The modern hulls are more and more balanced in heeling. They are too more and more wide in the stern what allows to put them out of the true.
It leads quite naturally to the twin – rudders.
Better control as reaching as tacking
Is positioned every rudder around one heeling average from 13 to 15¨ in the middle of the streamlines. In these conditions, the rudder to leeward is perfectly fed in the middle of the drainage. It becomes vertical, its shovel is always immersed, there is so less ventilation and unhooking of the profile.
As a consequence, well positioned in the drainage, its efficiency and its preciseness increase so that its size can be decreased while keeping the control of the boat much more late. Reaching in great speed, this greater directional control allows navigating much more efficiently in more difficult conditions.
With two smaller rudders, the efforts decrease much and the safety increases.
The rudders are much smaller and briefer so double less loaded in equal control. The effort is less important on the rudder stocks, the moment of the flexion which determines the resistance of the rudder stock is the product of the distance of the stress and of this stress (determined by the surface and the speed): distance and surface decrease.
Twin – rudders, additionally, free the centre of the transom in the case of retractable rudders on the transom and allow facilitating the access of it: boarding, bathing, fishing, even for outboard engine depending on the cases.
From the mini – transat to the 60 feet, our racing boats which are equipped with it won everything. Bi – rudders make them even easier to lead solo; and what is more comparable with a cruising boat than the boats the only rating rule of which is: one man, the wind, the sea.