On a summer weekend there’s always a bustle of activity on the foreshore at Hamble-le-Rice, on England’s south coast. The whirr of electric air compressors has been the soundtrack to the rise and rise of the inflatable paddleboard. And it may be about to initiate another transformation, simplifying sailing to the point where it returns to its birthplace; commercial shipping.

Matt Sheahan reviewed the Inflatable Wing Sail (IWS) for Yachting World more than three years ago and was impressed by the invention of Edouard Kessi and Laurent de Kalbermatten. Based on an unstayed, telescopic mast, the IWS inflates via an integrated air compressor to a surprisingly low pressure, just two millibars.

It creates a soft, symmetric wingsail with many of the efficiency advantages of a hard wingsail (amply demonstrated in America’s Cup and SailGP racing) but none of the problems – it’s very simple to raise and lower, and just disappears down to the deck when you don’t need it. Matt predicted that the much-simplified handling could mean a significant future for the IWS in superyachts and commercial shipping.

Simplifying the way that sailboat rigs work is far from a new idea. The IWS follows in the wake of many of these initiatives with its unstayed mast, an idea that has its origins in the Chinese junk rig.

Gary Hoyt’s Freedom Yachts utilised this approach in the mid-1970s. Meanwhile in the 1980s, a building beside the very same River Hamble produced the AeroRig, a free-standing mast with a rotating boom on which both headsail and mainsail were set. The forces were easily balanced and controlled by the mainsheet alone.

A descendant of the AeroRig is the Dynarig, developed by Dykstra Naval Architects and built by Magma Structures in the UK for two spectacular superyachts, the Maltese Falcon and Black Pearl. A recent partnership agreement with Southern Spars means that the Dynarig will now be developed with the support of one of the marine world’s most sophisticated technology providers. The rig is targeted at the people who want to keep it simple, and this can include superyacht owners interested in reducing crew numbers and handling issues.

Dykstra has a Wind Assisted Shipping Project (WASP) in process, a multipurpose cargo ship which uses the Dynarig masts as cranes, and is working with Veer on the world’s first emissions free cargo fleet. The Dutch design house, responsible for some of the most iconic superyacht and J Class projects, also tells us that it is currently working on a couple of new classified Dynarig superyacht projects.

This is where most of the momentum is headed with these new technology rigs in the superyacht world. VPLP is perhaps the world’s most successful yacht design groups since Marc Van Peteghem and Vincent Lauriot Prévost set up their business in 1983.

They’ve won the Vendée Globe, the Jules Verne, the Route du Rhum, and in 2010 the America’s Cup with the huge wingsail on BMW Oracle. “Marc [Van Peteghem] saw the potential of that highly efficient automatable wingsail,” explained Simon Watin, president of their maritime division.

“He’s been at the forefront since that period, really pushing in parallel the maritime transportation and the yachting together,” continued Watin. VPLP started drawing the concept in 2016 and built the first Oceanwing to fit on a small trimaran. It’s an automated wingsail that hoists on an unstayed mast – similar to the IWS but using battens to create the wing’s shape, rather than inflation. It’s a two-element rig though, allowing for a more efficient foil and higher performance. VPLP built two 32m2 Oceanwings for Energy Observer, a former racing catamaran now circumnavigating as a technology platform. They also started to pitch eye-catching concept designs into the superyacht community.

“The people we are looking to convince are people that would normally go for a pure motor yacht,” explained Watin, “and who would not be so much interested in the sailing aspect itself.” Watin pointed to the gains in fuel economy, range, comfort and autonomy. The Seaffinity is a streamlined, concept trimaran from VPLP, “with a large main hull and two smaller floats featuring two Oceanwings, one behind the other,” explained Watin. “And this is really an illustration of a new superyacht that could have been a pure motor yacht, but actually benefits from the Oceanwing.”

Superyacht concepts

Another VPLP/Ayro collaboration has resulted in the radical Nemesis One superyacht concept, a 101m/332ft foiling catamaran capable of 50-knot speeds. The fully automated, push-button craft uses a modified Oceanwings wingsail which can furl and reef and automatically adjusts its angle of attack. There’s no question that this and the Seaffinity are striking vessels, and that the technology could make a significant dent in the operating carbon footprint of yachts that might otherwise have been engine-only.

The first large scale Oceanwing will be a commercial shipping project. The step came when VPLP and the shipping company Alizé successfully bid for Ariane Espace’s tender for a new concept ship that could carry parts of the Ariane 6 rocket from European ports to French Guiana. Once it had the contract, VPLP created Ayro as a separate business to develop the cargo ship Canopée. She is scheduled to launch in late 2022, at 121m long, and will be powered by four 363m² Oceanwings set on 36m masts. VPLP thinks the wingsails will reduce fuel consumption by 15% without compromising speed.

