Primus was built by Mutzelfeldtwerft under contract to Ferrostaal AG of Essen, with the hull and major steelwork built in Poland. The finished vessel measures 48.87m in length with a beam of 13.80m, a draught of 5.20m and a gross tonnage of 1262gt. Designed by Worldwise Marine, primarily for long-distance towing and anchor-handling, the tug is equipped for berthing, fire fighting and salvage work.

Primus meets the requirements of Germanischer Lloyd +100 A5 E2 deep sea tug boat (area-A4) MC AUT, FiFi 1.

The new tug is powered by two MAK 9M25 main engines producing a total of 6,400kW (8,696 bhp) at 750 rev/min.

Power is transmitted to twin controllable pitch propellers, turning in fixed nozzles, via Reintjes gearboxes. Handling characteristics are enhanced with the addition of twin high performance, flap, rudders and a 400kW LIPS bowthruster. This arrangement gave the completed vessel a bollard pull of 104 tonnes at MCA and a maximum speed of 16.5 knots.

Electrical power is supplied by two 840kVA shaft generators and one 625kVA alternator driven by a Caterpillar 3412 C diesel. The fire fighting system is supplied by two engine driven pumps with a capacity of 1200m 3/hr at 14 bar.

Towing and anchor-handling equipment aboard Primus includes a Hatlapa AH 1.000 electrically driven waterfall winch carrying three steel wire ropes of 70mm diameter; One 1,200m towline, one 800m spare wire and a 300m work wire. The stern roller has a safe working load of 250 tonnes and two 10 tonne tugger winches are provided. Line handling is carried out using Karmoy forks and pins with a rating of 300 tonnes. Salvage equipment includes two portable diesel driven salvage pumps and a 50bhp workboat.

The distinctive bridge is fitted out to the highest standard with navigational equipment that includes two ARPA radars, with ECDIS, and a LIPS DEBEG 4112 Satlog 'Joystick' positioning system. Communications equipment meets the GMDSS Area 4 standard. Fully airconditioned accommodation is provided for a maximum of 18 persons and comprises seven cabins for officers and eight for crew, along with the usual galley, mess, stores and sanitary facilities.

The new order, recently placed with Mutzelfeldtwerft, is for what has been described as two multipurpose vessels designed for long-distance towage and offshore work and believed to be the most powerful tugs to be operated by a German owner.

To be named AHT Magnus and AHT Taurus , they will larger versions of the Primus , with an overall length of 58.5m and beam of 14.8m. A minimum of 180 tonnes bollard pull has been specified requiring main engines rated at 12000kW (16,000 bhp).

The new tugs will be operated under the German flag and are expected to be delivered in August and November of next year.