When Oasis of the Seas sets out on its inaugural voyage in December 2009, Royal Caribbean will show once again that it observes no limits when it comes to innovation at sea.

At 225,000t and costing an estimated $1.2bn, Oasis of the Seas will be almost 50% larger than the industry’s next biggest cruise ships – Royal Caribbean’s Freedom Class of three luxury liners. Currently under construction at STX Europe’s Turku shipyard in Finland, Oasis of the Seas will span 18 decks and rise 65m above the waterline. It will be 361m long, 47m wide and will carry more than 5,400 guests and a crew of 2,800.

“While the size of the ship is obvious, this is not what makes it so innovative,” says Toivo Ilvonen, project director, Oasis Class, STX Europe. “The original intention was to create new passenger experiences. So, to incorporate all the activities, we had to build a bigger ship. With so many people on board, safety for passengers and the environment was a prime consideration.”

“Royal Caribbean observes no limits when it comes to innovation at sea.”

Neighbourhood watch

The hull is made of two central structures, which is most obvious in Central Park, one of the ship’s seven themed ‘neighbourhoods’, where the centre of the ship opens up to the sky with inward-facing balcony cabins. It features lush tropical grounds that span the length of a football field, with seasonal flowers and trees, some reaching several decks high. Irrigation and drainage systems have been installed to ensure the plants stay healthy, says Ilvonen.

“Creating Central Park has been challenging given that it is a permanently wet area, containing cooking facilities,” he explains. “Technical aspects, such as materials selection and the irrigation system were a real challenge, as well as making sure that the overall environment works with specific restaurant areas.”

The Boardwalk, which was inspired by English and American seaside piers, includes the AquaTheater, an amphitheatre-style space at the stern that will hold choreographed fountain shows set against a stunning ocean backdrop. “It is one of the most technologically advanced areas of the ship,” says Ilvonen, “with three custom lifts, two diving boards and a cantilevered stage that rises and falls to suit performances.”

Other firsts at sea are a full-sized traditional-style carousel and, suspended nine decks above, a thrill-seekers’ zip line that allows riders to speed 25m diagonally across the open-air atrium.

The Royal Promenade features the Rising Tide Bar, the first moving bar at sea, which will rise vertically to a height of three decks. Suspended above the Globe and Atlas pub, a hydraulically controlled bridge will unfurl to extend over the Promenade as a viewing platform.

Accommodation features include 28 loft-style suites, which will offer spectacular ocean views, courtesy of their high positions on the vessel and their floor-to-ceiling, double-height windows.

Each loft will measure 51m² or larger. The ship’s only Royal Suite will house a baby grand piano while the Presidential Family Suite is capable of housing up to 14 people. There are also six AquaTheater Suites, ten Owner Suites, four Family Suites, 30 Grand Suites and 2,700 staterooms.

Safety and efficiency

Not satisfied with creating innovations in size, features and entertainment, Oasis of the Seas will also set new industry standards for passenger safety, fuel efficiency, and ship manoeuvrability.

With over 8,000 passengers and crew, evacuation is an essential consideration, particularly given the potential for bottlenecks in passenger flow.

Oasis of the Seas will span 18 decks and rise 65m above the waterline.”

According to Ilvonen, a ship the size of Oasis benefits from a safety standpoint. “It’s all down to the layout design and operations behaviour,” he says. “The size of the vessel allows facilities to be extended to cope with large numbers of people. To avoid bottlenecks, onboard shows and events will take place at different times, allowing passenger numbers to be spread throughout the ship.”

Extensive fire and safety simulations were analysed in association with classification society Det Norske Veritas. “Open areas are also divided into fire zones, with fire safety systems and equipment in place according to the latest IMO rules,” he says.

At the core of the vessel’s safety innovations is a dedicated command centre located behind the bridge, which will operate all safety aspects of the ship, including the watertight doors, fire detection systems, sprinklers and 500 CCTV cameras. The horizontal atriums can be closed off by 15m A60 roller shutters, while signage throughout the vessel guides passengers to the assembly stations. LCD TVs and the ship’s public address system will provide safety instructions.

The ship’s 18 lifeboats, which can carry up to 370 passengers each, are over twice the size of normal lifeboats, which usually hold up to 150 people. They are positioned so that they can be launched in one vertical movement and are equipped with global positioning systems, windows, stretchers and toilets.

Power house

Given the tremendous size of Oasis of the Seas, most people would be forgiven for thinking that the vessel would be unwieldy, difficult to manoeuvre and that its carbon footprint would be a considerable cause for concern. “This is not the case,” says Ilvonen. “Oasis of the Seas will be working towards a 10% to 20% improvement on power consumption per passenger, consuming less fuel than alternative solutions and achieving high performance levels compared with the Freedom-class vessels, which are already top-quality.”

“The AquaTheater is one of the most technologically advanced areas of the ship.”

The ship will be powered by a dual machinery system that provides a back-up should one fail, with six Wartsila engines: three 16-cylinder V-type engines, each 18,480kW; and three 12-cylinder V-type engines at 13,860kW each. The ship’s total power will be 97,020kW.

Like most of the vessels in Royal Caribbean’s 21-ship fleet, Oasis of the Seas will be steered by ABB’s Azipod azimuthing podded propulsion system, which provides vessel propulsion and steering in a single control unit.

Compared with conventional shaftline propulsion, the electrically-powered Azipod enables more payload to be transported at higher speed, while using less energy, according to ABB.

The system includes three 20MW Asea Brown Boveri Azipod propulsion units, three ACS6000 medium-voltage drives, six main generators, 11kV main switchboards, six propulsion transformers, four thruster motors, distribution and propulsion excitation transformers, and substation switchgear. Each pod contains its own dedicated switchboard.

The propellers are driven by electric motors contained within the sealed pods with the props mounted on rotating Azipods, which can turn 360°, eliminating the need for a rudder.

Although the ship will be sailing in the relatively calm waters of the Caribbean, a pair of built-in Blohm+Voss stabilisers will prevent any rolling, holding the ship in place even when facing gales of up to 40kt.

Green factor

Oasis of the Seas was built with its effect on the environment a priority, according to Ilvonen. “It starts from the bottom of the ship,” he says. “The hull has been optimised, and painted with non-toxic silicon paint, which will help reduce the ship’s drag in the water. The propellers are more efficient than their predecessors, and the main engines are common-rail types with latitude technology. Air conditioning can be switched off automatically and the lighting system uses energy-efficient bulbs such as LEDs.”

“Accommodation features include 28 loft-style suites, which will offer spectacular ocean views.”

The ship will use duel fuels, so that when it is in harbour low-sulphur fuels will be used to reduce smoke pollution.

A Hydroxyl advanced wastewater purification system will be installed for purifying black and grey water, while waste heat from cooling water and exhaust gases will be recycled.

“An exhaust gas scrubbing system will be in place and the vessel is prepared for cold ironing if required,” adds Ilvonen.

With Oasis of Seas out of the dry dock, preparation for sister ship Allure of the Seas is now underway. When it launches in 2010, it will be interesting to see what the next generation of innovations this Oasis Class vessel will bring.