WIGs (Wing in Ground) are advanced hybrid air cushion crafts and they offer the combination of speed, fuel efficiency, and ride smoothness. WIG rides above the surface like an airplane on a dynamic air cushion that is produced by the vessel's forward motion. The adoption of WIG has been slow due to the complicated technology issues surrounding the vessel; it is a hybrid vehicle that combines marine and aviation theory, wing theory and air cushion theory, aerodynamic and hydrodynamic theory. "WIG Craft and Ekranoplan: Ground Effect Craft Technology" provides a comprehensive overview of the design, development and building of WIG vessels.

Drawing upon years of practical experience and using numerous examples and illustrative applications, Liang Yun, Alan Bliault and Johnny Doo discuss:

• Basic principles of WIG craft technology

• State of the art overview of WIG craft technology in the United States, Russia, Germany, China and Australia

• Material and structural design of WIG craft

• Lift and propulsion systems of WIG craft

WIG Craft and Ekranoplan: Ground Effect Craft Technology will be of interest to naval engineers, aviation engineers, naval architects, and mechanical engineers interested in the development and research of wing in ground (WIG) and high performance marine vehicles.

Zusammenfassung
In the last half-century, high-speed water transportation has developed rapidly. Novel high-performance marine vehicles, such as the air cushion vehicle (ACV), surface effect ship (SES), high-speed monohull craft (MHC), catamaran (CAT), hydrofoil craft (HYC), wave-piercing craft (WPC) and small water area twin hull craft (SWATH) have all developed as concepts, achieving varying degrees of commercial and military success. Prototype ACV and SES have achieved speeds of 100 knots in at calm con- tions; however, the normal cruising speed for commercial operations has remained around 3550 knots. This is partly due to increased drag in an average coastal s- way where such craft operate services and partly due to limitations of the propulsion systems for such craft. Water jets and water propellers face limitations due to c- itation at high speed, for example. SWATH are designed for reduced motions in a seaway, but the hull form is not a low drag form suitable for high-speed operation. So that seems to lead to a problem maintain water contact and either water propulsion systems run out of power or craft motions and speed loss are a problem in higher seastates. The only way to higher speed would appear to be to disconnect completely from the water surface. You, the reader, might respond with a question about racing hydroplanes, which manage speeds of above 200 kph. Yes, true, but the power-to-weight ratio is extremely high on such racing machines and not economic if translated into a useful commercial vessel.

Inhalt
Wings in Ground Effect.- WIG Craft Development.- Longitudinal Force Balance and Trim.- Hovering and Slow-Speed Performance.- Aerodynamics in steady Flight.- Longitudinal and Transverse Stability.- Calm Water Drag and Power.- Seakeeping and Manoeuvrability.- Model Tests and Aero-hydrodynamic Simulation.- Structural Design and Materials.- Power plant and Transmission.- Lift and Propulsion Systems.- Concept Design.