{"id":161950,"date":"2026-02-10T06:42:07","date_gmt":"2026-02-10T06:42:07","guid":{"rendered":"https:\/\/www.yachtingworld.com\/?p=161950"},"modified":"2026-02-12T08:37:19","modified_gmt":"2026-02-12T08:37:19","slug":"the-smartest-boat-ever-built-500-sensors-custom-autopilots-and-the-future-of-foiling","status":"publish","type":"post","link":"https:\/\/www.yachtingworld.com\/yachts-and-gear\/the-smartest-boat-ever-built-500-sensors-custom-autopilots-and-the-future-of-foiling-161950","title":{"rendered":"The smartest boat ever built? 500 sensors, custom autopilots, and the future of foiling"},"content":"Lorient is the Hollywood of ocean racing. Like the movie factory of Los Angeles, the Brittany port is a seemingly single-purpose town that draws dreamers. And just as Hollywood is La La Land, so Lorient attracts some of the most outlandish projects in sailing.\r\n\r\nThe La Ter river is dotted with small yachts bobbing on moorings, awaiting gentle adventures in the tiny creeks and sandy beaches of southern Morbihan. But the estuary\u2019s north shore is different. This is home to the concrete wonderland of La Base, a former U-boat submarine base that is today\u2019s epicentre of ocean racing. A walk around the pontoons here is a chance to window-shop the most extreme offshore technology.\r\n\r\nGitana\u2019s team base is in prime position, a nearly 2,000m2 boat shed with Bond-lair-esque rolling walls to shutter its secrets. Since 2022 the work inside has been kept closed and confidential, but in early December the base was thrown open to unveil Gitana 18, the newest 100ft foiling trimaran.\r\n\r\n[caption id=\"attachment_161962\" align=\"alignnone\" width=\"630\"]\"\" The Y-foils cant on giant swinging arms[\/caption]\r\n

A passion for sailing<\/h2>\r\nGitana is the racing stable of the Rothschild family, a banking dynasty synonymous with generational wealth on an epic scale. Their passion for sailing has equally been handed down, and Gitana 18 marks 150 years of the family\u2019s deep involvement in yachting, currently spearheaded by matriarch Ariane de Rothschild.\r\n\r\nThis history shapes the fundamental reason for building a new boat. Unlike most corporate sponsorships, Gitana 18 is not built to score column inches. She is not even entirely built to win. Gitana 17<\/a>, the previous Ultim<\/a> launched in 2017 and the first giant tri to take flight, has basically already won most things.\r\n\r\n\u201cWhat we\u2019re doing here is really on another level, but it\u2019s also going to be a risk,\u201d explains project manager S\u00e9bastien Saison. \u201cIf we had wanted to be 100% sure that we\u2019re going to win the next Route du Rhum<\/a> in 2026 we would have gone safer. It would have just been a bit of an evolution. But we know that\u2019s not the future.\u201d\r\n\r\nIt was the opportunity to do something extraordinary that drove the project. \u201cOtherwise we wouldn\u2019t have had the chance to build a new boat.\r\n\r\n[caption id=\"attachment_161959\" align=\"alignnone\" width=\"630\"]\"\" The Y-foils also have two adjustable flaps[\/caption]\r\n\r\n\u201cAriane de Rothschild was quite clear about it: if they invest, and if we are to do a new boat, it has to be disruptive. It has to be another level up,\u201d recalls Saison.\r\n\r\n\u201cSo it was part of the scope of work, to say \u2018Okay, do a new boat, but show me you can do something really crazy.\u2019 Obviously for a naval architect or an engineer, it\u2019s always nice to hear! But we couldn\u2019t have known at the beginning what we would have ended up with.\u201d\r\n\r\nSo Gitana 18 isn\u2019t just about collecting trophies. It\u2019s about the creation of an epic. In pursuit of the two great achievements that eluded her predecessor \u2013 solo and crewed non-stop around the world records \u2013 it\u2019s a boat built for experimentation on a grand scale. And that is why it looks quite so mad.\r\n\r\n[caption id=\"attachment_161954\" align=\"alignnone\" width=\"630\"]\"\" The 121ft mast can be bent underway using hydraulic rams around the spreaders[\/caption]\r\n

