Boat International US cover story: "A client’s brief for the new 154ft Nilaya was so advanced and specific...


Boat International US cover story: "A client’s brief for the new 154ft Nilaya was so advanced and specific...


…that it ushered in new building methods at Royal Huisman. Marilyn Mower explores her featherlight construction and innovations.”

The new Nilaya supersloop: cover boat of Boat International US edition / Showboats, June 2024


Sailing evolution

The path to building the new Nilaya began with a years-long refinement of ideas. The subject under consideration was how to replace a 112ft high performance cruiser delivered by Baltic in 2010, a boat with plenty of podium finishes as well as many miles of family cruising over 12 years. This would be, in other words, the difficult follow-up to a smash hit.

“My brief for the new Nilaya was that she should be versatile, comfortable and safe; a yacht conceived for worldwide cruising in style, yet capable of hitting important racing targets. I wanted her to be fast in light winds, enabling us to cruise without an engine as much as possible,” the owner says.

This new Nilaya can rightly be called a development of her predecessor, featuring a similar racy, low profile, straight bow and wide transom. But with more than 8ft extra beam and 43ft more length, the increase in interior volume and on-deck living area is immense.

Nilaya is the most advanced sailing yacht Royal Huisman has delivered to date. Her build was a three-year process — one year of preparation and two years of construction. Left: the hull was turned in 2021

The owners wanted a lot, some of it difficult to reconcile: the capability for longer journeys without sacrificing speed, and a quieter, stiffer boat. They laid this problem at the feet of their team, California-based naval architects Reichel/Pugh and Nauta Design of Milan, who, along with owner representative Nigel Ingram of MCM, had created the previous Nilaya.

The owners’ emphasis on comfort for this Panamax sloop pushed Reichel/Pugh to collect data on wave heights, wave periods and wave and wind direction in cruising areas on both sides of the Atlantic. They did this, naval architect Jim Pugh says, not so much for sailing but for comfort while motoring, which happens a lot during Mediterranean summers.

The endgame was to work out weight distribution and an underwater profile that would deliver comfortable passages. After design studies in both carbon and aluminum, and optimization via computational fluid dynamics, Reichel/Pugh proposed tank testing 12 models.

Tapering the top of the
mast saved 110 pounds.
Rethinking the HVAC
system saved more
than 1,300 pounds…
and so it went

Above: the weight-saving twin anchor system with fiberglass chain lockers and titanium arms that swing the anchor over the bow. Throughout the build, Royal Huisman took a hybrid approach to materials, mixing carbon fiber with Alustar aluminum where it made sense. The entire 57ft coachroof and guest cockpit area, the keel trunk and the recessed tender well on the foredeck are full carbon fiber

“Our initial recommendation was for carbon fiber,” Nauta co-founder Mario Pedol says. “I came to this project thinking that aluminum construction would weigh 60 to 70 percent more than carbon. But at the same time we knew the owner was determined to have a long-range cruising boat with all the amenities expected on a superyacht and for it to be much quieter than typically achievable with carbon fiber.” Sound and vibration isolation involves weight, so it would come down to setting priorities. The owners couldn’t have it both ways.

Or maybe they could. Royal Huisman, which was very keen to bid on the project, suggested the answer was not either/or but both. Huisman began adding carbon-fiber elements to its aluminum yachts in 1997. Nilaya’s owner, who knew the builder’s attention to superyacht quality, was intrigued, and directed the three parties to explore a hybrid carbon/aluminum solution.

To achieve the low weight required for performance under sail or power, Royal Huisman knew the answer was not just a matter of popping a carbon-fiber coachroof atop an aluminum hull. It called on the engineering and materials expertise of its sister company Rondal and worked with European Space Agency technology on detailed finite element analysis (FEA) to investigate every possible area of the hull, deck and interior for strength-to-weight ratios, while recalling that comfort was an equal part of the equation.

FEA modeling guided the choice of carbon fiber, varied Alustar plate thicknesses and frame spacing to maximize hull stiffness while minimizing total displacement. In some cases, carbon fiber would be bonded to aluminum to increase its stiffness without adding much weight or bulk. Utilizing in-house parametric software to evaluate various structural designs, the builder found major weight savings by using carbon or carbon/aluminum hybrid sections for the door frames, hatches and deck.

