AMC Introduces New Surface Effect Vessel Design

Specialist aluminum boat builder, Aluminium Marine Consultants (AMC), has added a new surface effect ship (SES) design to its portfolio which is geared towards the crew transfer vessel market and designed by Norway’s Espeland and Skomedal Naval Architects (ESNA).

The new ESNA Tern SES CTV is a next generation high performance crew transfer vessel, offering turbine access in up to 2.5m significant wave height, with a maximum speed above 40 knots and greatly reduced speed loss in high seas.

Rob Stewart, commercial director, AMC, said: “This vessel is unique in the qualities that it offers and we’re very excited to work with ESNA. This new design will enhance the AMC portfolio and help innovate the crew transfer vessel market.”

The vessel’s tern hull consists of two slender catamaran hulls with the area between the hulls closed with flexible reinforced rubber fingers in the bow and an inflated rubber bag in the stern. This allows centrifugal fans blow air into the enclosed space, providing an air cushion that lifts up to 80 percent of the vessel weight.

In fact, the vessel can be lifted up and down approximately two meters, which means it is able to cancel up to the same height of vessel motion in waves. This is especially effective in long waves/swell, where all other vessel types will float and follow the wave surface.

While all SES are lifted by their air cushion, the Tern is lifted relatively higher than other SES designs. This is to increase the performance of the motion damping system and allow operations in higher sea states. While operating at the wind turbines, the air cushion damping system is actively working to reduce wave induced motions.

The remaining 20 percent of the vessel’s weight is supported by side hull buoyancy which allows for high vessel speed because frictional resistance is decreased. 

The Tern is equipped with a computer controlled active motion damping system which reduces vertical motions both at high and low vessel speeds reducing seasickness. 
As the lift fans supply air to the air cushion, the control system actively controls vent valves that either ventilate the air cushion to a low pressure or closes the valves so that the air cushion pressure is increased. 

Aluminium Marine Consultants is one of the U.K.’s leading aluminim boat builders providing innovative and original, bespoke solutions to vessel construction and design. Based at the entrance to the Medina River Cowes in the UK, AMC specializes in the design and construction of aluminum alloy workboats for a wide range of applications, including the offshore crew transfer sector. Established in 2007, it has now built over 45 vessels.