Solving the Puzzle That’s Cousteau’s Turbosail

I was deeply puzzled by how the Cousteau-Pechiney Turbosail worked. The sail, or sails in the case of Jacques-Ives Cousteau’s new research vessel, Alcyone, appeared to be no more than a pair of oversized stovepipes mounted on a sleek, 103-foot hull. Surely, there was something inside the stovepipes, some clever device that rotated, perhaps on some experimental, so-called Japanese sails on a freighter I’d read about, that drives the vessel.

The mystery was solved last Saturday when the Alcyone visited Newport Harbor on her way to San Diego. She was tied up at the Sea Scout Base. The public was permitted to gawk at the unique boat, and gawk they did by the hundreds all day, but they were not allowed aboard. Local dignitaries, including the Huntington Beach City Council, went aboard, however. The Cousteau Society is considering building an ocean center in Huntington Beach. Such a tourist attraction, if it is built there, needs city approval.

Paris will have such an ocean center, designed to show how the world’s fragile living ecological systems work. Ground has been broken for the center.

This bit of information was given me by Timothy W. Knipe, Jr., associate editor of The Cousteau Society’s publications, as we gazed at the Alcyone. Knipe also proved to be a good teacher about the Turbosails.


They really are little more than empty stovepipes. Installed vertically on each of the faces of these giant tubes is a door, or shutter-flap, that runs the height of the Turbosail unit. These shutter-flaps can be opened and closed, while the stovepipe, or cylinder, is rotated hydraulically, into the direction of the wind. Thus, very simply, the boat is sailed.

The system operates on the same principle as a conventional sail, yet, according to Knipes, with heightened efficiency. This result is achieved through combining the orientation capabilities of a sail with the aerodynamic design of an airplane wing.

An airplane takes off through a decrease in air pressure above its wings and an increase in air pressure below them. This results in an acceleration of the air currents above the wings, while the currents below them are slowed down.

The wind circulates around the Turbosail cylinder in much the same way, only it’s vertical, and the ship is driven forward, instead of upward. With the Turbosails alone, the Alcyone can make 5 knots in a 15-knot wind. Her best speed has been 9 knots in a 20-knot or more wind. She functions best on broad reaches.


Alcyone is equipped with twin diesel engines which, operated with her Turbosails, give her a 40% fuel saving cost over running with her engines alone. Both the Turbosail cylinder and the flap are oriented automatically by a shipboard computer that monitors the wind direction. The computer also adjusts the amount of diesel power required in addition to the Turbosail units to maintain a constant cruising speed. At the top of the empty cylinder is a fan that sucks air through perforated lateral vents, causing a strong deflection of the air current.

I believe this propulsion system will be adopted by merchant and fishing vessels within the next few years, owing to its potential fuel saving and its safety and simplicity of operation.