Contessa 25

Disclaimer: The information presented on this page is intended to be used for simulation purposes only. This is an attempt at modeling a certain type of sailing watercraft, either real or imagined, based on information available from sometimes incomplete or even inaccurate sources. No claims are made as to the accuracy of this data for any purpose outside of the simulation, and your use of this data for any other purpose is solely at your own risk.

Polar plot showing boat speed over water (in knots) for various true wind speeds and angles from true wind direction
Boat wind response polar plot 		Table of values for boat speed over water (in knots, to two decimal places) for various true wind speeds and angles from true wind direction
5 kt 10 kt 15 kt 20 kt 25 kt 30 kt 35 kt
30° 0.47 0.71 0.78 0.89 0.96 0.99 1.03
40° 2.83 4.78 5.44 6.20 6.69 6.93 7.18
50° 3.36 5.50 5.98 6.71 7.20 7.48 7.76
60° 3.53 5.77 6.14 6.89 7.42 7.70 7.99
70° 3.60 5.89 6.25 7.07 7.66 7.95 8.25
80° 3.66 6.00 6.35 7.20 7.83 8.14 8.44
90° 3.69 6.09 6.43 7.29 7.92 8.23 8.54
100° 3.70 6.13 6.56 7.48 8.16 8.48 8.79
110° 3.72 6.18 6.70 7.68 8.39 8.70 9.03
120° 3.59 6.03 6.64 7.72 8.54 8.86 9.19
130° 3.38 5.72 6.47 7.56 8.37 8.70 9.03
140° 3.12 5.36 6.24 7.32 8.09 8.41 8.72
150° 2.83 4.94 5.91 6.94 7.66 7.95 8.25
160° 2.41 4.36 5.55 6.71 7.54 7.83 8.13
170° 2.17 3.97 5.29 6.47 7.30 7.58 7.86
180° 1.98 3.77 5.33 6.51 7.30 7.58 7.86


Reduction of speed through water from effect of waves (when enabled for race) for various wave heights
Wave Height Speed Reduction
0.25 m 0.1%
0.50 m 0.2%
1 m 1.0%
2 m 3.9%
3 m 8.6%
4 m 14.8%
6 m 30.2%
8 m 47.3%
12 m 76.3%
16 m 92.3%
24 m 99.7%