Introduction

This section introduces the information exchange models that are used in the context of AMD exchange.

Each information exchange model typically consists of an exchange model and an exchange schema.

The role of an exchange model typically expressed using the Universal Modelling Language (UML) is to formalize the meaning and relations of the information to be exchanged.

The role of the exchange schema is to structure the data exchange and determine a data encoding format.

The use and application of AIXM XML Schema, AMXM XML Schema, ARINC 816, and/or other GIS formats depends on implementation considerations (requirements) and actual context within the overall data chain.

On specific common data items, AMXM XML Schema data can be used as source format for AIXM 5.1 XML Schema data and reversely AIXM5.1 XML Schema data can be used as source format for AMXM XML Schema data. This requires a data transformation.

• AIXM5.1 XML Schema can be used to provide AMD, e.g. as aerodrome mapping data sets, in accordance with ICAO Annex 14/15 SARPs.
• AMXM XML can be used to provide AMDB in accordance with EUROCAE/RTCA industry standards.
• ​ARINC 816, the "Embedded Interchange Format for Airport Mapping Database", is an open encoding format aimed at, but not limited to, AMDBs which are loaded into embedded avionic systems.

The focus of this supporting material is on the encoding of AMDB features in AIXM 5.1.1. The correspondences established between the AMDB features and AIXM 5.1.1 AMD support data transformation to and from industry standards.

AIXM 5.1

The Aeronautical Information Exchange Model (AIXM) is an international exchange model for aeronautical data. It is designed to enable the management and distribution of AIM data in digital format.

AIXM 5.1 covers both Aeronautical Information Publications (AIP) and NOTAM information.

AIXM has been extended in version 5.1 to cover ED-99B/DO-272B aerodrome mapping data concepts in a manner compliant with the AIXM 5.1 design principles.

AIXM 5.1 is based on ISO19100/OGC standards.

The corresponding AIXM 5.1 XML Schema is based on GML (Geography Mark-up Language) version 3.2 and can be used in conjunction with the OpenGIS Web Feature Service 2.0 (WFS2.0) for aeronautical data exchange as SWIM information serivices.

Note that this requires WFS temporality enablement (WFS-TE) when encoding event information.

Usages of AIXM 5.1 in relation to AMD context:

• ICAO standardization context: AIXM5.1 can be used to provide AMD in accordance with ICAO Annex 14/15 SARPs.
• EUROCAE/RTCA standardization context: AIXM5.1 can be used as source AMD format for transformation into DO-272()/DO-291() AMDB.
• ARINC 816 standardization context: AIXM5.1 can be used as source AMD format for transformation into ARINC 816 data. This transformation is facilitated by first transforming AMD data into DO-272()/DO-291() AMDB. Creation of ARINC 816 data is a highly specialized task.

Reference:

http://www.aixm.aero/

Temporality model

The AIXM 5.1 temporality model sets basic requirements for features, feature events and feature states.

It explains the need for temporality in aeronautical data and provides guidelines for the creation and administration of this data.

Citing from the temporality model some important concepts to grasp:

BASELINE = a kind of time slice that describes the feature state (the set of all feature’s properties) as result of a permanent change.

PERMDELTA = a kind of time slice that describes the difference in a feature state as result of a permanent change.

TEMPDELTA = a kind of time slice that describes the overlay of a feature state during a temporary event.

SNAPSHOT = A kind of time slice that describes the state of a feature at a time instant, as result of combining the actual BASELINE time slice (valid at that time instant) with all eventual TEMPDELTA time slices that are effective at that time instant.

Reference: http://www.aixm.aero/sites/aixm.aero/files/imce/AIXM511/aixm_temporality_1.1.pdf

Feature Identification and Reference

This document sets basic requirements and standards for feature identification and reference.

Chapter 2 Feature identification (UUID) contains the requirements for feature identification and reference.

Example: 2.3 UUID version and codeSpace:

On the basis of the analysis presented in Appendix 1, the use of version 4 UUID based on random number generation, is recommended for AIXM 5.1.

Reference: http://aixm.aero/sites/aixm.aero/files/imce/AIXM51/aixm_feature_identification_and_reference-1.0.pdf

Use of Geography Markup Language (GML) for Aviation Data

AIXM 5.1 uses the OGC Geographical Markup Language (GML) version 3.2.1 for the encoding of positional and shape data of aeronautical information items, such as airspace, runway thresholds, navaids, etc. 

GML is an implementation of the ISO 19107 spatial schema, which contains an extensive list of geometries, geometric properties and operations.

Reference: TBD

Common AIXM coding guidelines

The basic data coding rules that are common to all products and services that use AIXM 5.1 as coding format.

This includes, for example, business rules that require the mandatory provision of a unit of measurement for each numerical value, rules derived from the AIXM temporality concept, data plausibility rules, coding of schedules, etc.

Example:

The gml:GeodesicString shall be used as default encoding for straight lines.

Reference:

https://ext.eurocontrol.int/aixm_confluence/display/ACG/Overview

(ICAO) Airport Mapping Data Sets

AMD specific coding guidelines are the subject of this Supporting Material.

An explicit list of business rules is not provided but these can be constructed from the common AIXM 5.1 coding guidance lines and associated business rules.

Additional business rules can be taken on board based on AIXM 5.1 business rule profiles and complemented with any of the business rules specified in ED-99() / DO-272().

It should be understood that when providing an AMDB the Industry requirements are applicable. It is however also understood that when providing an AMD set in AIXM 5.1 not all AMDB business rules do necessarily apply.

AMXM

The Aerodrome Mapping Exchange Model (AMXM) is a EUROCAE WG-44 / RTCA SC-217 data exchange specification for Aerodrome Mapping Databases (AMDB). 

The AMXM consists of the AMXM UML Model and a derived AMXM XML Schema.

The schema is a ISO/OGC GML3.2 specification for AMDB data exchange. 

It enables the sharing of AMDB data in accordance with EUROCAE / RTCA requirements. In combination with OGC Web Feature Service (WFS) it may be used to build SWIM information services.

The Aerodrome Mapping Exchange Schema (AMXM XML Schema)  is an XML Schema implementation of the DO-291C/ED-119C AMXM UML model.

The AMXM XML Schema uses a flattened feature/attribute representation that is derived from the AMXM UML Model using ISO19100/OGC standards.

The use of the AMXM UML Model facilitates the creation of a compliant custom GIS database schema. A frequently used format is shapefile (.shp). The AMXM UML Model is applicable when it is required to strictly follow ED-99D / DO-272D. 

Reference:

http://www.amxm.aero/

ARINC 816

ARINC 816 is intended to be used for applications depicting a moving map for an airport. The format builds on EUROCAE/RTCA AMDB requirements. ARINC 816 has additional data elements such as anchor points in support of map label placement and tessellated polygons.

ARINC 816 specifies the use of projected coordinates and a binary encoding. This enables a reduction of the processing steps on-board the aircraft and enables a quick and efficient use of AMDBs. 

The main objective is to support a graphical representation of an airport on a cockpit display, including elements such as the following:

• Graphical representations of airport features (e.g., runways, taxiways).
• Graphical definitions of particular zones (e.g., construction areas).
• Use of different display modes and ranges for the moving map.
• Interactions with airport map (e.g., panning).