FlyWithX

IFR - IFR Charts

IFR Airways

Low Altitude (1,200 ft to FL 180):

  • V (black): Victor Airways (Low Altitude) VOR airways
  • T (blue, RNAV): Low Altitude RNAV Routes (T-Routes)

High Altitude (FL 180 through FL 450):

  • J (black): Jet Routes
  • Y (RNAV): U.S. offshore or over southern Florida.
  • Q (blue, RNAV): High Altitude RNAV Routes (Q-Routes)

More Airways

  • TK: 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.
  • Joint Victor/RNAV Routes (Low Altitude)
  • Joint Jet/RNAV Routes (High Altitude)
  • Unusable Route Segments
  • 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.

Flags

The X in a flag for a intersection, waypoint or fix regardless of if it is a NavAid means there is a Minimum Crossing Altitude. An MCA present means you must be at or above a certain altitude when passing over the fix in the direction specified.

Altitudes

Along the airway

  • MEA: the topmost number, in black.
  • GNSS MEA / RNAV MEA: the middle number, in blue, ends with a G.
  • MOCA: Minimum Obstruction Clearance Altitude, the bottom bumber, in black, with a *. Only guarantees acceptable navigation signal coverage within a limited range of a VOR station, typically around 22 nautical miles.
  • MAA: Maximum Authorized Altitude. The highest altitude. (Most of the other specified altitudes are the lowest.) With MAA- prefix on the chart.

At a fix

  • MRA: Minimum Reception Altitude (a flag with an R); the lowest altitude at which an intersection can be determined; normally above the MEA.
  • MCA: Minimum Crossing Altitude (a flag with an X); start the climb early, BEFORE the fix.
  • MTA: Minimum Turning Altitude is a charted altitude providing vertical and lateral obstruction clearance based on turn criteria over certain fixes, NAVAIDs, waypoints, and on charted route segments.

On each quadrant of the chart

  • OROCA: off-route obstruction clearance altitude (similar to the max elevation figures on the VFR sectional chart). 1,000-foot buffer in non-mountainous terrain areas, and a 2,000-foot buffer in designated mountainous areas. Doesn't guarantee signal coverage

On Approach Plates

  • MSA: Minimum Safe Altitude.

For ATC Only

  • MVA: Minimum Vectoring Altitude; the lowest that ATC is allowed to assign you heading vectors.