Aeronautical charts

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An aeronautical chart is a navigational tool that provides a map of a particular geographic area, combined with information such as suggested altitude and routing information as well as navigational landmarks, and radio frequencies. Multiple charts may be used during any given flight, each with varying levels of detail. Some charts may correspond to a single specific airport, while others may represent larger regions.

The different kinds of aeronautical charts

There are many kinds of aeronautical charts. They are often separated into IFR charts, VFR charts and procedure charts.

IFR charts

IFR charts or instrument charts are used when flying by instrument/flying IFR, hence the name. They are more or less a geographically correct schematic depiction of the airports, navigation aids, fixes, the air traffic routes in between them and the airspace classification. In general the IFR charts are in a small scale (in essence the depicted features are small) and for the sake of clarity often doesn't contain more geographical features than borders, oceans and larger lakes.

The IFR charts are mainly used for route planning when flying IFR, and are often available in two or more series of charts, one with lower routes and one with higher routes. In each country's AIP (section ENR 6, En-route charts) are often small scale IFR charts.

VFR charts

VFR charts are mainly used when flying VFR, but can be used when flying IFR as well. In general they are in a larger scale than the IFR charts. In addition to the information of the IFR charts, they also contain information found on a regular topographic map such as representation of the terrain, water features, infrastructure, populated areas etc.

VFR charts are used for VFR and shorter IFR route planning and while flying VFR using pilotage and dead reckoning. They are available in many different scales and with many different symbologies, often different from country to country.

Procedure charts

Procedure charts are used when departing from an airport after take off or approaching an airport before landing. Airstrips and smaller airports only used in VFR conditions rarely have any as the traffic intensity and surrounding areas doesn't demand the use of one.

There are three very distinct types of procedure charts:

  • Approach plates which are depicting the area around the airport. They are usually for either visual approach, or several for instrument approach for each runway, each chart using different navigation aids.
  • STARs (Standard terminal arrival routes), which are describing instrument arrival routes, often several for each runway depending on the direction of arrival. Usually starting at a named fix along the route to the airport.
  • SIDs (Standard instrument departures), which are describing instrument departure routes, often several for each runway depending on the direction of departure. Usually ending at a named fix along the route from the airport.

Where to obtain aeronautical charts

Aeronautical charts are often made available freely online. Listed below are some online resources for downloading charts based on their type:

Mixed charts

VFR charts

AIP

1rightarrow.png See Aeronautical information publication for the main article about this subject.

Aeronautical information publication (AIP) is defined by the International Civil Aviation Organization (ICAO) as a publication issued by or with the authority of a state and containing aeronautical information of a lasting character essential to air navigation. AIPs normally have three parts: General (GEN), En route (ENR) and Aerodromes (AD).

The AIP contains many charts. Most of these are in the AD section where details and charts of all public aerodromes are published, sometimes charts with the air routes can be found in ENR.

A note on using old charts

While you can use old charts for navigation, in particular VFR navigation, there is in particular two things to take into account:

  • Radio frequencies and names of fixes might have changed
  • The magnetic north pole is not fixed, which will cause some problems:
    • The magnetic variation shown on the chart is probably incorrect
    • In rare cases runway numbers are changed as they are based on the magnetic heading

The current magnetic variation is calculated in FlightGear and can be found in the property /environment/magnetic-variation-deg. One way to get those for the legs of your flight plan is to take the UFO and look the property up in using the property browser in the middle of each leg. On a shorter route it may be sufficient to only take the magnetic variation in the middle of the route.

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