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The corresponding data type contains a uom attribute. For a VOR NDB only the value equal-to 'KHZ' shall be used.
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For NDB PANS-AIM Appendx 1 requires the magnetic variation to be provided. For details about the encoding including rules see the topic Magnetic Variation.
Navaid Component
An NDB may be co-located with a MarkerBeacon. This will be coded as a Navaid with two correspondning NavaidEquipment instances, a VOR and a DME.
For both NavaidEquipment the NavaidComponent.collocationGroup will be equal-to '1'.
If the VOR is the navigable location of the navaid when the navaid is used as significant point:
the NavaidComponent.providesNavigableLocation for the VOR will be equal-to 'YES' and the NavaidComponent.providesNavigableLocation for the DME will be equal-to 'NO'.
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NDB Type
This information is not explicitly required by PANS-AIM. However, this information may be relevant for ARINC 424 coding.
In AIXM 5 the Navaid.type attribute may carry the value; 'ENR' for Enroute NDB, 'L' for Locator - low powered NDB used as an aid for final approach (also known as a compass locator) and 'MAR' for Marine beacon.
ARINC 424 contains 2 dedicated record types for NDB. One for NDB NAVAID (DB) containing all LF and MF NDBs and selected Marine Beacons defined in the enroute structure and one for the Terminal NDB (PN). Both record types contain the data field NAVAID Class (CLASS), that, inter alia, is used to distinguish between NDB, Locator and Marine Beacon (additional classification elements are part of this data field which do not fully coincide with AIXM 5 concept, e.g. codes for high powerd NDB , low powered NDB, etc.).
Navaid Component
An NDB may be co-located with a MarkerBeacon or a DME.
For details about the coding and rules see topic Landing Systems & Navaid Collocation.
Coding Rules for NDB
TBD
Coding Examples
Th efigure below shows an example of different types of NDBs published in ENR 4.1. of an AIP.
More examples TBD in the scope of the DONLON AIXM AIP data set.