Convert between true and apparent wind speed and angle from your boat speed, and see the vectors that make up the classic sailing wind triangle.
Result
18.7kn
Apparent Wind Speed (AWS)
44°
Apparent Wind Angle (AWA) · Starboard
The apparent wind you feel on deck is the true wind plus the headwind created by your own motion, added as vectors: apparent wind = true wind + boat speed (from dead ahead). The faster you sail, the more the apparent wind swings forward and builds — which is why running downwind feels calmer than the true wind speed suggests, and why reaching in a fast boat can feel like a gale.
Approximate — assumes flat water and boat speed through the air mass equal to SOG or speed through water, whichever you enter. Not a substitute for calibrated wind instruments.
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