Originally Posted by
IO540
The old CAA CPL (or the old CAA ATPL for that matter) gives you an honorary IMC Rating, which needs 1800m min vis for any VMC.
What better way to spend your day, sat in front of a computer with a gale howling around you

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I don't know about the new JAA licencing, but VMC in controlled airspace, where allowed,(B,C,D,E) requires a minimum flight vis of 5km. A Pilots licencing requirements may increase this, but they certainly cannot reduce it. Therefore a vis of less than 5km in these airspaces = IMC, and IFR or SVFR clearances are required.
A pilot can ask for a SVFR clearance at any time, but the minima, even for an ATPL/IR are, I believe, 1800m vis/600' cloudbase.
Having said that, should you ask for SVFR on a gin clear CAVOK day, you may get a very short reply

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The crazy thing, at least in the UK, is that a plain PPL can fly VFR in most class D airspace with a flight vis of at least 5km. But for SVFR in the same airspace a minimum vis of 10km is required

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