Full flight<\/h2>\r\nThe most obviously extraordinary things about Gitana 18 are the appendages. The goal of this boat is 100% air-time, flying across oceans at 40+ knots, and the resultant foils are phenomenal in both scale and shape.\r\n\r\nWhile the previous generation Ultims have L-foils that plunge through their outer hulls before curving inwards, Gitana 18 sports giant T- or Y-foils on swinging arms that lift up between the crossbeams. Beneath the central hull is a huge \u2018skate wing\u2019 T-board. And most baffling of all are the rudders, which are like no other rudders seen before. They have a \u2018U\u2019 or A-frame shape with twin chords and a horizontal base plate.\r\n\r\nThe foils, which the team refer to as Y-foils, show a clear lineage from those on the AC75s<\/a>, though Gitana\u2019s will lift inwards to meet the Ultim maximum beam rule. Their wings span more than 5m, the bulb 2m long.\r\n\r\nOne key target is to enable the boat to take off earlier. Skipper Charles Caudrelier explained that the old Gitana needed to be sailing at around 22-24 knots to accelerate and take flight. These new foils could reduce that to less than 20 knots of boatspeed, in potentially as little as 10 knots of windspeed.\r\n\r\nAt the upper end of the range, cavitation is another problem they\u2019ve worked to address. \u201cWhen I reached 37 knots on Gitana 17, all the appendages started to cavitate. So that means lots of drag, and also lots of damage on the foils. They degrade very quickly. It\u2019s a nightmare,\u201d Caudrelier explained.\r\n\r\n[caption id=\"attachment_161968\" align=\"alignnone\" width=\"630\"]\"\" The radical A-frame rudders are deeper, thinner, but theoretically more resistant to deformation[\/caption]\r\n\r\n\u201cWe pushed the limit with a second generation of foils up to 40-42 knots. But in surfing conditions sometimes you can\u2019t stop the boat. You have a big wave, plus a gust, and you go to 45, 47 knots \u2013 and then all the boat vibrates, and you know you\u2019re damaging them. You know that at the end of the race, you\u2019ll have lost 10%, 20%, even 30% of the performance of the boat because of degradation. It starts to impact the paint. Then it goes through to the carbon. In the end, you can break the foil because you\u2019ve lost skin on skin. At the end of the race around the planet, I was sailing at 70% of my performance in perfect conditions because the foil was completely destroyed.\r\n\r\n\u201cThat\u2019s also why we like canting foils because another problem before was that my windward foil was up, but it was hitting the water and damaged a lot in the elbow. By canting them, we can pull it up off the water and they\u2019ll have no contact.\r\n\r\n\u201cWe expect these foils to degrade much less. Then at the end of the race, we\u2019ll still be at 100% \u2013 if we don\u2019t meet a rock or a piece of wood. That\u2019s a game changer.\u201d\r\n\r\n[caption id=\"attachment_161969\" align=\"alignnone\" width=\"630\"]\"\" The in-house simulator was used to process vast amounts of data and help sailors visualise the boat\u2019s behaviour[\/caption]\r\n

Minutely trimmed<\/h2>\r\nThe \u2018skate wing\u2019 T-board beneath the boat is now a massive, sculptural piece of metal (the team won\u2019t disclose which one) which will be more resistant to this degradation. It is 30% bigger than the previous boat\u2019s. The switch from carbon to metal is because, while metal is a little less efficient, it offers a better overall balance of stiffness against both torsion and bending.\r\n\r\nThe T-board version we were allowed to see (but not photograph) had a tattoo etched in the surface which will carry fibre optic sensors to measure how much this metal is contorting under the sea - just some of the 500 sensors Gitana 18 will carry (double the number on 17). Designer Guillaume Verdier described the boat as like a creature capable of telling its crew when it is in pain.\r\n\r\n[caption id=\"attachment_161966\" align=\"alignnone\" width=\"630\"]\"\" Cyril Dardashti, team manager; owner Ariane de Rothschild; and skipper Charles Caudrelier at Gitana 18\u2019s grand unveiling. Photo: Marie Rouge\/Gitana SA[\/caption]\r\n\r\nThe metal skate wing should also be more robust in case of collisions. The central bulb contains pinger technology to warn marine mammals of its approach.\r\n\r\nThe physics driving these foil shapes will require whoever is piloting to trim complex underwater interactions over multiple planes, often while sailing solo. This a very different prospect to a full-time flight controller minutely trimming the foils of an AC75 over a windward-leeward Cup course. The Y-foils alone can be canted, raked, and each wing has independently adjustable flaps on the trailing edges.\r\n\r\n\u201cYou have to change the trim of the [foil] depending on sea state, because the sea state makes a big difference in speed,\u201d explains Caudrelier. \u201cSo if the sea state is flat, the wing is horizontal. If the sea state is larger, we have to put it more vertical because it helps when the boat accelerates. The boat starts to fly higher because the foils lift more. Then part of the wing goes in the air, so the foils lift less.\r\n\r\n\u201cThat is the game, which is very complicated.\u201d\r\n\r\n[caption id=\"attachment_161965\" align=\"alignnone\" width=\"630\"]\"\" The grand unveiling. Photo: Marie Rouge\/Gitana SA[\/caption]\r\n

