Turbosail…

For millennia, sailors have lived at the border between two capricious fluids, water and air. To try to tame the power of these elements, the Cousteau team developed the Turbosail.

In 1980, Captain Cousteau dreamed of creating a ship with a modern engine that would be powered, at least in part, by the wind, a clean, free, renewable energy source. The idea of using a hollow, rotating metal cylinder for propulsion had been tried and discarded decades before Cousteau and a team of engineers decided to revive and improve on it. Cousteau and his associates, Professor Lucien Malavard and Dr. Bertrand Charrier, used a fixed cylinder that looked like a smokestack and functioned like an airplane wing. A movable shutter and system of fan-drawn aspiration improved the efficiency of this new sail. Small-scale models tested in a wind tunnel functioned perfectly, and the Turbosail was born.

When compared to the thrust coefficient of the best sails ever built (Marconi or square types, i.e. ships of the American Cup or the Japanese wind propulsion system) that of the Turbosail is 3.5 to 4 times superior and gives the system a unique advantage for the economical propulsion of ships.

The invention was first tried on a catamaran christened Moulin à Vent (Windmill). Cousteau and his colleagues validated the system by sailing from Tangier to New York. The crossing was nearly complete when, not far from the American shore, they ran into winds of more than 50 knots. The soldering that held the Turbosail in place gave way and the prototype fell into the sea.

Captain Cousteau's experience was turned to good use in designing a new vessel. Working with naval engineers, he designed an innovative hull of aluminum, both lightweight and strong. The catamaran-like stern gave it stability. The monohull forward would split the swells better. Two Turbosails rose from her deck and two diesel engines provided the necessary complement to the wind. The ship was named Alcyone (linked to About us/Vessels/Alcyone), the daughter of the wind.

Alcyone is blessed with the most modern technology; computers optimize the functioning of Turbosails and engines. To maintain a constant speed, the engines take over automatically when the wind dies down, then they stop completely when the wind is strong and from the right direction. A crew of five is all it takes to maintain the ship but, theoretically, with all her control systems, she could sail without a crew.

Turbosail