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Old June 10th 05, 07:11 PM
City Dweller
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I wrote the wind correction routine once in C, great excercise in high-school math. Here it is in case you need it.




float fWindAngle, fWindSpeed, fTrueCourse, fTrueHeading, fTrueAirspeed;

// Sample data
fWindAngle = 355;
fWindSpeed = 10;
fTrueCourse = 5;
fTrueAirspeed = 100;

float pi = 3.1415926f;

float fGamma = 180 + fTrueCourse - fWindAngle;
while( fGamma = 360 )
fGamma -= 360;

// Use theorem of sines
float fSinCorrection = sin( fGamma / 360 * 2 * pi ) * fWindSpeed / fTrueAirspeed; // sin of angle

float fCorrAngle = 360 * asin( fSinCorrection ) / 2 / pi; // angle in degrees

float fCosCorrection = cos( ( 180 - fGamma - fCorrAngle ) / 360 * 2 * pi ); // cos of angle opposite to GS

fTrueHeading = fTrueCourse + fCorrAngle;
if( fTrueHeading 360 )
fTrueHeading -= 360;

if( fTrueHeading 0 )
fTrueHeading += 360;

// Use theorem of cosines
float fGroundSpeed = sqrt( fTrueAirspeed * fTrueAirspeed + fWindSpeed * fWindSpeed - 2 * fTrueAirspeed * fWindSpeed * fCosCorrection );



"Chris W" wrote in message news:Erjqe.25852$rb6.24822@lakeread07...
I was wondering if anyone had an E6-B flight computer program for the HP
15C calculator. I'm mostly interested in the back side of the E6-B with
course correction for winds. Density altitude, and True airspeed
calculations would also be nice. I could always write the program
myself, but I'm feeling a bit lazy

--
Chris W

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