A contract has been signed for the construction of a third Quantum-class ship for Royal Caribbean Cruises for delivery in mid-2016.

The as-yet-unnamed 4,180-passenger vessel will join the Royal Caribbean International fleet, alongside Quantum of the Seas, which will make its maiden voyage in 2014 following a preview in Southampton, and Anthem of the Seas, due to enter service in 2015.

The deal means that projected capital expenditure for 2013, 2014, 2015 and 2016 are $700 million, $1.2 billion, $1.2 billion and $2.1 billion, respectively, according to the company

Including Quantum III, the company’s capacity growth rate from 2012 to 2017 will be approximately 4% a year.

Design of the new generation ship includes an advantageous configuration which includes a greater proportion of higher priced cabins and that it achieves some of the greatest energy efficiencies at sea, the line said.

Chairman and chief executive Richard Fain (pictured) said: “We are creating a compelling experience for vacationers with innovative design, winning service, and appealing destinations around the world.”

Vice chairman Brian Rice added: “This order follows our stated goals of moderate growth, driving improved returns and leading to an investment grade rating.”

Royal Caribbean International president and chief executive Adam Goldstein said: “We are encouraged by the very positive response we received from travel agents and consumers when we first announced some of the unprecedented offerings on Quantum Class last month.

“The Quantum class will offer vacationers more unexpected activities in the most extraordinary spaces, and a third ship will offer even more opportunities for vacationers to experience Quantum cruising.”

Quantum ships span 16 decks, encompass 167,800 gross registered tons, carry 4,180 guests at double occupancy and feature 2,090 cabins and suites.