Oasis-class cruise ship

The Oasis class is a class of 7 Royal Caribbean International cruise ships. The first two ships in the class, Oasis of the Seas and  Allure of the Seas, were delivered respectively in 2009 and 2010 by STX Europe Turku Shipyard, Finland. A third Oasis-class vessel, Harmony of the Seas, was delivered in 2016 built by STX France. A fourth vessel, Symphony of the Seas, was completed in March 2018. As of March 2022, the fifth Oasis-class ship, Wonder of the Seas, was the largest cruise ship in the world. A sixth ship, Utopia of the Seas, is currently being built for entry into service in July 2024 with a seventh to follow in 2028.

The first two ships in the class, Oasis of the Seas and Allure of the Seas, are slightly exceeded in size by the third ship, Harmony of the Seas. As of 2022, all ships of the Oasis class rank amongst the world's largest passenger ships although the title of overall largest is now held by Icon Class lead ship Icon of the Seas. This means that Utopia of the Seas will be the first ship in the class not to hold the title of the world's largest cruise ship when entering service in 2024.

Ship features
The Oasis-class ships surpassed the earlier Freedom-class cruise ship ships as the world's largest and longest passenger ships. Oasis of the Seas is also 8.5 m wider, and with a gross tonnage of 225,282, is around 70,000 tones larger. Oasis-class vessels can carry over 5,400 passengers.

Public areas
Oasis-class ships are split into a number of different themed neighborhoods. Common to all ships are Entertainment Place, Central Park, Boardwalk and Royal Promenade.

Oasis-class ships feature a split structure, with the 5-deck high "Central Park" and "Boardwalk" outdoor areas running down the middle of the ship. These areas feature tropical gardens, restaurants, shops, and a working carousel.

Technical details
The displacement—the actual mass—is estimated at 100,000 tonnes, equivalent to the displacement of a Nimitz-class aircraft carrier.

To keep the ship stable without increasing the draft excessively, the designers created a wide hull. The cruise ship's officers were pleased with the ship class's stability and performance during the transatlantic crossing, when the vessel slowed and changed course in the face of winds "almost up to hurricane force" and seas in excess of 40 ft.

The ship's power comes from six medium-speed, marine-diesel generating sets: three 16-cylinder Wärtsilä 16V46D common rail engines producing 18480 kW each and three similar 12-cylinder Wärtsilä 12V46D engines producing 13860 kW each. The fuel consumption of the main engines at full power is 1377 USgal of fuel oil per engine per hour for the 16-cylinder engines, and 1033 USgal per engine per hour for the 12-cylinder engines.

The total output of these prime movers, some 97020 kW, is converted to electricity, used in hotel power for operation of the lights, elevators, electronics, galleys, water treatment plant, and all of the other systems used on the operation of the vessel, as well as propulsion. Propulsion is provided by three 20000 kW Azipods, ABB's brand of electric azimuth thrusters. These pods, suspended under the stern, contain electric motors driving 20 ft propellers. Because they are rotatable, no rudders are needed to steer the ship. Docking is assisted by four 5500 kW transverse bow thrusters.

The ship carries 18 lifeboats that hold 370 people each, for a total of 6,660 people. Inflatable life rafts provide for additional passengers and crew.

Generations
There are informally three generations of Oasis-class ship. The first generation (2009–2010) consists of Oasis of the Seas and Allure of the Seas. The second generation (2016–2018) consists of Harmony of the Seas and Symphony of the Seas. The third generation (2022–2024) consists of Wonder of the Seas and Utopia of the Seas.

The second generation introduced new bars and restaurants from the first-generation Quantum class, the Ultimate Abyss dry slide, a new waterpark and an Escape Room. The H2O Zone kids pool was replaced with an upgraded kids facility called Splashaway Bay.

The third generation of ships, described as "Oasis Plus" by some media sources, are marginally bigger, with around 200 additional guests at double occupancy and 100 additional crew. The third-generation includes a refurbished pool deck with a large movie screen and an additional pool on board, though far fewer hot tubs. The adults-only pool area is now enclosed and climate-controlled. It also has a new neighborhood: the Suite Neighborhood. The ship's buffet is located on Deck 15 aft rather than Deck 16 under the funnel and is the largest buffet in RCI's fleet. Other additions include a new playground and new food and drink venues.

Ships in the Oasis Class
The oasis class of ships is currently made up of 5 vessels, with a sixth, Utopia of the seas, joining the fleet soon. A further 7th ship will join the fleet in 2028. The oasis class is split into three sub classes, first generation, second generation (oasis plus) and third generation (oasis ultra).

