Originally Posted by
RAT 5
Slight drift: how many airlines have CAT 1 reversion from a CAT 2/3a ILS?
AFAIK, it's pretty much routine - or should be! I've encountered the conditions enough in my career that it was really a no-brainer after a while...
The common scenario is varying visibility, going between Cat I and Cat III. The easy solution is to brief a Cat III approach. That covers all scenarios, ending presumably with an autoland. Extend the brief to include the scenario that visibility is reported better than Cat III when on final. Include the option to continue with allowed degraded systems with the increased visibility, including a manual landing if Cat I.