“The technical concept is aerodynamic efficiency with the solid sail with two elements: so reaching maximum lift coefficient. Automation; so no lines, no unnecessary human intervention for trimming, adjusting, hoisting. And much less impact on the deck plan, which is quite major, especially for a superyacht,” said Watin.

The difference in the physical and mechanical realisation of the Oceanwing for superyacht and commercial shipping markets is interesting. The version for merchant ships will stick to industrial suppliers as far as possible – electric actuators that would normally mobilise cranes, for instance. The wing will use a reinforced PVC fabric skin, the type of material that would make a truck tarpaulin.

The masts will remain in place in normal use, and the fabric wings will raise and lower on cables powered by electric rams, so the sail area can easily be reduced. A tilting mechanism will allow the mast height to be reduced for ports and bridges.

Unsurprisingly, the superyacht version will be a lot more sophisticated, but is still based on the same self-standing mast and 360° rotation of the sails. “We would use higher technology material, lighter fabrics as well… and for the yachts, we have to be more cautious about the weight of the installation itself, because the sail area is going to be quite a bit larger in comparison to the boat. And obviously, the design is going to be important so we will package all the actuators in a much nicer way – you don’t want a ram sticking out.”

Bold initiatives

Ayro is now responsible for all the design and engineering on the Oceanwing, with its own 35-strong design office, but VPLP remains involved. “Ayro has successfully raised quite a bit of funding to sustain its growth,” Watin told me.

It was 2019 when Matt Sheahan made his prediction for the future of the IWS in his Yachting World review, and three years later it appears that the commercial shipping development is also well ahead of the superyacht market.

The WISAMO system is an initiative from Michelin, with two-time Vendée Globe winner Michel Desjoyeaux associated with the project and testing. It’s the same concept as IWS, an inflated wingsail, set on an unstayed telescopic mast.

“When I discovered that system, I thought it has checked a lot of boxes compared to other systems,” said Desjoyeaux. “It has a plug and play system which is very easy to install and use, whether it is for a refit, meaning an addition to an existing boat, or for a newly built ship; you lower the mast into the boat, plug it in and off you go. Once you are out of the harbour, you push a button and the machine does everything. It unfurls the wingsail and automatically chooses the correct setting for cargo ships. This is crucial because there aren’t many crewmembers on the bridge, and they don’t necessarily know much about sailboats. They need a system that operates autonomously.”

At the beginning of 2022 Michelin announced a partnership deal with Compagnie Maritime Nantaise to test the WISAMO. The system will be fitted to one of their roll-on roll off vessels travelling between Bilbao in Spain and Poole in the UK. The plan is to have the ship in service by the end of this year. Meanwhile, tests with Michel Desjoyeaux’s own boat continued through last winter in the Bay of Biscay.

Michelin are claiming the system could save up to 20% on fuel costs. It’s in the same ballpark as the Oceanwing, and while it sounds good – particularly at today’s fuel prices – it’s actually only half of what the shipping industry needs to achieve by the end of the decade.

Reducing emissions

The shipping industry pumps out a lot of carbon dioxide – the most recent (2012) estimates being that shipping is responsible for 2.2% of global emissions. The International Maritime Organisation, an agency of the United Nations, has published a strategy for reducing carbon. Global shipping must achieve an average 40% reduction by 2030, increasing to 50% by 2050. The European Union is acting to give these targets legal force, and the first deadline is just eight years away. The task is immense, and the clock is ticking. That’s why the money and energy pushing these new sailing technologies forward is coming from commercial shipping.

One thing that’s been learned in the 150 years since sail last dominated the world’s oceans is that changing the world’s merchant shipping fleet takes time. In 1866, the year of the Great Tea Race, an auxiliary steamer left China eight days after the clipper ships and it arrived in London 15 days ahead of them. Steamships already had a significant speed advantage, but it was more than another 80 years before the last sailing ship ceased trading. This is the problem for the shipping industry; ships are built to last. The world once again needs to restock the entire global merchant fleet with a new technology, but this time there’s a deadline.

The same pressure is unlikely to be felt in the superyacht market for a while, and perhaps it never will. Still, once these new technologies have been developed and proven in the highly competitive shipping industry, it seems likely they’ll start to migrate to superyachts.

No easy options

There are many possible technical solutions but the easy changes – more efficient routing through weather systems for instance – will not get the industry to anything like the 40% required by 2030. The developments that will – new propulsion systems, fuel sources or hull designs – are still in development and/or will require massive capital investment. It’s taken a while, but the shipping industry has finally woken up to the scale and the timescale of the challenge it faces.

“They’ve got a massive problem on their hands,” said Simon Schofield, chief operating officer of BAR Technologies, a spin-off from the British America’s Cup team led by four-times Olympic gold medal winner, Ben Ainslie.

