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.

12.11.2003

551 miles in 24 hours. Record beaten….

500 miles covered at 4h00 this morning, 514 by 6h00, 542 by 8h00 and 551 by 12h00, thus 1 020.5 km... Double record for Gitana today as the trimaran with the blue and white hulls has smashed the 24 hours record on this edition of the Transat Jacques Vabre.

par Gitana

500 miles covered at 4h00 this morning, 514 by 6h00, 542 by 8h00 and 551 by 12h00, thus 1 020.5 km… Double record for Gitana today as the trimaran with the blue and white hulls has smashed the 24 hours record on this edition of the Transat Jacques Vabre.

In so doing, she takes the Trophée Baume & Mercier for the day and becomes leader of the greatest distance covered since the start seven days ago. Marc Guessard : “We’re sailing at 20-30 knots downwind (at and angle of 140° to the wind for the purists among you) and the sea is not too tough going. But the whole trick is to find the right adjustments so that Gitana remains controllable. We have to be extra vigilant as we could easily come a cropper ” said the so-skipper during the official radio chat session today. “Inside it’s hell let lose. The noise is unbearable. You can’t hear yourself think. Outside it’s like being inside a carwash ! luckily we have our little bubble to shield us from the elements when we’re at the helm, otherwise it’d be impossible ! Thanks to Sylvain (Mondon, our router from Météo France) for his excellent analyses and recommendations since we left Le Havre and in particular since we called in at Porto Santo! “.

An average speed of more than 42 km/h…

“We’ve probably got 4-5 hours in these sorts of conditions. Things should calm down a bit after that. Till now, we’ve had ideal conditions to show this ocean-racing boat’s true potential and quite how powerful she is !”. Whilst the absolute 60-foot multihull record is 625 miles (1 157 km) in 24 hours, (Yvan Bourgnon on Bayer during the Québec Saint-Malo 2000), it ought to be pointed out that the 551 miles covered since midday yesterday were raced two up, not fully crewed. Sailing conditions which are incomparable : “We cannot leave the helm to the automatic pilot as it can’t cope with speeds like these. So we’re constantly taking turns at the helm and trimming. In 4-5 hours time, it’ll have calmed down a little.” Last but not least : 551 miles in 24 hours corresponds to an average speed of 23 knots 42.6 km/h! Now that commands respect!

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