PERFORMANCE
The performance advantages of hydrofoils are significant and have been proven on hundreds of watercraft vessels. It is known from a large body of evidence that hydrofoil-supported catamarans have softer riding characteristics than equivalent catamarans or deep-V monohulls. The available test data indicates that pitch, heave, and vertical accelerations are reduced by 50% at the center of gravity and further aft; the hydrofoils counter the motion of the hull. When the bow strikes an oncoming wave, the hull starts to rise, changing the angle to the hydrofoil and in turn reducing the lift. The hulls then carry more load, allowing them to pierce through the wave rather than following the wave slope exactly, as a lightly loaded hull does. Conversely, if the hulls heave downward into a trough, the foil lift increases, helping the hull not to slam. Pitch is improved in a similar way but mainly due to the effect of the rear foils.
In short choppy seas the ride is extremely smooth, with the hydrofoils allowing the vessel to run on the crests. In long waves, hydrofoil-supported catamarans tend to become airborne more easily, but this tends to be maintained with constant trim angle if the hydrofoils are set up correctly, and does not create excessive vertical accelerations. The reentry is smooth and drama free as the hydrofoils help disperse impact.
Another advantage is that at planing speeds a drop in resistance of up to 50% is possible, which equates to significantly higher speeds as well as lower powering requirements. Lower power normally results in a 30% reduction in fuel consumption at planing speeds.
The benefits extend to maneuvering: As the hull is partially lifted out of the water when changing course, its lateral area is reduced, allowing tighter turning circles than conventional catamarans and monohulls can execute. Unlike regular catamarans, HYFOILs are designed to lean into a turn much like monohulls. The foils do not impair handling or create directional instability/broaching problems. Tight turns can be performed in waves without any form of instability.
In short choppy seas the ride is extremely smooth, with the hydrofoils allowing the vessel to run on the crests. In long waves, hydrofoil-supported catamarans tend to become airborne more easily, but this tends to be maintained with constant trim angle if the hydrofoils are set up correctly, and does not create excessive vertical accelerations. The reentry is smooth and drama free as the hydrofoils help disperse impact.
Another advantage is that at planing speeds a drop in resistance of up to 50% is possible, which equates to significantly higher speeds as well as lower powering requirements. Lower power normally results in a 30% reduction in fuel consumption at planing speeds.
The benefits extend to maneuvering: As the hull is partially lifted out of the water when changing course, its lateral area is reduced, allowing tighter turning circles than conventional catamarans and monohulls can execute. Unlike regular catamarans, HYFOILs are designed to lean into a turn much like monohulls. The foils do not impair handling or create directional instability/broaching problems. Tight turns can be performed in waves without any form of instability.