IFR Enroute & Approach Chart Symbols

On enroute charts, an airport that has a published instrument approach procedure is shown in green or blue. The color signals it is part of the IFR system, not the towered/non-towered VFR coloring.

An airport with no instrument approach (VFR only) is printed in brown on the enroute chart.

The text by an enroute airport gives the name, the identifier, the field elevation in feet MSL, and the length of the longest runway in hundreds of feet.

Military airfields are charted with the operating service abbreviation (AFB, NAS, AAF, MCAS). Access is restricted, and you should expect military traffic in the vicinity.

A part-time tower or approach control may be noted by its hours of operation; outside those hours the airspace and frequencies change, so check the times.

Water landing areas (an anchor symbol) and heliports (a circled "H") are charted on enroute charts the same way as on VFR charts when they are part of the IFR system.

The same hexagon family used VFR: a plain hexagon (VOR), a hexagon in a notched rectangle (VOR-DME), or a hexagon with three filled tabs (VORTAC). These anchor the low-altitude airway system.

A box names the station, its frequency, its three-letter identifier, and the Morse code. Channel numbers are also shown for TACAN/DME.

A NAVAID box drawn with a drop shadow indicates the station also has an associated Flight Service Station that provides communications.

A circle of dots marks a Non-Directional Beacon used for ADF navigation and as a fix or compass locator.

An underlined frequency means voice is not available on that NAVAID frequency.

A TACAN provides bearing and distance to military aircraft and DME to civil pilots. The box lists the TACAN channel alongside the paired VOR frequency for VORTAC stations.

A Non-Directional Beacon co-located with DME, providing ADF bearing plus slant-range distance, and often serving as a fix or approach aid.

A low-power NDB co-located with an ILS outer (LOM) or middle (LMM) marker; it is used during the approach and can define a fix.

LF/MF beacons (including marine radiobeacons usable with an ADF) are charted with a dot pattern similar to an NDB.

A class letter — (T) terminal, (L) low altitude, or (H) high altitude — indicates the NAVAID's standard service volume, which sets the altitudes and distances over which its signal is guaranteed usable.

The dot-dash code in the NAVAID box is the station's Morse identifier; listen and verify it before navigating off the station.

A Victor airway, labeled "V" plus a number, is a VOR-based low-altitude route flown from 1,200 ft AGL up to (but not including) 18,000 ft MSL.

On high-altitude charts, jet routes are labeled "J" plus a number (e.g., J80) and are flown in Class A airspace from 18,000 ft MSL up to FL450.

GPS/RNAV routes are labeled "T" for low altitude and "Q" for high altitude. They are drawn in blue to distinguish them from the conventional VOR airways.

The MEA, printed along the airway, is the lowest altitude that guarantees both obstacle clearance and acceptable NAVAID signal reception over the whole segment.

An altitude followed by an asterisk (*) is the MOCA — it guarantees obstacle clearance for the whole segment but assures NAVAID reception only within 22 NM of the station.

An altitude preceded by "MAA" is the highest altitude you may use on that segment, usually to prevent two stations on the same frequency from interfering.

The MRA, flagged with an "R" in a flag symbol, is the lowest altitude at which an intersection can be reliably identified from the off-route NAVAID.

An "x" flag with an altitude and direction marks a fix that must be crossed at or above a stated altitude when continuing on the airway toward higher terrain.

The number printed along a route is the distance in nautical miles between the fixes or NAVAIDs that bound that segment.

A number inside a small box/oval along the airway gives the total mileage between the two NAVAIDs, in addition to the shorter segment distances.

A bracket-style symbol with two mileages tells you where to switch from navigating off the NAVAID behind you to the one ahead, when it is not simply the midpoint.

The bold number with an arrow along an airway is the magnetic course to fly, defined by the outbound radial of the NAVAID behind you.

The OROCA printed in each grid quadrangle provides obstacle clearance — 1,000 ft in non-mountainous areas, 2,000 ft over mountains — but it does not guarantee NAVAID reception or communications coverage.

A second MEA flagged with "G" (or "GNSS") is the minimum enroute altitude when navigating by GPS/RNAV instead of ground NAVAIDs; it is frequently lower than the conventional MEA.

An "MEA GAP" annotation marks a stretch where NAVAID signal coverage at the MEA is not assured, so you may briefly lose positive course guidance.

Some airways are authorized in only one direction; an arrow or note shows the permitted direction of flight along that segment.

When a segment has a different MEA for each direction of flight, both values are printed, each tied to its direction arrow.

A note may flag a radial as unusable beyond a certain distance or below a certain altitude because of terrain shadowing or signal interference.

Preferred routes (listed in the Chart Supplement rather than always drawn) are the routings ATC expects between busy airport pairs to keep traffic flowing smoothly.

A solid triangle marks a reporting point/intersection defined by the crossing of two or more NAVAID radials or bearings. Its five-letter name is printed beside it.

A four-pointed star marks a GPS/RNAV waypoint identified by latitude/longitude rather than by a ground NAVAID.

