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Windbarbs on the map are groundlevel only

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leif
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 leif
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The Windbarbs on the vpv represent the head- or tailwind component.  
On the map they have a direction, but I do not find a way to elevate them to the cruise level.  

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5c1242ce1c84de60ae1ea618ae44df33?s=80&d=retro&r=g
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Hi Leif, at the moment the windbarbs on the map represent wind at 2000ftAGL, and its indeed not possible to select a different altitude. 

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leif
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Thank you for that explanation.  This means that the Windbarbs on the map will change altitude with terrain, which is not how airplanes fly.  
I suspect this depiction will be subject to change, as it is a bit confusing.

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leif
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Concerning the cloud symbols, it is not clear how their height is calculated.  AGL, MSL, or something in between - like GAFOR uses?

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leif
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 leif
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Let me add the following observation:

clouds at my airfield are on the deck, elevation is 1100‘, but there are higher places in the vicinity.
The cloud symbols at that time show a base of 500‘ or higher.  If this is calculated from MSL, it is absolutely correct.  But I doubt this is the case.

For elevated areas, with mountains and valleys, it is a tricky question to define the reference plane, but it is worth mentioning somewhere.

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5c1242ce1c84de60ae1ea618ae44df33?s=80&d=retro&r=g
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Both windbarbs and cloudsymbology are AGL based. referenceplane is based on terraindata used by DWD in their ICON model (we do get that data as part of their datafeed, but its not the same we use for our own terrain rendering). 

Windbarbs are also as AGL, although "which is not how airplanes fly" is in essence correct, but IMHO needs a more subtle approach. It is true airliners don't follow terrain, but in general our audience of GA pilots is often limited by airspace and/or cloudbase, resulting in "more or less" our flightpaths are following terrain. 90% of our users fly within the first 4000ft AGL, and using 2000ft AGL windbarbs on the map is a fairly good representation I think. For those cases where during longer periods higher altitudes can be flown the VPV gives a clear indication wether or not its useful to consider climbing or descending to profit more from wind. 

Last but not least, EV3 showed that hardly anybody changes the default wind forecast altitude, and I couldn't design an easy non-cluttering UI interface in EV4 for that selection, so I just left it out 😉

 

 

 

 

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5c1242ce1c84de60ae1ea618ae44df33?s=80&d=retro&r=g
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BTW, I see you used a screenprint from EasyVFR 3, what wasn't explaining correctly. We changed it now and created a dedicated weather section in our EasyVFR 4 knowledgebase at https://support.easyvfr4.aero/help/weather-easyvfr-4-app  

 

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