The 10" SkyView wind vector shows extremely high crosswinds when the wind is known to be low. For instance; at a thousand feet with ground winds in the 10-20 knot range, the wind vector would show a 67 knot crosswind. It appears this is out of the normal ranges since the GPS ground speed is more along the 10-20 knot range. Any idea why it does this and how to correct it?
SkyView Wind Vector
- Thread starter N1Flyer
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- Mar 23, 2005
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- 13,226
Your magnetic heading is off. Wind is GPS track and speed vs. Magnetic direction and true airspeed. Small errors in magnetic heading cause huge errors in wind speeds.
How much does the magnetic heading need to be out by to cause meaningful errors (i.e. more than a couple of kts) in the Wind Vector calculation? Are we talking 10 degrees off or 1 degree off?
I am just about to "swing" my dynon compass next month, so I'm keen to know how accurate the EFIS requires for accurate results.
I am just about to "swing" my dynon compass next month, so I'm keen to know how accurate the EFIS requires for accurate results.
It only takes a few degrees. If you're off by 3 degrees at 100 knots in still air, for example, you'll get a 5 knot wind indicated. 10 degrees at 150 knots would be a 26 knot crosswind. Every degree matters.
Play with http://www.csgnetwork.com/e6bcalc.html to see the effects (first to calculators combined)
Play with http://www.csgnetwork.com/e6bcalc.html to see the effects (first to calculators combined)