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.

26.06.2013

War of nerves 50 miles from Plymouth.

par Gitana

The end of the third offshore leg of the Route des Princes is very much living up to expectations. Lamenting a deficit of thirty miles or so in relation to the leader yesterday afternoon, Sébastien Josse and his men were back in business this morning. Benefiting from the general stalling of the fleet, due to a windless zone offshore of the Scillies, the trimaran fitted out by Baron Benjamin de Rothschild had closed to within 5 miles of its adversary. At 1400 GMT, the separation had come down still further and Edmond de Rothschild was positioned within 1.6 miles of the Omani one-design. Whilst the leading MOD70s are just fifty miles or so from the finish, it would seem that there’s everything to play for: the shifty winds they’ve been battling in since last night, associated with the fact that they’re now punching tide, isn’t making life any easier on the water.

Thanks to an inshore option along the Irish coast as they passed Tuskar during the first night of the race, the crew of Oman Air thought they’d been successful in taking to their heels. The wind gods clearly had other ideas though. Indeed last night, as forecast by Sébastien Josse yesterday evening, the trimarans stalled in a windless zone on the approach to the Scillies and Bishop Rock lighthouse. This buffer zone enabled the men of Gitana Team to make up their deficit. Since then, Edmond de Rothschild and its rivals have been trying to make headway towards Eddystone lighthouse, the final course mark before the finish. However, the very shifty wind conditions are making life difficult for the sailors, who will just have to be patient over the final few miles of this third leg.

At the 1400 GMT ranking, Edmond de Rothschild was 52 miles from the finish line, set at the entrance to Plymouth Sound, and was just 1.6 miles astern of Oman Air. The latest ETA from Race Management indicated that the first MOD70s are likely to cross the finish line at around 1900 GMT. However, as its name suggests, this is just an estimate and things may change according to the weather conditions. This is particularly true given that the multihulls have the ability to create their own wind and the speeds can vary very quickly with just one or two knots’ difference in the sails.

Passage time at the Bishop Rock mark GMT

Oman Air-Musandam (Sidney Gavignet) at 0647 hours
Edmond de Rothschild (Sébastien Josse) at 0710 hours
Virbac-Paprec70 (Jean-Pierre Dick) at 0915 hours

Ranking for Offshore 3 on 26 June at 1400 GMT

Oman Air – Musandam (Sidney Gavignet), 50.6 miles from the finish
Edmond de Rothschild (Sébastien Josse), 1.6 miles behind the leader
Virbac Paprec 70 (Jean-Pierre Dick), 26.7 miles behind the leader

Spindrift Racing (Yann Guichard), DNS

The crew of Edmond de Rothschild in Offshore 3

Sébastien Josse / Charles Caudrelier / Thomas Rouxel / Antoine Koch / Jean-Christophe Mourniac / Florent Chastel

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