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.

15.02.2008

A hive of computer activity.

par Gitana

The past day was exactly like the previous one. Same wind direction, same changes in trajectory to stay in the good wind, same speed…and this means 350 more miles logged toward San Francisco—which is now only a “Route du Rhum” away! In other words, another 4,400 miles to go. The only real difference with recent days was the appearance of real blue in the sky and the real sun. For the first time since reaching the Pacific Ocean, it’s been really hot on deck, and we’re not even that busy. The three men on watch are fully up to the task and don’t need the stand-by for help, except during jibes. So “watch” now means “three hours of free time,” a first since we started out on this journey (expect for our unavoidable pit-stop at Cape Horn).

Like usual, this free time flies by…and we’re well aware of this as the clock continues to run. What can the watch do apart from catch some rays? Actually, this activity isn’t one of our strong points. We’re much more adept at another activity, more in tune with the times: typing on the computer keyboard. And we have the equipment for it, with four computers onboard (two per hull). Last night, however, we experienced a slight panic: the network wasn’t working, we couldn’t use our computers. Big Dead Cloud has his own computer with the navigation software (MaxSea) and other routing programs that are constantly running. Next to it is a computer used for communications with land, for sending and receiving files and other email. This can be considered Cap’n Lionel’s computer, since that’s where he types! In the other hull, the port one, is the “cyber cafe,” which, as its name implies, is open to everyone, 24/7, thank you very much. With these two computers, one of which is used for photos and videos, this cyber cafe lives up to its name.

When our high-performance network went down, our IT person, none other than Zolive, had his work cut out for him. He spent a good part of his night there. After a short but useful phone call to our control tower in Trinité sur Mer, the problem was quickly resolved. Team Gitana struck again…we can continue forth while typing away on our little keyboards.

Goodbye

Nicolas Raynaud

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