88 AUGUST–SEPTEMBER 2019 | International Boat Industry ibinews.com
TECHNICAL
TECHNICAL FEATURE | VAN OOSANEN
A Hull Vane on a 2om
Jetten motoryacht“In working on the winged keel, that’s where the
idea for the Hull Vane was born,” Hull Vane sales
manager Bruno Bouckaert told IBI. “Fuel prices
were high so there was an immediate potential to
improve the efficiency of the performance of yachts
and commercial vessels.”
To date, Hull Vane BV has
delivered 21 units, more than half
went on yachts. “The rest are
coast guard and patrol vessels,
ferries and offshore craft, says
Bouckaert. “We now have orders
for at least 20 more. Again, a
yachts-commercial mix.”
The first Hull Vane went
on the 42m Heesen-built Alive,
launched in 2014. It makes
the yacht as fast with twin 12V
engines as with twin 16V ones
and no Hull Vane. It also boosted
Alive’s range by 23% to 4,000
miles. Net result: a smaller engine
room, more onboard comfort. As
in any vehicle, more efficiency
also means less noise.
The Hull Vane is for medium-
speed and fast displacement
vessels, typically the ships that
make waves, without being light enough to enter
the planing speed range.
The Sunseeker 161 flagship Icon Yachts of the
Netherlands is building, will have Van Oossanen’s
Fast Displacement Hull Form which generatesefficiency over its entire speed range. Sunseeker
CEO Andrea Frabetti says add a Hull Vane and
combined fuel savings will rise up to 30%. “A truly
remarkable result!”
The Hull Vane is an underwater wing that
converts the stern wave into forward thrust. The
lift’s vertical component raises
the stern, keeping the bow
down at high speed. It also acts
as a passive motion damper for
better seakeeping.
In his AC salad days, Van
Oossanen experimented with
rudder winglets “that created
forward force,” says Bouckaert.
In 2003, a Hull Vane went on
the French AC entry Le Defi
Areva. But held by a single strut,
it bent badly and had to be
removed.
Improving matters was the
breakthrough of Computational
Fluid Dynamics. “These let us
better calculate currents around
a ship,” says Bouckaert. “We
could see much better the Hull
Vane effect on the ship and its
wake. It led to better designs at
lower costs. We look at a ship with and without a
Hull Vane and run the software across dozens of
versions, varying parameters which define the Hull
Vane geometry and position. As every ship has a
different hull, it also needs a different Hull Vane. The winged keel of AC winner
Australia II inspired the Hull Vane