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.

19.01.2008

Racing against the high-pressure system.

“In recent hours, the chop has turned to swells and we are being shaken around less.” These are the first words from Dominic Vittet, describing more comfortable sailing onboard Gitana 13..."

par Gitana

“In recent hours, the chop has turned to swells and we are being shaken around less.” These are the first words from Dominic Vittet, describing more comfortable sailing onboard Gitana 13…"

“But wind shifts and squalls dotting the maxi-catamaran’s route leave little time for Gitana Team to rest. The team is constantly adapting the sail configuration to suit the weather conditions: “on deck, all sails are being put to use. There have been a lot of maneuvers and sail changes to deal with. That’s why, since leaving New York, it’s been difficult to stick to the watch system. When conditions stabilize a bit, we’ll have to get back to it, since we have a long way to go to San Francisco!” said Lionel Lemonchois.

Continuing its southeasterly route, Gitana 13 is in a race against the Bermuda high-pressure system and the immediate threat of weak winds typical of such anticyclones. This is why they need to keep up the pace.

But the efforts of Lionel and his crew of nine should pay off soon, as Sylvain Mondon said yesterday: « Saturday evening…whispers of the northeast trades will finally reach the maxi-catamaran’s sails.”

The watch system on Gitana 13

Onboard the 33-meter maxi-catamaran equipped by Baron Benjamin de Rothschild, the ten men are divided into three watches of three: a helmsman, a trimmer and a bowman—more commonly called the No. 1. Under normal conditions, the watches take turns on the deck every three hours to get the most out of the rig. The tenth sailor, in charge of navigating and monitoring the weather, is off-watch. But he is regularly called on to give a helping hand during maneuvers.

Watch 1: Lionel Lemonchois (skipper) / Olivier Wroczynski / Florent Chastel
Watch 2: Ludovic Aglaor / Fred Le Maistre / David Boileau
Watch 3: Thierry Duprey du Vorsent / Nicolas Raynaud / Léopold Lucet
Off-watch: Dominic Vittet

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