Plain English Meaning

A curved part of a flight route that wraps around a navigation station at a set distance, smoothly connecting two straight legs of the route.

Full Definition

A curved segment of an instrument flight route that follows a fixed-radius arc around a navigation aid (typically a VOR or DME station), used to transition between two straight route segments while maintaining a constant distance from the station. The arc is flown by referencing DME distance to keep the aircraft on the prescribed radius.

Context Anchor

Seen in instrument procedure and route-design discussions when a published path curves smoothly into another segment.

Derivation

From Latin tangere, meaning 'to touch.' A line touches a at one without crossing it. A tangential arc is the curved portion between two such touching lines — the route 'touches' the arc at each end and follows the curve between them.