Sanmar Shipyards in Turkey is in the process of shipping a Robert Allan Limited designed Rascal Class ASD tugboat to Port Otago Limited (POL) in New Zealand. The new tugboat is called Arihi, the name having been chosen in consultation with the local Rununga (Maori council). The boat measures 18m long, has a bollard pull of 30 tonnes and was completed in less than five months from date of order.

The new boat will be primarily used by POL in assisting in channel dredging, a task that began in 2015. The aim to have a maintained channel depth of 14m and this work is being undertaken using the Port Otago owned and operated dredge New Era and a 750m3 split hopper barge. In addition to barge manoeuvring, Arihi will be available for ship assist duties and possible external charter opportunities. To accommodate these wide ranging duties, the vessel is fitted with a push bow and special side and aft fendering.

The RAscal 1800 Class of ASD tug is the outcome of high level cooperation between both the operational and construction teams of Sanmar AS and the designers at Robert Allan Ltd. The end result is an agile omni-directional vessel measuring a compact 18.7m x 9.2m with a draft of 3.7m. Regardless of size, it packs a hefty 30 tonnes BP and can maintain a speed of 12 knots.

These performance figures are the product of a pair of Caterpillar C32 main engines, each developing 970kW at 1800 rev/min driving stern-mounted Veth VZ-900 azimuth drives with carbon composite shafts turning 1700mm dia propellers inside high efficiency nozzles with stainless steel inner surfaces. Auxiliary generator sets are also by Caterpillar – a pair of 86ekW C4.4s. Deck machinery items include a forward DMT towing winch and a Data towing hook swung from the aft staple.

The first two sister vessels of this design have proven themselves in extensive operation within Sanmar’s own hardworking fleet.

The vessel will be delivered to Port Otago on a heavy lift vessel in June.