Cariboni and Wally developed the innovative electro-hydraulic steering system aboard Esense to satisfy two demands associated with the design and construction of the 143-footer megasailer. "The first was providing fast and direct steering for a light-displacement sloop in excess of 100 feet to meet the high maneuverability characteristics of this kind of yacht," explains project manager Davide Legati. "The second was to simplify the connection with the twin helm wheels and control console, which are located quite far forward of the transom."

The standard solution would have been to install cable steering, but this created problems both with regard to the length of the cables involved and the need to install a gearbox to vary the loading on the helm. An additional problem was bypassing the wall of glass where the salon looks onto the stern terrace.

The solution: to borrow the servo-assisted concept commonly found on modern automobiles and adapt it to a boat at sea, which is subject to many more variables than a car on the road. The system consists of a closed circuit with a hydraulic cylinder, which is activated directly by the helm wheels and moves a second rudder cylinder without the need for an intermediate pump. This system, which by itself requires a certain physical effort to steer, is totally independent.

In addition to this "manual" system, there is a second pump-driven cylinder that can increase or decrease the pressure on the rudder and is controlled by dedicated sensors. In this fashion, the helmsman is required to apply constant counter pressure on the wheel as in a typical fixed-cable system.

In addition to these two functions—manual and servo-assisted—there is a third hypersensitive function that controls the hydraulic cylinder via two potentiometers mounted on the helm wheels. This provides very light steering control with limited helm movement. A single complete turn will move the rudder through a full arc from port to starboard. The result is fast, precise control suitable for precision maneuvering when at speed or in harbor.

The last steering element aboard the yacht is the automatic pilot that activates the rudder cylinder via its own hydraulic pump and is suitable for delivery voyages or fixed-route sailing over long distances.

These functions can be activated from the control console in the cockpit, and each one is automatically bypassed by activating another. The result is a simple, efficient and manageable system adapted to the various steering conditions at sea.