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.

20.08.2008

Gitana 13 en route to the Java Sea.

par Gitana

The maxi-catamaran in the colours of the LCF Rothschild Group has been sailing in southern latitudes since last night. After a fifth and rather unproductive day at sea, Lionel Lemonchois and his nine crew crossed the equator shortly before midnight (UT). This passage into the southern hemisphere, combined with the establishing of the SE’ly tradewinds marks a new start in the record attempt between Hong Kong and London. This Wednesday morning, the Sunda Strait was just 200 miles ahead of the bows of Gitana 13.

The crew of the maxi-catamaran equipped by Baron Benjamin de Rothschild has had to patiently await the beneficial SE’ly tradewinds, an air flow which is synonymous with considerable acceleration. Indeed, Lionel Lemonchois and his men have had to extract themselves from a zone of light winds, which were barring their route: “Last night we finally hit the SE’ly tradewinds, after a day which I can best describe as laborious. We opted to cross the Doldrums, which stretched between Borneo and Singapore, on the Indonesian side. We stayed with the breeze the whole time but some big clouds, which are fairly characteristic of this zone, blocked the establishing of the tradewinds and hence the hour of our deliverance… We just had to be patient!” confided Dominic Vittet from the chart table of the 33 metre vessel.

However, this patience has been rewarded since Gitana 13 is now making good headway, full and by, at over 20 knots on its way to the Java Sea. In order to get there they will adopt the Gaspar Strait; a narrow passage which separates the Indonesian islands of Bangka and Belintung: “We’re finally having some fun! The SE’ly tradewind has kicked in and is pushing us along towards the Gaspar Strait at what is at last a speed worthy of Gitana 13. It’s a fairly narrow passage – 2 miles wide – and pretty shallow, but the current conditions are enabling us to adopt this route, which will nevertheless reduce our course towards the Sunda Strait” explained the onboard navigator.

The day ahead will consist of a passage across the Java Sea; a zone famed for its numerous oil rigs for the extraction of oil and gas, as well as the many fishing boats which pass across it. This, added to the proximity of the coast will require a good dose of vigilance on the part of the ten sailors aboard the maxi-catamaran. Finally, it shouldn’t be forgotten that the crew of Gitana 13 will have to negotiate this passage under the cover of darkness; Lionel Lemonchois and his men being 5 hours ahead of us.

Some figures

Gitana 13 left Hong Kong on Thursday 14th August at 07h55’32” (UT)
Wednesday 20th August at 07h15 (UT), Gitana 13 was sailing at 02°13.32 S / 107°19.92 E

Watch No1: Lionel Lemonchois (Skipper / watch leader / helmsman) / Olivier Wroczynski (trimmer /head of computers and power) / David Boileau (Bowman / head of deck fittings)

Watch No.2: Ludovic Aglaor (watch leader / helmsman) / Laurent Mermod (trimmer) / Ronan Le Goff (Bowman)

Watch No.3: Pascal Blouin (Watch leader / helmsman) / Ronan Guérin (trimmer) / Léopold Lucet (No.1, head of supplies and doctor)

Outside the watch system: Dominic Vittet (navigator)

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