Cat II, III etc

Quick question: Iโ€™ve never known what the difference is between the cat rating things. Could somebody be so kind as to explain them to me? Sorry to bother you guys ๐Ÿ™‚ like I see cat II ILS approaches and cat III ILS approach charts but I have no clue what the difference is. Iโ€™ve always just clicked on the first one that comes up ๐Ÿ˜‚

Hey Ryan!

CAT is basically the unit/system used to determine landing conditions, it mainly focuses on the visibility.

CAT I: fog ceiling or visibility is 200 or more feet (height)

CAT II: fog ceiling is 200ft To 100ft visibility (height)

CAT III: fog ceiling is less than 100ft visibility. (Height)

There is something called CAT IIIB but I donโ€™t use or count that.


Itโ€™s to do with the decision height limits and how they correspond to different visibilities:

That specifies them all๐Ÿ‘†


Ahh makes sense now!! Thanks you so much ๐Ÿ™

I made this cause of your AC A321 #screenshots-and-videos @AlphaSeven ๐Ÿ˜‚


Hahaha happy to help!

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Adding on @AlphaSeven if used as the ILS category, the CAT hereby determines the minimum visibility/ceiling allowed to continue the approach.

I believe itโ€™s granted if the landing can be done with 0 visibility by the aid of the ILS CATIIIB system.


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