With the tenth edition of the Vendeé Globe well underway and the field passing the mid-journey point, the vastness of the southern Pacific Ocean now lies ahead of the contenders. Although three participants already had to bail out and with Damien Seguin´s IMOCA, where a chain plate at the bow section ripped out, Pip Hare´s mast came down and one of Sebastien Simon´s foils broke, “only” a few real major technical incidents (but luckily no human harm) happened so far: Let´s cross fingers! Talking of foils though …
At least in the media, this is one of the big “races” within the race: Will the all-out foil-designed boats be able to do something against the dominating non-foilers? Especially Jean Le Cam´s TOUT COMMENCE EN FINISTERE is of particular interest: A completely new built IMOCA that intentionally does not feature any foils but rather bets on the good old daggerboard. Racing is about the skippers, their tactics and also luck. But it is as well very clearly technological warfare, it is engineering pinnacle and a test arena for more or less revolutionary (or risky?) concepts. So, let´s ask one of those guys who are deeply involved with this.
Talking to Quentin Lucet of VPLP
NO FRILLS SAILING | Lars Reisberg: “Quentin, please describe your position and task area at VPLP naval architects.”
VPLP | Quentin Lucet: “Salut Lars. So, first of all I am a naval architect and partner here at VPLP. I started back in 2005 when the very first IMOCA was on the drawing bords. Back then this was a result from the collaboration between VPLP and Verdier. Fast forward to 2024: With the current Vendée Globe we are now witnessing the fifth generation of IMOCA-designs from our office. Over the evolution of this class, foils were introduced to the fleet some ten years ago, marking the first time IMOCA-boats featured this groundbreaking technology.”
NO FRILLS SAILING | Lars Reisberg: “To start, let´s begin easy: What is the principle function of foils on a sailing boat?”
VPLP | Quentin Lucet: “You see, foils on a sailing yacht have three principal functions. First is to generate lift. Secondly, they are reducing the hull’s contact with water and thereby significantly decreasing the drag. And third, by lifting the boat out of the water, they create artificially an overall displacement “lighter” than that from a classic Archimedean yacht. By generating hydrodynamic lift underwater and the lifting out of the water, those boats will therefore achieve higher speeds for any given wind conditions.”
NO FRILLS SAILING | Lars Reisberg: “I remember seeing hydrofoil vessels on rivers and lakes until back in the 60ies – that´s not a new technology, right? How come that they only just “recently” appeared in sailing?”
VPLP | Quentin Lucet: “You are absolutely right: Foils are definitely not a new technology. The foil concept exists for many decades now, but in the past it was mainly used for power boats. On the oceans it came in the multihull world first with all the ORMA-boats which had C-foils. Those couldn’t make the boat fly like today, but were helping to lift out the platform. The first boat coming from VPLP Design drawing board, back in 1983, was a foiling 50-footer trimaran. A multihull as well, as you can see. We had to wait for a real technological jump, on the understanding of the materials as well as the capability to compute calculations to see a real evolution in the foil use. It´s funny, but guys like Eric Tabarly back then were already convinced that the future of sailing was in the foils: And that was back in the Seventies and Eighties! The HYDROPTÈRE-project was motivated by this intuition. Launched in 1994 they had to wait until 2009 to beat the the world record of 51 knots over half a nautical mile. So, we just had to wait for the technology and the material-knowledge to be mature enough to be used in the racing world.”
NO FRILLS SAILING | Lars Reisberg: “Let´s talk IMOCA foils – when have the first ever foils been fitted to an IMOCA and what did these „first generation“ foiling yachts do good – and what not?”
VPLP | Quentin Lucet: “The first foils were fitted on IMOCAs for the Vendée Globe of the year 2016. We had six designs in collaboration with Team Verdier. This edition of the race was driven by an overall rule change: We´ve had considerable doubts that it would be possible to make the new generation boats faster than the previous one. So we tried to add some foils on these boats. I am honest, we weren´t so sure at the time that this would work in heavy offshore conditions. So we left ourself the opportunity to come back to a “conventional” configuration as per the last generation, like MACIF from François Gabart, who won the Vendeé Globe of 2012.”
“When that boat was reaching, for a boat speed of some 20 knots, we had approximately three tons of displacement in the hull. At the same time we´ve got 3 tons of lift in the keel and also 3 tons of lift in the foil. That would give a 3 knots speed gain compared to the non-foiling configuration, as we saw. But this first foil generation was not a good design for upwind conditions, nor was it for going straight downwind. It was more like a “boost” for the reaching mode. But the good thing after the 2016 edition was that we now had no doubt at all that the future of the IMOCA would be in the foiling world! Armel LeCleach won in 74 days, which is still a Vendée Globe-record and Alex Thomson coming in in second place only a few hours behind. Amazing!”
NO FRILLS SAILING | Lars Reisberg: “As I understand correctly, with the advent of foils, it made the design and construction of whole new boats and hulls a prerogative: Why don´t work foils on ex-daggerboard IMOCAS as good?”
VPLP | Quentin Lucet: “Now, that may have been true for the first boats, but it´s different now. With carbon construction we can have a real evolution from the launch of any boat in its original configuration. We now indeed can upgrade an ex-daggerboard boat to a foiling configuration and obtain quite a competitive boat! Of course, this evolution has to be made with a proper structural reinforcement. Because with the foils implemented the boats will be faster with real different behaviour and therefore, we have to take this into account for the hull structural reinforcement. For example, the slamming zone won’t be located in the same areas anymore, we have to reinforce around the keel zone now.”