“In the last two years we’ve seen a marked difference in the industry. Two to three years ago when we were talking about this [wingsail] technology, people were like, ‘Yeah, it’s nice. People have been talking about this for years, but no one really wants sails…’ And now it’s, ‘How quickly can we have wings? What else have you got? We’ve got to move, we’ve got to get going.’”

Unsurprisingly, there is no shortage of people trying to solve this problem. The reward for developing any cost-effective way of reducing a significant chunk of those 40% of emissions will be a massive new business. The scale of the shipping industry is enormous, it’s a global business with a total value of more than US$14 trillion. So, there’s no shortage of ideas either, and kites were early leaders in this field.

The SkySail was a stand-out that got tested at full scale, installed in a custom-built ship, the MV Beluga Skysail, and tested on an Atlantic crossing in 2008 after 10 years of development. It fell at that hurdle, with the company turning instead to developing airborne wind energy systems for power production. The fate of the shipping project is sadly recorded on their website: ‘The SkySails propulsion system for vessels is currently not marketed any more.’ There’s no mistaking the significant risk in these ventures.

Fortunately, risks have never stopped people trying to innovate and there are plenty more projects with potential. The Flettner rotor is a tall, smooth cylinder mounted vertically, that rotates in the airflow passing the ship. It uses the Magnus Effect (the same thing that causes a spinning ball to curve in flight) to generate a force that helps to push the ship along. Norsepower have already installed a rotor on one tanker and it provided just over 8% fuel savings – good, but still nowhere near enough.

It’s now the wingsail that seems to be grabbing the bulk of the investment. A Swedish group, led by Wallenius Marine, has formed a joint venture with Swedish industrial company Alfa Laval to develop the Oceanbird, a wind-powered car carrier with fixed wingsails that will stretch an extraordinary 100m into the air.

More sailing ships to come

In France, Neoline have developed a more conventional sailing cargo ship and agreed a letter of interest for its construction. They plan to use the Solid Sail being developed by the French shipbuilding and fleet services company Chantiers de l’Atlantique. It’s a freestanding mast with a rotating boom setting a fabric headsail and solid panel mainsail – panels that Multiplast are building.

There are several projects in the UK. British yacht design firm Humphreys Yacht Design and sailing software tools designer, Dr Graeme Winn, are involved with Smart Green Shipping. In late July, they announced a £5m investment from a mix of private industry and Scottish Enterprise for a three-year R&D project to develop and test their FastRigs wingsail and digital routing software. They plan to put a demonstration unit on a commercial ship by 2023.

Also out of the UK is the Windship project, with a board of directors that includes yacht designer Simon Rogers and former Sparcraft director David Barrow. They’re proposing sets of three vertical wings, each 35m high.

“We believe,” Simon Schofield told me, “that wind technology has become mainstream in shipping… we’re seeing announcements almost weekly of new technologies being trialled and fitted to ships and we are set up specifically with a supply chain for volume. We’re doing a run now, but we want to be doing hundreds next year.”

Yes, that’s right. Hundreds. If there is such a thing as first-mover advantage, BAR Technologies appear to have it.

BAR started the WindWing project with a computer simulation, but merchant ships presented new problems. “The ships have a yaw balance [weather or lee helm] problem,” explained Schofield. “They’re not designed for wings. So, you’ve got to monitor rudder limits.” This is exactly the kind of problem that’s fundamental to designing well-behaved, fast and comfortable superyachts, and it’s no surprise the same approach was taken by VPLP with a similar background in elite yacht racing design.

Complications

The problem is even more complex with commercial ships. The leeway the wings induce has other side effects. The loading on the propeller changes, and that impacts its efficiency. “We also needed to model the engine plant, because we are moving engines away from their optimum efficiency points, so their fuel consumption changes,” said Schofield. Eventually, using these tools, they developed the design parameters for the WindWings.

“They are three-element, rigid wingsails,” said Schofield. “The first ones we’re doing are 37.5m aerodynamic span, about 20m in chord and rising to about 45m off the deck. So big bits of kit… We operate in up to 40 knots of true wind speed, with a 25% gust factor on top. So if it’s 40 gusting 50, that’s fine.” After that the WindWings are feathered, much like a wind turbine.

Despite the advanced state of BAR Technologies’ WindWings project, it’s probably too early to predict who the big winners will be in this race. In fact, given the demand from the world’s merchant shipping fleets, it’s likely there’ll be several.

We can also be sure all this energy, innovation and investment is going to produce significant advances in sailing technology. Perhaps, in a few years’ time, the gentle whirr of electric air compressors will have found their way from the paddleboards on the beaches of the River Hamble, to former motoryachts in the river’s many marinas.

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