Last updated: 2026-04-14Contact: developer@captaincalc.com.tr
Reference basis: IMO/COLREG/STCW concepts, nautical practice, approved ship documents, and CaptainCalc calculation notes. Always verify operational decisions with official sources.
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True Wind Calculator
Convert Apparent Wind Speed & Direction plus ship's Course/Speed into True Wind Speed and Direction using vector mathematics.
Formula reference
Vector method: True Wind = Apparent Wind (vector) + Ship Velocity (vector)
AWN = −AWS×cos(AWD) | AWE = −AWS×sin(AWD)
TWN = AWN + SOG×cos(COG) | TWE = AWE + SOG×sin(COG)
TWS = √(TWN²+TWE²) | TWD = atan2(−TWE, −TWN)
AWD = direction the apparent wind is coming FROM (True bearing).
AWN = −AWS×cos(AWD) | AWE = −AWS×sin(AWD)
TWN = AWN + SOG×cos(COG) | TWE = AWE + SOG×sin(COG)
TWS = √(TWN²+TWE²) | TWD = atan2(−TWE, −TWN)
AWD = direction the apparent wind is coming FROM (True bearing).
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