The ship's structure has been reinforced compared to cruise ships, Gatepaille explained, adding that at the owner's request, the yard has calculated 40 years of service for the ship, compared to the normal 25 years for passenger vessels.
When Gatepaille was interviewed by Cruise Industry News, he had just come back from the second set of sea trials. "We are very satisfied with the ship's behavior in the seas," he said. "The vibration level is very low, there is no slamming, and we achieved a higher speed than contracted."
During the last sea trials, there were 700 people onboard including workers laying carpets, installing furniture, and air-conditioning. As the movement of the ship was very small, these workers were able to go about their normal work routines, according to Gatepaille.
However, building a ship such as the QM2 can be a tricky proposition due to its unusual size. "There were no analogies to other ships," Gatepaille explained. "The steel structure is stronger compared to other cruise ships due to the severe sailing conditions encountered in the North Atlantic and the 40-year fatigue level used as basis for our calculations.
"Even the outfitting was unusual as the ship's length is not proportional to her size. You had to apply different logistics to get materials, equipment, and boxes onboard. The key is accurate planning so everything happens in the proper sequence so there are no bottlenecks," Gatepaille noted.
The contract for the QM2 was signed in November 2000 and the first steel cutting took place in January of 2002. The keel laying followed in July of 2002, with the bow being attached in January of 2003. The ship was transferred to the outfitting basin in March. The pods were attached in June, with the first set of sea trails in late September and the second set in early November.
Biggest Powerplant at Sea
The QM2 also features one of the most powerful power plants at sea. Instead of going with a new and largely unproven engine application with six diesel engines that the owners had been considering, the yard recommended using the same proven power plant as on the Coral Princess, only doubling everything. So while the Coral Princess has two diesel engines and one gas turbine, the QM2 has four diesel engines and two gas turbines. "We were able to install twice the power without having to take the risk on new technology," Gatepaille pointed out. "We submitted all our calculations to the owner, who agreed with us that our solution was safer and more practical."
The QM2 will also feature four pods, instead of the normal two, or three in the case of the Voyager-class. The difference is that the pods on the QM2 will feature electrical rather than hydraulic drives for rotation. Gatepaille said that the electric drives were more precise and quicker.
With four diesels in the bottom, two turbines at top, and with four pods, Gatepaille is confident there is enough redundancy to keep the QM2 steaming, even if some equipment should fail.
Naval Architects Rule
While interior designers often ask naval architects to move columns or otherwise work around the interior design, in case of the QM2, it was the other way around, according to Gatepaille. "Safety and the soundness of the structure came first," he said. "We were able to tell the designer that they had to work around columns or bulkheads instead."
During the design stage, extensive model tests were carried out, testing as many variables as possible, focusing on the ship's sea-keeping abilities, including a range of swells, strong winds, and several configurations of stabilizers.
"We did perfect in the tests. There was no green water on the ship - only spray in the worst condition," Gatepaille pointed out.
He said that tests included three wave heights - 14, eight, and four meters - and that even in the worst condition more than one third of the ship was beneath the vertical acceleration curve when people tend to get seasick.
Due to the size of the QM2, the movements are smaller than on a Panamax ship, Gatepaille said.
The French naval architect is also pleased with the appearance of the ship, which he credited to Stephen Payne and his team. "She is sleek and elegant without the vertical lines of most passenger ships today," he noted. "People on shore who saw her at sea described her as beautiful," he added.
Continued Gatepaille: "As a naval architect, the first thing I look for is the ship's behavior at sea - how the ship sits in the sea; if the movement is light; if there is slamming; and I look at the wake to see if the propellers are working right. This ship's behavior was very impressive," he said. - Oivind Mathisen