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.

06.11.2010

Gitana 11 back racing.

par Gitana

Aboard Gitana 11, yesterday is just a bad memory now. After ten long hours becalmed, watching helpless as his adversaries made good their escape, Yann Guichard has since found an established NE’ly wind of in excess of 20 knots. Fourth in the Ultimate Class, 500 miles from leader Franck Cammas and over 240 miles behind Francis Joyon in second place, the Gitana Team skipper knows it will be difficult to make up his deficit before Pointe-à-Pitre. However, until the finish line is crossed, there is still hope.

This morning, after a good rest, Yann Guichard described the long hours yesterday, powerless in the calm conditions: “It was a very long day yesterday… There was no or little wind and a slight sea which tossed the boat every which way. The sails were flogging so much that I really thought I would rip one or break battens. Added to that, in such conditions the automatic pilot totally lost the plot and often switched to error mode. As such I constantly had to be next to the helm and trimming. A situation like that is wearing on the nerves and there’s no chance of getting any kind of sleep” explained the skipper of Gitana 11. “I’ve found it quite difficult to accept the knock back I’ve had, especially given that I was right in the thick of the action yesterday morning. I’d really been on the attack the previous day on a reach prior to the passage through the front and I’d managed to make the shift over to the South as we were hoping. However, that’s life when you’re racing and you have to take it on board so you can quickly move onto other things and cast your mind forward to the future. I have 1,500 miles to go and I’m going to try to put in a good finish, whilst ensuring that I enjoy myself on the water.”

Looking at the average speeds being racked up by the top three Ultimate boats, it would be easy to think that life is a long, gentle river in the approach to the Caribbean arc. However, with 1,000 miles to the finish, the solo sailors are having to deal with conditions which aren’t always very comfortable for either the boat or the skipper. Aboard the maxi-trimaran fitted out by Baron Benjamin de Rothschild, the furthest East of the top four, Yann Guichard gave us an insight into the weather conditions: “reaching 10 to 15 knots during last night, the wind has freshened this morning to pump out 24 knots of breeze.” At the same time though, the seas are rough to heavy, with 2 to 3 metre waves building in size. Tricky conditions again for Gitana 11 then, which we should recall has a waterline which is ten metres shorter than her adversaries and which, as a result, doesn’t slip so well through the waves. This naturally explains the slight differences in speed observed between Gitana 11 and her closest rivals during the latest rankings.

To the great delight of her skipper, Gitana 11’s sails have regained their fullness, which is essential for the maxi-trimaran to make good headway to the finish. However, the next stage in the race isn’t forecast to be one of the easiest to negotiate as the weather conditions remain confused and this trend is being confirmed day by day.

Ranking for the Ultimate Category on 6th November at 0700 hours GMT
1- Groupama 3 some 1,026.3 miles from the finish
2- Idec 260.1 miles from the leader
3- Sodebo 272.4 miles astern
4- Gitana 11 some 508.8 miles astern
5- La Boite à Pizza 1076.8 miles astern
6- Défi Cancale 1,269.6 miles astern
7- Saint-Malo 2015 some 1,307.3 miles astern
Retirement- Côte d’Or II
Retirement- Oman Air Majan

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