the system’s roll sensor, this should
enable them to react to any lean or roll
and correct it almost instantaneously.
Their ability to tuck away behind the
transom will also be handy when it
comes to berthing in a marina or
manoeuvring in tight spaces.
LOW-SPEED MODE
At slower displacement cruising
speeds, the fins swivel round into
their extended position where
they will rotate up and down in
the same way as the high-speed
mode. Although the slower speed
of the water passing over them
won’t generate as much pressure,
their greater distance from the
centre of roll ensures they will
still create more than enough lift to
counteract any side-to-side rolling.
In fact, the long, thin, high-aspect
ratio design of the fins, similar in
shape to a glider’s wings or the
pectoral fins of a humpback whale,
not only create 50-75% less drag than
the equivalent surface area of
conventional fins but are also more
efficient at generating lift where it’s
needed the most.ZERO-SPEED MODE
Finally, when the boat is at anchor
and unable to rely on water passing
over the fins to create lift, it reverts
to the same actuator used to
extend and retract them to flap
them up and down like a pair of
wings. Once again, the high-aspect
ratio design of the fins, the extra
leverage gained from being further
away from the boat’s roll centre
and the fact that the whole fin
is moving up and down rather
than pivoting around an axis is
claimed to make them more
effective than conventional fins.
Although DMS Holland makes no
reference to it, we suspect that it
may also reduce the paddle effect
that causes some boats to ‘swim’
over their own anchor.ONE-STOP SOLUTION
Patrick Noor, co-owner of DMS
Holland, says, “Since there is currently
no single system that performs
optimally at both high speeds and
at low speeds as well as at anchor,
often multiple roll-damping systems
have to be installed on one yacht.
Soon, with our new system, one
roll- damping system on board will be
enough without having to compromise
on stability at different speeds.”
Despite these claims, there is
one obvious drawback of the new
system – the position and size
of the fins when retracted makes
them unlikely to be suitable for
twin sterndrive or multiple outboard
engine installations. This rules out
the majority of sportscruisers below
45ft, most of which are powered by
twin sterndrive setups. However, for
shaftdrive or IPS-powered boats, this
does look like a very intriguing new
prospect. The AntiRoll technology hasalready been proven to work on much
larger boats – a 37m Van der Valk
was fitted with it last year, winning
the approval of the ship’s captain
and crew, so there is no reason
it won’t work equally well on smaller
production craft.TESTING UNDER WAY
According to DMS, a number of major
shipyards and dealers have already
shown interest in the system and
have indicated a willingness to test
it on one of their models. Alexander
Jonkers, owner of the Dutch Fairline
and Jeanneau dealer, Jonkers Yachts,
has agreed to help test the system
on one of his craft, adding, “I can’t
wait to be able to offer the system to
my Fairline and Jeanneau associates.
In the meantime, I will support DMS
Holland in the development and the
first prototype will be tested with us.”
Full details of the new system will
be revealed at the METS equipment
show in Amsterdam later this year
with the first deliveries of production
systems scheduled for early 2019.
DMS Holland hasn’t yet given
any indication of pricing but with
so many players now offering
stabilisation systems, it will have
to be competitive to make inroads
into an already crowded market.
Contact http://www.dmsholland.comLow-speed mode – the wings are
extended and rotate to create
lift as water passes over themHigh-speed mode – the wings tuck
behind the transom and twist up
and down like active trim tabsZero-speed mode – the wings remain
extended but now they fl ap up and
down to create lift and prevent rollCo-owners Arnold van
Aken and Patrik NoorThis 37m Van der Valk has already
been fi tted with the larger
custom-made AntiRoll systemBOAT MASTER NEWTECH