Doyle Sails: Structured luffs expand both into a wider market and also further up the size range
by Ivor Wilkins/Seahorse Magazine 1 May 16:24 PDT
Maximus sailing in the St. Barth's Bucket Regatta 2024 © Cory Silken
At Europe’s major superyacht crossroads of Palma de Mallorca, the three key experts at the Doyle Sails loft are each involved in projects widely diverse in nature but all sharing a commitment to extract maximum benefit from the company’s groundbreaking Structured Luff technology.
As grand prix pioneers have tested and validated the extraordinary promise of Structured Luff sails – reduced rig weights, forestay loads and sag – enthusiasm for the product has expanded both into a wider market and also further up the size range. Doyle Sails’ Structured Luff technology is now fully integrated into the design and engineering calculations of some of the biggest superyacht projects on the boards.
For Chris Sherlock and his two Doyle Sails Palma colleagues, Luke Molloy and Scott Zebny, this shift has seen the loft’s workload grow exponentially over the past five or six years.
“Superyacht owners are increasingly interested in Structured Luff, even those who are not necessarily racing,” says Molloy. “It is almost a rare event now not to provide a Structured Luff option when quoting new sails.
“It obviously depends on the capabilities of the existing boat and what the owner’s appetite is for upgrades. If it is a new build, then, without question, nearly all the sails now are Structured Luff.
“Owners understand that you can get more range out of each individual sail and more performance for the boat. Most of these superyachts now are performance based and the owners are spending a lot of time, money and resources to get the best out of them.”
On Chris Sherlock’s plate are two perfect examples of how Structured Luff can revitalise an existing yacht and become a fundamental design element of a very ambitious new build – both for the same owner.
The new build is Project Zero, a 69m ketch featuring the modern classic profile and high-performance underwater hull and appendages typical of the Dykstra design studio. The ambitious defining feature of this yacht, however, is to be self-sustaining for long periods with zero fossil fuel.
Drawing from a wide panel of experts in diverse and rarified fields, enormous effort has gone into maximising energy production, primarily through solar panels and hydro-generators, while minimising energy consumption – without sacrificing the customary levels of luxury and amenity associated with superyachts.
From a sailing point of view, the challenge for Doyle Sails was right up their alley. Most superyachts sail only in ideal conditions – not too much wind, nor too little and preferably only on a broad reach, thank you very much. This yacht, with a crew of 11, is required to sail well pretty much all the time with the wind on any quarter.
“A ‘normal’ superyacht sails about 15% of its life and motors the rest,” says Sherlock. “At about 50-60%, Hetairos is the current benchmark for a superyacht that actively sails more than most. Project Zero has to sail at 80-85%.”
Twin electric motors will be mostly confined to close quarters manoeuvring. For the rest, the sails will be called upon to do the heavy lifting in all conditions. Furthermore, they need to maintain decent passage times, despite an average 1.5-knot drag handicap from the underwater hydro-generators.
The sailplan borrows heavily from a Dykstra-Doyle collaboration on the similar size ketch, Aquarius II, which launched last year and takes full advantage of the load reductions offered by its Structured Luff wardrobe.
With a view to racing, however, Aquarius II was not compromised by any requirement to fit under the Bridge of Americas at Panama, whereas Project Zero must comply with Panamax restrictions. “Consequently, Project Zero’s mainmast is 6-7m shorter and the mizzen 3-4m shorter,” says Sherlock.
Nevertheless, by applying huge roach to the mizzen and mainsail, the sail areas on both yachts are virtually identical at 2,000m2 upwind and nearly 4,700m2 downwind. The downwind inventory comprises a Structured Luff cableless code zero and mizzen gennaker.
“The headsails are all Structured Luff,” Sherlock continues. “The genoa cunningham will put 20 tons of tack load into the sail itself, while the staysail, without any forestay, will carry double that load through the tack. There is also a Structured Luff mizzen jib.”
The main and mizzen both employ slab reefing. “We have to be able to reef while reaching,” Sherlock explains. “We cannot turn up head to wind under power to reef with in-boom furling systems. Also, slab reefing consumes less energy, because we can do it manually, without hydraulics.”
