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.

03.11.2010

Positioning game in the tradewinds.

It will soon be three days since the fleet competing in this ninth Route du Rhum – La Banque Postale left Saint Malo. In the match between the Ultimate class, the maxi-trimaran fitted out by Baron Benjamin de Rothschild is continuing to round to the South of the Azores High. Since yesterday Yann Guichard has been slipping along downwind in a NE’ly…

par Gitana

As each ranking comes in and after three nights at sea, the options taken by each skipper from the NW tip of Brittany are revealing an initial scenario. At this stage in the race, the advantage has gone to those on a S’ly option, a course choice selected by the majority of the solo sailors in the Ultimate Class. At the front of the fleet, Groupama 3, who is constantly racking up an average speed in excess of 20 knots, has shown her pursuers a clean pair of heels. Behind her though, the race is very much living up to expectations and it’s a really close-fought battle between those to the North – Sodeb’O and Majan – and those to the South – Idec and Gitana 11. At the first ranking this Wednesday morning, the advantage had gone back to those on a tradewind course. Indeed Francis Joyon has made it into the top 3, while Yann Guichard has positioned himself between him and Sydney Gavignet in 4th position. The skipper of Gitana Team should be able to improve on this position over the course of the day given the differences in VMG (Velocity Made Good) observed. At 0300 hours GMT, Gitana 11 was making the best compromise with a speed of 18.9 knots compared with 10.6 for Thomas Coville, 5.7 for Oman and also 15.5 and 17.5 knots respectively for Idec and Groupama.

Sylvain Mondon, Gitana Team’s onshore router, is following this Route du Rhum with the usual commitment at all times. With his eyes fixed on his computer day and night to view the weather forecasts for the Atlantic, Sylvain is compiling, analysing and proposing information for Gitana 11 to trace the best possible trajectory, together with help from Billy Besson. This morning he explained Yann Guichard’s intermediate position to us, as he is now sailing at a latitude between Idec and Groupama: “Midway through yesterday, the wind was beginning to ease again. In fact the zone of high pressure was expanding again, which wasn’t exactly forecast in the grib files. In this way we decided to set a course to the SE so as to distance ourselves from the high pressure and get back into a steadier breeze. Idec took the same option but didn’t push his boat as hard as Gitana 11… Last night the wind was again showing signs of dying back so we upped the pace again as we weren’t keen to fall into overly light winds.” These two position shifts, made over the course of Tuesday, were important as they’re today enabling Gitana 11 to benefit from a better angle to the wind than her closest rival.

After over 60 hours at sea and no less than 800 miles made good, the maxi-trimaran fitted out by Baran Benjamin de Rothschild is into her stride. As the days go by, Yann Guichard is dividing his time between trimming, piloting the boat, discussions with his shore crew as well as managing his life as a solo sailor: “Everything’s going very smoothly aboard Gitana 11. I’m into my stride and the days are passing by without me really realising. I’m having an absolute ball, especially since we began to slip along in the tradewinds. I’m managing to eat well. I tucked into the freeze-dried dishes yesterday and my chunks of sleep are becoming a bit more organised, propped up on my pouffe in the companionway to the cockpit. I’m lucky to be able to concentrate on getting the boat making headway as Sylvain Mondon and Billy Besson are racking their brains for me on shore, even though the big decisions are the subject of more collective discussions” explained the skipper of Gitana 11.

Aboard the blue and yellow maxi-trimaran, today’s aim will be to make headway as fast as possible whilst retaining a good angle for tackling the next stage of the course. The future is shaping up to be highly uncertain, especially towards the end of the week.

Ranking for the Ultimate Category on 3rd November at 0400 hours
1- Groupama 3 some 2493.1 miles from the finish
2- Sodebo 210.9 miles behind the leader
3- Idec 211.6 miles astern
4- Gitana 11 some 236.6 miles astern
5- Oman Air Majan 248.2 miles astern
6- La Boite à Pizza 468.9 miles astern
7- Défi Cancale 544.5 miles astern
8- Saint-Malo 2015 some 570.4 miles astern
Retirement – Côte d’Or II

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