Artnautica 60 - custom all carbon Sportfisher launched by Lloyd Stevenson Boatbuilders

by Robert Daly, Lloyd Stevenson Boatbuilders 18 May 2023 16:47 NZST 16 May 2023

Lloyd Stevenson Boatbuilders have launched Matuku, a custom-built Artnautica 60 (18m) Sportfisher motor yacht. From the pen of Auckland-based designer Dennis Harjamaa of Artnautica Yacht Design, this striking boat was built for a New Zealand client.

The client set a challenging design brief as this boat had to fulfil three competing design objectives. First, a stable and efficient high-speed planing monohull; set up for offshore game fishing. Second, a spacious and comfortable family cruiser. Third, an efficient, long-distance passage maker, with a range of more than 1,200 nautical miles – the distance from New Zealand to Fiji, without the need to carry reserve tanks.

“I was tasked with designing an 18m planing hull able to foot it at a decent clip, but which would also be efficient at displacement speeds,” says Dennis.

“And it had to be able to go far – very far – in bluewater conditions. That all boiled down to a slippery hull with smallish engines for the extended range. It also meant a light but very strong construction. I initially thought standard, foam-core would work, but as the design progressed into structural engineering and costings, it soon became clear that carbon fibre was the only way we’d achieve the required strength and performance. A lightweight hull, plus smaller engines, leads to a virtuous circle of less mass and less fuel consumption.”

So Dennis opted for twin Volvo IPS 800 (625hp) engines. But given the uniqueness of this boat, getting Volvo’s permission to use the IPS system required some discussion. “Volvo is very particular about its IPS installations,” says Dennis, “and that’s understandable – the IPS reputation is on the line. Because of the unusual carbon construction, they wanted to check the design. We submitted drawings and calculations – and ended up with three data sets in the mix.

“I gave my initial calculations to a CFD (Computational Fluid Dynamics) specialist for checking and followed that with results from virtual tank testing. These were compared with Volvo’s calculations. Happily, we arrived at a consensus.”

The lightweight hull and IPS 800s have worked precisely as Dennis had envisioned. Matuku cruises at 23-24 knots, using around 155 litres (41 U.S. gallons) per hour.

Push the throttles wide open, and you are at 32 knots in the blink of an eye, yet the desired fuel efficiency has been achieved.

For passage making to Fiji and other Pacific islands, an 8-10 knot cruise speed will be employed, giving a range of 2,000 to 2,400 nautical miles.

Designed to Hunt

The Artnautica 60 is a true custom build. Unquestionably designed to hunt, as evident by the Kilwell outriggers, Matuku is built more like a racing sail yacht than a traditionally built sport fisher, with every component weighed after fabrication before installation. Lloyd Stevenson Boatbuilders’ experience producing high-end, full custom, carbon composite superyacht tenders reassured Dennis Harjamaa that they were the right builder for the job.

Matuku’s owner was intimately involved in her design and construction, enjoying the flexibility a full custom build allows, and quickly developed a great relationship with the team at Lloyd Stevenson Boatbuilders; “I liked their work, their approach and I liked the people. And they accommodated me – I visited the factory for an hour or two most weeks over the entire build process.”

When asked what the build experience has been like, project team leader Gareth Curd said, ‘It has been awesome to have our client involved every step of the way. This has totally played into our strengths as custom boat builders; it means we have been able to include many of the small design changes and personal touches our client wanted as we have gone along.’

‘It has been a very interesting boat to build.’ Project manager Kerry Johnson added, ‘It’s been great working with an owner who appreciates engineering effort and workmanship behind the scenes.’

Large interior volume

Keeping things light, however, has not required sacrificing comfort; Dennis’ plumb bow allows the interior volume to be carried all the way forward, allowing the owner’s cabin to include a super-king bed. The other two cabins, a double and twin bunk respectively, both share the guest head.

All the living spaces are finished to Lloyd Stevenson Boatbuilders’ usual, very high standard, with the interior cabinetry in white oak veneer over a foam core - more weight-saving.

The large, panoramic windows in the saloon and galley offer excellent views. The sight lines are kept purposefully low, ensuring a view can be had from any seating position – a requirement from the “family cruising” aspect of the brief.

The saloon, galley and cockpit floors are covered with Flexiteek; given the pelagic pursuits that Matuku will undertake, this is a practical solution while still maintaining an attractive level of finish.

Sport fishing design features

Matuku’s sophisticated infrastructure is orchestrated by CZone and includes an extensive inventory for finding prey with three transducers linked to six Furuno TZT3 MFDs - three 16” units at the helm, another two on the flybridge and a 19” unit in the cockpit.

The transducers are a 3kW Airmar R509, a Furuno DFF 3D multi-beam unit (120°) and a 600-watt Airmar forward-looking unit (“so that you can see what’s ahead of you rather than what you’ve just hit”).

The Furuno 3D transducer is set up for PBG (Personal Bathymetric Generated) mapping. It can generate up to 50 depth points per second, quickly creating highly accurate 3D maps and recordings of the ocean floor and then integrating the data with existing charts. The Furuno system, according to the owner, is also particularly good at monitoring weather forecasts and sea temperatures – important considerations when you’re a long way offshore, looking for game fish.