The flexi-rig<\/h2>\r\nAnother tool at Caudrelier\u2019s disposal will be the rig, shipped over from Southern Spars \u2013 the first the New Zealand builders have made for the Ultim class.\r\n\r\nThe 121ft spar is capable of impressive levels of flex. The problem, Caudrelier explains, is that when you are building speed and power to take off, particularly in lighter airs, you need camber in your rig. But when in flight mode you need it flattened off to depower.\r\n\r\nThe solution is a mast which can be bent, with the spreader angles flexing by up to 35\u00b0 to create camber in the middle of the section. Rams control the power \u2013 one on each spreader \u2013 in a system which can be handled by a solo sailor, rather like cranking on the Cunningham on a dinghy or windsurfer rig.\r\n\r\nArticle continues below...<\/em>\r\n\r\n[collection]\r\n\r\nThe ability to depower should also reduce the number of headsail changes or reefs required. \u201cI can very quickly change the angle of the spreaders, then I can adapt my power to the wing and to the speed of the boat. That\u2019s very, very fast,\u201d notes Caudrelier.\r\n\r\nDespite the intimidating forces involved, he says the rig is actually simple to handle. \u201cBut to do it on a canting wing mast, and such a big mast \u2013 that has never been done before. And how to manage it with only one guy on board? That took a lot of brain hours!\u201d\r\n\r\n[caption id=\"attachment_161957\" align=\"alignnone\" width=\"630\"]\"\" Gitana 18 was moved under cover of darkness. Photo: Eloi Stichelbaut\/polaRYSE\/Gitana SA[\/caption]\r\n

Radical Rudders<\/h2>\r\nControl is what led to the creation of the outlandish rudders, the most unique feature of Gitana 18. To improve steerage when flying at faster speeds, high above the waves, the team wanted to lengthen the rudders. The problem is that the huge loads they are subjected to, means they can deform, twist and shear, leading to sudden loss of control.\r\n\r\nThe new U-shaped rudders do not rotate \u2013 instead they have trailing edge flaps on each vertical chord, which provide steerage like an aeroplane wing. Each rudder also has a horizontal elevator, which in turn has an adjustable flap to control trim. This rigid structure enables the rudders to be much deeper \u2013 at over 4m they are a metre longer than on Gitana 17 \u2013 and resistant to cavitation. They are also thinner hence, somewhat counterintuitively given their shape, there is no drag penalty.\r\n\r\nBut they\u2019ve never been made before. There has been no tank testing and no scale models built \u2013 just a lot of CFD and data analysis, and enormous trust in the process.\r\n\r\nThe problem, Saison explains, is that when you are designing something that has never been done, there is no data to work from. \u201cWhen we started designing those rudders, the software for designing them didn\u2019t exist. The simulator didn\u2019t understand them and physically couldn\u2019t calculate them. So in the same time as we\u2019ve invented those rudders, we had to invent a new code for the simulator. We had to invent a new programme to calculate the structure. Obviously, those programmes are not as well proven as the one for the foils. So that brings another little level of stress.\u201d\r\n\r\nCaudrelier is confident. \u201cOn a car, you can have a super engine, but in Formula 1 today sometimes you lose a race because of your tyres. You can have the best car, but if your tyres are not good, you cannot be very accurate and you have to reduce your speed. It was exactly the same on Gitana 17. Sometimes we felt the rudders were overloaded. We knew that if we didn\u2019t reduce the load, we were going to damage them, or it\u2019s going to twist and we\u2019d lose control. More control means you can push harder.\u201d\r\n\r\n[caption id=\"attachment_161961\" align=\"alignnone\" width=\"320\"]\"\" The boat was precision built at CDK Technoloiges in Lorient, with up to 80% made in an autoclave. Photo: G Le Corre\/polaRYSE\/Gitana SA[\/caption]\r\n

