Definition
A flight path flown parallel to a published airway or route, displaced laterally by a specified distance to the left or right, used in RNAV operations to provide lateral separation between aircraft on the same route or to manage traffic flow.
Plain English
A route flown alongside the official one, set a fixed number of miles to the left or right, instead of directly on top of it.
Context Anchor
Seen in route planning, air traffic control instructions, and RNAV or FMS operations when aircraft are kept laterally separated from the main route line.
Derivation
Parallel' comes from Greek parallelos, meaning 'beside one another.' 'Offset' means shifted from a reference position. Together they describe a track that runs alongside the original route at a set sideways distance.
Why Pilots Care
Allows safe separation from traffic, weather, or restricted airspace while staying close to the intended route, saving time and fuel compared to a large deviation.
Intuition Check
Do not read parallel offset as just being near the route. It means a defined path a specified distance to one side of the route.
Example Sentence 1
ATC instructed the crew to fly a two-mile parallel offset route to the right of V23 until further advised.
Example Sentence 2
The crew programmed a parallel offset route into the FMS to bypass a line of thunderstorms along the airway.