Forget Victor airways and jet routes, do you know about these unusual routes you'll find on enroute charts?

"Low Altitude" enroute charts are designated for flights below 18,000' MSL. "High Altitude" enroute charts are designated for flights above 18,000' MSL.

1) Victor Airways (Low Altitude)

IFR aeronautical charts depict VOR airways (airways based on VOR or VORTAC NAVAIDs) in black, identified by a "V" (Victor) followed by the route number (e.g., V12).

2) LF/MF Airways (Alaska Only + 1 In North Carolina)

LF/MF airways (airways based on LF/MF NAVAIDs) are sometimes referred to as colored airways because they are identified by color name and number (e.g., Amber One, charted as A1). Green and red airways are plotted east and west, and amber and blue airways are plotted north and south. Regardless of their color identifier, LF/MF airways are depicted in brown.

They're most commonly found in Alaska, but one still remains in the lower 48. It's called G13 and navigated off of the Manteo (MQI) NDB, located along North Carolina's coastline.

3) Jet Routes (High Altitude Victor Airways)

Jet routes are depicted in black with a "J" identifier followed by the route number (e.g., "J12") and are based on VOR or VORTAC NAVAIDs.

4) Low Altitude RNAV Routes (T-Routes)

Low altitude RNAV only routes are identified by the letter "T" prefix, followed by a three digit number (T-200 to T-500). RNAV routes are depicted in aeronautical blue, as well as the RNAV route data.

5) High Altitude RNAV Routes (Q-Routes)

RNAV "Q" Route MEAs are shown when they are above 18,000 feet. All RNAV routes and associated data is charted in aeronautical blue.

6) Helicopter RNAV Routes (TK Routes)

Two helicopter RNAV routes (TK-routes) exist in the northeast corridor between the Washington, DC, and New York City metropolitan areas. The TK-routes are for use by helicopters having IFR-approved Global Positioning System (GPS)/Global Navigation Satellite System (GNSS) equipment.

7) Joint Victor/RNAV Routes (Low Altitude)

Joint Victor/RNAV routes are depicted using black for the Victor airways and blue for the RNAV routes, and the identification boxes for each are shown adjacent to one another. Magnetic reference bearings are not shown. MEAs are stacked in pairs or in two separate columns, GNSS and Victor. On joint routes, or Victor routes, RNAV specific information is printed in blue.

8) Joint Jet/RNAV Routes (High Altitude)

When joint Jet/RNAV routes are depicted, the route identification boxes are located adjacent to each other with the route charted in black.

9) Unusable Route Segments

Unusable route segments are charter when an airway is closed or no longer in use. They're a good reminder to pilots that may have frequently used the route that it is closed.

10) Military Training Routes (MTRs)

All IR and VR MTRs are shown on enroute charts, except VRs at or below 1500' AGL. They're numbered and published in brown.

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