Ker Design have been investing… heavily. Using the example of his new McConaghy-built Class 40 Jason Ker explains a fresh approach to yacht design

Introduction

After being immersed in America’s Cup design, with both ACC and then AC90 yachts, Ker Yacht Design refocused its attention on designs for private clients. Meanwhile, our commitment to R&D remained constant and it is this that has recently been bearing fruit with the remarkable new optimisation capabilities we have developed.

Our new Class 40 design for Team Concise (teamconcise.com), which is now entering series production at McConaghy in China, is our first project to take full advantage of this technology. We have now set our sights on taking Mini Maxi and Open 60 design to new heights.

Hull development
I am sometimes asked why, at a time when computers are used extensively in the design of yachts, all boats don’t look the same. The answer I used to give was that while there might be a perfect solution for a given race or set of races, based on a set of weather predictions, there is still an infinitely large number of shapes to choose from. The typical ‘shape optimisation’ approach, used by designers since the advent of tank testing, is to change one parameter at a time to determine its effect on performance – thus creeping towards a faster solution. With the adoption of Computational Fluid Dynamics (CFD) the same approach continued, albeit with an increase in the numbers of models.

The typical result of this ‘linear optimisation’ approach renders most designs linear variants of a successful shape, a so-called ‘typeform’. However, in reality the shape parameters have coupled effects causing the real design space to be infinitely larger than that explored by linear optimisation or using enhanced sequential techniques such as genetic algorithms.

Occasionally a different and better typeform is discovered, through intelligent judgment or by accident, creating a new typeform that makes hulls designed around the previous one obsolete.