SeaFrame ? the flexible cat

Incat?s new 112-metre SeaFrame under construction at Hobart promises a revolutionary framework for shipbuilding, lower production costs, and significant through life savings for both commercial and military operators. Being built for the account of Incat USA as hull number 64, the final accommodation configuration has not yet been decided. Delivery is slated for 2004.

Design work is well under way and metal cutting is about to begin on Evolution One12 ? a SeaFrame designed ship which represents a departure from the shipbuilding industry?s replication of an aircraft layout. According to Incat, the SeaFrame will cut construction costs in Australia by as much as 50% and these savings could be much higher when compared to a typical US military contractor.

Incat chairman Robert Clifford said commercial operators could expect significant through life savings because the modular concept of the sea frame allowed for the module to be transferred to another ship during refits. He also claims that Evolution One12 would be the largest diesel-powered catamaran in the world and would also offer superior transport efficiency. He declined The Motor Ship?s request for more detailed information about fuel efficiencies, indicating that further information would be revealed in the next few months.

Evolution One12 will draw 36MW of power from four 20RK280 MAN B&W engines to achieve speeds ranging from a heavy load economy speed of 20 knots to 50 knots light ship. Each of the 20-cylinder medium speed diesel engines is rated for continuous operation at 9,000 kW at 1,000 rpm for this application and will drive a water jet. A new wider trim tab configuration will minimise the time the optional forward T-foil is required, thereby bringing further fuel and maintenance economies to the operator.

Evolution One12 is the design brainchild of the Hobart-based company Revolution Design, an independent firm made up of former Incat designers who lost their jobs when a receiver was appointed to Incat in March 2002. The SeaFrame design allows for Evolution One12 to be fitted out for a wide range of operational applications either as a pure passenger ship, commercial cargo carrier, ropax, or various military configurations.

The principal particulars for the basic SeaFrame Evolution One12 is an overall length of 112.63m, hull length of 105.60m, a moulded beam of 30.20m, a draught of 3.30m at 2,350t displacement, a deadweight of 1,500 tonnes and a vehicle deck height of 6.30m. The basic One12 design offers an operational deadweight of 1,000t and deadweight of up to 1,650t at reduced operating conditions. With an increased draught of 3.80m, the vessel?s displacement will increase to 3,000 tonnes.

Commercial operators will be able to fit the vessel with luxurious, yet practical, accommodation for 1,200 or more people. Alternatively, SeaFrame can be completed as a pure Roro dedicated for freight operators, or as a car carrier for trade vehicles.

A Ro-1000 Pax version will give operators a vehicle deck of 3,528m2, and a passenger deck of 1,823 m2 with a 1,000-passenger capability. This version will have an operational deadweight of 865t and overload deadweight of 1,515t. The Ro-700 Pax type will offer a vehicle deck area of 3,528m2 and a passenger deck area of 1,248m2 with a capacity for 700 passengers. In this configuration, the vessel will have an operational deadweight of 926t and overload deadweight of 1,576t. The cargo deck, or mission deck, of the Evolution One12 SeaFrame provides 589 truck lane metres plus space for 50 cars or 312 cars when operated in the full passenger mode. Optional mezzanine decks will give commercial operators even greater car capacity.

The design also has the potential to offer increased vehicle deck headroom of 6.30m and centre lanes allowing the stowage of Mafi trailers. The 30.20m beam enables heavy road vehicles to turn in the bow for quick disembarkation over stern ramps and the extra wide beam also serves to increase passenger comfort by reducing transverse accelerations in the main cabin area.

The Military SeaFrame Air Support offers a 1,225 m2 mission deck area, a 2,340m2 accommodation deck area, a 2,045m2 flight deck and accommodation for 350 troops and 121 crew. This Air Support version will have an operational deadweight of 650t and a deadweight overload of 1,300t.

Other configurations comprise a SeaFrame Multi Mission and SeaFrame troop carrier. The former gives a mission deck area of 2,961m2, a utility deck area of 1,425 m2, will carry 345 troops, provide berthing for 20 troops and crew berthing for 30. Its operational deadweight will be 838t and the deadweight overload 1,488t.

In regard to the SeaFrame troop carrier, this offers a mission deck area of 2,961m2, a utility deck area of 2,060m2, can carry 730 troops, provide troop berthing for 20 and crew berthing for 30 people. Operational deadweight of 825t is envisaged and deadweight of 1,475t is available at reduced operating conditions.

The range of configurations on offer for the military sector also includes the ?littoral combat vessel?, mine counter measure, UAV /STOL capacity, theatre support, helicopter operations and troop transport. Coast Guard operators around the world can have SeaFrame adapted for surveillance and homeland defence missions.

Clifford said that the all-aluminium vessels would be designed to handle any military load or situation and would not suffer any greater restriction than a conventional destroyer. He also said there was almost no known military technology that could not be handled by the SeaFrame. It would accommodate all military vehicles, tanks, mobile weapons, hospital units, command centres and aircraft.

The SeaFrame will undoubtedly help Incat?s ability to promote the wave-piercing catamaran (WPC) platform while providing operators with an opportunity to configure the superstructure of the craft for their individual requirements.

Another feature of Evolution One12 will be the refined centre bow which will provide more lift in the initial stages of wave encounter. This refinement is based on 15 years of continual development to provide more lift in the initial stages of wave encounter. In the recent 98m Incat range the arch between the centre bow and the wave piercing hulls was modified to obtain more freeboard and have less flat surface. This increased the above water clearance by 26% when compared with the 96m craft. In the Evolution One12, the design has been refined further to increase the arch freeboard by 68% over

the 96m wave-piercing

catamarans.