Definition
The flight plan currently loaded and engaged in the aircraft's flight management system or GPS navigator, with one waypoint identified as the active leg the aircraft is flying toward. The avionics use this loaded sequence of waypoints to provide course guidance, distance, and time information.
Plain English
The route that is loaded into the navigation system right now and being used to fly the aircraft, as opposed to one that is just stored or being planned.
Context Anchor
Seen when checking an area navigation system before or during instrument procedures, especially when confirming that the route shown in the unit matches the route the pilot intends to fly.
Derivation
Active comes from a Latin word meaning “to do” or “to act.” In this term, active means the flight plan is not just stored in the system; it is the one the system is acting on for guidance.
Why Pilots Care
Ensures the aircraft follows the correct cleared route and prevents navigation errors during instrument flight.
Analogy
It is like a phone map app: you may have several routes saved, but only the one currently navigating is the active route.
Intuition Check
Do not read active as merely “available” or “turned on.” Here, active means the flight plan the navigation system is using right now to guide the aircraft.
Example Sentence 1
Before starting the approach, the pilot confirmed the active flight plan matched the routing on the clearance.
Example Sentence 2
A waypoint mismatch appeared because the active flight plan had not been updated after a reroute.