dog. That was a huge jump - 59 knots is an amazing average. At the end of the run, really what stopped it was that the leeward float was flying too high. it's like flying the hull too high on a catamaran, it slows you down because your drive vectors are starting to go up in the air. I still think we could go faster again. SRM: Piloting a sailboat at high speed is not for the faint hearted - what are the most dangerous aspects? Paul Larsen: There are lots of scenarios. Before that last record on the final day, we had pulled the whole boat apart to check everything. It took a few days but we did it. There is such a push to save weight and windage by using thin lines. You do your own destructive testing on them but in the end you are talking fractions of knots and you just think 'go and put the big line on there' - it means a lot more to the end story than a crash; you just can't afford to crash it. Every time I sling the safety harness around me I am thinking do I want to be wearing this or not - I am always quite uncertain about that. As you go faster you are aware of the danger of the whole thing, but that tends to be the thought you have before the run. When you get in the cockpit, you switch off to all that and concentrate on the run itself. You are aware that you are there to make some pretty bold calls and you are not there to be shy of the boat. If you don't do a good run, you are going to have to do it again until you do manage a good run, so you might as well get it right straight off. If we had rolled the boat on one of the last runs we did it would be lethal, no doubt about it. My head is sticking out of the cockpit and I'm strapped into the boat. If the boat rolled then your head would be slammed against the side of the cockpit, the helmet would likely be ripped off and it would be lethal. There is no maybe about it. It would be like rolling a Formula 1 car with no roll bars fitted. So the next big thing we plan to do with that boat before we sail it again or I let anyone else sail it is to look hard at the safety. As the speeds go up we think the loads on things like the stays that hold the beam in place should be quite low - actually they should almost be neutral at hight speed. Yet, when we pulled the boat apart and looked at the internal shackles they were elongated. Failure there would let the boat fold back and roll like the first boat did.
Then there are external factors like hitting a seal or a dolphin in the shallows. We had a seal jump in front of the boat at slow speed and hit one of the wires. At high speed that would cause a horrific crash. The foils hold the boat down into the water so if you hit something and lost a foil then the back of the boat would be lofted up into the air. If the boat goes more than six degrees bow down then it will nosedive. Because the boat is already travelling sideways it would be like spear fishing with a banana or sliding your car sideways into a tree. SRM:What are your plans now you have smashed the record? Can you apply what you have created to other projects? Paul Larsen: A lot of people look at the foils as the breakthrough, but the thing that enabled all of this to work was the initial concept of having no overturning forces. That fundamentally gives us the power. The foil is good but it take a lot of power to drag it through the water by conventional foil standards. The benefit is that it doesn't have that glass ceiling - if you pour more power into the equation, it just keeps going up the drag curve - it doesn't go exponential on you and that allows you to start playing around with the shapes. But if you just look at the foils and not at what engine you need to drive them then you are not going to get anywhere near the right speeds. To see that boat at peak speed, you could actually cleat off and let go of the steering wheel because it was just in perfect balance. That 'engine' more than the foils is what we will look at taking forward. We think that this concept can lead to some pretty exciting boats and some really neat solutions to the problems that we see in other boats. When you look at other high performance boats right now, they are pretty messy, in that there is a lot of drag involved. They are using all the tricks they can with foils and the way they do their bows, to stop the overturning and pitching forces. A boat like ours just gets rid of them completely. We had to go and smash a speed record to really prove how strong the concept is. Doing the speed sailing was all about giving the concept credibility where it was undeniable. It's funny now that some people kind of miss the point and say that it is an impractical boat. Actually they have no idea how ridiculously impractical that boat is, but it proves a point extremely well. Now we can make it practical by looking at the concepts and how they can be
July 2013 57
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