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Sea Sure 2025

America's Cup - How long to build a catamaran?

by Derek Kelsall on 13 Apr 2008
Toria, built and sailed by Derek Kelsall the first multihull to win the Round Great Britain Race George Layton
In 1964, I was in Newport, R.I., USA, at the same time as the AC of that year, when it was a much more relaxed event. For example, Peter Scott was at the helm of the British challenger, having been chosen, just a few weeks before the start. I had arrived in Newport sailing the first none-ballasted yacht to compete in the Solo Trans Atlantic from Plymouth UK.

The AC and multihulls have come a long, long way since. I have been part of the multihull scene and followed the AC.

Lots of controversy in the AC, and multihulls have been shattering all previous sailing records. For everyone with a real interest in fast sailing, the AC has become the racing of 'carthorses'. It may be the premier sailing event in terms of money spent but it is a long way from being the state of the art of fast sailing.

About 25 years ago, I was one of a group from the UK and US who put forward a proposal for a multihull for the AC based on the argument that multihulls were the race machines on the water. I outlined a 70foot catamaran as our proposal. We got as far as a hearing thanks to one Graham Walker but it was clear that there was too much vested interest in mono technology by those making decisions, to every contemplate a change at that time.

Now is a ‘right time’, I suggest. The AC is put forward as the longest standing sporting event in the World. The definition of a sportsman is one who enjoys sport and 'behaves fairly and generously'! Those making the running today seem to have lost the plot entirely. Time, I suggest to consign the cup to its rightful place - in history - and abandon any further attempt to pull it out of the present mire.

Change

The present debacle presents a wonderful opportunity for change and change which would be good for the sport of sailing and for all concerned. The media would love it. I believe it would only take one investor or one syndicate to pick up on the multihull concept for a whole new event to be established which would outstrip the AC for spectacle, even if the AC got its act together for 90ft. monos. Many present syndicates, I believe, would welcome such a move.

As Malcolm Tennant says, it would be fast, close and exciting sailing as we have not before seen on short course racing. It would bring the amazing performances that are being achieved across oceans, into a venue where the battle for speed, using the power of the wind, can be watched by the World. I was about to write - Formula One, on the water, without using fuel – but it would make motor’s Formula One look like a boring procession.

How long to build a 90ft Multihull?

Fast, efficient building is something I have some knowledge and experience of. For two examples from many:

1. I built GB11, to win the first Whitbread Around the World Race. At 78 ft., it was the worlds largest sailing yacht in composites at the time. We started in a bare loft in Kent, with myself and a model yacht builder and traditional lofting in November. Princess Anne cracked the champagne bottle in May, six months later. I had 32 men working in shifts around the clock. (There was more to do on the water before ready to sail). Half were the crew and all had learnt boat building on the job. GB 11, with I believe six around the world races, 50+ Atlantic crossings and almost continuous sailing for many years has proven to be a great and reliable boat.

2. In Australia last year, during a 4 day hands-on KSS workshop, starting from scratch, we produced two panels which were put together and shaped into a long slim hull and a deck ready to simply be bonded to the hull. Again, not finished but the traditional approach to building would be no where in 4 days. The hull length was 15m.

I do know what is involved in large racing multihulls. I designed and was involved in the build in France, of the first 90ft + racing trimaran, William Saurin at 93’ x 50’ x 11.6 tonnes, having previously designed and built 80 foot tri GB111.

How? – forget conventional boat building of plugs and moulds. Using KSS (Kelsall Swiftbuild Sandwich) we would make a 90 foot by 8 foot table and from then on we would be making the boat, with every part of the structure starting on the table.

KSS is: All resin infusion, carbon epoxy uses same technique, least weight for strength, no compromise of performance and simple to post cure. Given an experienced and well motivated build crew, the facilities, the organization to get the rig, deck fittings etc., etc., etc., underway and, of course, the funds, a 90 foot catamaran would be a straightforward project to complete in less than six months. I see no complication in the design, which has to be done with the build method in mind.

It would be less than half the structure of GB11 in simple to handle separate parts. I know a lot of people who would pull out all the stops to meet such a challenge.

Derek Kelsall.
Kelsall Catamarans Ltd.
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