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.

03.04.2008

Pacific glides.

Since leaving San Francisco last Saturday at 22h45'45'' UT, Lionel Lemonchois and his crew have been racking up the miles at a steady pace – an average of over 21 knots – as they jump from one weather system to another. This strategy has paid off as, after just four days of racing, the 33 metres maxi-catamaran has a good lead over the reference tim…

par Gitana

Since leaving San Francisco last Saturday at 22h45’45” UT, Lionel Lemonchois and his crew have been racking up the miles at a steady pace – an average of over 21 knots – as they jump from one weather system to another. This strategy has paid off as, after just four days of racing, the 33 metres maxi-catamaran has a good lead over the reference time.

“Conditions are now ideal… We have been experiencing periods of sailing which have been considerably more pleasant over the past 24 hours. We have brilliant sunshine, increasingly calm seas and a twenty knot NE’ly breeze, which are currently enabling us to belt along at between 27 and 34 knots” confided Cyril Dardashti shortly after 2300 hours yesterday night.

No passage of “Diamond Head” for Gitana 13

In 2006, during its conclusive east to west crossing of the Pacific, Geronimo completed the course in three stages. In fact, weather conditions were such that Olivier de Kersauson and his crew were pushed onto a very S’ly course. This was so far south that the maxi-trimaran treated itself to two intermediary records (San Francisco / Honolulu then Honolulu / Yokohama) in addition to the North Pacific record crossing. For Lionel Lemonchois and his ten crew, the objective has always been to reduce the reference time for the whole course so the possibility of a passage between the Hawaiian Island was quickly moved to one side. The reasons for this are that the conditions Gitana 13 is currently benefiting from are enabling her to make headway towards the goal without having to round off her trajectory too much. “If the wind had guided us close to Honolulu we’d certainly have attempted the intermediary records, but we’re passing too far north of the archipelago to warrant adding additional miles. This is rather good news for the outright crossing record!” added Cyril. Positioned 320 miles north of the island of Maui yesterday night, the maxi-catamaran has since left the Hawaiian archipelago abeam of her, to port.

“This North Pacific crossing is a record you have to hunt down. As a result we haven’t eased off the pace since leaving San Francisco so we can get the very best out of Gitana 13!” Their efforts have been rewarded as, after just four days and a few hours on the counter, the maxi-catamaran equipped by Baron Benjamin de Rothschild has held a comfortable lead over Geronimo: 379 miles at the 0830 position report.

Today this NE’ly wind is set to hold as it clocks round progressively to the E and then the SE tomorrow. This rotation will accompany Lionel Lemonchois’ men in what will be their only day in a tradewind air flow during this record. According to Sylvain Mondon’s forecast, this fifth day at sea also promises to be one of the most productive since the start. Indeed, the combination of strong, established winds and fairly flat seas should enable Gitana 13 to lengthen her stride – the 600 miles covered in 24 hours are likely to be exceeded in principle – and they will be able to open up their lead still further over their virtual rival.

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