I did a flight last night from ZBAA to RKSI everything with the weather was fine until the approach. The metar was reporting visibility at the airfield was 1 mile but I was able to see the field from about 5 miles out clearly. It wasnt until I was about 2 miles out when the visibility changed and lost sight of the airport.  Is this a bug?

welcome to FSX default weather!

Oh those glorious weather updates.  You can disable updates on approach Les inside the OPUS configuration settings.  You can set it for a certain altitude and also can specify a time IIRC (can't check as I'm in the middle of a flight now) so you won't get any "surprises" as you prepare for landing.

 

As far as overall settings, I have mine set to refresh at 10min or 100km intervals.  I find the more often the weather loads, the less drastic the changes.  You'll still get clouds popping out of nowhere occasionally, but the quicker refresh is what I prefer.

 

Hope that helps some.

this is such an annoying bug in FSX!

Yes, FSX does not render vertical visibility correctly, it does not take any visibility layer below your current altitude into account so you won't see the correct ground visibility until you decend.

FSX has always assumed your current visibility, defined by the visibility layer coinciding with your altitude, extends all the way to the ground and up through the atmosphere.

 

The LWE uses the reported surface visibilities along with other meteorological parameters to set the visibility layers from the surface upwards. These layers are constructed taking into account cloud layers, inversions, etc.. The maximum upper visibility is also calculated based on overall conditions reported over the entire 800 x 800 mile weather map area.

 

Unfortunately, as we all find out, FSX simply cannot take into account any lower vis layers that are beneath your aircraft and assumes its vis extends everywhere. That's why we have options to enable Fog and Mist effects. These effects top fog and mist banks with a thin layer of stratus, simply to make them visible from above. Similar effects can be used when VV (Vertical Vis) limits are reported.

 

Please note we have posted a new Beta this morning (BST) with some improvements to the surface visibility interpolation. See our SimForums for details, also have a look at the Coming Soon topic.

 

Stephen :-)

Thanks everyone for your quick replies.

You're welcom Les. FSX has many foibles.

 

Stephen :-)