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.

23.11.2011

Definitive livery for the MOD Edmond de Rothschild Group.

Launched on 25 October 2011, the MOD 70 Edmond de Rothschild Group returned to Gitana Teams new technical base at the Kéroman site in Lorient this Wednesday. During the past month, the team led by the skipper Sébastien Josse, has had the opportunity to sail and trial their new steed on nine occasions, some of which were shared with Michel Desjoyeau…

par Gitana

For her sea trials, the Gitana Team were able to benefit from all types of weather conditions to get the measure of this latest craft fitted out by Baron Benjamin de Rothschild. They enjoyed calm spells, medium winds and more boisterous air flows of around 25 knots. The variety of conditions means that the team have really been able to get a feel for her: “It was a quick commissioning period. The boat is accessible as she’s simple to use and enables you to sail confidently. The MOD has been predominantly designed to compete in offshore races and the sea trials on her over recent weeks prove that she really fulfils her original brief. She doesn’t have too much sail area and provides you with a sense of safety, even in windy conditions. MOD still has a few details to sort out on our boat, but this will be complete during this short winter refit”, assured Sébastien Josse.

Over the course of a month, the 70-foot one-design in the colours of Edmond de Rothschild Group will undergo an ‘aesthetic’ refit. Indeed, on 25 October 2011, she was a plain, white boat void of any decoration when she was launched. From next week, Hubert Corfmat will begin his expert work according to plans drawn up by Jean-Baptiste Epron. The various members of the shore crew will make the most of the opportunity to give the interior fit-out a bit more attention too. The MOD Edmond de Rothschild Group will then return to the liquid element in early January as Sébastien Josse and his men have planned a thorough training programme during the first three months of 2012.

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