Preliminary Design – Ratios, Coefficients, Feasibility & Midsection Development
Revised 08/14/2008 – Copyright 2008
Minimum Tools for This Lesson if Using Computer Assisted Design
Rhinoceros® (commonly known as Rhino) Version 4.0 or later
14 Spline Weights
Planimeter
See drawings from Lesson Two A
Choosing the Speed to Length Ratio
Hull Speed
Choosing Prismatic Coefficient
Choosing or Not Choosing Displacement to Length Ratio
Midsection Development Principles
Defining the Midsection – By the Visual Method
Defining the Midsection – Using Prismatic Coefficient and Displacement to Length Ratio
First Trial on Scantlings
First Trial on Ballast
First Trial on Sail Area and Engine Horsepower
Laws of Mechanical Similitude
Useful Proportional Ratios