As shown in the graphic, when a conventional ship encounters a wave, one half of the hull is no longer supported by the buoyancy of the water. Conversely, the other half incurs additional buoyancy. The net result is a roll of the ship which is repeated hundreds of thousands of times during a typical voyage.

A SWATH, however, presents a minimal cross sectional area at the surface of the vessel's waterline. As a wave passes by, the relative change in buoyancy on either side of the vessel is insignificant compared to the mass and stabilizing inertia of the vessel. A SWATH will heave, pitch and roll at a dead stop (or zero forward velocity) seven times less than a conventional vessel. Also, the effect of active stabilizer fins is much more pronounced on a SWATH vessel resulting in virtually no heave, pitch or roll motion underway.

Scuba divers and snorkelers easily and inherently understand the physics of the SWATH vessel because they experience the phenomenon every time they go into the ocean. While they are at the surface they bob up and down with the waves but as soon as they descend below the surface everything calms down. A frequent mantra for seasick divers on the way to the dive site is to just get in the water and start the dive and they will instantly start to feel better.

Another benefit of the SWATH design is superior interior and cabin arrangements, owing to the geometrically convenient shape of the vessel's accommodation decks. The SWATH design also lends itself well to completely isolating engine room noise and vibration from the inhabited spaces. Additional benefits include an extended cruising range due to the abundant fuel capacity derived from ballasting requirements and the ability to sustain cruising speed in rough seas.