A small "x" on the route marks a computer-navigation fix or a point used only to break the segment mileage — not a required reporting point.

A fix labeled with a distance (e.g., "15 DME") is defined by a specific DME range from a NAVAID along the route.

A solid (filled) triangle is a compulsory reporting point where a position report is required without radar; an open (unfilled) triangle is reported only when ATC requests it.

A plain four-point star is a fly-by waypoint (begin the turn before reaching it to roll out on course), while a star inside a circle is a fly-over waypoint that must be crossed before turning.

A five-character Navigation Reference System waypoint (a letter, the ARTCC region letter, and digits) provides a grid of RNAV fixes used for flexible routing and reroutes.

An open (unfilled) reporting-point triangle, or a "RADAR" note, indicates a position report is not required there while you are in radar contact.

A fix may be defined by a NAVAID radial plus a DME distance, or by two crossing radials/bearings; the defining radials are drawn as thin lines reaching the fix.

A racetrack-shaped loop drawn at a fix shows a charted holding pattern, oriented to match the inbound course and the turn direction you should fly.

Notes attached to a holding pattern can restrict the maximum holding airspeed or specify the altitudes for which the pattern is designed.

A holding pattern drawn at an intermediate or final fix serves as the course reversal in place of a procedure turn; you fly it only as needed to get established inbound.

Holding can be defined by a DME distance or an RNAV leg length rather than timing; the chart states the leg distance to fly outbound.

A series of small "T"-shaped tick marks (a saw-tooth line) marks the boundary between Air Route Traffic Control Centers (Centers).

A box with the Center name and a serrated/shadowed edge gives the Center remote communications outlet and the frequency to use in that area.

FSS frequencies are listed above the associated NAVAID box; standard frequencies like 122.2 are assumed and may not be reprinted everywhere.

An RCO is a remote transmitter/receiver that extends Flight Service coverage; its frequency is printed near the associated FSS so you can reach the briefer from low altitude.

Terminal approach and departure control frequencies serving an airport may be tabulated; they sequence you between the enroute Center and the tower.

Some NAVAIDs continuously broadcast Hazardous Inflight Weather Advisory Service (HIWAS); an icon or note on the NAVAID box tells you the recorded weather is available there.

Special-use airspace is outlined and labeled with its designator (R-, P-, W-, A-). On enroute charts a margin tabulation gives the altitudes, times, and controlling agency.

An MOA is outlined and named on the enroute chart; IFR traffic is separated from active MOAs by ATC, but the area is charted so you know where it is.

Boundaries such as an Air Defense Identification Zone or oceanic control areas are charted with distinct line patterns and labeled along the boundary.

An NSA is charted where pilots are asked to voluntarily avoid flight; flight through it can be made temporarily mandatory by NOTAM.

TFRs are temporary and are not preprinted on the enroute chart; the legend reminds you to check NOTAMs before every flight.

On the plan view, a fix labeled "(IAF)" is where the published instrument approach begins — the transition from the enroute structure onto the procedure.

On a non-precision approach the FAF is marked by a bold Maltese cross in the profile view; it is where the final descent to the runway begins. On an ILS, the glideslope intercept point serves this role.

The Maltese-cross symbol in the profile view pinpoints the Final Approach Fix for the non-precision (localizer/VOR/NDB) version of the approach.

The MAP is where you must begin the missed approach if the runway environment is not in sight. On a non-precision approach it is defined by a fix, a DME distance, or a timed interval from the FAF; on an ILS it is the Decision Altitude.

A heavy dashed line in the profile and plan views shows the missed-approach climb path; the icon strip at the top of the plate summarizes the missed-approach steps.

A descending line in the profile view represents the electronic glideslope (ILS) or glidepath (LPV/LNAV-VNAV) along with the threshold crossing height.

A barbed (arrowhead) symbol in the plan view shows the charted procedure turn used to reverse course and get established inbound; the side and the remain-within distance are specified.

The minimums box lists the lowest altitude you may descend to: a Decision Altitude/Height (DA/DH) for precision and approach-with-vertical-guidance, or a Minimum Descent Altitude (MDA) for non-precision, along with the required visibility.

The minimums table is divided by approach category (A, B, C, D, E), which is based on the aircraft's reference landing speed; faster aircraft use higher minimums.

A separate line of minimums applies when you will circle to land on a different runway; circling values are usually higher than the straight-in minimums.

A fix in the profile view that allows a further descent once past it, provided the airplane is clear of the obstacle that set the earlier, higher altitude.

A circle (usually 25 NM, centered on a NAVAID or fix) divided into sectors gives the Minimum Safe Altitude — emergency obstacle clearance, not for normal navigation.

A small icon near the runway in the plan view shows which approach lighting system is installed (e.g., ALSF, MALSR), which can reduce the landing visibility minimum.

A long tapered (feathered) arrow in the plan view depicts the localizer course; the shaded side indicates the side of the course on which the "blue/yellow" sectors lie.

The IF marks the start of the intermediate segment, between the initial approach fix and the final approach fix, where you align with the final course and begin slowing/configuring.

