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.

18.08.2008

Borneo bound.

par Gitana

Lionel Lemonchois and his men are beginning their 5th day at sea on their record attempt between Hong Kong and London. With less than 1,000 miles covered along the route since their departure last Thursday, the start of this Tea Route matches the forecasts made by the skipper of Gitana 13. Lionel Lemonchois knew these initial days of sailing wouldn’t be very productive in terms of making headway along the course. Fortunately though, the trend should soon be reversed as they hit the SE’ly tradewinds…

The first weekend at sea for the crew of Gitana 13 and the first laborious hours aboard the maxi-catamaran equipped by Baron Benjamin de Rothschild: “The past 36 hours have been a little tough. We’ve had to tack into short, breaking seas. These close-hauled tacks in 20 to 25 knots of breeze are never pleasant. This is particularly heightened aboard Gitana 13 by the fact that she detests this point of sail! Not only is there a reduced ‘comfort’ aspect but also these conditions aren’t really favourable for fine days in terms of sailing. Indeed, we are forced to reduce the sail area as much as possible in order that the boat doesn’t go too fast, and we avoid breakage” explained Dominic Vittet.

However, on the morning of Monday 18th August, the elements seem to be smiling on the sailors of Gitana Team once again: “For some hours the sailing has become more pleasant. We are on starboard tack, distancing ourselves from the Vietnamese coast by heading towards the island of Natuna, to the NW of Borneo. We’re finally making headway along the course, which is good for the morale amongst the crew. As regards ‘life on board’, this new found calm is enabling us to move about the boat more serenely, as well as catching up with a few hours of lost sleep in the chaotic seas” highlighted the onboard navigator, going on to say that “the temperatures are still fairly high so shorts remain part of our formal dress, however the numerous clouds which are dotted about the skies are making life more agreeable… for the time being!”

From tonight, the ten sailors of Gitana 13 will have to negotiate a transition zone involving a passage between the air flow created by a monsoon (SW’ly wind) and the SE’ly tradewinds. The crew of the maxi-catamaran in the colours of the LCF Rothschild Group will then have to deal with a zone of light winds for 24 hours or so. In this tricky exercise, they’ll be able to count on the lucidity and savoir-faire of Sylvain Mondon, the onshore weather router for Gitana Team.

Some figures

Gitana 13 left Hong Kong on Thursday 14th August at 07h55’32” (UT)
Saturday 16th August at 07h15 (UT), Gitana 13 was sailing at 13°N 45.53 N/113° 15.23 E
In 1990, Philippe Monnet took 67 days 10 hours and 26 minutes to complete this course between Hong Kong and London.

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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