Definition
In FAA usage, a facility, system, navigational aid, or service is described as operational when it has been commissioned and is in service, available for use within its published parameters. The term indicates that the item is functioning and may be relied upon, as distinct from being out of service, unmonitored, or under test.
Plain English
It is up and running, and you can use it as published.
Context Anchor
Seen in airport, equipment, aircraft system, and air traffic control discussions when deciding whether something can actually be used.
Derivation
From Latin opus, operis meaning 'work,' through operari 'to work or function.' In aviation it carries the sense of 'working as intended and in active service' — not just capable of working, but actually placed in service for use.
Why Pilots Care
Knowing what is operational helps pilots confirm what equipment, procedures, or responsibilities are actually available and in effect during a flight.
Intuition Check
Operational does not just mean “related to operations.” In aviation use, it usually means working, active, and available to use.
Example Sentence 1
The NOTAM confirmed that the runway 27 approach lighting system was operational, so we briefed the full ILS approach.
Example Sentence 2
Only operational navigation aids may be used when planning an IFR route.