Result

Develop a production foiler Moth that would be 100 per cent competitive against one-off designs... most thought the idea far fetched. Andrew McDougall has proved them wrong

Designing the 'KA'
The KA Boat, as it was first called before it became Bladerider, could easily have been a new Prowler design in partnership with Fastacraft's John Ilett; however, John dropped out early in the negotiations, later admitting to me that he had thought that we were mainly just blowing hot air! With John out of the frame I became even more motivated to design the very best boat I was capable of. A boat that used all my experience of designing, sailing and building Moths and windsurfers… and also computer programming. A boat that would work as well as possible out of the box, that would stay competitive for as long as possible, and that would if possible achieve the Holy Grail of Moth sailing: the foiling tack.

General hull shape
1. The new hull had to have its minimum resistance at 6-8kt of hull speed, the speed at which we could lift onto the foils; 8kt is the most critical speed, as the hull's weight is now being borne almost entirely by the foils. Hence, we needed to optimise the displacement shape for the lift-off speed, but for a displacement of around half the all-up weight (because the foils are now contributing significantly).
2. Low-riding performance needed to be reasonable.

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