NO FRILLS SAILING | Lars Reisberg: “How did the foil design evolve over the years? Which majors milestones or learnings, maybe from big races or even major desasters, did it take to arrive at today´s foiling technology?”
VPLP | Quentin Lucet: “Over the past decade, foil development in the IMOCA-fleet has progressed across three distinct generations of boats. The Vendeé Globe 2016-generation marked the debut of foils, which were primarily designed for optimal performance in reaching conditions. Four years later, the Vendeé Globe 2020-generation introduced significantly larger foils which proved highly effective in transatlantic races but struggled in the challenging conditions of the Southern Ocean. Notably, Yannick Bestaven won the Vendée Globe 2020 using a boat from the 2016 generation. Interesting, don´t you think? Following extensive debriefs with skippers and analysis of feedback from the 2020 race, the next stage of foil evolution focused on key improvements: To enable earlier take-off, to enhance seaworthiness in rough sea states and to expand the foils’ versatility for both upwind and downwind performance.”
NO FRILLS SAILING | Lars Reisberg: “What are the major difficulties or obstacles for your as a naval architect to overcome in designing a good foil?”
VPLP | Quentin Lucet: “Well, first I would say that The foil design cannot be isolated from the global architectural consistency. The boat is a complete unity, you cannot separate the foils from it. The foil design needs to take into account the hull design as well, also things like the keel angle and so forth. The design of a foil will generate more or less heel angle at different sailing range: So we have to make sure that the hull as been designed accordingly. An IMOCA has to be seen from a global point of view, and we can’t isolate the foil design.”
NO FRILLS SAILING | Lars Reisberg: “When working on a foil design, let´s say for Jeremy Beyou or any other Vendeé Globe-team, do they come up with special wishes or a briefing to you or do you design the boat (and as such the foils) completely „free“ of individual wishes? Is there even room for individual wishes?”
VPLP | Quentin Lucet: “Yes, definitely! This is true for a boat in general and also for the foil as a detail. We have to put priority on certain conditions of use. We evaluate different candidates on given sailing points and make sure that the skipper always feels comfortable with the evolution we are proposing. To give an example, we can have two design briefings: One that puts forward an early take off for transition mode and the other would prefer to have stability in big rough sea state. This is really linked to the skipper´s experience and feedback.”
NO FRILLS SAILING | Lars Reisberg: “I´ve seen that foils (as the rest of the rigging and structure in an IMOCA) are equipped with sensors. What do these sensors gauge and why is this so important?”
VPLP | Quentin Lucet: “When racing, the forces generated become so strong that they have the power to break parts in an IMOCA. If we don’t monitor these loads, this can happen quite quickly. These sensors and gauges in general are telling the skippers in real time how far away they are from max loads and possible breakage. This is something which is true for the mast, the foils, the hull bottoms … sensors are pretty much everywhere. And accordingly, the skippers have to check the loads constantly to make sure they stay within acceptable ranges.”
NO FRILLS SAILING | Lars Reisberg: “How is a modern IMOCA foil produced?”
VPLP | Quentin Lucet: “Well, a typical IMOCA-foil is composed of approximately 95 per cent of carbon fibres. Its weighs between 230 and 300 kilograms. There are indeed many different technologies to build foils: We are using robots for example to lay the fibres. We also have a lot of hand lamination in a mould as well. It depends.”
NO FRILLS SAILING | Lars Reisberg: “I see … manufacturing secrets. Let´s speak about the future: What do you see there regarding foils in sailing? Will we see more flying boats, even in cruising, or is this something exclusively done for racing? Where is the limit in your opinion?”
VPLP | Quentin Lucet: “There has been significant technology transfer from the world of foiling racing into other sectors, that one is true. The expertise we’ve developed in foil technology can be applied to other sailing classes, of course, particularly for inshore racing. For example, we incorporated foils into the design of the Figaro 3 to improve performance. However, to achieve a meaningful performance boost, a boat must reach speeds of around 20 knots. That is a condition not commonly encountered in everyday cruising, to put it mildly. Additionally, not everyone is ready for the intensity of sailing a fully flying boat or the need for safety gear like helmets during sailing. Foiling technology also has potential applications in powerboats, where it can help reduce drag, leading to energy savings and lower fuel consumption.”
NO FRILLS SAILING | Lars Reisberg: “And last but not least, Quentin: What do you think in terms of the current 10th edition of Vendeé Globe: Is the „fight“ of the old daggerboard-IMOCAS against the foiling boats a real one or just a PR-gag?”
VPLP | Quentin Lucet: “For me the answer is pretty clear: The question whether to use of foils or not for the next generation-boats is a no brainer! There is no such question: As we speak, the first twenty boats in the Vendée Globe 2024 are foilers … So, in my opinion it´s quite simple and safe to say that if you want to have a competitive boat, you have to have foils!”
Thanks so much, Quentin, for that interesting insight! Let´s wait and see how the current edition of the Vendeé Globe will end and how the latest generation foiling IMOCAs have performed!
You might as well find these connect articles interesting:
At Multiplast in Vannes
A walkthrough of Sebastien Simon´s GROUPE DUBREUIL IMOCA. Almost.
Carbon fibers simply don´t like slamming