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.

18.02.2008

From one Pacific to the next.

The Route de l'Or stretches along both sides of the American continent, where unusual sailing conditions are the norm. Lionel Lemonchois and his nine-man crew will have experienced similar weather phenomena only weeks apart. As suggested by its slowing speeds, Gitana 13 is readying for its second tangle with the Intertropical Convergence Zone (ITCZ…

par Gitana

The Route de l’Or stretches along both sides of the American continent, where unusual sailing conditions are the norm. Lionel Lemonchois and his nine-man crew will have experienced similar weather phenomena only weeks apart. As suggested by its slowing speeds, Gitana 13 is readying for its second tangle with the Intertropical Convergence Zone (ITCZ) and its second equator crossing.

The maxi-catamaran is located at 4°S, where the sailing is made difficult not by rough seas but by very high temperatures: “The sun is blazing hot. What a contrast…five days ago we were wrapped up in oilskins, wearing gloves and hats! To protect themselves during watch duty, the guys have rigged a system of sheets to lessen the impact of the sun and heat,” said Dominic Vittet.

The men of Gitana 13 have also made the most out of the relatively stable southeasterly breeze—meaning few maneuvers—to get some R and R. Their goal is to hit the always tricky and unpredictable doldrums in top form. For once they cross the equator, the maxi-catamaran’s deck will come alive: watch duty will be filled with frequent sail and direction changes and a greater level of concentration.

But as could be expected, the zone where the northern- and southern-hemisphere trade winds converge does not want to give up its secrets yet: “We’re right on in terms of our chosen timing, but things could get interesting fast. Because ahead of us lies a big area of light winds that we haven’t yet decided how to approach. For now we’re planning on going around the east side of it, but out here things changes so fast that we can’t say with any certainty,” said the onboard navigator.

Gitana 13’s strategy and the point at which it will enter the ITCZ will become clearer in the coming hours, and will depend on the doldrums’ activity. One thing seems certain: the maxi-catamaran fitted out by Baron Benjamin de Rothschild will return to northern latitudes in the next 24 hours. Lemonchois and his crew will have spent nearly 27 days in the southern hemisphere (they crossed the equator on the Atlantic side on 23 January at 8:24am). Their equator-to-equator time could have been five days shorter had the weather been more cooperative when Gitana 13 rounded Cape Horn.

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