Why the World’s fastest superyacht (Baltic 111 Raven) has a speed limit

Crossing the Atlantic in under seven days on a foil-assisted superyacht marked the ultimate proof of a mind-boggling concept. The ultralight Baltic 111 Raven redefines amazing superyachts, argues Toby Hodges

On first glance, you might assume Raven is pure AI-generated fabrication. A fantastical superyacht with 7m canting foil arms? But the fact the majority of these photos show it scorching across the Atlantic to set a new monohull record for the RORC Transatlantic Race should help prove that this Baltic 111 is really very real. They also support my case for this being one of the most remarkable vessels ever built.

It’s a craft with the potential to sail so fast that it has to be limited, literally kept on a leash, restricted by the materials and technology of its day. “If you don’t stop the boat, it will break in two,” warn its designers. The concept revolves around achieving and respecting extreme speed.

Crucially, Raven is a superyacht, not a stripped-out supermaxi. And even if it wasn’t armed with those Transformer-like appendages sticking out of its sides, it would present a new level of performance superyacht cool, where statement Maxi meets Monaco glam.

That said, the sharp styling, from guest cockpit to interior furniture and finish, was executed despite spacecraft-levels of lightweight construction. Achieving this foiling performance required the design and project team to create a yacht around half the weight of most conventional carbon superyachts.

Let’s consider that 6-day 22-hour crossing. It’s half the time it took larger competitors, including Swan’s new flagship 128 and the Truly Classic 128, and it clips Comanche’s record, a yacht considered to be the fastest offshore racing monohull.

Raven sailed at sustained speeds above 25 knots and at less than 10° heel – more comparable to a multihull.

Such stately heel angles are thanks to those foils. While canting foil arms like these were first conceived back in 2017 to make the America’s Cup AC75s fly, Raven’s are used more like giant stabilisers. The leeward foil produces phenomenal righting moment, supporting up to 60% of Raven’s displacement, and allowing the yacht to keep going faster without leaning over.

Post-launch, it took Raven’s crew of elite maxi sailors and technicians two and a half years to gear up this complex weapon, testing and optimising it over 17,000 Atlantic miles, before they were ready to take on this RORC Transatlantic Race record challenge.

Speaking with the design and project team at length was fascinating, not least to discover how, when you break new ground, you have to set safety parameters for the yacht’s structures and those sailing aboard.

“We know the boat’s fast, it’s just a matter of keeping it in one piece,” commented sailing master Brad Jackson on completing the record crossing.

Free thinkers

The pursuit of such extreme parameters takes vision. The craft is the product of many eminent design and engineering minds, especially the overall concept from virtuoso Finn Jarkko Jämsén. The founder of an award-winning Finnish design company is credited with the much-imitated lines of the Axopar powerboat range.

After working with Raven’s owner for many years, he explained how his brief crystallised into a superyacht that was to be faster than any racing yacht – no small task!
Jämsén studied canting keels and other technologies, but knowing they had a speed ceiling he put a tender out to five naval architects. Spanish firm Botin & Partners answered that call in 2020, at a time when they were working on the NYYC American Magic design for AC36. With a prototype foiling in Newport, Botin knew the lifting foil concept worked.

Super cruiser

“We presented that straight away, and they said yes,” explains partner Adolfo Carrau. “But the idea was never to make the boat a foiling boat… the appeal of the project was that it had to be a super cruiser, the equivalent of a Ferrari or a McLaren.”
Carrau explained that because the design doesn’t foil, it was a high-risk undertaking. “The dynamic righting moment once the boat starts to pick up speed keeps increasing, and there’s no limit, really, the limit is structural. If you don’t stop the boat, it will break in two,” he cautioned.

Meeting the owner really helped the design team, as he understood these risks involved. “We had to pick a maximum righting moment we were all comfortable working with,” Carrau continues. “So, once we defined that, we had to work backwards. What was the top speed that we’re going to allow the boat to sail to? And that was around 33-34 knots.”

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The challenge became how to create an offshore speedster with record-breaking potential, yet one that is also a superyacht that could be sailed for fun and incorporates a proper interior. Even if a fully foiling boat were structurally possible, the keel would have to be sacrificed to reduce enough weight without stripping the interior.

Raven required the inherent stability to be a performance superyacht even if the foils were disabled or removed. “If something goes wrong and we don’t have a secondary stability system in there that would be too heavy a penalty to carry,” thinks Jämsén. “So that’s why we went for skimming because it’s still fast, but if something happens, it’s still just a normal boat.” A combination of significant form stability, a low bulbed keel and 10-tonnes water ballast ensures this inherent stability.

Safety was a paramount concern, but a big question was how to make it light enough yet still safe. “We basically break a rule by having a smaller bulb, but then we have infinite righting moment from the body [hull],” Jämsén divulges. “So when we start speeding up, we just build up the righting moment, constantly bigger and bigger.

“Raven is a boat that if you let it go, you break the boat. Because it just wants to go faster, so it’s more a question of controlling that.”