Visualisation<\/h2>\r\nBecause this rudder shape had never been tried before, even the most high-tech autopilots weren\u2019t suitable. So, in an ambitious side quest, Gitana developed its own. This also helped keep a project of such complexity top secret, in a town where everybody works in the same industry.\r\n\r\nOne key weapon was their in-house simulator. Derived from the Team New Zealand America\u2019s Cup sim, Gitana has now developed an offshore foiling simulator tool like no other. Over three years Caudrelier says they \u2018sailed\u2019 for thousands of hours on it, initially verifying the vast data accumulated from eight years of optimising Gitana 17, and focussing on improving how the simulator handled variances of sea state.\r\n\r\nCaudrelier explained: \u201cOver the last three years, the improvement in the sim has been huge \u2013 because we\u2019ve had no boat, we\u2019ve spent hours and hours \u2018sailing\u2019 the simulator and developing it. Now it\u2019s really accurate.\r\n\u201cBefore it was just numbers and no sensation, no feeling. Now we can really test the foils, rudder, everything, and give our feedback to the designer. It\u2019s completely changed the way we work.\u201d\r\n\r\n[caption id=\"attachment_161960\" align=\"alignnone\" width=\"630\"]\"\" 200,000 man hours have gone into Gitana 18\u2019s construction. Photo: G Le Corre\/polaRYSE\/Gitana SA[\/caption]\r\n\r\nThe autopilot was subject to some eight months of daily testing. \u201cIt works like a helmsman,\u201d Caudrelier enthuses. \u201cIt understands how the boat works, can adjust the height of the flight, can visualise the boat in 3D and anticipate its movements. In terms of performance, it\u2019s amazing what we can achieve with it.\u201d The major limitations will be what the class rules permit in terms of automation.\r\n\r\nThe cockpit of this 100ft goliath share some features with the latest IMOCAs, particularly Charlie Dalin\u2019s Vend\u00e9e winning Macif. Like Dalin, Caudrelier requested his living space be behind the working cockpit area. The cockpit is also fully enclosed. But once inside, what strikes you most are the irregular-shaped portholes punched through the roof and sidewalls. Gitana 18 is the first new trimaran built to meet the latest Ultim rule on visibility, and their positioning was created with Caudrelier to enable him to maintain a lookout, and view sail trim.\r\n\r\n[caption id=\"attachment_161967\" align=\"alignnone\" width=\"630\"]\"\" S\u00e9bastien Saison (left), Caudrelier (seated) and team discuss the finer details of construction mid-build. Photo: Eloi Stichelbaut\/polaRYSE\/Gitana SA[\/caption]\r\n

Anything goes<\/h2>\r\nGitana 18 was a year in conceptual development before build even began. The team adopted a \u2018try anything\u2019 approach, working with the most innovative and free-thinking designer of a generation in Guillaume Verdier. \u201cThe whole idea of the boat \u2013 and Guillaume loves working like that \u2013 is to say, don\u2019t think about the problems now. Think about what would be the most crazy thing,\u201d explains Saison. \u201cThe rudders are one example. If you say, \u2018Oh, it\u2019s going to be super complicated. How are we going to attach them to the boat?\u2019 If you start thinking like that, you don\u2019t do it.\u201d\r\n\r\nVerdier himself commented: \u201cbeing so lucky to create such a work of art in a career is rare.\u201d\r\n\r\nWhile the project\u2019s ambition was unlimited, that doesn\u2019t mean the budget was, as Ariane de Rothschild explained: \u201cWhen we work under tension and pressure is when we work better. So it\u2019s very important to put in budget caps that are reasonable.\u201d\r\n\r\n[caption id=\"attachment_161970\" align=\"alignnone\" width=\"630\"]\"\" Caudrelier (left) working in VR goggles to visualise the cockpit layout, sight lines etc.[\/caption]\r\n\r\nBut reasonable is relative. They will likely never disclose exactly how much this extraordinary project cost, but one team member did emphasise that their 30-person operation runs at quite a bit less than an America\u2019s Cup campaign. Meanwhile the previous boat was listed for sale at \u20ac15million, so the answer likely lies somewhere in the very big space between \u20ac15million and \u20ac50million.\r\n\r\nFar more important is what it can do. \u201cThe top speed, I think we\u2019ll manage above 55 knots, which is a lot for a big boat. But that\u2019s not what we\u2019re looking for,\u201d explains Saison. \u201cWhat we\u2019d like is to have average speeds above of 40 knots all the time.\r\n\r\n\u201cThe around the world time is very hard to say because already on the previous boat, it was 35, 38 days. If you had perfect routing, I\u2019m sure that the times would be just about 30 days now, but it\u2019s never going to happen because of the weather. But if you can go at 40 knots average around the world, it would be 32 or 33 days.\u201d\r\n\r\nAnd that would be something truly extraordinary.\r\n\r\n
