During a trial period, Marcel Gianoli implemented a new process on Éric Tabarly’s Pen Duick that enhanced its performance.
It used a very lightweight wind vane balanced by a counterweight and mounted on a rotating stand. The wind vane revolved around a vertical axis, which enabled it to set the boat’s course in relation to the wind. Normally in a vertical position, any change in the wind direction would push against one of the sides of the vane and force it down.
While carrying out tests on Éric Tabarly’s Pen-Duick II during the Observer Single-handed Trans-Atlantic Race of 1964, Marcel Gianoli implemented a system using an inclined axis. The vane rotated around an axis that was slightly inclined at an angle well above that of the change in wind direction. The system was therefore much more efficient than a traditional wind vane with a vertical axis.
In 1964, Éric Tabarly won the transatlantic race with the Pen Duick II.
Éric Tabarly on Pen Duick II (equipped with the windvane gear system developed by Marcel Gianoli the ECA Group founder) after winning the OSTAR. June 18, 1964.