Numerical values
Vertical limits
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- a "...Limit" attribute, which includes the value and its unit of measurement (as an "uom" attribute) with the list of values: UomDistanceVerticalType;
- a "...LimitReference" attribute, which indicates what reference system is used for the vertical limit value. It uses the following list of values: CodeVerticalReferenceType;
The following consistency rules between the uom value and the reference value shall be observed when encoding the data:
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Coded values (GND, UNL, etc.)
In addition to numerical values, the "...Limit" attributes can use four coded values:
in Digital NOTAM can be expressed as numerical values or as coded values (such as GND - meaning "from surface"
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As the unit of measurement attribute is mandatory in AIXM for all “...Limit” attributes, the following values are recommended when encoding the data:
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). They shall be coded as indicated in the general AIXM coding rules for Vertical Limits.