VTMD supplies ride control system for fast patrol boats

Leading ride control specialist VT Maritime Dynamics (VTMD), part of the UK support services and shipbuilding company VT Group, has won the contract to supply the stabilisation systems for the advanced Skjold-Class fast patrol boats being built for the Royal Norwegian Navy.

The US-based company supplied and fitted the ride control system (RCS), including vent valves, stern boot fans and hydraulic actuation mechanisms, for the first-of-class vessel that spent four years undergoing evaluation. Following the success of this initial craft, a further five Skjold-Class surface effect ships (SES) will be built by Umoe Mandal in Norway.

They will all be fitted with VTMD ride control and stern fan systems, while the initial vessel will be refitted extensively. The 47 metre boats are built for high speed and manoeuvrability, with a maximum speed of more than 54knots.

Main propulsion is by water jet driven gas turbine engines and the ships? low draft means they will be able to operate effectively in shallow coastal waters. They are also designed for stealth and will have a comprehensive weapons fit.

Surface effect ships operate on an air cushion that carries the main part of the vessel?s weight. Because of the high-speed requirement, the Skjold-Class will carry no underwater appendages as most ride control systems would include. The solution is an RCS that monitors and regulates the pressure of the air cushion by controlling vent valves, which reduce accelerations and mitigate crew fatigue.

The stern fan system controls the stern seal pressure. During high speed operation incorrect pressure in the stern seal can result in instability that can decrease vessel performance.