Taking the liberty

The largest cruise ship in the world, packed with on-board entertainment, has just set sail for the first time. Niall Firth reports on the engineering challenges of building the £400m vessel

Cruise ships have something of an image problem. Saddled with the reputation, possibly unfairly, of being the holiday of choice for the elderly and lottery millionaires, the leisure industry's equivalent of an expensive night at the Bingo has struggled to shake off its fuddy-duddy image since its heyday in the 1970s.

One company doing its best to get younger generations and families to consider cruising as a holiday option is Royal Caribbean, which started life in Norway in 1968.

The Liberty of the Seas

The Liberty of the Seas is the second ship from the now Florida-based cruise giant's Freedom Class, joining its elder sibling, The Freedom of the Seas, as the word's largest passenger vessel. It has just started taking its first paying passengers on cruises that start from £330 for a seven-night excursion around the eastern Caribbean.

Not that guests will see much of Jamaica or the Cayman Islands; this £400m monster comes packed with enough on-board entertainment to keep even the most ardent 'landlubber' occupied.

The Liberty's 14 decks are packed with 12 bars, two nightclubs, a casino and shops. With ice rink, boxing ring, golf simulators and basketball court, the sporty are well-catered for too. Then there is the FlowRider machine that recreates a Californian surfing experience by churning out 30mph waves, a nine-hole miniature golf course, 50ft climbing wall and a water park replete with fountains and whirlpool baths.

However, this dedication to fulfilling every possible whim of the potential 4,360 passengers on board takes its toll on the engineers tasked with designing this floating city, said Harri Kulovaara, Royal Caribbean's executive vice-president of maritime.

'It is one of the most challenging engineering objects in the world,' he said. 'The ships are entirely non-standard and are built like prototypes, packed with complex engineering inside.'

The ship's 160,000 tonnes were cut and welded from several hundred thousand pieces of steel at the firm's shipyard in Finland while the Liberty's navigational, power and communication systems are all custom-made, non-standard systems that pull the very latest in technology together. Kulovaara claimed the ship's captain can control this giant ship using a joystick to within 10-15cm in space using GPS.

'The Liberty of the Seas is like combining a power station, a plane and a four-star hotel with a ship. It's extremely challenging but that's its charm really,' said Kulovaara.

According to Kulovaara, taking the record for the world's biggest passenger ship was never Royal Caribbean's ultimate goal. 'Building the biggest was never the sole purpose of the Freedom class but we just had so many ideas as to what we wanted on board that the ship's design just grew to accommodate this.'

One of the biggest challenges in the Liberty's design was having to deal with the sheer amount of water required to service not only the ship's washing, cooking and drinking needs but crucially all of the water-based entertainment activities. Surfing pools, waterparks and whirlpools all require huge volumes of water. This was one of the reasons for the ship's size, said Kulovaara.

An on-board surfing machine

'We wanted to take the pool decks to the next level in design. However, water is heavy and we needed larger ships to accommodate this. When you have this kind of weight you need reinforced structures underneath the pools, as well as extra machinery to pump the water,' he said.

The ship's design engineers also need to design around the sound of the pool's machinery so that the noise of the gigantic pumps was barely perceptible in the five-star restaurant only a deck below.

Water treatment on board the ship was also a major consideration. All the water the ship uses is treated to exceptionally pure quality before being pumped around the ship. Liberty takes on sea water and processes it through a desalination plant, where it is then pumped throughout the ship. 'It tells you much about the ship's complexity, that we take the sea water and produce close to 2,000 tonnes of water in a day, which is then purified and made into drinking water,' said Kulovaara. 'This is cutting-edge technology.'

These vast amounts of water are not just treated in one direction either. Each day all of the wastewater created by the ship's many passengers and facilities is then purified before being allowed back into the sea.

The ship's wastewater treatment plant combines all of the water flows from throughout the ship then treats it in two different stages. A bio-reactor cleans the water to a certain level before it is purified to what Kulovaara called 'near-bathing quality' using an advanced filtration machine.

The Liberty of the Seas is also an all-electric ship (see feature, page 20) in that its azimuth propulsion units are electrically driven by powerful 16MW electric motors, which can rotate with 360º freedom of movement, making the ship extremely manoeuvrable.

Gone, too, are the days when being on board a cruise liner in the middle of the ocean meant you were safely out of reach of business calls and relatives. The Freedom Class comes equipped with a communications system that links via satellite to the mainland, giving complete mobile coverage anywhere on the ship. Wireless internet access is also available on board — a trickier proposition than it might seem, according to Kulovaara.

'It's easy on shore to get all this wireless data coverage using cables, but via satellite link it's a lot trickier. The aerospace industry has tried this before but couldn't really manage it like we do and it is now standard issue on these ships.'

The Liberty of the Seas is also running tests of RFID on board, as a feasibility study to see how this can benefit its passengers. Children left to run wild in the ship's many play areas are fitted with RFID-tagged wristbands, so their movements can be tracked wherever they are.

Royal Caribbean has a long and distinguished cruise liner heritage. Its first ship in 1968 could accommodate only 400. 'Every generation is 30-40 per cent larger than the previous generation — its an evolutionary development,' said Kulovaara. 'The complexity of these massive projects is how to handle all of the different elements — such as the mass volume of the internal machinery — and put it together in a harmonised manner in a relatively short timeframe.'

With the third and final vessel of the series, Independence of the Seas, scheduled for delivery in 2008, Royal Caribbean looks to be upping the stakes in the cruise ship industry.

If it can show cruise holidays can be more than cabarets, 'all-you-can-eat' buffets and deck quoits, it could also prove that bigger really is better.