Definition
The published calendar date on which a navigation database revision becomes valid for operational use. Before this date, the previous revision remains in effect; on and after this date, the new revision is the authoritative dataset for flight planning and navigation.
Plain English
The date the new version of the navigation database officially takes over from the old one.
Context Anchor
Seen with navigation database updates, instrument procedure changes, and other published aviation revisions that become valid on a specific date.
Derivation
From Latin effectivus, 'producing a result.' In this context, it marks the date the revision starts producing its result — that is, the date it becomes the data the aircraft and pilot must rely on.
Why Pilots Care
Pilots must confirm this date before flight planning to ensure they operate with current, legally required data and avoid using superseded procedures.
Grounding Statement
If the effective date has not arrived yet, use the current version; once that date arrives, use the revised version.
Intuition Check
Effective does not mean the revision is more powerful or more important. Here, effective means the date when the revision becomes valid for use.
Example Sentence 1
Before the cross-country flight, the pilot confirmed the FMS database's effective date of the revision covered the day of the trip.
Example Sentence 2
Before departure the pilot verified the effective date of the revision matched the installed database cycle.