Fuente info Baltic Yachts
BALTIC 111 RAVEN IN A CLASS OF HER OWN AS SHE IS PREPARED FOR LAUNCHING
10 July 2023
When her owner commissioned this Baltic 111 Custom foil-assisted superyacht, weight control was paramount. Baltic Yachts was selected for its forensic approach to lightweight advanced composite construction and unique ability to combine it with an unmatched custom finish
Baltic Yachts has successfully moved the Baltic 111 Raven from her building facility at the company’s waterside premises in Jakobstad, Finland to reveal one of the most extreme yachts it has ever built.
Broadly described as a 111ft foil-assisted, ultra-lightweight superyacht, she will be used primarily for day sailing, but also undertake high-speed, long-distance passages. Not easy to categorise, this extraordinary yacht can be placed firmly in a class of her own.
Baltic Yachts was chosen to meet this challenge because of its unmatched reputation for building advanced composite superyachts to the very highest standards, including its forensic examination of systems and components throughout the build process. Add to that the company’s ability to finish yachts to a level of luxury second to none and the decision to build in Jakobstad was straightforward.
Raven’s experienced owner’s project manager, Garth Brewer of A2B Marine Projects, said: “Raven doesn’t fall easily into a category, but if I had to place her, I’d say she’s the equivalent of a high-end Super-car. The boat is primarily for pure enjoyment and the owner likes the challenge of doing something that hasn’t been done before.”
“He really understands the technical elements and this will be a development project which will require a measured approach,” added Brewer, who emphasised the need for incremental steps in Raven’s trials, building confidence and understanding over time as the boat reaches her peak performance.
Hydrofoils
Raven does, however, possess some distinctive features which provide more than a hint of how she might perform. They include two large T-shaped hydrofoils mounted on hydraulically controlled side-arms capable of supporting some of the boat’s displacement.
At her transom, Raven will be equipped with vertical Interceptor trim tabs to adjust fore and aft trim at speed and there is movable water ballast, carried in built-in tanks in the aft quarters to boost the righting moment required while sailing.
Designed to sail partly on her leeward chine, Raven will derive her stability and lift, while sailing, from her foils, leaving her 9.3-ton fixed keel bulb and precision-engineered 5m long fin to provide basic stability. It’s also the location for a fully submerged intake for cooling water and is designed with a sacrificial zone to absorb impact in the event of a collision.
Ultra-lightweight interior
Not only is Raven’s foil-assisted ability likely to deliver a phenomenal sailing performance, she is also the subject of a highly unusual study in ultra-lightweight interior design, combining the yacht’s complex all carbon construction with styling which pays homage to Baltic Yachts’ rigorous programme of weight saving. Target displacement is 55 tons – just as a comparison, the recently launched, Baltic 110 Zemi displaces 95 tons.
Jarkko Jämsén, the Finnish concept designer who developed Raven with her owner and is responsible for the yacht’s extraordinary styling, explained that they were keen to combine the need for weight saving with the opportunity to expose the remarkable carbon structure of the yacht to create a unique interior design aesthetic.
Normally, part of a superyacht’s accommodation might be mocked-up to make every effort to get the detail right, but in Raven’s case the entire boat was checked out in a 1:1 mock-up
A key part of Baltic’s effort in the Raven project has been directed at weight saving and control. Apart from using the lightest possible carbon/Nomex combinations in the yacht’s main structures, every item, down to the last pipe clip, nut and bolt, has been assessed. The naval architects and structural engineers behind her are Botin Partners and PURE Design respectively, both at the leading edge of America’s Cup design.
“This project undoubtedly represents one of the biggest challenges Baltic Yachts has ever embraced,” said Baltic Yachts Executive Vice President, Henry Hawkins. “But that is what we do – we have a long history of bringing leading edge innovation to the fore. We are surrounded and supported by a dedicated team who are led by Garth Brewer, who oversaw Visione’s construction here at Baltic 21 years ago and still keeps her on the pace.”
Experience to take on the challenge
Jarkko Jämsén emphasised the importance of choosing Baltic Yachts to build Raven. “The company was selected because we believe it has the courage, experience and track record to take on the challenge. Calculating weight and Baltic’s well-known ability to hit displacement targets were critical.”
