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.

16.11.2013

Offshore of Salvador de Bahia.

Shortly before the 0700 GMT ranking, the trimaran fitted out by Baron Benjamin de Rothschild passed the latitude of Salvador de Bahia; a city in north-eastern Brazil classified as a Unesco World Heritage Site that played host to four editions of the Transat Jacques Vabre from 2001 to 2007. Firmly installed at the front of the fleet since Cape Finis…

par Gitana

No respite

The ninth night at sea in the Transat Jacques Vabre wasn’t at all restful for the 70’ trimarans, which are continuing to lead the way into Itajaí. Making their way along the Brazilian coast since late yesterday afternoon, Sébastien Josse and Charles Caudrelier have had to adapt their trajectory in line with the south-easterly rotation of the wind. The atmosphere is coloured by piloting and refined trimming aboard the blue trimaran: “Overnight the wind oscillated between 18 and 20 knots in strength and began to back,” Antoine Koch explained. In fact, since Edmond de Rothschild’s exit from the Doldrums, the wind has been lifting them offshore of Brazil: “As forecast, it’s begun to shift round to the east, then it will back round to the north-east over the next 24 hours. In this transition phase, where Sébastien and Charles are the first to hit the different winds, there is a great deal of work on deck with a series of sail changes on the programme. The right choice of sail configuration is essential, especially on a reach, as it defines both the speed and the heading”, explained one of the onshore weather routers for the Edmond de Rothschild duo.

High-speed atmosphere for the Multi70s

In terms of speed, Edmond de Rothschild and Oman Air – Musandam have been sticklers for discipline since leaving Le Havre. Despite a boisterous start to the race, marked by some difficult sea conditions in the Bay of Biscay and during the passage around Cape Finisterre, the 70’ trimarans have been racking up some serious average speeds: 21.9 knots over the water to date! It’s worth noting in this analysis that in 2007, aboard their 60’ trimaran, Franck Cammas and Stève Ravussin took 10 days and 38 minutes to complete the course from Le Havre to Salvador de Bahia. This morning, as they passed just offshore of this Brazilian city, the indicator aboard the trimaran Edmond de Rothschild was displaying 8 days and 19 hours of racing. Such figures reflect the true enormity of the pace being kept up by the Josse – Caudrelier duo and their adversary in this 11^th edition of the Transat Jacques Vabre.

This Saturday 16 November, at the 0700 GMT ranking, Sébastien Josse and Charles Caudrelier were still holding onto a 54.7-mile lead over the Gavignet-Foxall duo. The trimaran fitted out by Baron Benjamin de Rothschild was positioned some 1,125 miles (2,083km) from the finish in Itajaí.

Ranking on Saturday 16 November at 0630 GMT:

Edmond de Rothschild (Josse-Caudrelier) 1,125.80 miles to go /28.00kt average over 2 hours
Oman Air-Musandam (Gavignet-Foxall) 54.75 miles behind the leader /27.70kt average over 2 hours

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