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During my KIAD-EDDF preflight last night, I noticed some bad wind data in my mission briefing. The enroute winds at FL330 were typically 270/100 until just off the coast where your pseudostations were reporting winds 180/17 for several hundred miles then returned to normal. I've noticed this during an earlier flight, and it created problems for the PMDG 744X so I looked a little closer at the wind data before starting this trip.I've got route enhancement and virtual stations turned off in the settings.I looked for an easy way to delete those offending locations, then thought about modifying the weather enroute but couldn't find an easy way to do that either, other than turning off winds aloft.I have just loaded the same flightplan for comparison (it's been 20 hrs), and find winds are consistent until 5040N (N50.0 W040.0) where they shift from 295/106 (for the past 400 nm) to 349/35, then shift to 208/131, then to 300/96 as the route reaches the continent.The current North Polar Stereographic


Dan Downs KCRP

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Hi Dan,There is nothing fake about ASX wind data. It comes from up-to-date world forecast system data at 1x1 latitude/longitude resolution. Most likely you are comparing older forecast graphics to newer ones that ASX is using. While ASv6 used to make it a point to use older data so it matched aviation reports, with ASX we are using as real-time as we can get. Sometimes this means the reports will differ. But you can always use ASX mapping and reporting to get the real picture.A note about the stations, this could be part of the reason you get unpredictable results in sparse areas... Without the dynamic stations turned on you are getting lower resolution and things may be bundled up from reports from further away than you are expecting.Anyhow, with SP2 we are using data smoothing as well as other depiction tricks to reduce wind shifts. So even those 40 degree changes in stations/data you are seeing will be smoothed and more consistent.FWIW it is not and has never been AS that is creating instantaneous wind shifts. There are literally hundreds of threads about this.Best,


Damian Clark
HiFi  Simulation Technologies

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Just to clarify about wind shift issues... when any external weather add-on sets weather to FSX, interpolation errors, layering issues, and many more additional depiction problems occur. Before SP2, we could lock ALL data across the globe at 10nm intervals to have exactly the same wind data and you would still receive 90-180degree wind shifts somewhat consistently depending on the area you were flying. My point being that the problem is not the data even though depending on options you may be getting various data variations over oceanic reporting stations.Best,


Damian Clark
HiFi  Simulation Technologies

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Thanks for the feedback. I am eagerly looking forward to your service pack, and a better understanding of your implementation strategy helps in the use of the product.The whole arena of oceanic weather is a puzzle to me. I fly a C-414 between KCRP-KDAL often, the winds aloft for flight planning on obtained from forecasts. The only actual winds are those provided twice a day by radiosonde (weather ballons) or PIREPS.. I didn't realize that actual data for winds aloft is available by any other means, and I'm really puzzled how data is acquired in the oceanic regions.Regardless, your ability to manipulate the data through programmatic algorithms to achieve the desired smoothing seems to be a good strategy. As anyone with flight experience can attest, even surface altimeter settings can be reported +/- 0.03 inHg from different AWOS stations within the same area, yet the real pressure gradiants are not like this. The difference between simulation and real world is in real world the aircraft is subject to actual conditions but in the simulation the data and it's errors have effect.Still wonder about oceanic data... real or forecast, and if real how is that obtained?


Dan Downs KCRP

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Hi Dan,We can't say too much especially in light of recent events, but here's what I can say: The winds data for ASX is technically a forecast but is based on radiosonde and PIREPS (real data, but unfortunately old before it ever makes it to distribution). I guess the same could be said about any forecast. The big difference however is that we are updating every 2 hours for the nearest forecast to "now". If you were able to get winds charts updated that often they would certainly match. In fact, I can tell by the imagery you provided that the upline data used to generate the forecast imagery is the SAME as used by ASX with perhaps some small differences in the way the data is synthesized :)I think the biggest factor in you getting different winds data compared to graphics is your disabling of virtual stations. With SP2 you should be able to turn that back on (along with the wind smoothing) to get the best of both worlds.. better resolution/ coverage, and minimal shifts.This also highlights the need for expansion of forecast data viewing capability within AS (something for a future version), to make it very easy to sync up AS data used with any "real" weather reports/graphics you are comparing to.Best,


Damian Clark
HiFi  Simulation Technologies

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Well then SP2 will be added to my system as soon as it's available.My preference is for realistic weather, only to the extent that it seems real during the simulation. If the simulation varies somewhat from actual or interpolated weather to ensure the perception of reality (ie, wind shift take time and distance to occur) then I can't see that as a problem.Thanks for the explanations.


Dan Downs KCRP

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