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Wind
To fully understand the ltering of the wind functions it is necessary to consider the order in which WTP3
calculates the various functions and where ltering is applied.
When the wind is measured it is initially corrected for masthead unit oset and mast rotation (or twist), then the
rate-gyro corrections for pitching and rolling are applied and then the triangulation with Boat Speed is done and
Course added to get the Original Wind speed and Wind Direction.
The adjustment tables for wind shear and gradient are applied to get True Wind speed and True Wind Direction
and then these variables are ltered. From these ltered variables, the True Wind Angle is calculated and a back
triangulation is done to calculate Apparent Wind Speed and Apparent Wind Angle.
Therefore, the order of wind calculations is:
measured wind corrected wind original wind true wind apparent wind
It is the data from the last two steps of the calculation that you actually see on the displays. The various stages in
the calculation can be seen in more detail in Wind Calculation owchart.
