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See topic Facility coverage.
Navaid Collocation
A NBD instance may be collocated with a MarkerBeacon.
A NDB (and marker) may only maintain a single collocation relationship at a time, which means that it is not possible to collocate a NDB with two different markers.
Usually, the NBD collocated with a marker is a locator (see NDB type above), whereas the locator in conjunction with the collocated marker is used for ILS approaches.
In the AIP collocated NDB and marker navaids are sometimes referred to as LOM, LMM or LIM, depending on marker position within the ILS.
An NDB may also be co-located with a MarkerBeacon or a DME.
For details about the coding and rules see topic Landing Systems & Navaid Collocation.
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