The birth of a transatlantic giant

The keel laying of Cunard Line?s Queen Mary 2 (QM2) at the French shipyard of Chantiers de l?Atlantique on July 4 represented a landmark in the history of passenger-ship building. This newbuilding, costing £540 million ($788 million), will be the largest, longest, tallest, widest, and most expensive passenger ship ever built. Its construction will involve 300,000 pieces of steel cut and welded into blocks. Some of the 94 pre-outfitted blocks weigh more than 600t each and will amount to a total estimated weight of more than 34,000t divided into 42 zones.

According to Patrick Boissier, chairman and ceo of the shipbuilder, the building of QM2 demonstrates the dramatic improvements that have taken place in shipbuilding productivity. All steelwork for the hull and superstructure is scheduled for completion in March next year, a construction period of just over eight months. Just nine months later, in December 2003, QM2 is scheduled to complete sea trials before embarking on its maiden voyage in January.

QM2 will feature classic Cunard hallmarks such as sweeping staircases, expansive promenades, stylish restaurants and grand public rooms. The sheer volume of the vessel, 150,000g, has enabled the line to create one of the most spacious passenger ships in the world for the 2,620 passengers (lower berths).

The QM2 project employs teams of naval architects, engineers and maritime experts, including the marine interior design firms of SMC-Tillberg and Designteam, both based in London. Unlike other modern cruise ships, the design has been structure led with interior architects working around the structural arrangements rather than the other way round. This was largely dictated by the fact that the vessel will have a 40 year fatigue life and have the capability of operating in the sometimes harsh environment of the North Atlantic.

This no-compromise attitude manifests itself in many areas of the ship?s structure. Pillars have been made continuous throughout the ship as far as practicable while structural bulkheads have been pierced as little as possible to provide maximum strength. In addition, the ship will have thicker hull plating, higher speed, lower block co-efficient hull and classic liner configuration such as set-back superstructure, a high bow with a significant flare, tiered upper works and a large Normandie-type breakwater and flush forecastle deck.

Facilities include 1,310 fully equipped staterooms and suites, nearly three quarters of which will have a private balcony. Public spaces range from a three-storey dining room to bars and lounges to the first sea-going planetarium.

Technical outfit

Two pairs of Rolls Royce Brown Brothers stabilisers give a claimed 70% roll reduction in difficult stern quartering seas. Consideration was given to installing an active anti-rolling tank but investigations indicated that no great improvement would be apparent while the loss of stability and deadweight of such a system could not be justified.

The power plant will be a mixed gas turbine and diesel engine configuration. It is based on two GE LM2500+ gas turbines mounted in a machinery house beneath the funnel and four 16V46C Wärtsilä medium-speed diesel engines in a single engine room. The turbines will burn marine gas fuel oil and will generally be run only when the ship needs to achieve higher speeds, while the diesels will run on heavy fuel oil and enable the ship to attain a cruising speed of between 24 and 26 knots. Electrical alternators for the power station will be supplied by ABB Finland while Valmarine will supply the integrated automation control system.

The plant size has been calculated to provide power for the anticipated 16MW hotel-load together with a maximum speed condition with all prime movers in operation. The diesel engines will have a maximum capacity of 67,200kW and the gas turbines 50MW giving a total power output of nearly 118MW, about twice the power of a 100,000g conventional cruise ship.

High-speed pods

More than two-thirds of this energy will be used to power a state-of-the-art Mermaid podded propulsion system, which has been jointly developed by Rolls-Royce (formerly Kamewa) and Alstom. This system will consist of two fixed and two azimuthing pod units each with a power output of 21.5MW and will be the first ever four-pod installation. It will provide a service speed of nearly 30 knots with low noise and vibration levels and maximum manoeuvrability. The forward pods are non-azimuthing and located outboard of the aft azimuthing units and each will weigh 250t. The propellers will be of a bolted built-up design, each consisting of four 6m diameter stainless steel highly skewed fixed pitch blades with a left and right handed pair being provided for the forward and aft propellers.

These powerful pods were specially developed by Kamewa following an extensive research program to minimise pressure pulses and optimise hydrodynamic efficiency to meet the higher speed requirement of QM2. This resulted in a newly designed asymmetric pod produced to take into account the skewed thrust from the propellers, thus minimising, as far as possible, any interference effects. Interestingly, it was found after the initial tests at MARIN, that the pressure pulse levels were over three times the specified limit. Further trials revealed that out of the different parameters of forward/aft pod interaction, propeller characteristics, direction of rotation and propeller/hull tip clearance, it was the latter which proved to be the most significant. As a result, the pods were repositioned to give the best possible clearances which, at the same time, brought the pressure pulses well within the specified limits.

The other issue which has been the cause of some concern was the ability of pods to steer efficiently at high speeds and, because of this, the first QM2 designs incorporated a small centre-line course keeping rudder aft of the centreline skeg so that the azimuthing pods could be locked during fast transatlantic crossings. Model trials showed that the rudder had to be of a much larger size than originally proposed in order to have any effect and this would increase the drag factor by 2.2%. Not surprisingly, this was deemed unacceptable and, in the end, the plan was abandoned when Kamewa developed electric steering actuation, as opposed to hydraulic motors, for the azimuthing pods which gives precise course control without hunting. Both steerable pods will be fitted with four electric motors in a gear and pinion arrangement which will drive the azimuthing wheel directly and provide enhanced redundancy and control.

