ASV hulls dramatically improve ship efficiency by riding on air
ESI's Air Supported Vessel is sort of a wedding of the hovercraft and the planing hull. Instead of a smooth V-shape, the bottom has a pair of sharp, blade-like projections in the bow that funnel water into a trough down the middle. On either side of this are a another pair of cavities and at the stern are a pair of pods containing the screws to propel the craft. As the boat moves through the water, high-pressure air is pumped into the port and starboard cavities and this forms a kind of bubble under the hull that lifts as much as 85 percent of the hull's displacement out of the water. There are no rubber skirts needed as in the hovercraft and the cavities are integral with the hull.
This arrangement greatly reduces the wetted area of the hull and reduces hull friction by about 50 percent with increased efficiency of 40 percent once the energy cost of running the air compression system are deducted. It also produces very little wake, so it is ideal for sheltered waterways, such as harbors and canals.
Source: gizmag.comAdded: 7 March 2012