The Norwegian Epic was only delivered to the Norwegian Cruise Line back in 2010, but the company understands the need to make improvements to the ship. One system that takes the most pounding on any cruise ship is its propulsion and so has looked to Rolls Royce to upgrade the package.
Rolls Royce has worked on an innovative permanent magnet tunnel thruster, which is a far better solution than the current one. There are several advantages to such a system, one of which is the reduction of noise, although there will also be a noticeable difference in the amount of vibration, as this will also drop considerably.
Another advantage, one that will appeal the Norwegian is that there will be an increase in power output by as much as 25 per cent, even with using the same size propeller. Repairs will also become far easier, as the system can be removed underwater, meaning no waiting for an opportunity to get into a dry dock.
The chairman from Rolls Royce seems very happy that Norwegian is the first cruise line to opt for the new propulsion package, and hope other companies will follow. For more details you can read the full press release below
Rolls-Royce press Release
ROLLS-ROYCE PERMANENT MAGNET TECHNOLOGY FOR NORWEGIAN
CRUISE LINE TO HELP INCREASE PASSENGER COMFORT THROUGH
REDUCED NOISE AND VIBRATION
Rolls-Royce is pleased to announce that Norwegian Cruise Line has selected a highly
innovative and efficient Rolls-Royce permanent magnet tunnel thruster to upgrade the
propulsion package onboard Norwegian Epic.
The permanent magnet tunnel thruster offers numerous advantages over traditional
tunnel thrusters including significant reduction in noise and vibration, an increase in
power output of around 25% from the same size propeller, and is removable
underwater eliminating the need for dry docking.
Jay McFadyen, Senior Vice President – Marine Services, Americas, Rolls-Royce said:
“We are delighted that Norwegian Cruise Line is the first cruise customer to select our
new permanent magnet tunnel thruster as an upgrade to an existing propulsion
package. Passenger comfort is a top priority for cruise lines, and the reduction of both
noise and vibration, which our permanent magnet technology provides, is of paramount
importance to successful cruise operators like NCL.
“This highly innovative and cutting edge permanent magnet technology is suitable for a
range of applications in both merchant and offshore vessels, where exceptionally low
noise levels, high power output, and rapid response to power demand will benefit
operators, crew and, very importantly, passengers alike.
“What we have seen so far through the experience of our first permanent magnet
tunnel thruster in operation on the Rolls-Royce designed Olympic Octopus, a highly
advanced offshore anchor handling vessel, is that a permanent magnet motor thruster
is quiet, efficient and durable. It is capable of running for thousands of hours in
intensive dynamic positioning (DP) mode, where rapidly varying loads and alternating
thrust directions are the norm.”
The permanent magnet tunnel thruster design concept comprises a permanent magnet
motor in a rim, which drives the propeller in the centre. The permanent magnet motor
consists of two main parts – a stator that carries a number of electrical coil windings,
and a rotor fitted with a number of very strong permanent magnets. A rotating magnetic
field is created by the stator which interacts with the fields of the permanent magnets
on the rotor, which generates force to drag the rotor around, providing the mechanical
Other benefits of permanent magnet technology include the freeing up of space directly
above the thruster where traditional tunnel thruster motors are located, and a
symmetrical design that gives equal thrust to port or starboard. It is available in
1600mm and 2000mm diameter.