One liveaboard's opinions on what separates a well-founded ocean-going sailboat from a coastal-cruising weekend boat, in design and particularly in equipment.
It is difficult to calculate, let alone get the input data, a boat?s roll moment of inertia, the best measure of dynamic stability. The author has created a method of comparing any boat's stability to a standard using available dimensions.
Choose from 650 cruising designs (or fill in data on any boat) and calculate its D/L, SA/D, Capsize Ratio, Hull Speed, and other performance ratios. Choose two boats at the same time, and they are compared.
Ultra Light Displacement Boats can weigh half what a conventional displacement hull does, exhibit twice the cruising speed , are easier to handle and less expensive for their size. The author talks about the downside to all this and his ideas for curing them.
One of the best discussions of the measurements and ratios that a builder or designer should furnish for you to evaluate a boats, and what they tell you about its performance and seaworthiness.