SWATH design provides a very stable and safe working environment that is extremely attractive for workboats. Compared to a monohull, a SWATH exposes only a minimum of the ship to the lifting forces of the waves. The ship’s pitch and roll is significantly reduced resulting in a smoother ride in rough water.

A SWATH ship consists of two long, skinny torpedo-shaped hulls submerged beneath the water’s surface. Connected by thin struts to upper hulls, these submerged hulls support an elevated, above-water platform. Since the submerged hulls do not follow surface wave motion and the struts supporting the elevated deck have a very small area exposed to the water, the ship’s cross section at sea surface level is sharply reduced. The result is a stable platform even in rough seas. Passenger and crew discomfort is significantly decreased. The ride is smooth even in sea states as high as 5 and 6, allowing passengers to enjoy a pleasant ride. Crews can effectively perform even complex tasks such as launch, recovery, tow operations, research, surveys, and tracking.

In addition to excellent seakeeping the other key attribute of a SWATH design is its wide beam, which provides much greater deck space than a monohull with similar displacement. This feature makes SWATH well suited to support a variety of equipment on deck. It is an ideal platform for all types of commercial and government applications that demand stability and maximized deck space.

SLICE

Lockheed Martin engineers working with the Office of Naval Research have taken the SWATH concept one step further by converting the twin-hull design of a SWATH into an innovative four-hull SLICE™.

The patented Lockheed Martin SLICE™ hull breaks the two long submerged hulls of a SWATH into a fore and aft pod, each with larger diameters but smaller lengths. In addition, the fore and aft pods of the SLICE™ design are offset to minimize their wave-making interaction. The result is a hull with the same friction drag as a conventional SWATH, but much lower wave drag and much greater speed.

Both the SWATH and the SLICE™ design can be configured into a size and shape to fit a variety of commercial and government requirements and both technologies are proven. A SLICE™ technology demonstrator has been in operation for several years and a Lockheed Martin-designed SWATH oceanographic research ship is entering service in 2002 at the University of Hawaii.