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.

29.11.2016

A chill on the horizon.

par Gitana

Isolated in the middle of the Indian Ocean, the solo sailors leading the way in the Vendée Globe are making headway beyond forty degrees South. The closest land to Sébastien Josse is situated 800 miles to his South-East and is none other than the French archipelago of Kerguelen, primarily populated by birds and marine mammals. The race has taken another turn for the sailors, who are making even more of an effort to strike a balance between speed and prudence with their piloting. Lying in third place, the skipper of Gitana Team is devoting his energy to making the most of a low pressure system that has been accompanying him on his journey since the latter part of the weekend.

The front is currently catching up with the Mono60 Edmond de Rothschild and the wind has begun its rotation. The 20-25 knot NW’ly has backed round to the West as it eases and Sébastien Josse gybed at midday. With 15 to 20 knots of breeze now, the sailor has also had to hoist more sail aloft and do some manoeuvring in what is a fairly hostile atmosphere.

Wrapped up under several layers of clothing, the body struggles to move about on deck. However, every action counts, even in this biting cold. Sébastien has to time to perfection every one of the steps necessary to quickly trim his boat. At the tail end of the front, the sea will likely be messier, but the visibility is improving, as the sailor shows us in his latest video today. That said, the temperatures remain very wintry…

Watch the video

His deficit in relation to Armel le Cléac’h (Banque Populaire VIII) and Alex Thomson (Hugo Boss) has stretched to 500 miles now. Indeed, ahead of the front, the two leaders are still benefiting from a little more breeze, but their pace should also slow up as the trio await the arrival of the next low pressure system, which is scheduled to put in an appearance at the end of the week.

Diving southwards

From now on, the line that marks the edge of the Antarctic Exclusion Zone is dropping southwards, to reach 50 degrees under the Kerguelen Islands. In this way, the scope of possibility is broadening for the sailor, for whom the route takes him towards the South-East.

It’s worth noting here that the closer a boat gets to the pole the shorter the distance required to circumnavigate the Antarctic. That said, venturing into such zones also becomes more dangerous due to the icebergs detaching themselves from the ice floe and drifting northwards, where they gradually melt as the water warms up. This is why an exclusion zone has been set up, which is forbidden to those competing in the Vendée Globe. In terms of the weather, there’s no point in getting too close to the southern continent as the downwind conditions are stronger further North, on the back of the low pressure systems. As ever then, it’s a question of compromise for the sailors.

After gybing at midday, the skipper of Gitana 16 has been making southing, with a good angle of attack in relation to the W’ly wind, which was propelling him along at 18.3 knots at 14:00 GMT. Edmond de Rothschild is likely to pass the longitude of the Kerguelen Islands within the next two days. Right now, the temperature should continue to drop, not just on deck but also down below since Sébastien is in contact with a carbon hull that is just millimetres thick and is slipping along on a sea that’s around five degrees.

Back in Europe, where the temperatures have also dipped over the past few days, we can kind of imagine what an ordeal this is for the sailor of Gitana Team. Aboard the Mono60 Edmond de Rothschild, the solo sailor can thankfully improve his environment using a little heating system that blasts a bit of warm air into his living space.

Ranking on 29 November at 14:00 GMT

Armel Le Cleac’h (Banque Populaire VIII) 15,623.2 miles from the finish
Alex Thomson (Hugo Boss) 20.85 miles behind the leader
Sébastien Josse (Edmond de Rothschild) 509.33 miles behind the leader
Jérémie Beyou (Maître CoQ) 986.24 miles behind the leader
Paul Meilhat (SMA) 994.29 miles behind the leader
Yann Eliès (Quéguiner Leucémie Espoir) 1,330.05 miles behind the leader
Jean-Pierre Dick (St Michel – Virbac) 1,901.01 miles behind the leader

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