Such pace prospects would bode well for its brief, which Jämsén says was “to be the fastest, and to have a proper chance to break records”. From here, they could build a ‘platform’, a versatile yacht that can be optimised over time and given an afterlife. In this way, Raven has a deck-stepped mast that can be replaced, perhaps by a wing mast in time; the rudder stocks are designed to be able to accept T-foils; and the foils are attached in the hinge points to allow different types of foil arms.

Above all, this platform needed to be built on a new scale of lightweight.

The build challenge

The ambitious aim was to take a massive 50% out of the weight of a comparably-sized performance superyacht. Target displacement was set at 55 tonnes (as a comparison, the 110ft Baltic carbon performance cruiser Zemi built at a similar time weighs 95 tonnes). Despite pitching it to four yards, Jämsén remarks, “Baltic was the only yard that was willing to make the boat – massive hats off to them for that kind of boldness and trust.”

Baltic’s project co-ordinator, Mattias Svenlin, confirms it was “another level entirely in terms of weight saving.” He describes the many challenges and how these forced the Finnish yard to review all its standard ways of building. The team even constructed an entire 1:1 mock-up, then the full mould in carbon fibre.

“One of the biggest weight savings compared to the theoretical weight was probably the surface treatment of the hull and deck,” Svenlin tells me. The bold decision to invest in a 111ft carbon fibre hull mould ensured the simultaneous expansion of the mould and the optimised carbon fibre skin during curing. Baltic worked with and challenged the paint manufacturer to review sequences, thicknesses, and required paint quantities, which halved the weight per m2. “Achieving superyacht quality on all painted surfaces while reducing the weight by around 400kg is pure boatbuilding joy,” exclaims Svenlin.

Raven’s construction took nearly two and a half years, during which the weight of every fitting was scrutinised, down to 3D-printing the titanium head of the retractable propulsion system.

Customising every part to save weight like this also necessitates thorough testing to ensure it is safe and will work. Raven uses a diesel-electric hybrid system comprising a 130kW electric motor, retractable propeller with carbon blades, and twin 80kW Yanmar generators to charge twin battery banks.

“We made a custom propulsion line because then we don’t need to have a gearbox, so have a hybrid system that is lighter than conventional,” Jämsén explains.

The battery bank is in a bespoke steel enclosure for which the team conducted their own fireproof tests. Creative styling helps celebrate this new level of weight obsession. Jämsén wanted to expose the structures as much as possible – even the coloured wiring looms and ballast tank transfer pipes are deliberately visible.

Since Raven’s autumn 2023 launch, the team has invested more time in finding extra weight savings. Such a complex machine takes time to understand. Team manager Klabbe Nylöf says that during their first year afloat, which they largely spent getting it ready for the owner to sail safely, they discovered more of her performance potential.

“Stage two of the boat’s life has been focusing a lot on performance,” Nylöf explains. This included removing the owner’s berth as he realised he wouldn’t sleep on that in race mode. The design anticipated some of these alterations. “We’ve stripped out 5-10% of the weight – when you start racing, you destroy those kinds of things [beds, sofas etc]. All the static things like galley, toilet are exactly the same.”

Raven in flight

Raven spent most of its first two years based in the Canary Islands, using the Atlantic for testing grounds. This was a critical period, one in which Nylöf emphasises the project could have stalled in other hands – it needed the right specialist team (and owner to keep investing), to ensure the design and build potential was fully realised. He also points out that they had no structural issues.

Under sail, Raven looks otherworldly, where beauty meets the beast, an aquatic predator sporting ungainly wings. In terms of motion at sea, Nylöf says there’s no disguising the fact that it’s still a big, voluminous yacht.

He says its not like Comanche, which has low freeboard, instead, Raven’s additional volume adds to the impression that you are “completely sending it offshore… but a 111ft yacht that doesn’t heel that much, means you get fooled sometimes that you’re not doing that high speed.”

The crew found that the foil also dampens the motion through waves. It’s still noisy and uncomfortable, and pipe cots are necessary at sea, Nylöf continues. “But once the boat starts accelerating and the foils are working well, with zero resistance, you get that breathtaking acceleration – actually very similar to a multihull, it feels like it just doesn’t want to stop, it just continues to speed up. That’s a fantastic feeling.”

This acceleration quality was a factor celebrated on reaching Antigua. Skipper Damien Durchon likens it to the swiftest ocean-going yacht, the MOD70, and praises its stability: “The interesting thing is that the better it performs, the safer it becomes. At speed, the sensations are incredible. At 25 knots it already feels fast, but once you’re above 30 knots you’re moving quicker than the waves themselves.”

To generate the power aloft for this pace, Raven employs a more typical supermaxi sail package. A Southern Spars carbon mast carries Helix structured luff sails from North, while the 8m bowsprit encourages a triple-headed sailplan. Trimming these sails is more comparable to a racing multihull, as the apparent wind angle is nearly always well forward, while depowering the main is via a traveller which spans most of the 7.4m beam.

