WindsAloft.dll version 1.0

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Hi all,I've uploaded WindsAloft.DLL version 1.0 for you guys to play with. I've also included the source for it so that you can tweak it if get some sick and twisted masochistic yearning. :-) A note about the functions ran1() and gasdev(). These are numerical functions that permit me to calculate a normal gaussian distribution. I use this distribution to create a wind change pattern that favors the current direction but can change fully 180 degrees. I would suggest that you not fiddle with those methods since they are rather highly optimized. If you care to know about these functions you can find them in Press, Teukolsky, Vetterling, & Flannery's Numerical Recipes, Second Edition. Happy wind change! Cheers, Tony

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> These are numerical functions that permit me to calculate a normal gaussian distribution.Woohoo! Now you're talking my language. :)- David Sandberg[br][br]

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Winds aloft are the winds coming from a magnetic diretion,as in your heading of the aircraft is 330. The winds aloft are reported by the flight service station as360 degrees magnetic, That means you have a right crosswind from the nose of the aircraft by 30 degrees to the right Jeff Akins

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Winds aloft means winds encountered when flying at altitude, rather than near or on the ground. For example, the winds you encounter when flying at 10K feet will often be very, very different from those at ground level, and can dramatically affect both your course and speed (over the ground, that is ... TAS remains the same). As such, knowing what the winds aloft are expected to be and accounting for that in your flight planning is critical.If you don't do anything special in Fly!, the winds will always be the same as at the surface, no matter what your altitude is. By explicitly setting Winds Aloft (whether via inputting real world data by hand, or using this new DLL for random winds), they become an issue that you as a sim-pilot must deal with. (Of course, I suppose Tony's random Winds Aloft DLL introduces these winds in a way that can't really be accounted for during preflight ... although I haven't looked at the DLL yet myself, so maybe Tony has added some sort of reporting feature to it?)- David Sandberg

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Many thanks, Tony! Will have to grab and check it out once I get home from work (on a break at moment).Ken WoodMeteorologistCNN International Weather :-sun1

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Hi David,No. No reporting feature...yet. :-)I suppose that I could whip up something that could report the weather in "official" format. I'll think about it over the weekend, but as I'm going to be out and about, I won't get to it until sometime next week.Cheers, Tony

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Winds aloft forecasts and METAR use TRUE direction, not magnetic direction for winds. ATIS, ASOS, and AWOS report wind direction as magnetic rounded to the nearest 10 degrees.To compute the magnetic direction, you have to consult your sectional, locate the isogonic line that crosses or is nearest your course line, and then add or subtract the magnetic variation from a true direction to get the magnetic direction.If the magnetic variation is East, you subtract it from the true direction. If the varition is West, you add it to the true direction.In some areas, the magnetic variation is only a few degrees. In my neighborhood, the variation is considerable - about 16 degrees East.John

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