Definition
The formal process of permanently taking a navigation aid, instrument approach procedure, airway, or piece of aviation infrastructure out of service. Once decommissioned, the facility or procedure is no longer published, no longer maintained, and may not be used for navigation or approach guidance.
Plain English
Officially shutting something down for good. After it's decommissioned, pilots can't use it anymore and it disappears from the charts.
Context Anchor
Seen in discussions of instrument approaches when older navigation aids or procedures are being removed and replaced by newer systems or procedures.
Derivation
From the prefix 'de-' meaning to undo or reverse, plus 'commission,' which originally meant to put into active service. So 'decommission' literally means to take out of active service — the opposite of bringing something online.
Why Pilots Care
Pilots must know when aids or procedures are decommissioned to avoid attempting to use unavailable navigation facilities during flight planning or execution.
Intuition Check
Do not read decommissioning as a short maintenance delay. In this context, it means an official removal from service, not just a temporary outage.
Example Sentence 1
After the VOR was decommissioned, the approach that depended on it was removed from the chart.
Example Sentence 2
Pilots planning flights to the airport must check NOTAMs for any recent decommissioning of ground-based navigation aids.