As much as the all-consuming Project Zero is technically futuristic in every aspect, Sherlock’s other major preoccupation extends back in time for close to two decades. This is the 100ft Leopard 3.
Sherlock has played a major role with Leopard 3 since it was built in 2007. From the outset, the boat was overburdened by its task as a luxury charter yacht, but beneath the opulent surface its athletic potential was always there.
“It is the right length, the right beam, it has a canting keel and dagger boards. If you were to design a high performance 100ft boat today, Bruce Farr’s original lines would not be far off,” says Sherlock.
Following a Leopard 3 charter, the Project Zero owner and his wife bought her in 2021 and set about unleashing all that performance potential. A crash diet saw all non-essential equipment and furnishings stripped out for a weight saving of 10 tons, while a total commitment to a wardrobe of Structured Luff Doyle Sails matched to a new carbon fibre rig significantly contributed to the weight savings, halved the runner loads and turbo-charged performance.
Leopard 3’s 2024 race results fully rewarded the effort with a line honours win in the RORC Transatlantic Race followed by sweeping the boards – 1st overall on IRC, 1st IRC Super Zero class, and Line Honours – in the RORC Caribbean 600 Race.
Ultimate validation, however, came when Leopard 3 was crowned IMA Maxi 1 World Champions at the Maxi Yacht Rolex Cup in Porto Cervo. (Also powered by Doyle Sails, George Sakellaris’ Proteus won Maxi 2 and Riccardo Pavoncellis’ Gaetana won the Maxi Multihull division).
Leopard 3’s stellar results in 2024 have only raised the appetite for more in 2025. Consequently, further surgery to shed a 2 tons more awaits in the form of a new keel fin, 1-1.5m deeper, a lighter bulb, changes to the position and rake of the dagger boards, and new lower aspect-ratio rudders to ensure the windward rudder clears the water.
If Doyle Sails’ Structured Luff phenomenon is attracting interest from bigger and bigger superyachts, the same is happening with full-on racers as well. It doesn’t get much more majestic than the J-Class – and Scott Zebny is working with a new addition to the fleet set to launch later this year.
“The whole focus is built around our Structured Luff technology,” says Zebny. “Our calculations indicate we will reduce the forestay max load from 34 tons to 18 tons. The Structured Luff tack will carry 15 tons, up from 5-6 tons with a conventional set-up. Forestay sag will improve from about 0.7% to 0.3% – 0.4%.
“That is why they came to us. This will be the first J-Class yacht in recent years to have a Doyle Sails inventory. It is a big deal for us.”
Zebny, who joined Doyle Sails Palma in late 2019, has been part of the J-Class scene for more than 20 years working with Endeavour, Ranger, Hanuman, Rainbow and Lionheart.
Alongside his Structured Luff J-Class new build, he has been closely involved with the Baltic Yachts Café Racers, the Baltic 108 WinWin and the 59m German Frers ketch Maximus, launched at Vitters in late 2023, among others.
He says the Café Racer concept, with no backstays or runners, perfectly validates the Structured Luff concept as the headsails absorb the loads with minimal sag, while a powerful luff cunningham in the mainsail enables a full range of shape adjustment.
WinWin, like Leopard 3, converted to a Doyle Sails Structured Luff inventory, with the typical modifications to support a powerful tack cunningham system. “It made an amazing difference,” says Zebny. “Instead of pulling 3 tons on the tack, it now pulls 12 tons. It’s been a complete transformation.”
The owner’s faith and investment paid off at the 2024 St Barths Bucket, where WinWin bested her larger sister, the Baltic 147 Visione, with a closely-fought 2,1,1 victory score in winds often in the high 20-knot zone.
Maximus made its racing debut at the 2024 St Barths Bucket and steadily grew more competitive through the season, ending with a division victory at the Palma Superyacht Cup. “The difference between us in St Barths and us in Palma is massive,” was the satisfied assessment of skipper Lars Loftus.
