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## Hull Resistance Calculator

Awarded Calculator.com's Hot Calculator award, May 1998
The following calculator is based on the equations and formulae in chapter 3 of "21st Century Multihulls" by Joseph Norwood Jr., available from Multihulls Magazine

Chapter 3 deals with hull resistance. The aim is to derive simple mathematical formulae for the design of minimum-resistance hulls.
The formulae can be used either for non-planing displacement hulls or for multihull outriggers.
It is assumed that the front section has semi-elliptic plan and exponential profile, while the rear section has exponential plan and semi-elliptic profile. The theory may not be valid for sections which differ significantly from this.
The theory divides the hull into 2 sections of equal volume (but usually different length), makes calculations for each half, then adds them together.

WARNING - Do NOT use the AYRS edition of this book. It is full of typographical errors. The publisher's long-delayed 8-page errata sheet only covers some of them. You would not want YOUR boat to be "nearly" right apart from unknown, random errors, would you ?

The theory and equations are copyright to Joseph Norwood

The Java program is copyright to Fiona Sinclair e-mail to:e-mail to:fnsnclr@btinternet.com

Please wait patiently until a blank rectangle appears, then fill in the boxes and press Calculate.

To run this off-line, you need to download the following:

Fred.class,
Diagram.class,
Gadgets.class,
Matrix.class,
Paper.class,
Spread.class,
Wireframe.class
or (if you have a java compiler), the source
Fred.java

**PLEASE** send me some user feed-back.

To all the people who have asked why I called it fred.java:

It was named after Fred Schurch, who read the book but could not cope with the mathematics, then (very sensibly) mailed a discussion group asking for help. This program is dedicated to all other people who are in a similar situation.

e-mail to:fnsnclr@btinternet.com