We've all been watching the development of the AC72, trying to get a good feel for what kind of design it is, what the limits are, where the risks lie.
We've seen ETNZ handle their beast with aplomb.
We've seen Oracle Racing devoured.
But now, for the first time, we have a real inside evaluation of the AC72. It comes courtesy of Loick Peyron, who is working with Artemis Racing and has probably sailed more miles in more multihull designs than just about any sailor on the planet.
Peyron knows what he is talking about, so when he talks it is worth listening. And, after four outings with Artemis' AC72, he has offered a bracingly honest and intriguing evaluation of the AC72 design. And in his view
it is very, very, tricky:
Loïck Peyron: “We have sailed aboard her four times and she is extremely powerful. That isn’t that much of a surprise for me, as I have spent a long time looking at the design of these machines, but it is still all very impressive. To sum up, these are boats that aren’t that wide or that big, but which have a very powerful “engine”. To get an idea of what I mean, it’s a bit like putting a V8 or V12 engine on a go-kart. So it is no easy matter making use of all that power. We saw what can happen when Oracle capsized. These machines require caution. My job was to be something like a test pilot on this AC72. I’m here to find just how far we can take things and avoid those hairy moments, when the boat starts to dig in, for example. Already by the second or third trip, I found myself out there on the helm and I can say it’s fascinating.”
What is the difference from an AC45?
LP: “They don’t have that much in common. Proportionally, the AC72s are much more unstable. Because looking at the base, the engine is that much more powerful. You need to add on a third more power to an AC45 to get some sort of idea. And then, there is the sheer scale: everything is that much heavier, including the wing, of course and the centre of gravity is not that well placed, as it is higher up. On top of that, there is a lot of inertia… the “engine” is extremely powerful, but above all she is always in gear. And of course, you can’t take in a reef…”
“Yes. Of all the boats I have sailed on, she is the trickiest. When you start flying downwind, it is very impressive and that is one of the major questions that interest us: you need to find a compromise, knowing when to fly, but above all without using too much energy to do that. For me, flying aircraft for more than twenty years, it is very interesting. After each day out there sailing, we need to spend several days ashore fine-tuning the boat on every level. For the moment, we are just working on boat number 1, but we have already got some ideas about the second one. With the first one, it’s rather like racing with 30kg on your shoulders. Once the second boat is on the water, that weight won’t be there any more.”
“Very. For the moment, we’re taking it step by step deliberately, so we’re not out there looking for the highest speed. But we have already reached 26 knots in just 10 knots of wind.”