Controllability of high-speed craft

The necessity for high-speed naval vessels with increased capability levels with performance levels in higher sea states is leading to designs with displacements upwards of 2,000 tonnes. One way in which the overall operability in a seaway is being improved is through the incorporation of active ride control systems (RCS) in the design. These ride control systems are also used to control ships at high speeds that would otherwise be statically unstable in such conditions. The paper explains how, through an Office of Naval Research (ONR) project titled Composite High Speed Vessel (CHSV), the controllability of high-speed vessels was investigated. The CHSV incorporated lifting body technology, patented by Navatek, Ltd. This technology features a novel combination of hydrofoils and lifting bodies called the Blended Wing Body (BWB) as described in Hackett et al (2006). The BWB includes an advanced ride control system equipped with a number of actively controlled lift generating devices. An extensive investigation was performed that comprised numerical analysis and physical testing. This paper discusses the results and presents interesting insights, detailing the efficiency of a ride control system for such foil-supported vessels. Finally, disadvantages of the design and operability of these types of craft are discussed.