Cloud distance and mist layers

[Zonkor]

The VFR rules in SERA.5001 talk about "cloud distance" for different airspaces.

How about mist layers, do these count as cloud as well?

For instance, last week in Southern England there were relatively thin (~1000 ft) mist layers that allowed for a perfectly good vertical visibility, but once you entered them the flight visibility was _greatly_ reduced.

The other thing is, flying into a cloud under VFR is an obvious no-go. But VFR pilots routinely punch through mist layers, despite encountering borderline or sub-VFR flight visibility.

Raising another question: How do you estimate flight visibility in mist layers and thickness without "having a peek" and possibly entering IMC flight visibility (and the danger of a collision)?

Michael

[Flyingmac]

If in doubt, don't fly. If already airborne, stay up there and call for help. Whatever you do. Don't risk a collision.

[Gertrude the Wombat]

"If you can see through it you can fly through it" ?

[skyhighfallguy]

The wisest pilot I have ever known was also a designated examiner for the FAA.

He gave me all my checkrides , pvt, coml single, coml multi, instrument , CFI, CFII, MEI. Had to take my ATP with someone else.

ANYWAY, I asked him the same sort of question. He asked me what the right answer was and I SAID: IF you have to ask if it is a cloud or not, IT IS A CLOUD and you have to maintain VFR cloud separation. He laughed and agreed. He even mentioned a time that he was giving a checkride and the examinee went right through a cloud 2 minutes after takeoff. He said, turn around and land and failed the guy on the spot. He violated a fundamental regulation.

So, it is a cloud and you should maintain VFR.

This assumes you are not instrument rated (USA) and not on an instrument clearance.

[Flyingmac]

In general, mist starts at the surface. We've all sat at some time waiting for it to burn off. Or at least start showing a bit of blue in the overhead. It's not cloud. On a Metar it's referred to as MIST. Vis is always in excess of 1,000 mtrs. Less than that is likely to be considered fog.


There are scenarios where the distinction between mist and cloud can be a bit blurred. Here's one example. Potentially scary for a non-instrument pilot.


File:Heavy mist.jpg - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/File:Heavy_mist.jpg)

[megan]

Less than that is likely to be considered fog.It is fog mac. Met definition (in Oz) is,

Fog: Suspension of very small water droplets in the air, reducing visibility at ground level to less than a kilometre.

Mist: Similar to fog, but visibility remains more than a kilometre.