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.

17.06.2013

In serried ranks in the stormy Bay of Biscay.

par Gitana

The whole of the Route des Princes’ fleet is now negotiating the Bay of Biscay under the influence of a powerful low. Having set off from Lisbon early yesterday afternoon, the MOD70s rounded Cape Finisterre this morning and are currently fronting up to some muscly conditions. As forecast, a solid westerly swell has been smashing headlong into the bows of the multihulls, making life aboard extremely uncomfortable and stressful. The trimaran fitted out by Baron Benjamin de Rothschild was lying in third place at the noon (GMT) position report in a group led by Spindrift Racing. The boats are bunched together given the hurdles still to come.

A few hours after what proved to be a fantastic start on the waters of the Tagus, where the one-design trimarans were able to show what they were made of amidst the puffs of air mixing things up on the river, the wind gods decided to play their first dirty trick on the leading boats. Whilst Spindrift Racing and Edmond de Rothschild battled it out at the front of the pack, they ended up floundering in the calm conditions just off the famous Guincho beach, just a few kilometres to the North-West of Cascais. Yann Guichard and his men managed to skilfully extract themselves whilst Sébastien Josse’s crew, positioned further inshore, took more time to hook up with fresh breeze again: “As per usual in the calm conditions, the back runners become the front runners!, Sébastien Josse explained ironically to his shore crew this lunchtime. Yesterday, on passing Guincho, Virbac Paprec and Prince de Bretagne were a bit off the pace and made the most of their position to sidestep the trap we’d fallen into and in so doing took the lead before nightfall.”

However, thanks to some great sailing last night when the wind lifted, enabling the crews to lengthen their stride a little, Sébastien Josse and his men got back into contention and crossed the latitude of Cape Finisterre in second position, within sight of their adversaries: “Yesterday evening the others got away from us a bit but we had a good night on a reach and managed to catch up with the group. We’re very happy with our position,” Charles Caudrelier said at the official radio link-up.

At midday, the one-designs were traversing a particularly tricky zone as they made their way around the eastern edge of the famous depression, which is currently livening things up in the Bay of Biscay: “It’s like a war zone outside! We’re making headway downwind under gennaker and, as expected, there’s a swell of nearly 3.5 metres hitting us head on. The big head seas are the main issue as the wind is only around 20 to 25 knots,” Sébastien Josse explained.In these muscly conditions, the trimarans are flying from wave to wave in a constant roar. However, the noise certainly isn’t the only stressful element aboard, as Charles Caudrelier reports: “the boat is suffering a fair bit due to this horrible sea state. We’re really leaping off the waves and you can hear cracking everywhere! The next three hours, before we gybe to the North-West, are going to be complicated.”

According to the latest forecasts, Edmond de Rothschild and its adversaries should reach the Fastnet tomorrow morning, Tuesday 18 June. Sylvie Viant, Race Director for the Route des Princes, is reckoning on an ETA at the legendary rock off southern Ireland of between 0800 and 1000 GMT.

Offshore 2 (Lisbon – Dublin) – Ranking on 17 June at 1200 GMT

Spindrift Racing (Yann Guichard) 560 miles to the goal
Musandam – Oman Air (Sidney Gavignet) 4.3 miles behind the leader
Edmond de Rothschild (Sébastien Josse) 5.1 miles behind the leader
Virbac Paprec 70 (Jean-Pierre Dick) 9.2 miles behind the leader

The crew of Edmond de Rothschild in Offshore 2 (Lisbon – Dublin)

Sébastien Josse (skipper)
Charles Caudrelier / Thomas Rouxel / Antoine Koch / Jean-Christophe Mourniac / Florent Chastel

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