TrueWind

calculate True Wind from Apparent Wind

AWA Apparent Wind Angle (relative to H) environment.wind.angleApparent
H Heading (relative to true north) navigation.headingTrue
- AWD Apparent Wind Direction (relative to true north) environment.wind.directionTrue
- AWD = MOD(H+AWA;360)

AWS Apparent Wind Speed environment.wind.speedApparent
COG Course Over Ground navigation.courseOverGroundTrue
SOG Speed Over Ground navigation.speedOverGround
- TWS True Wind Speed (relative to ground) environment.wind.speedOverGround
- TWx = SOG * Sin (COG) - AWS * Sin (AWD)
- TWy = SOG * Cos (COG) - AWS * Cos (AWD)
- TWS= SQRT (TWx*TWx + TWy*TWy)
- TWD True Wind Direction (relative to true north) ???
- TWD = ATAN ( TWx / TWy )
STW Speed Trough Water navigation.speedThroughWater
- DFT Current Drift (speed relative to ground) environment.current.drift
- DFTx = SOG * Sin (COG) - STW * Sin (H)
- DFTy = SOG * Cos (COG) - STW * Cos (H)
- DFT= SQRT (DFTx*DFTx + DFTy*DFTy)
- SET Current Set (direction relative to true north) environment.current.setTrue
- SET = ATAN ( DFTx / DFTy )

COG Course Over Ground navigation.courseOverGroundTrue
SOG Speed Over Ground navigation.speedOverGround
AWA Apparent Wind Angle (relative to H) environment.wind.angleApparent
AWS Apparent Wind Speed environment.wind.speedApparent
- AWx = AWS * Cos (AWA)
- AWy = AWS * Sin (AWA)
- TWA True Wind Angle (relative to H) environment.wind.angleTrueGround
- ATAN2(AWy, -SOG + AWx)
- TWS True Wind Speed (relative to ground) environment.wind.speedOverGround
- SQRT (POWER(AWy,2) POWER(-SOG + AWx,2))