Ship construction


Oasis of the Seas, the first vessel of the class, was ordered in February 2006 and designed under the name "Project Genesis". Her keel was laid down in December 2007 by STX Europe Turku Shipyard, Finland. The name Oasis of the Seas resulted from a competition held in May 2008. and full financing for Oasis of the Seas was secured in April 2009. The ship was completed and turned over to Royal Caribbean on 28 October 2009. Two days later, she departed Finland for the United States.

While exiting the Baltic Sea, the vessel passed underneath the Great Belt Fixed Link in Denmark in October 2009. The bridge has a clearance of 65 m above the water. Oasis of the Seas normally has an air draft of 72 m. The passage under the bridge was possible due to retraction of the telescoping funnels, and an additional 30 cm was gained by the squat effect where vessels traveling at speed in a shallow channel are drawn deeper into the water. Approaching the bridge at 23 kn, the ship passed under it with less than 2 ft of clearance.

Proceeding through the English Channel, Oasis of the Seas stopped briefly in the Solent so that 300 shipyard workers who were on board doing finishing work could disembark. She then left for her intended home port of Port Everglades in Fort Lauderdale, Florida. The ship arrived there on 13 November 2009, where tropical plants were installed prior to some introductory trips and her maiden voyage on 5 December 2009.

The keel of the second ship, Allure of the Seas, was laid on 2 December 2008 at the STX Europe Turku shipyard, Finland, during a ceremony involving Royal Caribbean and STX representatives. She was launched on 20 November 2009, with further outfitting taking place while afloat in the shipyard. Allure of the Seas was delivered to Royal Caribbean on 28 October 2010. She left the Turku shipyard on 29 October 2010, heading directly to her home port of Port Everglades. The ship is equipped with telescoping funnels to pass under bridges such as the Storebælt Bridge, which she passed on 30 October 2010. While media has reported that there was only 30 cm of clearance, the mean water level was closer to 2 - 3 m. The squat effect, where vessels traveling at speed in a shallow channel will be drawn deeper into the water, did not have significant effect on the draft of the vessel.

Royal Caribbean confirmed in October 2012 that they were engaged in negotiations to build the third Oasis-class ship, which became Harmony of the Seas. The ship was ordered from STX France in December 2012, after failing to come to an agreement with the Government of Finland for additional financial support to build the ship at the STX Finland shipyard that built the first two ships. Steel cutting began in September 2013, and the ship was delivered in May 2016. The ship is larger than the earlier Oasis-class ships at an estimated 227,700 GT, 362.15 m in length, and 66 m in maximum width, representing an increase of 2,418 GT and 2.15 m length.

The ship has 2,744 passenger staterooms with a capacity of 6,360 passengers (5,488 double occupancy), an increase of 64 passengers over the previous ships in the class, as well as 1,197 crew cabins capable of berthing 2,100 crew. The ship features an expanded adults-only solarium area and three water slides, a first for Royal Caribbean. It cost about €1 billion (US$1.35 billion) and entered service in May 2016.

In May 2014, Royal Caribbean exercised their option for a fourth Oasis-class ship, which became Symphony of the Seas. Steel cutting began in February 2015, and the name of the ship was announced in March 2017. The ship was delivered in April 2018.

In May 2016, Royal Caribbean signed an agreement for a fifth Oasis-class ship, later named Wonder of the Seas. Steel cutting began in April 2019, and the keel was laid in October 2019. The ship name was announced in October 2019. A hull section was built at Crist at Gdansk and delivered to the yard in November 2019. She was launched in September 2020. Wonder of the Seas entered service in March 2022 as the largest ship in the world. She initially offering Caribbean sailings from Ft. Lauderdale, FL before repositioning to Europe to offer Western Mediterranean sailings from Barcelona, Spain and Rome, Italy.

In February 2019, Royal Caribbean Cruises Ltd. ordered a sixth Oasis-class ship, named Utopia of the Seas. Steel cutting began in Chantiers de l'Atlantique shipyard in April 2022. Keel laying was held in July 2022.

Negotiations about a seventh vessel, to be built as B35 and to be delivered in 2026, were stopped in 2020 because of the coronavirus pandemic. In February 2024, Royal Caribbean and Chantiers de l'Atlantique announced that they signed an agreement for a seventh Oasis Class ship to be delivered in 2028.