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Hood
Mar-20-2014, 10:42
A lovely little explanation is here:

http://www.tangmerepilots.co.uk/NewForum/viewtopic.php?f=65&t=14834

Hood

9./JG52 Ziegler
Mar-20-2014, 10:46
:thumbsup: lol, Excellent!

No601_Swallow
Mar-20-2014, 12:03
Thanks Hood.

Which reminds me of one of the late and great Tommy Cooper's: "And the back of his anorak was leaping up and down, and people were chucking money to him. I said 'Do you earn a living doing that?' He said 'Yes, this is my livelihood.''

Talking of wind direction, I've been having a look at how the FMB records wind direction in the [GlobalWind] section of the .mis file. Yet another layer of weird, and I'm wondering if anyone (who, you know, understands maths and tangents and things) has an explanation.

Here's a wee table of numbers, for eight wind directions:



FMB Wind Angle
[GlobalWind] numbers


0
Power 3.000 0.000 0.000


180
Power -3.000 0.000 0.000


90
Power 0.000 3.000 0.000


-90
Power 0.000 -3.000 0.000


45
Power 2.121 2.121 0.000


-135
Power -2.121 -2.121 0.000


-45
Power 2.121 -2.121 0.000


135
Power -2.121 2.121 0.000


And finally a real angle!



-161
Power -2.837 -0.977 0.000



Any interesting info would be appreciated. Is it to do with circles and quadrants and tangents and things? And what about the last number of the three. It seems to be always a zero...?

Edit: Do these numbers in the .mis file somehow combine windspeed and angle? Vectors? Is that a thing? Does the FMB split the windspeed into components? In which case, would the third number have been intended for updrafts and thermals and such?

Is this one of those moments when you want to find a cat to kick, because this game was so so close to absolute genius, and yet...?

SoW Reddog
Mar-20-2014, 12:39
uMet and vMet.

No601_Swallow
Mar-20-2014, 14:23
OK. Salmo references this document: https://www.eol.ucar.edu/content/wind-direction-quick-reference in his random weather script.

But my brain's gone on strike. It wants better pay and conditions. i.e. a beer.