Another special feature is the ability to enable QM2 to cruise with one propulsor out of action. Using a shaft brake/ locking system, the propeller of the inoperable pod will be locked while the other three units will still be able to drive the ship at more than 23 knots. Studies are also being carried out to access the feasibility of steering with a single pod in the event of a breakdown of one of the two azimuthing units.

Mats Johansson, director at Rolls-Royce Pod Propulsion, emphasises the considerable developments which the Mermaid podded propulsor system has undergone to meet the very high specifications demanded by the QM2 project. In fact, the QM2 pods are likely to be the precursor of a new range of pods aimed at the medium to high speed market and both Rolls-Royce and Carnival, corporate parent of Cunard, seem confident that the modifications in the design of the Mermaid pods will provide Cunard?s newbuilding with the most efficient and effective propulsion system. Importantly, the ball-bearing troubles which afflicted similar Mermaid units installed on two Celebrity cruise ships (RCCL Millennium-class Summit and Infinity) have been addressed through the modifications and fitting of extra seal rings.

To further enhance manoeuvrability, especially when berthing, QM2 will be fitted with three FP bow thrusters supplied by Rolls Royce. These 3.2MW units will be of the reinforced tunnel design with visco-elastic cement to dampen noise and vibration and will also incorporate butterfly-type doors to eliminate the anticipated drag factor which tests estimate to be nearly 3%.

Bridge command post

The bridge of QM2 will be 45m wide and utilise the latest technology with a lay-out designed to take into account the current ?safe bridge team management? philosophy and using a new idea of presenting information to deck officers to manage the systems. Dispensing with the traditional ?T? bridge design, operators will be able to move freely between displays and controls, all of which will be supplied by Kelvin Hughes. This will consist of a base console incorporating five 23″ flat screen panel MANTA 2300 displays all of which are interchangeable at the operators? discretion and close circuit camera pictures can be shown in the corner of the screens. There will also be two workstations with screens at each bridge wing station.

Two high chairs at either side of the control unit enable operators to have maximum head-height vision while using ergopods to control displays. Kelvin Hughes?s new bridge system will make moving around the bridge easier for operators and give improved access to displays and controls. It will be particularly helpful when the vessel is making difficult manoeuvring operations, such as when docking or when navigating in narrow channels or in busy shipping lanes. The ship?s integrated bridge system will also feature a single joystick on the Captain?s chair, which will enable bridge personnel to control the vessel?s manoeuvres including sideways movements and station keeping.

The flat screen bridge system will facilitate the control of QM2?s navigation systems, radars, dynamic positioning system and engine monitoring, power management displays, water consumption and ballast transfers. The navigation displays will feature an ECDIS system which can be used in two modes ? ECDIS and conning display. A fully adaptive autopilot, which can be controlled from the ECDIS, will comprise an approved automatic navigation and track-keeping system (ANTS) used on one man operated vessels. The navigation

equipment

will also comprise two of the newest available fibre-optic gyrocompasses of the C Plath Navigat 2100 type and a differential global positioning system giving virtually instantaneous updates.

Other primary functions capable of being displayed will include a Doppler log to measure and show longitudinal and transversal bottom track and longitudinal water track speed while the log will also be able to show the depth as a backup to the echo-sounder. The latter will be based on an LCD display system. An electromagnetic log and anemometer giving an integrated speed log and wind data system will provide details on both speed through the water and relative wind data with a true wind option from a single processor.

In regards to safety management systems, there will be a bridge alarm unit which can be connected to up to 10 inputs and the ship will be fitted with an external signal system consisting of four microphones which will detect and indicate the direction of the sound.

Cold storage

equipment

Much of the catering

equipment

is supplied and fitted by MacGregor?s Passenger Ship division and includes provisions stores, refrigeration machinery and cooling distribution systems, galleys, bars, pantries and refrigerated counters, refrigeration machinery and cooling distribution systems. The company will install the many systems over a period of 10 to 12 months.

To give some idea of the extensive range of

equipment

being fitted, MacGregor is supplying all 67 cold store rooms spread over nine decks and occupying a floor area of 2,057m2. This represents by far the biggest project the company has ever had for cold stores.

The cold store rooms can be broken down into three different types, ie main cold stores area (29 rooms occupying 1,557m2), walk-in cold stores and cold stores in the galley area (35 rooms occupying 359m2) and dry stores (three rooms occupying 141m2). MacGregor?s new A-60 rated fire and temperature insulation doors will be fitted to over 60% of the cold store rooms.

The QM2 contract is also MacGregor?s largest order yet for refrigeration machinery. The package comprises four brine chiller units with screw compressors ? rated at 1,200kW, 600kW and 2 x 190kW, brine pumps, air coolers, piping networks and a control and monitoring system. The plant will cool brine to some 60 cold rooms, 300 catering consumers and also, through the 600kW chiller unit, some 20 fan coils as a back-up system for air-conditioning technical rooms. In total about 9,000m of insulated pipes will be used to circulate the brine solution throughout the ship. The piping system is divided in three networks: one at -33oC, one at -10oC and one at +5oC.

