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The difference between the AMD and AMDB was explained in Chapter 2. This part contains information regarding the provision and distribution of AMDB and illustrates the usage of metadata within the provision of AMD.

Obtaining and creation of AMD

Although obtaining of AMD is not the purpose of this guidance material it is important to observe that there is There is no singular and specific method that leads to successful creation of AMD. To create AMD, generally speaking two types of data are needed:

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Geographical data in essence is geospatial data (i.e. describing geographic features using geometries that can be referenced to earth locations) however not all aeronautical data is geospatial (e.g. a time schedule). Typically geographical data such as image maps are used to digitize AMD. Such geographical data, possibly following coordinate transformation, serve as geospatial reference. Using the geographical data the geospatial characteristics of AMD features within the aerodrome can then be captured in a geometry element of the resulting feature. Typical types of geometry are point, line and polygon. These notions are standardized in ISO 19107: Geographic Information - Spatial Schema. In the aeronautical information context all geospatial data shall be published in the WGS84 (EPSG 4326) Horizontal Reference System and the EGM-96 Vertical Reference System (EUROCONTROL Specification for the Origination of Aeronautical Data Volume 2: Guidance Material). 

For more information about this topic please refer to chapter Data creation

Reference Vocabulary

In this guidance the ATM Information Reference Model (AIRM) is used as the reference vocabulary for ATM information (www.airm.aero). The use of the AIRM enables the common understanding of the information to be encoded. This precedes the actual data encoding of AMD having chosen an information exchange models such as AIXM5.1 or AMXM.

Data Catalogue

The Aeronautical Data Catalogue presents the scope of the data that should be collected and maintained by an AIS organization and includes data quality requirements. For more information please refer to PANS AIM Doc 10066 Appendix 1.

Not all data required by the Data Catalogue are available in the Aeronautical Information Publication. For specific information the data originator should obtain data from other source of information, e.g. aerodrome operator.

Data update requirements

Specific requirements for how data sets should be updated are contained in ICAO Annex 15, section 6.3:

       6.3.3.1 Data sets shall be amended or reissued at such regular intervals as may be necessary to keep them up to date.

6.3.3.2 Permanent changes and temporary changes of long duration (three months or longer) made available as digital data shall be issued in the form of a complete data set or a sub-set that includes only the differences from the previously issued complete data set.

       6.3.3.3 Recommendation.— When made available as a completely re-issued data set, the differences from the previously issued complete data set should be indicated.

ICAO Doc 10066 PANS AIM Chapter 6.1 contains section Aeronautical Information Product Updates, where the provision and updates of digital data sets is described. 

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Digitizing new AMD

When no geospatial aerodrome data exists, it is necessary to digitize the aerodrome features as AMD. Digitizing new AMD possibly includes the following steps:

  • Data collection to capture necessary source material such as remote sensing images or aerial photographs used as the basis for data capturing
  • Capturing of AMD features as vector data
  • Transformation of AMD feature into target format

The capturing of AMD features requires making decisions on how to structure the data and which data coding rules to follow.

The structuring of data is in accordance with the AIXM 5.1 and the related AIXM 5.1 XML Schema based on the GML 3.2 format. When the EUROCAE ED-99D / RTCA DO-272D industry requirements need to be satisfied additional data format transformations apply based on the AMXM using GML3.2 or other GIS formats.

This guidance material does not cover the landscape of data coding rules that may apply. It is however worth mentioning in this case the OGC discussion paper on “Use of Geography Markup Language (GML) for Aviation Data”, and the industry standards EUROCAE ED-99D / RTCA DO-272D for aerodrome mapping data. Such data coding rules cover topics such as:

  • Choice of geometry type used for each AMD feature coding
  • Counter clockwise direction of encoding of vertices for outer boundaries of polygons
  • Density of points for curved features
  • Digitizing of features in one or more more geometries (e.g. splitting of Apron in several ApronElements)

Transforming existing geospatial data into AMD

When an aerodrome has geospatial data it may be transformed into a target AMD format. A typical use case is when the airport has layout drawings available in CAD files (e.g. DWG and DGN formats). It is then worth considering exploiting these files and transform their content into AMD features.

In this context it is important to note that such geospatial aerodrome data are frequently based on a local coordinate reference system. Therefore, transformation of the data into the WGS 84 coordination system is necessary.

Transformation of CAD files into AMD includes the following steps:

  • CAD file CRS inspection
  • CAD file geocoding in reference to earth location using control points and tools available in either CAD software or GIS software
  • Transformation of coordinates into WGS84 (i.e. EPSG 4326)


More information on coordinate reference systems can be found here:

https://ext.eurocontrol.int/aixm_confluence/display/public/ACG/Coordinate+Reference+System