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.

16.11.2013

Less than 1,000 miles to go.

par Gitana

At the 1600 GMT position report, the two 70’ trimarans were less than 1,000 miles from the finish. However, the Josse Caudrelier duo and their adversaries are all too aware that there is still a way to go before they reach Itajaí and, most importantly, the route is full of pitfalls. For the time being, the trimaran fitted out by Baron Benjamin de Rothschild is still making headway at high speed (between 25 and 30 knots) in an easterly tradewind. However, the strength of the breeze is fluctuating wildly due to the numerous lines of squalls, which the one-designs are encountering along the way.

Thirty-two miles separated Edmond de Rothschild from her pursuer Oman Air – Musandam this Saturday at 1600 GMT. However, it comes as no surprise to Sébastien Josse that there is so little between them, as he explained this lunchtime: “Given the upcoming weather conditions, it’s highly likely that the two boats will bunch up again over the next 24 hours. That’s how it goes. You just have to grin and bear it and stay focused and clear-headed for the end of the race.”

Indeed the weather situation is far from simple. Itajaí has to be earned and Sébastien Josse and Charles Caudrelier will have to negotiate a set of tricky and particularly strategic zones before they make it to the Brazilian city. “There’s a big low, which has formed over the Brazilian coast and is heading off on a merry-go-round into the Deep South around Antarctica. Associated with this low is a substantial cold front, which is breaking up the Saint Helena High and is stretching out as far as the coasts and the bay of Rio. To the south of the front, there’s no wind and it’s very stormy,” explained the router for the Edmond de Rothschild duo.

The numerous squalls currently rolling about offshore of Brazil certainly aren’t making life easy for the leaders and may well cost them dearly. Early this afternoon, the Edmond de Rothschild duo were dramatically slowed beneath one such squall, which largely explains the miles conceded between the 1000 GMT ranking and that of 1300 hours.

After 10 days of racing and what has been a more than steady pace since the start, the fatigue is all-pervasive aboard the 70’ trimarans. This lunchtime, during the daily radio session with Press HQ in Paris, Sidney Gavignet’s voice left us in no doubt of that. “The chaps are keeping to the rhythm set by their boat,” Sébastien Josse admitted, before being called up on deck by Charles Caudrelier. And yet, with the end of the course drawing nearer, the suspense promises to be thrilling, albeit a testing time for the sailors.

Today’s routing is still indicating an ETA in Itajaí of Tuesday morning, but from his HQ in La Rochelle Antoine Koch was keen to emphasise the lack of reliability in any predictions until such time as the cold front taking shape in front of the two Transat Jacques Vabre scouts is in their wake.

Ranking on Saturday 16 November at 1530 GMT:

1 – Edmond de Rothschild (Josse-Caudrelier) 928.80 miles to go /27.60kt average over 2 hours

2 – Oman Air-Musandam (Gavignet-Foxall) 31.75 miles behind the leader /28.40kt average over 2 hours

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