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The second case shows a Navaid of type ILS which is composed of five navaid equipment features. A Localizer, a Glidepath, a NDB (locator collocated with the outer marker) and two MarkerBeacons, one of it an outer marker and the other one a middle marker.
Now for All these navaid equipments may also be used for other purposes than being part of the ILS.
For example, the NDB may also be used as SegmentPoint for a terminal procedure. In this case the NDB has to be available as SignificantPoint. Hence, the NDB has to be encoded as separate Navaid feature referencing as navaid equipment the NDB feature.
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