Retractable Y-shaped foils, adjustable in three dimensions

Inspired by the appendages of the America's Cup foiling monohulls, these Y-shaped foils have a wingspan of over 5 metres. They are designed to generate powerful lift, increase power and offer a wide range of adjustments to optimise flight at every point of sail and in all conditions. Beyond their impressive size, these foils feature many unique innovations.

Revolutionary U-shaped rudders

These are probably the most visually striking innovations on the new Maxi Edmond de Rothschild. To fly high above rough seas while maintaining control, the team wanted very long rudders that would remain in contact with the water. The challenge is that longer rudders tend to flex under load, severely affecting steering and the efficiency of their lifting surfaces. A new geometry was needed to give these appendages maximum stiffness, resist cavitation and ultimately improve control of the boat and make better use of its power. The result is a set of U-shaped rudders over 4 metres long, a metre longer than those on Gitana 17. Their shape, reminiscent of a tripod or an inverted π, is only the visible part of what makes them so distinctive.

A daggerboard optimised to stabilise the boat and limit cavitation

With its wide span, the daggerboard resembles an aircraft tail assembly, with two adjustable flaps: one on the vertical section and the other on the horizontal section, the distinctive “manta-ray wing”. On Gitana 18, the innovation is to position this wing behind the vertical part of the appendage, rather than directly beneath it, to minimise flow disturbance and cavitation.

Rig: adjustable spreaders to control mainsail power while sailing

Gitana 18’s mast is 1.50 metres taller than its predecessor’s. The boom is also shorter, creating a more slender sail plan. The major innovation is a set of spreaders that can be adjusted while sailing to bend the mast fore and aft. Actuated by hydraulic rams, these spreaders can pivot through 35 degrees to adjust the bend in the middle of the mast. This unprecedented system allows the sailor to control mainsail power: adding depth in light winds to take off sooner, or flattening the sail to reduce power at high speed or in strong winds. Adjusting the depth, and therefore the power, of the mainsail can also save a solo sailor time and energy by reducing the need for risky manoeuvres or headsail changes.

Central hull:
an integrated, structural coachroof

The naval architects and Gitana design team wanted an exceptionally stiff, structurally robust platform. This applies both to the floats, which must withstand heavy loads from the foils and rudders, and to the central hull, which is subject to torsion. The enclosed coachroof is integrated into the hull and contributes to its structural strength. Inside, the cockpit brings all sail-handling controls together, with ergonomics shaped by many hours of design and development. The coachroof also stands out for the number and size of its windows. This configuration meets the visibility requirements of the Ultim class rules and gives sailors the best possible view to keep a visual watch.

24.06.2006

Tough conditions.

Two rounds were completed at Marseilles today in the 4th stage of the Cafe Ambassador Multi Cup, the Grand Prix de Marseilles. Gitana 11 clinched two creditable second-place finishes, while the crew of Gitana 12, who are still discovering the boat in this configuration, have had to cope with demanding conditions unsuited to this point on their lear…

par Gitana

Loick Peyron, Gitana 11 skipper

“We’ve still got a lot of room for improvement but things are going really well on board and we were quite consistent today. On the coast, we simply needed to do what Geant has done. Even though we didn’t manage to catch up with her, we did well, especially as just as we were fighting to get back even more, we got a rubbish bin wrapped around our rudder… no, not a bag, an actual bin! Obviously, it considerably reduced our performance, as having a bin stuck to your rudder is far from ideal. On the second stage, it was a little more hairy but we finished well. Just like yesterday evening, we are equal with Geant, so it promises to be a very interesting contest tomorrow. I’m loving it.”

Thierry Duprey du Vorsent, Gitana 12 skipper

“It was a hard day for us, very hard even. There was more wind than yesterday and, fatally in these conditions, the lack of training is glaringly obvious. It was noticeable immediately in terms of manoeuvring, organisation in the cockpit, coordination between the helm and tactics… basically all the mechanics of good functioning. We need to cut out the tactical and technical errors, which we made dozens of today. On the coast, changing the situation is complicated, as we were against the wind and even Groupama couldn’t make up enough ground on the front two. The positive aspect is that given that we had the “good fortune” to undergo a full overhaul in the spring, we won’t need to take the boat back out this summer and will be able to use that time for intensive crew and solo training. So between now and then, we’re going to dig in as, in the short term, there’s even more wind forecast for this area.”

Provisional general rankings:

1- Groupama / Franck Cammas 28 points
2- Géant / Michel Desjoyeaux 23 points
3- Gitana 11 / Loick Peyron 23 points
4- Gitana 12 / Thierry Duprey du Vorsent 16 points

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