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.

12.11.2007

Done with the doldrums?.

While race positions remain unchanged at 16:00 this afternoon, morale was on the rise aboard Gitana 11, with the trimaran speeding along at 20 knots after seemingly emerging rather nicely from the doldrums in which Banque Populaire, her direct rival for second place, is still mired.

par Gitana

Yann Guichard, co-skipper of Gitana 11:

“It’s still a bit lively in terms of squalls, but there’s light at the end of the tunnel, which bodes pretty well. We opted to get round the anticyclone in the doldrums. It was a bit of a gamble but it paid off, as the doldrums were pretty extensive. The further you go to the east, the more you have an open angle to go down towards Bahia. We didn’t really know where we were going, but luckily the door was open. We’re almost out of it now and travelling at an average of nearly 20 knots. That should speed up tonight and we’ll be clear. We’re a bit tired as it was a long night… In the squalls, it’s a case of constantly having to change the sails: one minute, you’re rolling and the next unrolling!”

Among the monohulls, Gitana Eighty is still 4th and the suspense is total concerning the different options now emerging. To stay in the centre or veer to the west or the east…That is the question..

Loïck Peyron, in the mid-day radio chat :

“Everything’s going well and it’s really hot. The wind is very tricky to manage as it’s so changeable, in terms of both force and direction. We’re gybing downwind, which means we’re doing plenty of miles, but not on the direct route, unfortunately! The race should get going again in 24 hours on passing Cape Verde and between now and then, we’re all just watching each other out of the corner of our eyes. We have been sailing on watch with the auto pilot, so it’s good training for solo racing!”

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