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.

10.11.2013

Skirting the Azores High.

par Gitana

Already three days have passed since the Transat Jacques Vabre fleet left Le Havre. And already the two Multi70s, which have been leading the way towards Itajaí (Brazil), are tackling their Atlantic crossing. After the heavy, chaotic seas encountered in the Bay of Biscay and right the way down the coast bordering the Iberian Peninsula, Sébastien Josse and Charles Caudrelier were finally benefiting from some good downwind conditions this morning. Indeed, the trimaran fitted out by Baron Benjamin de Rothschild is currently sailing under the influence of the Azores High. Last night the Gitana Team duo negotiated the southern fringe of this high pressure and were beginning to sense the first signs of the tradewinds of the northern hemisphere this morning.

“On a strategic level, they’ve had a good night!” Antoine Koch began. The router then went on to explain the stakes at play in the 3^rd night at sea: “It was necessary to get sufficiently close to the zone of high pressure to hit the favourable north-easterly wind shift. This rotation was very important as it means we’re lined up nicely for the next stage of the race.” In this way, the trimaran fitted out by Baron Benjamin de Rothschild linked together a series of gybes along the southern edge of the Azores High.

At 0800 GMT this Sunday, Sébastien Josse described the current sailing conditions for Edmond de Rothschild: “It’s grey, we haven’t yet caught a glimpse of the sun and there are cross seas in part. However, the atmosphere has already warmed up substantially aboard and we’ve been able to remove our neoprene gloves and our hats. The north-easterly wind is now well established and we’ve got around 12 to 15 knots of breeze. All the sails are on deck. The wind is set to build over the course of the afternoon and from that point we should really be in the thick of the tradewind system.”

It won’t be long then before the Edmond de Rothschild duo hit the tradewind expressway with some lengthy sessions gliding downwind on the cards for the coming days. However, that doesn’t mean it will be all ‘plain sailing’ for our two sailors as the conditions that await them will call for the utmost vigilance at all times as well as some top-quality piloting.

24 hours ago, at the 0700 GMT ranking, the two Multi70s were neck and neck with just a mile separating Edmond de Rothschild and Oman Air – Musandam. Yesterday however, after perfectly negotiating the passage around Cape Finisterre, Sébastien Josse and Charles Caudrelier benefited from a lift along the Spanish and then Portuguese coast to lengthen their stride and rack up some precious miles ahead of their adversary; some 34.6 miles to be precise according to the 0700 GMT ranking this Sunday.

Please note that there are six official position reports a day at the rate of one report every 3 hours from 0400 hours. No position reports are produced overnight and from 1900 GMT, a position blackout is observed. Timing of the official rankings: 0400, 0700, 1000, 1300, 1600 and 1900 hours GMT.

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