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Correspondingly, the data type class for NavaidComponent.markerPosition attribute allows the following values to be coded 'OUTER', 'MIDDLE,' 'INNER' and 'BACKCOURSE'.
See also topic Navaid Component & Navaid Colocation.
Altough not required by PANS-AIM, this information is published in the AIP for ILS/Localizer systems. Also the ARINC 424 record type "Airport and Heliport Localizer Marker" contains a data field "Marker Type" (MKR TYPE) for the corresponding information.
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