and fabrication techniques. When we showed this to the
chief of naval staff, he said, ‘I want to build one.’”
“There are only a handful of composite boat builders in
the world who are doing vacuum infusion on this scale,”
said Dennis Maconaghie, the shipyard manager for
North Sea Boats. “One of them is right here. You
wouldn’t expect it, but we’ve built 150 boats in 10 years.”
The composite is made by placing layers of carbon
fiber material on both sides of a foam core, and then
using a vacuum process to infuse the laminate with a
vinyl-ester resin. After curing, the structural pieces are
both strong and stiff. Unlike aerospace-grade composites, curing can be done at ambient temperature. No
pressurized, heated autoclave process is required.
“The close-cell foam core is lightweight and provides buoyancy,” Maconaghie said. “The carbon fiber
material is 10 times stronger than steel for its weight.”
According to Maconaghie, the yard currently is producing inshore patrol boats for Bangladesh. The first
two ships are being built at Banyuwangi, and 16 will be
built in Bangladesh. North Sea Boats is training workers from Bangladesh in the techniques of creating
structures from resin-infused materials.
The original trimaran prototype was launched in
August 2012, but a fire destroyed the hull. Because of the
tight delivery schedule, Lundin said the boat was put in
the water quite early. Regulations for the outfitting of military equipment required that the ship be towed to the
local Navy base for security reasons to install the combat
systems, so it had no installed firefighting capability.
“At that stage, it had no military systems on board,
and the ship systems were not all up and running. We
were relying on the shore-based fire protection. There
was an electrical fire close to the fuel tanks. The shore-
based systems were not able to handle a fuel fire that
spread quickly,” Lundin said.
According to Lundin, a short-circuit that ignites the
fuel can happen on any kind of ship.
“It has nothing to do with the material. When 50
tons of fuel burns, it doesn’t matter what type of ship
it is,” he said.
New carbon fiber laminates with vinyl-ester resin
are very resistant to fire and self-extinguishing.
Composites do not transfer heat like steel or aluminum. With the new resins there is more time to get
a fire under control before it spreads.
Combat System Competence
For the Indonesian program, Saab will be the prime
contractor, and North Sea Boats will be supplying the
ship platform. Lundin said Saab is probably the world
leader in installing combat systems into composite
ships because of the Visby program.
“They’ve had experience in working with high-tech
composites together with sensors and installations of
military systems, which is a bit unique and requires special know-how. They were the natural choice,” he said.
Peter Carlqvist, Saab’s general manager for Indonesia,
said Sweden has much in common with Indonesia.
“We have a similar environment with thousands of
islands and shallow water, and we have learned to use
this environment to our advantage to defend ourselves.
We think this ship is exactly what Indonesia needs,” he
said. ”It’s affordable, but has a lot of capability for its
size and cost.”
Saab is providing a proven combat system, with the
Saab Sea Giraffe SG1X 3D surveillance radar — which
is mounted up very high on the single mast tower, giving it 30 percent greater range — along with Saab
CEROS 200 fire-control director and Saab 9LV combat
management system. There are launchers for the Saab
RBS- 15 anti-ship and land-attack missiles, which have
a greater than 135 nautical mile range. The fire-control
system is integrated with the Swedish-made Bofors
“A very big part of the naval fleet here already has
Bofors guns, so it was an easy choice,” Lundin said.
“The multipurpose 40mm gun with its 3P ammunition
provides air defense capability against missiles and air-
craft, and against surface targets. It’s a proven system; it’s
a combination that is totally reliable and highly lethal.
Bofors and Saab both say their systems can work with
anybody’s, but I think this combination has been proven
to work exceptionally well together.”
Lundin said Saab’s new technologies and systems are
highly automated, so crew size has been kept small.
The original Klewang-class trimaran prototype was launched
in August 2012. However, an electrical fire close to the fuel
tanks soon after destroyed the hull. Future vessels will be
made of new carbon fiber laminates with vinyl-ester resin
that are very resistant to fire and self-extinguishing.