuated.