Bobstay Calculator
This calculator determines the tensile strength needed by the bobstay for sailboats that have bowsprits. The theory is based on the law of sines.
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Capsize Calculator
The capsize risk factor sounds rather like a formula for predicting disaster. Actually it is a formula that was used after the Fastnet Race disaster - to help guide designers and sailors.  To help understand a particular value it is best to look at the values generated by the designs of some very respected naval architects.
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Displacement Hull SpeedCalculator
What is the maximum speed a displacement vessel attain under ordinary conditions?
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Hull Resistance Calculator
Hull Resistance Calculator using Java Applet to display yacht design from user input values. This calculator is based on the equations and formulae in chapter 3 of "21st Century Multihulls" by Joseph Norwood Jr., available from Multihulls Magazine
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PHRF Calculator
How Fast Is Your Boat? Calculates Approximate Average Boat Speed and Seconds per Mile Speed Differences
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