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.

01.02.2008

Lemaire Channel This Evening.

After more than 15 days at sea, Lionel Lemonchois and his nine-man crew are readying for one of the trickiest sections of their attempt at breaking the record between New York and San Francisco: Cape Horn. The maxi-catamaran, fitted out by Baron Benjamin de Rothschild, is currently headed toward Tierra del Fuego.

par Gitana

Clocked at 27.5 knots early yesterday afternoon, Gitana 13 temporarily dropped below 10 knots at the end of the day. These uneven average speeds are the result of the mixed weather systems along the boat’s route: “We are 25 miles off-shore, not far from Cap Blanco. All around us the seas are calm and there’s not a hint of air: dead calm!” said the skipper of the maxi-catamaran on Thursday at 7pm. But this situation shouldn’t last: “We are bracing for a strong north wind, which could climb to 30 knots, in the next few hours. Our goal will be to ride this breeze southward as fast as possible.”

As it approaches the southernmost point of South America, Gitana 13 is hugging the Patagonian coast in hopes of making it through Lemaire Channel without having to change tack. Lemonchois and his crew expect to reach this narrow strait at the end of the day.

But what’s really on the team’s mind is the Horn itself. Rounding this famous promontory from west to east is difficult enough, as storms there can really cause havoc. But approaching it “backwards” is even more complex: “At this point, we’re not sure we’ll be able to make it around Cape Horn on our first go. The window is very narrow, and given the forecast of strong winds, if we don’t take it Saturday morning, we may have to take shelter until 4 February.”

Lemaire Channel

This 24km-wide stretch of water separates Staten Island from the eastern tip of the Argentine part of Tierra del Fuego. It was discovered in 1616 by Jacob Le Maire—hence the name—and his fellow Dutchman Wilhem Schouten, during their expedition to map out a new commercial route between the Atlantic and Pacific Oceans. Several months later, these same men discovered the existence of Cape Horn, which they named in honor of their city of origin, the Dutch port Hoorne.

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