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J/37 Optimum boat speed for true wind speed
True Wind Speed Point of Sail Angle Off True Wind Target Boat Speed (knots) Apparent Wind Speed Apparent Wind Angle
6 kts Optimum Beat 45° 5.15 10.10 24°
  60° 60° 6.11 10.30 29°
  90° 90° 6.42 8.65 42°
  120° 120° 4.75 5.36 70°
  Optimum Run - Spinnaker 140° 4.75 3.82 88°
  Optimum Run - Jib 169° 2.95 2.68 158°
  Optimum Run - Jib with pole 172° 3.19 3.82 164°
           
8 kts Optimum Beat 43° 5.92 12.63 24°
  60° 60° 6.90 12.54 31°
  90° 90° 7.17 10.52 47°
  120° 120° 5.85 6.99 74°
  Optimum Run - Spinnaker 143° 5.80 4.80 97°
  Optimum Run - Jib 169° 3.92 3.98 158°
  Optimum Run - Jib with pole 173° 4.23 3.60 164°
           
10 kts Optimum Beat 40° 6.25 14.82 24°
  60° 60° 7.24 14.33 32°
  90° 90° 7.60 12.18 52°
  120° 120° 6.60 8.56 74°
  Optimum Run - Spinnaker 150° 6.36 5.50 114°
  Optimum Run - Jib 169° 4.83 5.02 159°
  Optimum Run - Jib with pole 172° 5.21 4.57 164°
           
12 kts Optimum Beat 39° 6.44 16.84 24°
  60° 60° 7.43 16.06 35°
  90° 90° 7.91 13.74 55°
  120° 120° 7.06 10.13 83°
  Optimum Run - Spinnaker 163° 6.53 6.01 144°
  Optimum Run - Jib 170° 5.68 6.12 160°
  Optimum Run - Jib with pole 172° 6.12 5.62 165°
           
14 kts Optimum Beat 38° 6.54 18.87 25°
  60° 60° 7.55 17.74 37°
  90° 90° 8.17 15.18 57°
  120° 120° 7.40 11.74 87°
  Optimum Run - Spinnaker 169° 7.00 7.17 158°
  Optimum Run - Jib 170° 6.42 7.30 162°
  Optimum Run - Jib with pole 173° 6.84 6.83 166°
           
16 kts Optimum Beat 38° 6.60 20.65 25°
  60° 60° 7.63 19.35 38°
  90° 90° 8.36 16.44 59°
  120° 120° 7.70 13.38 90°
  Optimum Run - Spinnaker 172° 7.43 8.60 165°
  Optimum Run - Jib 172° 6.96 8.64 166°
  Optimum Run - Jib with pole 172° 7.35 8.25 167°
           
20 kts Optimum Beat 38° 6.67 24.15 26°
  60° 60° 7.74 22.50 41°
  90° 90° 8.58 19.01 63°
  120° 120° 8.23 16.63 95°
  Optimum Run - Spinnaker 173° 8.22 11.75 169°
  Optimum Run - Jib 173° 7.74 11.72 169°
  Optimum Run - Jib with pole 173° 8.17 11.37 168°
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