21 January 2016
Article from The Marine Professional
The first of a new generation of large ro-ro/container (con-ro) ships has entered service on a transatlantic route. The first of five built for Atlantic Container Line (ACL), the Atlantic Star can carry 3800 TEU. Whilst the same dimensions as its predecessor, this is more than double the box-carrying capacity. Together with other innovations aimed at improving efficiency, this brings down emissions per container by two-thirds.
The G4 series, designed by the Danish naval architects KNUD E. HANSEN, also has 28,900m2 of ro-ro space and space for 1300 vehicles. The ro-ro ramps are wider and shallower and the ro-ro decks are higher (up to 7.4m) with fewer columns, enabling much easier loading and discharge of oversized cargo. The fleet continues to employ cell-guides on deck, as the line believes this provides added-value to its customers by drastically reducing the risk of containers falling over the side.
The ro-ro spaces are arranged generally at midship area and container bays are be arranged in both ends of the vessel. Most modern con-ro vessels stow containers on deck and lighter ro-ro cargo underdeck. Because of the significant air space that naturally occurs between ro-ro cargo compared to the denser stowage of containers, most of the weight rides high, necessitating significant ballast for stability. Putting the ro-ro cargo midships, and stowing the containers in cells fore and aft results in cargo replacing ballast and more efficient use of vessel space. The accommodation block and navigation bridge are located midship on top of the ro-ro area.
The vessel has a transom stern, high efficiency rudder and single screw fixed pitch propeller directly driven by a slow speed Wärtsila 8RTflex68D engine. The engine room is located aft. There is a pipe duct between the engine room and the bow thruster room. With a service speed of 18kt, the vessels will make an Atlantic crossing in around seven days.
The remaining four G4 vessels are currently under construction at Hudong-Zhonghua Shipbuilding in China and will be delivered to ACL, a subsidiary of Grimaldi, during the first half of this year.
While some have questioned the timing of the new ships coming on-stream in the face of overcapacity in the container segment, the UK-registered Atlantic Star was reportedly ‘deeply laden’ for its inaugural commercial voyage.