ICAO Annex 11
Area navigation route An ATS route established for the use of aircraft capable of employing area navigation.
ATS route A specified route designed for channeling the flow of traffic as necessary for the provision of air traffic services.
- Note 1.— The term “ATS route” is used to mean variously, airway, advisory route, controlled or uncontrolled route, arrival or departure route, etc.
- Note 2.— An ATS route is defined by route specifications which include an ATS route designator, the track to or from significant points (waypoints), distance between significant points, reporting requirements and, as determined by the appropriate ATS authority, the lowest safe altitude.
2.2.1 Selection of the letter shall be made from those listed hereunder:
- A, B, G, R for routes which form part of the regional networks of ATS routes and are not area navigation routes;
- L, M, N, P for area navigation routes which form part of the regional networks of ATS routes;
- H, J, V, W for routes which do not form part of the regional networks of ATS routes and are not area navigation routes;
- Q, T, Y, Z for area navigation routes which do not form part of the regional networks of ATS routes.
2.3 Where applicable, one supplementary letter shall be added as a prefix to the basic designator in accordance with the following:
- K to indicate a low-level route established for use primarily by helicopters;
- U to indicate that the route or portion thereof is established in the upper airspace;
- S to indicate a route established exclusively for use by supersonic aircraft during acceleration, deceleration and while in supersonic flight.
2.4 When prescribed by the appropriate ATS authority or on the basis of regional air navigation agreements, a supplementary letter may be added after the basic designator of the ATS route in question in order to indicate the type of service provided in accordance with the following:
- the letter F to indicate that on the route or portion thereof advisory service only is provided;
- the letter G to indicate that on the route or portion thereof flight information service only is provided.