The figure below shows the main AIXM 5 classes used for the airspace concept.
AIXM 5.1.1 defines an airspace as follows:
A defined three dimensional region of space relevant to air traffic.
The main class in this AIXM model is the Airspace containing the basic data, such as the name and type of the airspace.
There are two main ways to describe the geometry of airspace volumes in AIXM 5:
- by providing a horizontal projection with vertical limits;
- by providing a composition rule by which the airspace is defined as a series of unions, intersections, subtractions of other airspace(s).
For the first option, the AirspaceVolume class with a related Surface will be used for the encoding.
For the second option, the airspace composition will be encoded by using the AirspaceGeometryComponent class or the AirspaceVolumeDependency class.
The class of an airspace is encoded using the AirspaceLayer object. An airspace class may be defined for the whole airspace or layers of it.
Furthermore, within an airspace a Service may be provided by a Unit using one or more RadioCommunicationChannel.
Airspaces and the service provided by the ATS unit may operate under certain schedules.
For special activity airspaces, also information about the existing type of restriction or nature of hazard, activation process and/or time of activity may be provided using the AirspaceActivation class.