Zebny was part of the Maximus design team from its inception, with a full commitment to Structured Luff from the outset. “We started with a nearly year-long CFD study of the hull and rig, one result of which was a much bigger mizzen than originally planned.
“A yacht of that size would normally have headstay loads of around 45 tons,” Zebny notes. “We pull 22 tons on the tack of the jib, which means the headstay load is dramatically reduced. Yet all the professionals involved with the project have commented they have never seen so little headstay sag.”
Racing Maximus, according to the skipper, is like handling “two large sloops round the track with soft sails flying off both rigs”. The race crew of 35 earn their keep.
“In anything under 12 knots of breeze, we don’t even use snuffers on the spinnakers,” Zebny adds. “It is fun to watch about 1900 sq m of spinnaker come down in a conventional drop.”
Luke Molloy, the third apex in the triangle at Doyle Sails Palma, has ushered the Wally 93 Bullitt through a full Structured Luff conversion with similar success to the Leopard 3 and WinWin experiences.
Not long after launching, Bullitt was stranded by the Covid pandemic and spent a couple of years tied up in a Barcelona marina. While it was going nowhere, rival yachts like Leopard 3, Magic Carpet, Galatea and Open Season were all busy upgrading.
But, when Andrea Recordati, Commodore of Yacht Club Costa Smeralda, purchased Bullitt, he immediately set about catching up.
“The boat was originally specced for standard sails,” says Molloy. “As part of the refit, we worked with Judel Vrolijk, mast designer Steve Wilson and the people at Carbo-Link to accommodate a Doyle Sails Structured Luff inventory.
“By upgrading the tack cunningham and the halyard lock on the mast, we reduced the forestay load by about 60% and transferred most of that into the headsail luff, with impressive results.
“Bullitt is now fully competitive upwind, but there is room for improvement downwind. It would benefit from a taller rig, but we have been working really hard on the spinnaker designs to find the sweet spot between downwind sail area versus rating.”
On one of its first post-refit outings, Bullitt won the 2023 Rolex Middle Sea Race and, remarkably, even pushed the larger Leopard 3 all the way round the track for line honours. Storm damage prevented Bullitt from defending its Middle Sea Race title in 2024, but the team had the consolation of winning the Barcelona Maxi Regatta later in the year.
This year, Bullitt’s plans are to cross the Atlantic for the RORC Caribbean 600 series, the Nelson’s Cup regatta and a maxi series in the British Virgin Isles.
Molloy will also return to the TP52 Superseries this year. Having won the 2024 ORC world championship with Interlodge, he will continue racing on the same boat under new ownership with Vitamina colours. Also on Molloy’s busy 2025 calendar is working with the crew of the Botin 56, Black Pearl on their performance and sail package for the revived Admiral’s Cup.
For somebody who early in his career was a very reluctant offshore yachtsman – “I didn’t like it and wondered what it was all about” – Molloy’s annual race commitments continue to add prodigious sea mileage to the two Volvo Ocean Races he completed in 2005 and 2018. Safe to say he has well and truly figured out what it is all about.
These and other high-profile results-driven campaigns, which showcase the unique advantages of Doyle Sails, continue to draw interest from the much larger population of yachts of all sizes and ambitions passing through Palma and other lofts in the worldwide network. Increasingly, they want to share in the benefits, placing growing demands on service and sales.
Since Scott Zebny joined the Palma loft at the end of 2019, he has watched the operation triple in size and turnover. “We have expanded into another building, but already we need more people and more space,” he says. “It is a nice problem to have …”
About Doyle Sails: Doyle Sails strives to deliver success through high-performance, high-quality, custom sails that continue to redefine the boundaries of sailmaking technology and innovation; whilst connecting sailors to inspire, support and encourage sailing.
Our obsession with sailing takes us to every corner of the world and onboard every yacht. We become part of teams, share in the adventures of friends and families, sharing our knowledge and experience with those with the same passion. Sailing is in our DNA, and we are the custodians of a legacy that has been supporting sailors for four decades and counting.
By sailors, for sailors.