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.

18.11.2016

We’re accelerating, heading southbound!.

par Gitana

In his message yesterday evening, the solo sailor shared the deafening noise inside the belly of the Mono60 Edmond de Rothschild from the area where he tries to sleep. Making its way down the length of Brazil, the 18.28-metre hull is surfing along an isobaric wave at an average of 20 knots. Gitana 16 is marching along towards a low pressure front which will carry the Vendée Globe leaders to the gateway into the Deep South. Some 100 miles ahead of the fleet, Briton Alex Thomson is already benefiting from a steadier breeze, thus stretching away from his pursuers Armel Le Cléac’h and Sébastien Josse. This weekend, the speeds are likely to set the speedos spinning, some observers even announcing that the 24-hour record might fall.

Positioned the furthest offshore of the lead boats, Edmond de Rothschild is powering along in a NE’ly trade wind, which has picked up to 18-20 knots. “We’re accelerating, heading southbound! We’re trying to hook onto a cold front, which will give us a ride down towards the Cape of Good Hope,” admitted Sébastien from the massive carbon sounding box in which he’s living, working and trying hard to sleep. The skipper is keeping up with the pace, which is set to intensify still further over the coming hours. The wake of the Mono60 Edmond de Rothschild is currently marking out a fine curve down the South Atlantic, parallel to that of Banque Populaire VIII, positioned further over to the West.

Speed takes priority as the train won’t wait.

Soon they’ll catch up with the stormy low pressure system that was created in the bay of Rio de Janeiro and is set to sweep across the whole of the Atlantic on its way towards the roaring forties. The planets are aligned for speed demons since there’s a sharp acceleration on the cards with the boats sailing at an angle of between 110 and 140° to the true wind, which is ideal for the Imocas. Radically geared towards these points of sail which really see her power up, the Hugo Boss rocket that’s making headway 100 miles further South, is likely to be the first to hit the low. Slightly further back down the track, the chasing pack will then gradually feel the effects of the acceleration in turn. At that point, they’ll be hurtling along in manageable seas, at the leading edge of the front. As such, everything should come together to enable them to make very fast headway. It’s down to each skipper now to strike a balance and set the bar in the place they deem to be the best.

Watch the video

Today’s figures

At 14:00 GMT, Edmond de Rothschild in 3rd place
116.3 miles behind the leader Alex Thomson
Distance covered over the past 24 hours: 428.96 miles at an average speed of 17.9 knots
Distance covered over the ground since the start: 4,382.85 miles at an average speed of 15.1 knots

Ranking on 18 November at 14:00 GMT

1. Alex Thomson (Hugo Boss) 20,398.4 miles from the finish
2. Armel Le Cleac’h (Banque Populaire VIII) 107.0 miles behind the leader
3. Sébastien Josse (Edmond de Rothschild) 116.3 miles behind the leader
4. Vincent Riou (PRB) 155.6 miles behind the leader
5. Morgan Lagravière (Safran) 215.4 miles behind the leader
6. Paul Meilhat (SMA) 228.4 miles behind the leader
7. Jérémie Beyou (Maître CoQ) 313.7 miles behind the leader
8. Yann Eliès (Quéguiner Leucémie Espoir) 501.9 miles behind the leader
9. Jean Le Cam (Finistère Mer Vent) 650.7 miles behind the leader
…

* 534.48 miles covered in 24hrs, at an average speed of 22.27 knots, in 2012 by François Gabart aboard Macif.

Retourner aux articles

Heritage