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.

24.01.2008

Off the coast of Brazil.

Gitana 13 exited the Doldrums yesterday morning and since then has gradually picked up a more sustained air current in the form of easterly winds from the Saint Helena high-pressure system. On Thursday morning, the maxi-catamaran equipped by Baron Benjamin de Rothschild was sailing off Recife, on the northeast coast of Brazil.

par Gitana

With their equator crossing on Wednesday 23 January at 8:24am—after just 6 days, 14 hours and 52 minutes at sea—Lionel Lemonchois and his crew of nine have already delivered an impressive performance on the route leading Gitana 13 from New York to San Francisco.

For four of the ten men onboard, this incursion into the South Atlantic represents a first. For Lemonchois, however, this is his 13th equator crossing. Given the early hour of the crossing, Team Gitana did not perform any particular ritual when they crossed the “line” separating the northern and southern hemispheres. A mood of concentration and caution prevail among the crew.

The coming miles
Gitana 13’s average speed, which had slipped to 10-15 knots for more than 24 hours, climbed back above 20 knots last night. This pace should increase further during the day and remain there for around 48 hours. “The next stretch is shaping up pretty nicely for us, and the descent toward Cape Horn looks like it will be fast despite a tricky passage that we’ll have to negotiate in the next two days. We’ll be on a beam reach until we’re opposite Rio de Janeiro and the wind moves aft, but then it should be back abeam the rest of the way to the Horn,” said onboard navigator Dominic Vittet.

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