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.

01.11.2006

Yann Guichard’s weather update.

With Gitana 11 still well out in front at 08:00 this morning, Yann Guichard, one of Lionel Lemonchois' two routers along with Sylvain Mondon, talks about the weather options at the start of this breathtaking race.

par Gitana

With Gitana 11 still well out in front at 08:00 this morning, Yann Guichard, one of Lionel Lemonchois’ two routers along with Sylvain Mondon, talks about the weather options at the start of this breathtaking race.

Yann Guichard:

“Right from the start, there was a front to pick up on to the southwest of Ireland and we always wanted to stay as south as possible in relation to the rest of the fleet so as to anticipate the rotation of the wind after this front. It amounted to a slightly riskier option than climbing to the northwest because there was a little less wind, but Lionel has sailed really well and been able to keep up a brisk pace. When the wind did switch, Gitana 11 was one of the first to gybe a bit ahead of this front which was breaking up. Since Tuesday morning, he has kept all the canvass up (mainsail and gennaker) and is really shifting. He gybed just after the midday position and is therefore the furthest forward, to the southwest of the rest of the fleet.
He now needs to negotiate a low-pressure front located east of the Azores: the trimarans are going to pass to its north but it’s necessary to know whether to shave the area of low pressure or to drop down further west. The archipelago won’t be easy to cross and it’s still too early to know the best level to tackle it at, late in the afternoon on Wednesday. This is because there will be squalls while passing the islands with gusts of over 30 knots. The Azores are therefore a key point in the race as you’ve got the Bermuda anticyclone to the west and between these areas of high pressure and the Azores low-pressure front, there’s a little gap off the coast of Flores, i.e. an area of unstable and low wind. Consequently, it’s essential to deal well with Wednesday, as it will to a large extent determine what follows: whether to go east of Santa Maria, east of Terceira, west of Faial, north of Flores… After that, the routes will be fixed until the trade winds, with the finish in Guadeloupe expected on 7 or 8 November.”

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