A curved transition drawn at a constant DME distance from a NAVAID lets you join the final approach course by flying an arc instead of a straight feeder route or course reversal.

A feeder route connects the enroute structure to an initial approach fix, labeled with its course, distance, and minimum altitude to fly.

A "V" tick on the profile of a non-precision approach marks the VDP — the earliest point from which a normal descent to the runway can begin once you have the required visual references.

The TCH is the height in feet at which the glidepath crosses the runway threshold; it is printed near the runway in the profile view.

The TDZE is the highest elevation in the first 3,000 ft of the landing runway; minimums and the visual segment are referenced to it.

The airport elevation — the highest point of the usable runways — is printed near the airport sketch and is used as the reference for circling minimums.

The visibility required for each line of minimums is shown either as Runway Visual Range in hundreds of feet (e.g., "24" = RVR 2,400) or as statute miles/fractions.

A reference table tells you how much to raise the visibility (or which minimums to use) when certain approach lights or equipment are out of service.

The plan view is the overhead "map" portion of the plate showing the approach course, fixes, feeder routes, holding, terrain/obstacles, and the MSA circle.

The profile view is the side-on diagram showing the descent: fix altitudes, the glideslope or step-downs, the FAF, the MAP, and the missed-approach climb.

On timed non-precision approaches, a small table gives the time from the FAF to the MAP for a range of groundspeeds, so you know when to begin the missed approach.

The band across the top of the plate summarizes the essentials — approach name, primary frequency, final course, decision/missed-approach altitudes, and notes — in a standard read-down order.

The briefing strip lists the communication frequencies in the order you typically use them: ATIS, approach, tower, and ground.

A small icon by the runway encodes which approach lighting system is installed (ALSF-1/2, MALSR, SSALR, MALSF, ODALS); a filled dot in the icon means sequenced flashing "rabbit" lights are part of it.

Notations such as REIL (runway end identifier lights) and HIRL (high-intensity runway lights) describe the lighting available on the landing runway.

A symbol or note shows a visual glideslope aid — VASI or PAPI — and the side of the runway it is installed on, helping you fly a stabilized visual segment.

A note indicates the runway/approach lights are pilot-controlled by keying the CTAF a set number of times; the legend gives the click pattern for low/medium/high intensity.

For non-precision approaches a solid arrow in the plan view depicts the final approach course inbound to the runway, labeled with its magnetic bearing.

A back-course approach uses the reverse side of the localizer; expect reverse needle sensing (unless your equipment corrects it) and note there is no glideslope.

The heavy solid line in the plan view is the charted procedure track you fly; lighter lines are feeder routes, radials, or references.

"NoPT" on a route means a course reversal is not authorized (and not needed) when arriving via that transition — fly straight in unless ATC clears the procedure turn.

A "RADAR REQUIRED" note means ATC radar vectors are needed to fly the procedure because a fix or transition cannot be identified with onboard equipment alone.

A note may state that specific equipment — such as DME, ADF, or GPS — is required to fly the approach, so confirm your avionics meet it.

A snowflake icon flags an airport where cold-temperature altimeter error is significant; at or below the published temperature you must apply an altitude correction on the noted segments.

A boxed notes section carries special restrictions and procedure amendments (e.g., "Circling NA west of Rwy 18"); read it before flying the approach.

RNAV (GPS) approaches list several minimums: LPV and LNAV/VNAV give vertical guidance to a DA, while LNAV and LP are non-precision lines to an MDA. Use the lowest line your equipment and approval support.

On many RNAV approaches a large "T"-shaped depiction divides the area into arrival sectors, each labeled with a minimum altitude to descend to before reaching the associated initial fix.

Where two parallel runways are close together, a sidestep line of minimums lets you fly the approach to one runway and land on the adjacent one after being cleared.

On the airport diagram, a circled or outlined "HS" with a number marks a hot spot — a location with a history of runway-incursion or ground-confusion risk.

Spot obstacles and terrain are drawn with the same obstruction symbols and MSL heights used elsewhere, so you can see what drives the segment altitudes.

A zig-zag "lightning bolt" on the profile marks where you intercept the glideslope from level flight at the published intercept altitude.

A VCOA lets an aircraft climb in visual conditions over the airport to a specified altitude before proceeding on course, as an alternative to a low-visibility instrument departure.

A lead radial (labeled "LR") gives advance warning to start a turn — for example, onto the final course off a DME arc — so you roll out established.

The chart title names the approach by its guidance and runway (e.g., "ILS or LOC RWY 9", "RNAV (GPS) RWY 27"); a letter suffix like "VOR-A" means the approach is circling-only and not aligned with a specific runway.

A published VDA gives a recommended constant descent path on a non-precision approach. It is advisory only and does not by itself guarantee obstacle clearance below the MDA.

The missed-approach segment normally ends at a holding fix, shown by a racetrack pattern, where you hold while coordinating the next clearance.

The runway diagram on the plate shows the runway numbers, lengths, lighting, and the touchdown point, oriented as you will see them on landing.