Does anyone know how FS9 calculates winds aloft WITHOUT Active Sky? Also, I am curious to know how ASv6 winds aloft are being calculated without downloading the NOAA data (if that is even possible)? I searched the Internet up and down, but couldn't find any resources.Just to satisfy my curiosity...Thank you,Pat

Hi Pat,Not sure what MS/Jepp's aloft data source is. We use international WFS (World Forecast System/Model) data that has resolution of 1x1 lat/lon but this gets reduced when the data must get matched to the existing FS and AS pseudo weather stations (for depiction). FS by default uses its own interpolation system which is buggy and causes dramatic wind shifts and otherwise improper wind depiction. FSUIPC solves some of this, and our "DWC" direct wind control system which constantly controls the wind speed and direction fixes the rest to provide correct winds without dramatic shifts.Note that the WFS data is not the same as USA FD forecasts, but is generally the same or within 10%.FWIW the WFS data is the same thing used to plot all the real-world international winds aloft charts that are available today. We do put in some minor variation at the server level (and then again at the client level if Aloft Unpredictability/Wind Drift options are utilized) to keep things real :)Best,

Damian,that you very much for the detailed explanation. I assume the WFS consists of winds aloft calculations rather than empirical data, because otherwise there would have to be a million weather balloons dangling in the skies, correct?Thanks,Pat

Hi Pat,Yes, it's forecast data but we use the short term cycles thus its heavily weighted by actual observations (where there are observations, anyways).Best,