[Lot 5] [AIXM-550] Airspace class on route segment

Description

The AirspaceLayerClass complex property is added to the RouteSegment feature.

Rationale for change

See https://aixmccb.atlassian.net/browse/AIXM-183

Route tables in the AIP and the AIP Data Set (refer to ICAO Doc 10066, App 2 ENR 3.1/2/4 item 3 and ENR 3.3 item 4 and ICAO Data Catalogue #AIP-DS#) should indicate the airspace classification along with upper/lower limits of the route segment. AIXM 5.1.1 does not offer the possibility to encode the airspace class of a route segment.

The Airspace contains a property (AirspaceLayerClass) and there exists an  association Airspace -> Route (protectedRoute). However, this association combined with a definition of a dedicated Airspace (e.g. type = AWY) is not sufficient because the class of airspace can differ from route segment to segment.

Impact assessment

There is no impact on existing implementations as the current AIXM 5.1(.1) data remains fully valid against AIXM 5.2.

When receiving data from AIXM 5.2 systems that use the new AirspaceLayeClass object, AIXM 5.1.1 implementations may apply the backward mapping rules described in this document.

Mapping AIXM 5.1.1 to AIXM 5.2 (forward)

Not applicable

Mapping AIXM 5.2 to AIXM 5.1.1 (backward)

The following backwards mapping algorithm is proposed:

[MAPC-03] For each RouteSegment that has airspaceClass child elements:

From the three backward mapping options discussed for this mapping case, the first two (discard the value or use an extension) are straightforward and do not need any further details. The 3rd option (backward mapping into a Note) is detailed in order to provide a complete description of this case and its conversion option. The following mapping into Note algorithm is proposed:

• Remove the elements airspaceClass elements
• Add an annotation.Note associated with the RouteSegment class having:
• purpose=“OTHER:BACKWARD_MAPPING”;
• LinguisticNote.note=”airspaceClass[1].AirspaceLayerClass.classification:<value of classification>, <levels>, <timesheets>, etc. ”, where
  • “[1]” indicates that this needs to be repeated as many times as necessary to cover all occurrences of the airspaceClass.AirspaceLayerClass
  • <levels> should be extracted from the child associatedLevel.AirspaceLayer elements, if they exists, applying the general [MAPC-03] translation into note algorithm;
  • <timesheets> should be extracted from the child timeInterval.Timesheet elements, if they exists, applying the general [MAPC-03] translation into text algorithm.

Mapping example

(Note: for mapping test data see: https://github.com/aixm/mapping_52_511/tree/master/AIXM-xxx) 

AIXM 5.2	AIXM 5.1(.1)