In the footsteps of the Hydroptère

July 9th, 2020

SP80 being set up by engineers and students from the Swiss Federal Institute of Technology in Lausanne (EPFL), was not a chance happening. Back before our venture was even an idea, back when our team members considered themselves sailing novices at best, we were witness to the phenomenon called the Hydroptère; a boat developed in collaboration with the very same school, that reached shattering speeds. Ten years later, the trace left by the Hydroptère is still present among EPFL’s professors and laboratories. We hope to make the best of their expertise to make SP80 the fastest sailing boat in the world by 2022!

Imagined by Eric Tabarly and then developed by Alain Thébault, The Hydroptère is a hydrofoil trimaran, in other words a boat that can rise above the water. In 2006, thanks to the intervention of the Lombard family, the EPFL was welcomed on board the project, a collaboration that will take the boat to the world sailing speed record in 2009. – © Guilain Grenier

September 4, 2009. The Hydroptère becomes the fastest sailing boat in the world (95 km/h average speed over 500m) but also the first to pass the whopping 100 km/h mark. Pushing the limits of technology and physics requires a deep pool of innovation, knowledge and infrastructure, which EPFL was capable of providing. Based on previous experience with the Swiss Alinghi team in the America’s Cup, EPFL was aware of the positive impact it could have on the project led by the French sailor Alain Thébault. “Collaborations with Alinghi and the Hydroptère have been high points in the history of the school, generating a great deal of innovation, research and challenges,” says Pascal Vuilliomenet, project manager. “SP80 produces the same dynamic, the difference being that this project was initiated by EPFL students and graduate engineers, which we are very happy about. Many students capitalize on this opportunity to perfect their knowledge, and the laboratories remain open to innovative ideas that could emerge from this new generation.”

Of the five laboratories involved at the time of Hydroptère, three have already made resources and knowledge available for SP80, a valuable support in the quest for the record. Véronique Michaud is the director of the composites laboratory as well as the project’s academic leader: “SP80 is a magnificent adventure, just as demanding as the Hydroptère was. I am delighted to be able to guide them in their academic and technical choices. The LPAC is a wealth of knowledge on composite materials, and our guidance for SP80 concerns carbon fibers in particular, which are essential in high-performance boats. With counsel from LPAC, they have the means necessary to seek an optimal design within the structural limitations imposed by the pilot’s safety.”

When it comes to hydrodynamics, no effort was spared, since EPFL has a unique infrastructure: a cavitation tunnel that can accelerate the water up to 180 km/hour. Testing submerged profiles at these speeds provides valuable information on their behavior and performance, whereas numerical simulations can still be inconclusive. Although the physics technicalities of SP80 and the Hydroptère differ somewhat, Mohammed Farhat, infrastructure manager and member of the Laboratory for Hydraulic Machines (LMH) notes: “The Hydroptère was a fantastic experience as a researcher, and it pushed us to reinvent ourselves. SP80 has the same effect on me! This youthfulness also means they sometimes stray from the well-worn paths walked by people with more experience, but occasionally, they will propose a marvelous idea that a seasoned engineer might miss. Of course, it doesn’t always work in this way, but the results we have obtained in this short time are very encouraging and are the product of a scientific approach that is successfully being carried out.”
These experimental results are then used to feed and validate the numerical simulations developed in the Computer Vision Laboratory (CVLAB), the last laboratory to have been invested in the Hydroptère and SP80.

Charles de Sarnez working on numerical simulations on the SP80 hydrofoils with the Computer Vision Laboratory (CVLAB).

At the crossroads of all these entities is the academic coordinator, Robin Amacher, a naval architect who was a member of the design team of the Hydroptère at the time of the record: “While the wind is the means we will use to propel the boat, this project is above all fueled by passion and dedication. This was already true for the Hydroptère, and it is still true for SP80. Seeing these hyper-motivated young people embark on an enterprise like this takes me back. They’ve got a lot of nerve, yes, but they also have what it takes to achieve their goal, including a solid scientific background and already quite a bit of practice, which they acquired working on interdisciplinary projects like Hydrocontest. My goal is to help them by liaising with EPFL, and by offering guidance that comes with my experience. If I can prevent them from repeating mistakes that have already been made, I can save them a lot of time.”

What about the students in all this? “The Hydroptère calls upon everything I love: the search for speed and innovation,” explains Benoit Gaudiot, co-founder of the SP80 project (on the picture), “In 2009, when they broke the 500m world sailing speed record, I was kiting in Hyères with my parents. I was 12 years old and was part of the French speed kite team. So I lived for speed at the time, and seeing such this craft pulverise what I believed was possible made me dream. Today, with SP80, the dream is not so far away!” The Hydroptère has done more than just beat the world sailing speed record, it has inspired a whole generation to follow in its footsteps: SP80 is hot on its trail…

Aurore Kerr, head of communication

Picture in header: © Guilain Grenier