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Old 24th Nov 2009, 08:57
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DRIFT...

hi...
is there a formula to calculate max drift given wind direction/speed and track??

thNks
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Old 24th Nov 2009, 09:32
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Maybe this:

when wind direction is perpendicular to your track, then

DriftAngle = 60 * WindVelocity / TrueAirSpeed
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Old 24th Nov 2009, 20:03
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I don't understand the max.

For practical purposes, a crosswind will require a wind correction angle of the CW in knots divided by the TAS in NM/min. For instance, 15 kt at 180 KTAS gives a 5º WCA. Check as many examples you want and check with the computer, it is very precise!
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Old 24th Nov 2009, 20:37
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air cowboy - as MB says, I think you have your terminology a little confused?

poldeck has given you the MAX drift which always occurs at 90 degrees off ie ALL ACROSS

For less than 90, use the 'analogue watch factor' for simplicity. Treat minutes around the face as angles off, so 15 degrees off is 15 minutes which is a quarter of the face AND a quarter of the MAX drift. 30 off is half and so on. It will work perfectly for all the flying you do. Yes, I know it does not work past 60 degrees off, but who cares? Then you use the 'poldeck value' and you will not go wrong.

Now, if you have a digital watch.........................................
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Old 24th Nov 2009, 23:37
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Now, if you have a digital watch.........................................
Too young to understand.
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Old 25th Nov 2009, 08:34
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X-wind

The mach number X WCA = x-wind component.

i.e: Mach 0.80, WCA 12 degr. X-wind component 8 x 12 = 96 kts.

happy landings
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