Feature:There's Something About Mary

Queen Mary 2 will not only be the largest, tallest and fastest passenger ship of its type in the world; it will also revive the august tradition of the transatlantic liner and take the design of such vessels several steps further into the future

The long and illustrious tradition of glamour associated with transatlantic liners is set to continue when Queen Mary 2, owned by Cunard and classed by Lloyd's Register, leaves the port of Southampton for Fort Lauderdale on its maiden voyage in January 2004. After this first voyage, Queen Mary 2 will sail the traditional transatlantic liner route from Southampton to New York City for which it was specifically designed, although the ship will, over its lifetime, play a dual role as both liner and cruise vessel. Upon completion in December 2003, it will be the largest, tallest and fastest passenger vessel of its type yet built in the world, at a height of 236 ft. (72 m), a beam of 134.5 ft. (41 m) and a length overall of 1,132 ft. (345 m). "From the beginning, Carnival Corporation [Cunard's parent company] made it clear that it wanted a vessel that would be able to sail the cruise trades, as well as operate in the original liner trade from the UK to New York City," says John Rugg, Senior Vice-President and Cruise Business Manager for Lloyd's Register. "This meant that Queen Mary 2 would have to be able to operate to a strict timetable in all weathers and that it would need to have a robust structure that could deliver that reliability of operation."

The vessel's hull structure is unique in several ways that are a direct result of both the ship's size and its intended route. Queen Mary 2 has a long, slender bow to enable it to cut through the waves of the North Atlantic, and its superstructure of seven decks is set back to prevent damage from greenwater. For passenger comfort, the vessel will be fitted with two sets of 'active fin' stabilisers to reduce rolling. In addition, to give the ship's structure greater strength and support, it is being built as a longitudinally framed ship structure, in which the longitudinal members traverse the length of the ship, rather than as a traditional transversely framed ship structure.

"Queen Mary 2 is an extremely strong ship," says Warwick Malinowski, Lloyd's Register Senior Ship Surveyor, who spent five weeks on-site at the Alstom Chantiers de l'Atlantique's Saint-Nazaire yard, where the ship is being built. "The plates in the bow are completely different from those on a normal cruise ship. The structure may look the same as that of any passenger ship from the outside, but internally and with respect to the thicknesses of the plates, it is completely different."

A further unique feature of the vessel is the inclusion of three open public spaces, with minimal obstruction by pillars or other supporting structures. To facilitate these open spaces, which include a theatre, the designers had to create suspension structures supported by longitudinal bulkheads running over them.

Queen Mary 2 will have a total of 1,310 staterooms, three-quarters of which will have private balconies. Over 90 of these will be suites, including six penthouses and five 1,650 sq. ft. duplex apartments. Other features will include a 1,300-seat three deck-high restaurant, five swimming pools, an art gallery and various entertainment venues. Queen Mary 2's lower bed passenger capacity will be 2,620.

Crosshead Power and Propulsion

Power will be generated by four Wärtsilä 16V46C diesel engines, each rated at 16.8 MW, and two General Electric LM2500 gas turbines, generating 25 MW each. The power for all shipboard systems — propulsion, engineering, lighting and other systems — will be routed through two main switchboards.

The General Electric gas turbines were chosen specifically for their ability to provide the vessel with the extra power it would need to reach and maintain a speed of over 29 knots without impacting the ship's internal volume.

Like most modern passenger vessels, Queen Mary 2 is practically a 'floating power station', says Lloyd's Register Senior Surveyor John Baghurst. Running at 90 percent of the plant's full power, the vessel can attain a speed of over 29 knots in Force 2 sea conditions.

Propulsion will be provided by four pods, two fixed and two azimuthing, with the steering function being provided by the two steerable pods. The vessel will not have a separate rudder.

Queen Mary 2 will also have three bow thrusters equipped with hydraulically operated closing doors. When the ship is at full speed, the doors will be closed, further streamlining the ship's hull and allowing reduced resistance. "To my knowledge," says Malinowski, "this is the first such vessel to have four pods and closing doors for its bow thrusters. These features are yet another example of the innovation brought to bear on this unique vessel."

As an added assurance of the reliability of the vessel's propulsion system, Cunard has selected Lloyd's Register's propulsion and steering machinery redundancy (PSMR) class notation. In order to achieve the notation, the ship must be able to retain a minimum of 50 percent of its propulsive power and maintain steering capability at a speed of not less than seven knots in the event of a machinery failure. In addition, a failure mode and effects analysis (FMEA) must be carried out on all propulsion systems, electrical power supplies, essential services, control systems and steering arrangements. Queen Mary 2 will have a single engine room, but in the event of flooding or other damage, emergency power would activate instantly, while the General Electric gas turbines located on Deck 14 behind the funnel would come on line in seven minutes or less to provide full back-up power.

Crosshead All for One

In addition to participating in the design of the vessel and overseeing its construction, Lloyd's Register has also been closely involved in the statutory work related to Queen Mary 2, acting as the single point of contact for Alstom Chantiers de l'Atlantique.

"As well as helping with the structural specifications, we looked at the ship's safety aspects," says Rugg. "We knew that Queen Mary 2 would fly the British flag and that statutory certification would be the responsibility of the U.K.'s Maritime and Coastguard Agency [MCA]. To ensure efficiency and the best service possible, we formed an agreement with MCA, which empowers us to work in conjunction with the agency to oversee safety matters such as watertight integrity, watertight subdivision, damage stability of the ship and life-saving arrangements. It is an unusual arrangement, but because of the size and the complexity of the ship it was felt to be a necessary step to facilitate a more efficient plan approval and survey regime."

In Malinowski's experience, the shipyard has also been extremely efficient. He points out that Alstom Chantiers de l'Atlantique has a long history of involvement with famous passenger vessels, including Normandie and France. "The yard is well organized, particularly the internal logistics system. If you think of a ship under construction as a complex number of parcels, which are spread out around the yard in various stages of completion, then you can imagine the difficulties this might entail. At St Nazaire, they are expert at ensuring that when it comes time to put various pieces of the package together, they are all in the right place at the right time."

The preceding article was provided by classification society Lloyd's Register. For more information, please visit: www.lr.org.