Prevailing Visibility

[FMM910]

What is the general concensus on the new method of calculating Visibilties?

There is a difference between civil & military methods and colour states. Is this a hazard to flight safety?

I have to admit, I am finding it difficult to 'get my head round it!', especially in the training & supervision environment.

Discuss; I might learn something!

[ProfessionalStudent]

I could see a problem if you decide to use a civvy field as a div where the prevailing vis is green, but in fact the worst vis is actually yellow (as the worst vis does not meet the criteria to be added as a directional worsening).... Military fields, I believe, will give a directional vis if it means a change in colour state, whereas civvy fields do not use colour states (MOMIDS purely interprets the parameters and adds the pretty colours for us aircrew). Shouldn't affect the price of fish that much though as the approach should still be in limits.

At least it's nothing to do with generally increasing the reported vis and thus allowing commercial jets to take off in punker (more punk?)conditions and thus earn more revenue... Oh no, wait a minute...:E

[PPRuNeUser0211]

We just took the easy option and halved (i think?) any vis that a civvy airfield gave in a taf/metar unless they specifically reported something else. Think that's the criteria for prevailing vs specific vis? If prevailing vis is no more than double the vis in any direction its all that's reported unless blah blah blah some rule about low vis, can't remember exactly at the moment.

In short, believe nothing a met man tells you!

[BEagle]

Conversion between RVR and Met reported visibility varies between Military and Civil JAR-OPS methods.

Cloud bases used in Colour states are 3/8 or more; the civil world uses 5/8 or more for cloud base reports.

Wind gust information used in military TAFs differs from that used in civil TAFs.

Just some of the differences between UK Mil and Rest of The World ways of doing things.....:ugh:

[teeteringhead]

Just you wait until we get an MAA (Military Aviation Authority) that is "new best mates" with the CAA ......:rolleyes: