Measuring 30.8m in length overall, the tugs will have a beam of 11.14m and 3.88m draft.

Below the waterline, the tugs will be fitted with a large 'escort' skeg forward to provide effective indirect towing capability and to enhance course stability when running astern. The forward end of the skeg has been fitted with an ice-stop, designed to prevent the hull riding-up onto the ice.

Two ice-knives will be installed beneath the stern to divert large pieces of ice away from the propellers.

Each tug will be powered by a pair of Caterpillar 3516BHD diesels, developing a total of 5000bhp while running at 1,600rev/min. Two Rolls-Royce Aquamaster US255 propulsion units with controllable pitch propellers will be installed, providing a bollard pull of about 60 tonnes and a free running speed of about 12 knots. A Kamewa 45TV bow thruster of 150kW will also be fitted and auxiliary power is provided by two Caterpillar C9 generating sets developing 165kW each.

For shiphandling operations an electrically powered 150 tonne Ridderinkhof single drum towing winch, capable of accepting 120 feet of 82mm Spectra towline, will be mounted on the raised foredeck. A second frequencycontrolled electric Ridderinkhof winch of a similar type, located aft for towing and anchor-handling, will be equipped with spooling gear and carry 762m of 51mm diameter steel wire towline. The latter will operate inconjunction with a set of 200mm tow-pins, a Ridderinkhof tugger winch/ capstan, a 75 tonne Washington Chain tow-hook and a stern roller.

Two remote-controlled fire fighting water-foam monitors supplied by Skum will be fitted above the aft end of the wheelhouse and each have a discharge rate of 1,200m 3/hr. The monitors and self protection spray system are supplied by a dedicated pump of 2,700m 3/h capacity, driven from the front end of the port main engine.

Comfortable accommodation for six person will be provided, all in single cabins and noise levels will comply with the stringent requirements of the Danish Maritime Authorities.

In the meantime Irving are to hold a naming ceremony on the 10th of June for the azimuthing tractor tug Stevens Arctic ( Towlines - December 2004), sister to the Stevens Ocean built in Canada in 2003. Both of these tugs and the pair of ASDs currently under construction are to be employed on the 'spot market' in the offshore oil/gas industry.