Section 1. General
- This chapter prescribes general guidance for the designation of Air Traffic Service (ATS) routes.
- An ATS route is a specified route designed for channeling the flow of air traffic as necessary for the management of air traffic operations.
- This chapter applies only to those U.S. domestic ATS routes that are listed in 14 CFR section 71.13, Classification of Air Traffic Service (ATS) Routes; specifically: jet routes, VOR Federal airways, L/MF (Colored) Federal airways, and area navigation routes.
This chapter does not apply to the designation of nonregulatory oceanic ATS routes (e.g., AR11, B760, etc.) that are established primarily outside of U.S. domestic airspace. Those routes are not designated in 14 CFR part 71.
- Unless otherwise specified, the criteria and procedures for the development of ATS routes are contained in FAA Orders: 7100.41, Performance Based Navigation Implementation Process; 8260.3, United States Standard for Terminal Instrument Procedures (TERPS); 8260.19, Flight Procedures and Airspace; 8260.43, Flight Procedures Management Program; and 8260.58, United States Standard for Performance Based Navigation (PBN) Instrument Procedure Design.
ATS routes are designated as either Class A airspace (section 71.31) or Class E airspace (section 71.71) corresponding to the altitude structure of the route.
- ATS routes are designated through rulemaking action under 14 CFR part 71. The designation of ATS routes is based on air traffic and user requirements.
- ATS routes must be predicated upon NAVAIDs that are suitable for inclusion in the NAS or area navigation (RNAV) references, as applicable to the type of route.
- The benefits of the designation should outweigh any adverse effects to the NAS and provide airspace users with charted information pertaining to navigational guidance, minimum en route altitudes, changeover points, etc.
- The Rules and Regulations Group is responsible for part 71 rulemaking to establish, amend, or remove ATS routes.
- Service Center OSGs must:
- Coordinate ATS routes with appropriate offices (e.g., ATC facilities, adjacent Service Center offices, AIS, Technical Operations, and regional Frequency Management Offices) to determine if operational requirements and air traffic warrant a rulemaking action.
ATS route actions must be coordinated with and have concurrence from affected ATC facilities.
- Ensure that the FPT and the Rules and Regulations Group coordinate the details of proposed new and amended ATS routes to facilitate part 71 rulemaking action.
- Conduct periodic reviews of ATS routes in their area of responsibility in accordance with FAA Order 8260.19, Flight Procedures and Airspace, Chapter 2, and initiate Part 71 rulemaking action as necessary.
All alpha-numeric ATS route identifiers are assigned by the Rules and Regulations Group as follows:
- L/MF (Colored) Federal airways are identified by color names (Amber, Blue, Green, or Red). The identifier consists of the first letter of the color followed by a number (e.g., R-50, G-13, A-1, etc.).
- Identify L/MF (Colored) airways oriented mainly west and east as Green or Red.
- Identify L/MF (Colored) airways oriented mainly south and north as Amber or Blue.
- VOR Federal airways (below FL 180) are identified by the letter “V” prefix followed by a number (e.g., V-104).
- Jet routes (FL 180 through FL 450) are identified by the letter “J” prefix followed by a number (e.g., J-75).
- RNAV routes are identified as follows:
- Low altitude (below FL 180) RNAV routes are identified by a “T” prefix followed by a number (e.g., T-245).
- High altitude (FL 180 through FL 450) RNAV routes are identified by a “Q” prefix followed by a number (e.g., Q-120).
- Helicopter RNAV routes are identified by a “TK” prefix followed by a number (e.g., TK-502).
- ATS route numbers are assigned as follows:
- Even numbers for ATS routes oriented mainly west and east.
- Odd numbers for ATS routes oriented mainly south and north.
- Q routes: 1 through 499.
- T routes: 200 through 500.
- TK routes: 501 through 650.
- Points in route descriptions must be listed from west to east for even numbered ATS routes and south to north for odd numbered ATS routes.
- Points listed in 14 CFR part 71 route descriptions consist of:
- The beginning and end points of the route;
- Points where a route changes direction;
- Holding fixes; and
- Points required due to the maximum distance allowed between NAVAIDs (see service volume limitations in FAA Order 9840.1, U.S. National Aviation Handbook for the VOR/DME/TACAN Systems).
- When radials or bearings from a navigation aid are used to define intersections in an ATS route description, both True and Magnetic degrees must be stated in the NPRM. Only True degrees are stated in the final rule.
- The base of an ATS route must be at least 1,200 feet above the surface and at least 500 feet below the minimum en route altitude (MEA) except that route floors may be established no less than 300 feet below the MEA when:
- The 500-foot buffer would result in the loss of a cardinal altitude; or
- A definite operational advantage would exist.
- The route floor should conform, as closely as possible to the floor of transitional airspace.
Procedures for establishing MEAs are set forth in FAA Order 8260.3, United States Standard for Terminal Instrument Procedures (TERPS), and FAA Order 8260.19, Flight Procedures and Airspace. MEAs are designated in 14 CFR part 95, IFR Altitudes.
Procedural requirements may dictate designation of airspace lower than 500 feet below the MEA or Minimum Reception Altitude (MRA) in certain en route radar vectoring areas or when necessary to accommodate climb or descent operations. Such airspace must not be designated for the specific purpose of including a Minimum Obstruction Clearance Altitude (MOCA) unless use of the MOCA is procedurally required.
When action is initiated to raise the base of transition airspace associated with a route segment, care must be taken to designate, in accordance with applicable criteria, sufficient airspace to encompass IFR procedures prescribed for airports which underlie the route. Additionally, care must be taken to ensure that controlled airspace, such as transition airspace or lower floor of control area, is provided for aircraft climbing from one MEA to a higher one.