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A DME may be co-located with VOR. Such a VOR/DME will be coded as a Navaid.type equal-to 'VOR_DME', with two correspondning corresponding NavaidEquipment instances, a VOR and a DME.
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the NavaidComponent.providesNavigableLocation for the VOR will be equal-to 'YES' and the NavaidComponent.providesNavigableLocation for the DME will be equal-to 'NO'.
The VOR provides the bearing information, whereas the DME is used for the distance information.
NDB collocated with DME
A DME may be co-located with a NDB. Such a VOR/DME will be coded as a Navaid.type equal-to 'NDB_DME', with two corresponding NavaidEquipment instances, a NDB and a DME.
For both NavaidEquipment the NavaidComponent.collocationGroup will be equal-to '1'.
If the NDB is the navigable location of the navaid when the navaid is used as significant point:
the NavaidComponent.providesNavigableLocation for the NDB will be equal-to 'YES' and the NavaidComponent.providesNavigableLocation for the DME will be equal-to 'NO'.
The NDB provides the bearing information, whereas the DME is used for the distance information.
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