The ability to map and record the seafloor has been extended to the 3.5m Williams jet tender (stored on the flybridge). “It’s our exploration boat,” says the owner. “It’s fitted with the same Furuno sounder as the one on the mothership and wirelessly relays its seafloor soundings to the main MFDs. It’s useful when fishing shallow and poorly charted areas or when entering remote bays and anchorages.”

The transom is dominated by a 250-litre (68 U.S. gallon) live bait tank flanked by four tuna tubes (two on either side) hidden under Flexiteek hatches in the gunwale; when active, overflow water is captured by dedicated channels around the lip and drained overboard, rather than spilling into the cockpit.

Their construction and design are yet another example of the attention to detail evident throughout the entire boat.

Another example of this is the aforementioned Furuno 19” MFD. This is recessed into the ceiling over the cockpit’s outdoor lounge. Mounted on a button-actuated, flip-down bracket, the screen swivels 180°, providing aft-facing anglers seated in the cockpit lounge a view of aquatic life. Swivel it 180° and the skipper can position the vessel precisely over a sea mount using the remote helm joystick.

Like the tuna tubes, the remote helm joystick is hidden under a hatch in the port gunwale, and, at the push of a button, it is lifted into position. Very useful when the fight is on and a hasty backup is required. And rather than the usual shouted, expletive-laden exchanges, calm and civil instructions can be shared.

As you would expect of a fishing machine of this calibre, Matuku is fully equipped with a saltwater icemaker, a vacuum-packing machine – and a large freezer. All located in a massive midship machinery room, yet another advantage of utilizing the IPS system.

The Machinery Room:

Using the IPS drives means the engines are located well aft, leaving a large space where a shaft-driven vessel’s engine room would typically be. Dennis took advantage of this and has put it to good use. Immaculately finished; in addition to the freezer, saltwater icemaker, etc, there is also a 400 litres/hr watermaker, a dive compressor (and six tanks), the Webasto air-conditioning unit, a Post diesel water-heater, two 20kW Fischer Panda gensets, the main engine fuel polishers, a 5,500-watt Mastervolt lithium-ion battery bank. And, of course, lots of storage space. In addition to the gensets, a pair of Victron Quattro inverters are installed to run the 24-volt system, allowing the vessel to run silently at night.

Flybridge views:

Very much influenced by the owner’s wants, this minimalist cantilever design offers spectacular, unobstructed views. “I prefer clean, open aesthetics,” says the owner, “and anyway, in miserable weather we’ll go downstairs.”

The flybridge helm station is joystick controlled and includes two 16” MFDs. Matuku responds effortlessly with the IPS technology eliminating the need for bow and stern thrusters, spinning in her own length with ease.

Finished to LSB's usual exacting standards, we are immensely proud of Matuku and welcome her to the LSB family. If you are ready to build a sportfisher of your own and enjoy sea trialling it in some of the best game fishing grounds in the world, please contact Matuku ("Ma-too-koo")

Aptly named, Matuku (Egretta novaehollandiae) is the Maori name for the white-faced heron, a fishing bird that patiently watches for any signs of prey, which it grabs with lightning speed.

Specifications:

• LOA: 18m
• Beam: 5.6m
• Draft: 1.27m
• Design: Artnautica Yacht Design
• Builder: Lloyd Stevenson Boatbuilders, Auckland, New Zealand
• Construction: 100% resin-infused carbon fibre
• Displacement Dry: 22 tonnes
• Diesel: 6,000 litres (1,585 U.S. gallons)
• Water: 1,000 litres (264 U.S. gallons)
• Power: 2 x Volvo Penta D11 IPS 800 at 625 hp each
• WOT: 32 knots
• Cruise Speed: 26 knots

Fuel Consumption:

• Sea trial conducted by Volvo Penta with 4,000 lt of fuel (1,506 gals), 900 lt (237 gals) of water and no trim.
• Trolling Speed (8 knots) 20 litres per hour combined (2.5 litres/nm) Range 2,400nm
• Passage making (10 knots) 30 litres per hour combined (3 litres/nm) Range 2,000nm
• Cruise Speed (24 knots) 155 litres per hour combined (6.5 litres/nm) Range 923nm
• WOT (32 knots) 244 litres per hour combined (7 litres/nm) Range 850nm

About Lloyd Stevenson Boatbuilders:

In 1985 Lloyd built his first boat, a Davidson 42 yacht named Teddy Bear.

Over the next thirty-seven years, with Lloyd’s relentless drive to achieve excellence, the team at Lloyd Stevenson Boatbuilders has built an enviable reputation for quality and fine craftsmanship, amassing an impressive portfolio of bespoke boats of the highest quality for both New Zealand and international clients.

From private motor yachts to carbon fibre race yachts, cutting-edge custom superyacht tenders, and chase boats for America’s Cup challenger teams, our in-house experience allows us to undertake the most complex of projects.

With our purpose-built factory in East Tamaki, LSB prides itself on adopting new construction technologies whilst retaining the ethos and quality of traditional boat building.

And the best thing about building a boat with Lloyd Stevenson Boatbuilders - you can sea trial in some of the most beautiful and bountiful waters in the world.

For more information or further queries, please get in touch with Robert Daly at