Definition
An ARINC 424 path-and-terminator leg type that defines a straight ground track originating at a specified fix, flown along a defined course, and terminating after a specified distance has been flown along that track. The leg ends when the aircraft has travelled the published distance from the starting fix, regardless of any other navigation reference.
Plain English
A coded flight path that says: start at this fix, fly this exact heading, and stop after you've gone this many miles along that line.
Context Anchor
Seen in instrument procedure design and navigation database coding, especially in discussions of path and terminator legs used by area navigation systems.
Derivation
In ARINC 424 path-terminator coding, the first letter (F) describes the path — here, a track from a fix — and the second letter (C) describes how the leg terminates — at a specific distance. Pairing the two letters gives the full instruction: fly this path, stop at this terminator.
Why Pilots Care
It provides exact lateral and distance guidance when the procedure does not end at another fix.
Grounding Statement
Picture crossing a known point, holding a set direction, and continuing until the required distance from that point has been reached.
Intuition Check
Do not read “fix” as “repair” or “leg” as a physical part. Here, a fix is a defined navigation point, and a leg is one segment of the route.
Example Sentence 1
The departure procedure was coded as an FC leg, so the FMS flew the published track outbound from the fix and sequenced the next waypoint exactly ten miles later.
Example Sentence 2
After completing the FC leg the next instruction directed a turn toward the following fix.