5.156A in the Radio Frequency Table Allocation of Ireland.

Content Type
ITU FOOTNOTE
Title
5.156A
Description
The use of the band 23 200-23 350 kHz by the fixed service is limited to provision of services related to aircraft flight safety.
Source
https://search.itu.int/history/HistoryDigitalCollectionDocLibrary/1.43.48.en.101.pdf