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In addition, also related to Navaid class are the servedAirport if any, and the availability of the Navaid defined by one or more Timesheet (see Common coding patterns for details).
A Navaid may be used a SignificantPoint, e.g. for the start or end point of a route or terminal procedure or the centre point of a TAA/MSA, etc.
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Only the VOR has also a zeroBearingDirection, a code indicating the direction of the 'zero bearing' provided by the station. For example: magnetic north, true north.
The Navaid class is also used to code landing systems (e.g. ILS, Localizer only, MLS). It will be comopsed of the corresponding instances of NavaidEquipment, e.g. Localizer, Glidepath, MarkerBeacon, DME, etc.). Finally, the Navaid and not its individual components isInstalledAt a RunwayDirection.
A NavaidEquipment isUnderResponsibilityOf an OrganisationAuthority.
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