An indirect cooling system using brine was selected by Carnival for environmental reasons. The alternative direct expansion system would have required several tonnes of Freon refrigerant in the piping system running throughout the ship. A system that uses a secondary fluid (brine) circulating in the pipe network reduces the refrigerant charge and minimises the risk of refrigerant leaks.

The contract to supply the galleys, bars and pantries was the result of a close collaboration between the ship owner?s naval architects and the shipyard, in which MacGregor participated in supplying design expertise as a pre-contractual service. This meant that the Passenger Ship division?s design team was involved during the first stage of the project to design a complete catering technology system, including the lay-out of provisions stores, preparation areas, galleys, bars and pantries.

After cost comparisons between different alternatives, a detailed technical specification was drawn up to simplify discussions between owner and shipyard through a common understanding of the catering systems. All these solutions are compliant with the latest United States Public Health Service (USPHS) rules and regulations, and take into account the ergonomics of all working conditions. The provisions flow has been considered and devised in a way that secures passenger safety in terms of food hygiene.

Altogether some 2,866 different items of

equipment

will be supplied and installed in eight galleys, 14 bars, 43 pantries and service buffets which will occupy a total area of 4,070m2. As the first part of the contract, the Passenger Ship division will supply and install foundations, tiles, ceiling and partitions on a complete system basis under which MacGregor is fully responsible for compliance with USPHS regulations.

Fire protection

Passenger and crew safety will be enhanced by the comprehensive Hi-Fog fire protection system that will include over 10,000 sprinklers and spray heads, and 58km of stainless steel piping. The large scale of the system is hardly surprising when one considers that the vessel will have 1,310 staterooms accommodating 2,620 passengers.

Produced by the Finnish company Marioff, the Hi-Fog 2000 water mist sprinkler system will be fitted to the vessel?s accommodation spaces. The larger sprinkler spacing of 5m means cost and weight benefits especially in the grand scale public spaces and staterooms. Standard 18m2 cabins will have only one sprinkler, while deluxe cabins will have two, all pre-built into cabin modules. The machinery spaces less than 1,000m3 will have a Hi-Fog total protection system, and the main engine room will have local protection. Other areas protected include the galley ducts, deep fat fryers and incinerators.

The Hi-Fog system on QM2 will utilise the new SPAU 2000 3 pump unit which comprises three motors, each driving two pumps, and is designed so that major parts can be easily removed for servicing. The system incorporates a compact sprinkler connected by ?wet? piping to an electric-driven pump unit. In case of fire, the fast response sprinkler bulb is broken by the heat, the pump starts, and mist is discharged to suppress the fire.

Unique design features

Because of the rough weather conditions prevailing in the North Atlantic and based on experience gained on QE2, it was deemed prudent to locate the lifeboats higher than the recommended IMO height of 15m. Following discussions with the MCA, Lloyds Register and the US Coast Guard, the newbuilding was allowed to have its boats fitted at an elevated position.

However, this had a knock-on effect on the escape stairs since, with the main high density areas and public rooms being located on the lower decks, the requirement for escape routes was more extensive than initially foreseen. Areas such as the dining room, ball room, main lounge and auditorium have a great impact on the size of the stairs needed when coupled with cabin areas within each zone leading to the lifeboat stations and embarkation points. Careful distribution and passenger density within the public rooms enabled a high degree of rationalisation of stairways to be achieved leading to a centralised access to the numerous bars and lounges while an auxiliary side access is also provided.

Another feature which required a creative solution was the hybrid cruise/transom stern. Although the hydrodynamic advantages of the transom were acknowledged, there was some reservation about the possible slamming effect through pitching while there was also an aesthetic requirement to retain the classical cruiser stern. Blending the two styles together has produced a hybrid form which has been successfully tank tested at MARIN.

Extensive wind tunnel tests were carried out at the Danish Maritime Institute (DMI) to ascertain the optimum funnel shape and to assess the comfort levels for the open decks. The funnel shape that was finally adopted has the same overall configuration as that of QE2 including the wind scoop which was modified to provide adequate performance under most conditions. This device was deemed to have an advantageous effect on dispersing the smoke plume and tests showed that a modified scoop arrangement would be beneficial with a slightly higher trailing edge. These comfort tests were also used to determine the best location for side screens, particularly on the open after decks, to provide a comfortable environment even at high transatlantic speeds.

Other novel features include the use of waste heat from the ship?s diesel engines for the evaporation of seawater. Distillation plant onboard will be able to produce enough drinkable water to supply the estimated 1,100t required for daily consumption.

In an interesting bit of recycling, the voice of QM2?s predecessor will be heard once more on the oceans since the whistle will be the same one used on the original Queen Mary, now permanently berthed at Long Beach, California. Compressed air creates the two octaves below the middle C note that will be audible at a distance of 10 miles.