Originally, a precursor : Hervé Devaux…
In 1993, Hervé Devaux created HDS and was a forerunner in the introduction of aeronautical computation software to design multihulls. At that point, he participated in the construction of boats for some of the biggest names in sailing. The first of the boats on the list dates back to 1994 and Primagaz, skippered by Laurent Bourgnon. Loïck Peyron’s Fujifilm followed in 1996, then Groupama in 1998 …

« Failure is an option here. If things are not failing, it means you are not innovating enough »
Elon Musk, founder and CEO of SpaceX and Tesla Motors

Surpassing ourselves so that you surpass yourselves and helping you make your dreams a reality. Equally, innovation and setting new targets at Gsea Design, is a belief that spans 3 generations of engineers.

« Creating composite parts, which will make a difference tomorrow, both in the marine environment and in industry. »

Making calculations to ensure our clients the design and fabrication of reliable and innovative composite structures, which perfectly adhere to their needs or ideas, whether they comprise offshore race boats, cruisers or industrial projects.

Our fields of expertise


We intervene before projects so as to bring our expertise into play among architects and other project developers. We offer a comprehensive design from specifications previously drawn up with our clients or a revamp of an existing design ...


The multidisciplinarity of our teams enables us to monitor our projects to a point where we can provide a comprehensive detailed plan of the parts that we design and calculate.

These plans are used directly by yards and optimised to ensure that no modification is necessary during the manufacturing phases.

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We are design engineers specialised in mechanical engineering. Our expertise revolves around carrying out mechanical studies and the calculation of structures using finite element analysis to simulate the behaviour of products and processes. Structural calculation using finite element analysis simulates the behaviour of a part or structure subject to the stresses of its environment in the form of distortions-constraints. ...

Tooling development

We run some of our digital simulations using recognised 2D and 3D CAD and FEA software.

We’ve developed a designated FEA design and optimisation tool (finite element calculations) for any beam pattern and hence masts..

Monitoring of refits

We maintain our expertise in the monitoring of refits thanks to a shared History with the manufacturing sites for projects of international dimension: Europe, USA, NZ, etc...