Baltic Yachts was chosen for its proven ability to build to the finest tolerances using carbon composites and in Raven’s case much of the immaculate hull and deck structure will be exposed as part of the interior styling and décor
For Sam Evans, project manager, and Mattias Svenlin, project co-ordinator for Raven, the challenge was to construct a superyacht much lighter than anything previously built by Baltic – yachts that were already considered light in the sphere of Superyachting. “Mattias’ experience, creativity and flexibility, supported by a dedicated production team combined with Sam’s communication skills, have been key factors in the overall success of the build,” added Garth Brewer.
Taking weight saving to another level
“This is another level entirely in terms of weight saving,” said Mattias. To ensure as fair a hull finish as possible, a carbon mould was preferred to reduce excessive heat differences and thus distortion in the curing process. “We re-assessed the hull coating schedule to reduce weight using light primers and filler instead of Ultra-Build to reach the acceptable industry standards – in effect coatings do the job of filler,” he said. Using this technique in a superyacht is unprecedented.
The shape of Raven’s hull and deck were created by a precision engineered wooden ‘tool’ from which carbon moulds were created, in turn producing the split hull and deck components. Unusually the moulds were made in carbon to eliminate heat differentials, distortion and reduce fairing to an absolute minimum
The all carbon/Nomex hull being prepared for coating. Note the pronounced chine and side arm apertures indicating the position of the hydraulically operated, T-shaped hydrofoils. There’s less than a metre difference between the yacht’s hull length and waterline length
Hull and deck construction use carbon IM fibre pre-preg, employing the highest quality fibres on the market, and a Kevlar honeycomb sandwich throughout. The owner has accepted that sailing Raven at speed will be noisy so the elimination of any attempt to sound deaden represents a huge weight saving. “But we have created an interior finish with special surfaces affecting the acoustics to ‘soften’ the noise a little,” said Mattias. He pointed out, however, that all the adhesives suitable for bonding this material to bulkheads were compared for weight, the final choice resulting in a saving of 6kg. In terms of the Raven project that’s a big number.
To reduce weight, almost no sound deadening material has been used, although a lightweight foam acoustic material has been applied to some bulkheads to take the edge of what will be a noisy yacht when she is sailing at speed. Carbon tubular frameworks and ratan are used extensively for deck head ‘panelling’ and furniture structures
100 grams off every bracket
Baltic Yachts has revisited all weight saving opportunities shaving 100 grams off every carbon pipe bracket, making carbon cable trays even lighter and switching out steel hydraulic pipework for lighter hosing which has saved 160kg. “We’ve even reduced the weight of the shower door from 13.5kg per m² to just 2.3kg m²,” said Mattias.
Even as Raven neared completion, the Baltic build team were continuing to identify weight saving opportunities including replacing the metal clips holding the lightweight carbon tubular accommodation framework in place. “Östen Sundelin, one of the team, reckoned we could 3D print them in a far lighter material so we went ahead and made that saving,” said Mattias. In-house 3D printing is increasingly used at Baltic to fashion custom items to save weight and optimise design, the complex titanium head of the yacht’s retractable propulsion system (RPS) mechanism being a case in point.
Study in lightweight interior design
Raven’s interior, conceptualised by Jarkko Jämsén, is unusually comprehensive for a high-performance superyacht of this type, but the use of ultra-lightweight rattan deck-heads and bulkhead finishes, exposed carbon and a lack of coatings helps keep weight down along with Nomex cores in structural bulkheads. All the frameworks for the furniture, for example, are made from hollow carbon piping, its light weight combining with a modern take on style guaranteed to turn heads.
Lightweight, but stunningly stylish, part of the forward saloon area with its carbon custom control centre seat, lightweight ratan deck heads and a glimpse of the ‘bird’s nest’ cockpit structure, top right
The focal point of the accommodation is centred around the glazed sides of the large cockpit, dubbed the ‘bird’s nest’, which forms a type of inverted observation ‘dome’ allowing occupants to view the carbon dominated accommodation. The glazing is in fact Perspex, which is considerably lighter than toughened glass, representing an overall saving of 250kg. It is reinforced with a criss-cross pattern of carbon mullions which gave it its bird’s nest description. Further weight saving is achieved by minimising the amount of caulking between each pane replacing some of it with a foam fillet.
