Clear aircraft via routes consistent with the altitude stratum in which the operation is to be conducted by one or more of the following:
NOTE: Except for certain NAVAIDs/routes used by scheduled air carriers or authorized for specific uses in the control of IFR aircraft, Air Traffic Service (ATS) routes, and NAVAIDs established for use at specified altitudes are shown on U.S. government charts or DOD FLIP charts.
NOTE: A random impromptu routing is a direct course initiated by ATC or requested by the pilot during flight. Aircraft are cleared from their present position to a NAVAID, waypoint, fix, or airport.
NOTE: A point-to-point route segment begins and ends with a published NAVAID, waypoint, fix, or airport.
To effect transition within or between route structures, clear an aircraft by one or more of the following methods, based on NAVAIDs or RNAV:
EXCEPTION. GNSS-equipped aircraft /G, /L, /S, and /V on point-to-point routes, or transitioning between two point-to-point routes via an impromptu route.
EN ROUTE
When any part of an airway or route is unusable because of NAVAID status, clear aircraft that are not RNAV capable via one of the following alternative routes:
NOTE: Inform area navigation aircraft that will proceed to the NAVAID location of the NAVAID outage.
Include routes through Class G airspace only when requested by the pilot.
NOTE: Nothing in this paragraph must preclude a controller from issuing a routing clearance that conforms to a letter of agreement or standard operating procedure within their own facility or between facilities, is required to maintain separation or comply with traffic flow management initiatives.