The real science is in controlling those foils and trimming their flaps to provide optimum lift when offshore. Designed to lean onto her pronounced leeward chine, Raven’s stern stays immersed, while the canting side arms are operated via hydraulic rams to control the T-shaped foils and produce the dynamic lift.

“We found with the current foils, we were able to lift 50% of the boat’s displacement, or 25 tonnes,” Botin’s Carrau explains, “already a huge number unseen on any boat that we know of. Because you’re lifting the hull, you’re reducing wetted surface, and that’s where the speed comes from. Plus, it’s coming from leeward, so you’re getting positive righting moment. So it’s a virtuous cycle happening there.”

Comfort at speed

The canted angle of the immersed foil is trimmed to the sail angle, while the foil’s flap angle is adjusted to suit the desired heel angle. “So, you just put more flap, and the boat gets more upright and more bow up, and so it’s actually way more comfortable,” Carrau continues. “They’re not power reaching at 28° of heel, they’re really heeling at 8° to 10° and bow-up so they can really push as hard as they want.”

Learning how best to use and trim the foils and developing the programme to control them became the team’s highest priority. Their flight control system takes heel, pitch and wind input, but it is a continuous job to get it working properly, Nylöf explains. “It has taken us 18-20,000 miles to get a programme where the boat can handle itself.”

Two engineers are on rotation full-time to ensure these systems are working and feeding the correct information.

The foil trimmer is a dedicated role, much like the mainsheet trimmer. “The more load on the mainsheet, the more flaps you need to stop it heeling over, then the boat accelerates, and you need less flap,” adds Nylöf.

“It’s the first boat in the world that we are aware of that has the dynamic righting moment live in the display,” Carrau adds. “So they keep trimming and closing the apparent until they’re close to the maximum righting moment. And that’s where we feel this acceleration, because that’s when the boat starts lifting and off you go.”

The challenge is then knowing when to back off – “sometimes in the ocean in the middle of the night, surfing a wave, you just cannot stop the boat. So that’s part of the learning curve, and that’s why the boat has big safety margins.” Carrau points out the conflict here, as sailors inherently want to go faster. But once Raven is really up and humming, you have to unload the sailplan and let her sit at that 30-knot area, where it will maintain such speed comfortably without activating the alarms.

“It’s a different type of sailing – there’s no boat like that in the world.”

During their extensive testing phase, the Raven team also worked closely with the Wolfson Unit in Southampton to help it meet RORC’s stability criteria. “They had to create regulations for semi-foiling boats that didn’t exist,” Carrau explains. Getting accepted onto an offshore race and then succeeding is not only a proof of concept, but it changes the mentality around this technology, he believes.

More records to break?

With Raven’s structural and stability requirements quantified, is the vessel now poised for more record-breaking? “It wasn’t about building a Comanche-beating boat,” maintains veteran navigator Will Oxley, speaking on the Yacht Racing Life podcast. “This is the first foil-assisted boat like this that has done the Atlantic, and this was our third crossing. The more miles we did, the more interest the owner had in going fast.”

Oxley predicts Raven can clock 600-mile days – “meanwhile, it’s more comfortable than anything else I’ve sailed”. As well as the significantly reduced angle of heel, this comfort factor comes from not flying and its associated crashes. “When the foils stall, she sails like a normal boat,” Nylöf confirms.

Broad reaching is the zone where Raven is perhaps unbeatable – ocean drag racing then. Stable tradewinds during the RORC Transatlantic helped it really spread its wings, although it required plenty of gybing. The compromise with these foils and huge furling headsails, is that the boat isn’t optimised for VMG racing, particularly upwind or full downwind sailing.

The design team is now trying to find more speed in lighter winds. “There’s a lot of performance yet to be untapped if the owner wants to keep going. Mind you, they cannot go any faster,” Carrau cautions. But they can keep optimising the boat so they arrive at those 30+ knot speeds earlier.

Following a rest period to allow non-destructive testing ashore in the US, the team may attempt the west-to-east Atlantic record. While this is for manually-powered yachts – which Carrau concedes Raven will never conform to – “at least unofficially, it’s an interesting one, because when they’re going 130° or 135° true, the boat is probably unmatched right now. It’s very, very fast.”

Nylöf broadens this ‘sweet spot’, adding that in 20-28 knots of wind from 90-135°, “she’s astonishingly fast.” If the owner chooses to keep spending money, the upgrades could keep adding pace at wider angles. Consider the amount of foil development alone in the five years since hers were designed. Jämsén says they anticipated such revisions at design stage, creating a titanium ankle so they can adjust the overall foil angle. Raven is a tunable instrument, a platform, he reminds us.

“And when it retires from breaking records or having fun in the open ocean, Raven also has a second life – then it can be that fast, super nice boat,” Jämsén quips. “Raven is a one-off super-product.”

Baltic 111 Raven specifications

LOA: 34.00m / 111ft 6in
DWL: 33.10m / 108ft 7in
Beam: 7.40m / 24ft 2in
Draft: 4.80m / 15ft 8in
Displacement: (lightship) 55 tonnes
Ballast: 9,300kg / 20,500lb
Design: Jarkko Jämsén; Botin Partners

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