On deck, attention is immediately drawn to the cockpit because, apart from its aforementioned aesthetics, it also converts to a semi-covered, hardtop protected seating area. The forward section of the cockpit hinges up and aft in ‘clam-shell’ style to affect this unique conversion.
Perspex is also used in numerous deck prisms which still use a centuries old design to efficiently illuminate the accommodation with natural light, but are vastly lighter by replacing bronze and glass with carbon and Perspex.
Raven’s dramatic bird’s nest cockpit structure forms a unique two-way observation ‘dome’. It is constructed of carbon composite mullions hand painted by a local artisan in Jakobstad to resemble timber. Glazing will be Perspex set in a lightweight caulking composite
Spacious saloons are located fore and aft of the bird’s nest, the forward one laid out with a galley and dining areas and the aft space dedicated to the owner’s sleeping accommodation, with a large double centreline berth folding up against an interior bulkhead when the yacht is in performance mode. There’s also a passage berth or sea cabin to starboard.
It is not often one can describe a head and shower compartment as a work of art, but in Raven’s case numerous hydraulic rams mounted inside some of the complex carbon reinforcement, including the A frame taking the load of the deck stepped mast, have been exposed by inserting Perspex inspection covers. So, you can take a shower while watching the upper and lower deflector rams in action or the downhaul ram for the 7m long reaching strut, which is used to optimise headsail sheet leads!
Further weight saving has been achieved by modifying a custom bamboo seat in one of the shower/head compartments with carbon tubing made to look like bamboo, complete with its characteristic rings and a remarkably realistic painted finish.
Bamboo, but not as we know it. To reduce weight even further and resist splitting, the ‘bamboo’ used to construct an unusual seat in the shower compartment is, in fact, carbon moulded and painted to look like the real thing
The aft section of the yacht is largely empty, but forward there’s accommodation for four guests in two cabins and extensive crew accommodation including a captain’s cabin.
Powering Raven
For propulsion and generating, the design team settled on a diesel electric hybrid system for lower emissions and efficient weight distribution. It’s a solution Baltic Yachts has been perfecting for a number of years. A Swiss 130kW Phi-Power AG electric propulsion motor is located just aft of amidships and twin 80kW Yanmar generators, optimised to save weight, located further aft. These charge two battery banks which power the main propulsion motor, hydraulic pumps and accommodation services. The drive train is completed by a retractable propeller designed with carbon blades and a titanium hub.
Stand by for performance!
Her rig and sailplan are relatively conventional for a performance maxi, with a Southern Spars carbon spar and a North Sails 3Di upwind wardrobe using Helix structured luff technology. A variety of Code and asymmetric sails can be set off her 8m long bowsprit.
Something Raven’s design engineers and Baltic had to pay particular attention to was the yacht’s almost full beam mainsail sheet track. Because Raven will be developing so much apparent wind, she’ll be sailing most of the time with a wind angle well forward of the beam. So, like a multihull, the main is likely to be almost permanently sheeted home while trim adjustments are made by moving the mainsheet car along its track.
With a beam of over 7.4m and her accentuated hull chine, ‘driving’ Raven will feel more like sailing a multihull than a monohull and appropriate trimming and handling techniques will be needed to extract her full potential.
Initial trials off Jakobstad will see Raven sailing minus her foils. These will then be fitted, further trials in Finland will take place and following delivery she will leave for a destination providing the conditions in which she can be worked up steadily as her potential is realised.
It’s going to take time for Raven to seriously spread her wings, but when that moment comes it will have been worth waiting for – stand by for performance!
DIMENSIONS
LOA 34.00 m
DWL 33.10 m
Beam 7.40 m
Draft 4.80 m
Displacement 55 tons (light craft)
Ballast 9300kg
CONCEPT, DESIGN AND BUILD TEAM
Concept: Jarkko Jämsén
Naval architect: Botin Partners
Exterior and interior design: Jarkko Jämsén
Structural Engineering: PURE Design and Engineering
Owner’s project manager: Garth Brewer, A2B Marine Projects
Manager Raven Sailing team: Klabbe Nylöf
Baltic Yachts Project Management: Sam Evans, Mattias Svenlin