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Lorient is the Hollywood of ocean racing. Like the movie factory of Los Angeles, the Brittany port is a seemingly single-purpose town that draws dreamers. And just as Hollywood is La La Land, so Lorient attracts some of the most outlandish projects in sailing. The La Ter river is dotted with small yachts bobbing on moorings, awaiting gentle adventures in the tiny creeks and sandy beaches of southern Morbihan. But the estuary\u2019s north shore is different. This is home to the concrete wonderland of La Base, a former U-boat submarine base that is today\u2019s epicentre of ocean racing. A walk around the pontoons here is a chance to window-shop the most extreme offshore technology. Gitana\u2019s team base is in prime position, a nearly 2,000m2 boat shed with Bond-lair-esque rolling walls to shutter its secrets. Since 2022 the work inside has been kept closed and confidential, but in early December the base was thrown open to unveil Gitana 18, the newest 100ft foiling trimaran. A passion for sailing Gitana is the racing stable of the Rothschild family, a banking dynasty synonymous with generational wealth on an epic scale. Their passion for sailing has equally been handed down, and Gitana 18 marks 150 years of the family\u2019s deep involvement in yachting, currently spearheaded by matriarch Ariane de Rothschild. This history shapes the fundamental reason for building a new boat. Unlike most corporate sponsorships, Gitana 18 is not built to score column inches. She is not even entirely built to win. Gitana 17, the previous Ultim launched in 2017 and the first giant tri to take flight, has basically already won most things. \u201cWhat we\u2019re doing here is really on another level, but it\u2019s also going to be a risk,\u201d explains project manager S\u00e9bastien Saison. \u201cIf we had wanted to be 100% sure that we\u2019re going to win the next Route du Rhum in 2026 we would have gone safer. It would have just been a bit of an evolution. But we know that\u2019s not the future.\u201d It was the opportunity to do something extraordinary that drove the project. \u201cOtherwise we wouldn\u2019t have had the chance to build a new boat. \u201cAriane de Rothschild was quite clear about it: if they invest, and if we are to do a new boat, it has to be disruptive. It has to be another level up,\u201d recalls Saison. \u201cSo it was part of the scope of work, to say \u2018Okay, do a new boat, but show me you can do something really crazy.\u2019 Obviously for a naval architect or an engineer, it\u2019s always nice to hear! But we couldn\u2019t have known at the beginning what we would have ended up with.\u201d So Gitana 18 isn\u2019t just about collecting trophies. It\u2019s about the creation of an epic. In pursuit of the two great achievements that eluded her predecessor \u2013 solo and crewed non-stop around the world records \u2013 it\u2019s a boat built for experimentation on a grand scale. And that is why it looks quite so mad. …Continue reading »<\/a><\/p>\n","protected":false},"author":1571,"featured_media":161957,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3117,159],"tags":[3116,1633,1522],"review_manufacturer":[],"acf":[],"introduction":null,"_links":{"self":[{"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/posts\/161950"}],"collection":[{"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/users\/1571"}],"replies":[{"embeddable":true,"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/comments?post=161950"}],"version-history":[{"count":2,"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/posts\/161950\/revisions"}],"predecessor-version":[{"id":161974,"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/posts\/161950\/revisions\/161974"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/media\/161957"}],"wp:attachment":[{"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/media?parent=161950"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/categories?post=161950"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/tags?post=161950"},{"taxonomy":"review_manufacturer","embeddable":true,"href":"https:\/\/www.yachtingworld.com\/wp-json\/wp\/v2\/review_manufacturer?post=161950"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}