The Unlimited is the 20th Incat Crowther design built by Richardson Devine Marine. A 78.7 ft catamaran work boat, the Unlimited was built for Offshore Unlimited, who provide comprehensive offshore services, including oil rig supply, survey ship re-supply and chase boat services, around Australia.
The platform is based on the successful Incat Crowther catamaran hull form which has been heavily utilized in ferries, motor yachts and work boats around the world over the last decade. The platform features a highly efficient hull shape which leads to lower power requirements, lower fuel consumption and longer range capabilities. The hull has a wide beam, allowing easy engine room access for maintenance and repair, spacious crew quarters, high load carrying capability and possesses excellent seakeeping characteristics.
During the vessel development stage Incat Crowther worked with the customer and the shipyard to customize the standard platform to suit the clients’ specific requirements for the operation. These include a multipurpose deck crane, incorporating a wireless control system for launching the vessels tender, as well as general duties on the large open aft deck which includes a 4 ft square moonpool for underwater operations. In addition the aft deck is fitted with securing points for a standard 20 ft container and a stern platform for water access. A unique feature for a lightweight aluminium high speed catamaran is the addition of a towing hook enabling the vessel to undertake lightweight tug duties, with a bollard pull of 15 tonnes. The vessel has also been fitted with bow thrusters in both hulls for operating within close quarters of other vessels or structures.
The vessel maintains standard workboat characteristics including the main cabin facilities forward. The main deck houses two crew cabins, a galley, mess area, bathroom facility and lounge. The fitout standard is very high with the shipyard utilizing its high speed ferry standards for construction with a very smart, modern appearance. In the hulls are crew quarters for a further 10 crew and a large store room located in the port hull. A spacious wheelhouse is positioned on the upper deck and commands all round visibility for the operational crew. Workspaces are also available for visiting engineers with all the latest communication outlets available.
Powered by twin Caterpillar C32’s each producing 1,400hp the vessel will have a service speed of 26 knots. Sea trials were successfully conducted in very rough conditions in Australia’s Bass Strait.
The Unlimited has an extended range of 1,875 nm at 22 knots thanks largely to two 12,500 litre fuel tanks. This will allow the operator the range to reposition the vessel far more efficiently than with multiple refueling.
This vessel is intended to operate along the northern coastline of Australia particularly on the North West Shelf oil and gas fields.
Design Type Catamaran Work Boat
Survey Marine and Safety Tasmania (USL 2A)
Construction material Marine Grade Aluminium
Length o.a. 78.7 ft
Beam o.a. 26.2 ft
Draft (approx) 7.4 ft
Overnight: 12 Crew
Passenger Capacity: 38
Fuel capacity 2 x 12,500 litres
Fresh water capacity 1 x 1,500 litres
Deadweight 55 tonnes
Engines 2 x Caterpillar C32
Power 2 x 1,400 bhp @ 2300 rpm
Gearboxes 2 x Twin Disc MGX6599
Propulsion system 2 x Fixed Pitch Propellers
Service Speed 26 knots
Max Speed 29 knots