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.

14.11.2003

Gitana at close quarters….

As expected, the accordion effect at the Doldrums is re-shuffling the cards in the pack. In continuing to reel in the miles at an average speed of more than 15.7 knots (29 km/h) over the last 24 hours, Gitana has managed to catch up on the leaders of the group following Groupama, bogged down in the inter-tropcial convergence zone which continues to…

par Gitana

s a result, Belgacom is just 96 miles (178 km) ahead at the first of the day’s position check-ins on Firday 14th November. Better still, overnight Gitana has gnawed away at Sodebo and now five boats are just ahead of the blue and white hulled trimaran. The way things are, anything is possible in a somewhat asthmatic wind at the Doldrums where how a boat sails is dependent upon the clouds. Should they avoid the big cumulonimbus giving rise to strong rain with or without wind ? Might it not be better to try and sneak in just along the very edge to use the peripheral winds ? As Loïck Peyron on Belgacom puts it : “there is no room for science ! ” when sailing in these waters. Whatever happens, there is no avoiding the Doldrums and today will turn out to be very important indeed particularly as Gitana is now up with the leaders. Anything is possible, even bearing in mind that Gitana finds the going tougher in light air than in a bit of a blow.

1 273 miles /2357 km to the finishing line…

Salvador de Bahia has come seriously closer over the last few days. Average speeds clocked up by Lionel Lemonchois and Marc Guessard are of course the reason why. “Top of the range” speeds in sailing-speak, speeds which highlight the ocean-going qualities of the first trimarna to have opted for a fully X-shaped structure and whose beams have a very high water clearance. There can be no doubt that these characteristics have demonstrated quite how efficient they are in a wind angle of 270° and in seas which are sometimes pretty rough in the tradewinds. The 551 mile day put in the day before yesterday is still on everyone’s mind and could turn out to be the best performance in this 6th edition of the Transat Jacques Vabre. That question will be answered in the next few days, as Groupama reckons that they will finish – all being well, which we wish them – on Sunday morning.

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