Saturday, March 1, 2003
Custom Line mega-yachts have eliminated seasickness. Tested for the first time, and with
enormous success, on "Ziacanaia", hull number six of the Navetta 30 Custom Line of vessels,
the Anti-Rolling Gyro (ARG) stabilisers, patented by Mitsubishi Heavy Industries and which will
be installed on an exclusive basis for the European market on many vessels of the Ferretti
Group, are today a part of the standard equipment on the mega-yachts built by the CRN
shipyard of Ancona under the Custom Line name. More than 70% of the devices purchased by
the Ferretti Group are installed on Custom Line 94’, Custom Line 112’ and Custom Line
Navetta 30 vessels. Thanks to this agreement, signed with the Japanese giant last March and
valid until 2006, the ships turned out by the Ancona shipyard come with the only system in the
world capable of reducing the rolling of a vessel – the chief cause of discomfort particularly
while anchored off the coast or moored at a dock – by more than 50%. In navigation the ARG
are integrated with the stabilising fins with which all Custom Line Yachts are equipped. This
application allows the ships produced by the CRN shipyard to reach a level of technological
excellence absolutely unmatched in the world of pleasure boating. On the strength of the
working relationship with Mitsubishi, the Ferretti Group and the Ancona shipyard enjoy major
competitive advantages, allowing them to satisfy the requests of an increasingly demanding
market. The mega-yachts produced are not only refined and elegant, but also capable of
guaranteeing their owners a cruise of pure pleasure. Exclusivity and relaxation, comfort and
prestige are solidly coupled in these giants of the sea, designed to transform dreams into
reality. It is nothing less than the constant attention focused by CRN on its ship owners that
has led to the achievement of this important objective, which serves as the starting point for
the pursuit of new goals. In fact, given the advantages offered by this technology, the CRN
technical staff are studying the possibility of fitting the ARG on the larger hulls made of
composite materials as well, such as those of the Custom Line 128’ and the new 43 metre
Navetta. The ARG offer a noteworthy decrease in rolling, with the boat moored, as well as
absolute silence and low energy consumption, with no negative impact on the quality of life
onboard or on the performance levels of the vessel. Thanks to these extremely important
features, the device can be operated at night as well, without disturbing the sleep of the ship
owner or his guests. The ARG are based on a well-known principle of physics: the fact that a
gyroscope tends to maintain its vertical axis of rotation parallel to the acceleration of gravity.
When an external cause varies the position, such as the rolling caused by waves, the device
responds by rotating on an axis perpendicular to its own axis of rotation and to that of the
cause of the rolling. In the case of the Mitsubishi ARG, the rotation generated (rolling) is
attenuated by the presence of two dampers calibrated in accordance with the characteristics of
each vessel. The principle of this function, analogous to that of a spinning top, was already
brought to light in the 1930’s, dating back to the period of the world’s first application of a
gyrostabiliser system on a liner ship dates back. An article published in the "Transatlantici"
(Edited by Tormena Industrie Grafiche Genova) recounts how this anti-roll system, based on
the invention of the American researcher and design engineer Elmer A. Sperry, was installed
on the "Conte di Savoia", universally advertised as ‘the ship that doesn’t roll’. The last reports,
giving merit to this system, published in technical magazines date back to 1936, after which
the gyrostabilisers were superceded, essentially due to technical and investment problems, by
traditional fin systems. An ARG consists of a cardanic suspension winch and a single or triphase
electric motor of from 200 to 240 V and 50 or 60 Hz (meanwhile a tri-phase 380 V
motor is currently being studied). The idea evolved from the aerospace sector where similar
technology is utilised to maintain satellites in the correct orbiting position.
Press: FERRETTI YACHTS, Consuelo Bentivogli – tel. +39 0543 474.411
mail: consuelo.bentivogli@ferretti-yachts.com
AD MIRABILIA Via Mascheroni, 19 - 20145 Milano
Contact: Andrea Milanesio- tel. +39 02 438219.27 - mail: milanesio@admirabilia.it
Further characteristics that explain the success of the device include the fact that it can be
installed on any type of vessel, including those already in operation, in a position compatible
with the available spaces onboard and without the need for any maintenance. Additional proof
of the reliability of the technology is provided by the results of the tests carried out by
Mitsubishi, which show an MTBF (main time between failure) of more than 65000 hours. The
following ARG models, identified by a number that corresponds to their capacity to decrease
rolling, are available: MSM-2000 (weight of 290 kg, width of 93 cm), MSM-4000 (700 kg. by 1
metre in width) and MSM-12000 (1,700 kg by 1.65 metres in width). MSM-4000 type
stabilisers are mounted on the Custom Line Navetta 30, Custom Line 94’ and Custom Line 112’
vessels. The type of device installed depends on the weight and stability of the ship, and its
power, or anti-rolling capacity, must be directly proportionate to both. This means that the
most stable vessels are also the most sensitive to rolling, explaining why, in the case of two
different vessels of equal weight, a Navetta 30 and a Custom Line 94’, the former is equipped
with three ARG (two in the stern garage and one in the engine room), while the latter, which is
more stable, has four (all in the engine room). There are also four on the Custom Line 112’
(three in the garage and one in the engine room). This accomplishment gives the Ancona
shipyard technological leadership over its competitors, providing Custom Line vessels with a
strategic first in Europe while making them even prouder than before to plough through the
waves of seas throughout the world.