How to use your yacht’s hull shape

Whether you have a long keel or twin keel rudders, there will be pros and cons when it comes to performance. Toby Heppell explores three boats’ differences for Yachting Monthly.

Ask any sailor to explain the differing characteristics of hull shapes and they will be full of opinions about the advantages and disadvantages of one boat or another. But these views are usually clouded by past experience and bias.

To a degree the vast array of opinions on offer about any given design choice support the need for such a variety of hull shapes, keel choices, rudder types and so on. Every yacht ever designed is right for someone out there in the world.

Given these deeply held biases, it can be difficult to get accurate representations of what the compromises and benefits that come from certain boat designs actually are.

Taking a data-driven approach to this question can be a very difficult task indeed, so naturally YM set out to do just that.

We set an objective to take three types of boat, broadly reflecting eras of design, and put them through their paces on the water in an attempt to find the idiosyncrasies inherent in each design and measure them.

Although far from a comprehensive overview of all design options available, the three representative styles we settled on were: a long keel with keel-hung rudder, a medium displacement fin keel and skeg, and a modern, wide hull with twin rudders.

We felt these gave a representation of the broad direction in design over the last 50 years, though there are many permutations of hull and keel that were not included.

In an ideal world, we’d have three boats built to the same length at the same time, by the same designer with only the differences listed above to speak of.

However, our proposal for commissioning, designing, building, and sailing three brand new yachts for a comparative test was inexplicably shot down by senior management, so we did the next best thing and called up three owners, each with different style of boat to come to Lymington for the day. – Full report