Reichel/Pugh, Royal Huisman and Ingram calculated weights and balances nearly frame by frame to guarantee the best motion under way. If carbon could replace metal in a way that made sense, it was subjected to a cost-benefit analysis, and if the increased costs of molding a carbon part resulted in a better boat, the owners approved it.

Weight saving remained front of mind throughout the build. For example, Nilaya’s blade jib uses lashings to connect to its forestay instead of a headstay lock – thus saving 220 pounds. Tapering the top of the mast generated a saving of 110 pounds. Rethinking the HVAC system saved more than 1,300 pounds, reducing teak deck thickness from 0.6in down to a third of an inch saved almost 3,000 pounds, and so it went. In the end, Royal Huisman delivered a hull 11 percent lighter than its typical advanced Alustar construction, and by applying the methodology to systems and the interior saved another four percent in displacement.

Forward thinking on backstays
On large yachts with robust beams, easing the windward runner (which helps hold the mast in column) while taking up on what was the leeward runner, takes at least two people who must be in sync with the helmsman and the mainsheet trimmer. Nilaya’s innovative technology allows the crew to execute this important maneuverer at the touch of a button. Horizontally mounted hydraulic cylinders under the aft deck release and take up the running backstay cables led from underdeck winches by titanium fittings at precisely matched speeds. The genius of the system is the precision-machined titanium “hook” that automatically snares and locks the load end of the windward sheet. On the new slack side of the system, a matching hook releases and drops gently into a little fitting that holds it snuggly atop its winch until it is needed again.

Considering the
backstay loads,
minimizing risk
to the carbon-fiber
mast and the people
beneath it deserved
serious attention

Mahogany joinery lends a classic and homey touch to the interior.

The owner’s requirements included a high-tech rig and very advanced gear to control the sails. He also inquired about the possibility of automating the running backstays and eliminating the huge deck winches controlling them. When a yacht is racing upwind, control of the running backstays during a tack is critical. Unless the ballet goes precisely as choreographed, the tack is stalled, boat speed drops, and – in the worst case – the rig may be jeopardized. Considering the backstay loads on a sloop with a 205ft mast, minimizing risk to the carbon-fiber mast and the people beneath it deserved serious attention.

For this task, Rondal created its most advanced integrated sailing system, beginning with a first-of-its-kind backstay locking system. That system alone saved 2,650 pounds and 106 cubic feet of space in the lazarette.

“We set out to develop a totally different decision-making matrix for this project,” Rondal’s Bart van der Meer says. Usually, the naval architect specifies the sail area needed, the mast manufacturer creates the rig to hold it, the sailmaker supplies the sails and tells the builder where the deck hardware needs to go to trim them.

The builder then asks the winch manufacturer to develop gear sized to the loads and orders a hydraulic package to control it all. It gets assembled by the yard and then programmers create the logic software that makes things happen when crew push a button.

“The problem is that most programmers aren’t sailors and there is no communication with the crew about the boat’s operational profile. Most hydraulics suppliers size their package for maximum loads and then it’s up to the yard to make it fit somewhere, and the crew to figure it out,” van der Meer says.

Instead, for this project Rondal and Royal Huisman gave everyone a seat at the table during the development phase. Developing all the system needs in advance also meant that Nauta knew exactly the available interior volumes and shapes. All decisions were immediately shared to all parties in the form of updated electronic plan files. Royal Huisman also made a fullscale deck mock-up that could be tilted to simulate heel for approving handhold placement and to allow the crew to check sight lines at all angles. It enabled the owners’ team to decide, for instance, that they didn’t need a removable bimini and to refine the fixed bimini’s supports instead.

With Nauta and Reichel/Pugh having defined target weights for the interior, during construction every element was weighed going into the boat and all debris was weighed coming off. To stay within the interior weight budget, Royal Huisman made extensive sound attenuation studies and developed sophisticated composite panels in cork, foam and honeycomb. It made cabin mock-ups demonstrating three levels of sound insulation and allowed the owners to choose the level of quiet they wanted to pursue.

Nilaya, the largest sailing yacht yet by Nauta Design, features two guest cabins, a galley, a crew mess, chart table, an engineer’s station and four double crew cabins aft of the main salon, plus a media lounge, VIP guest cabin and owners’ full-beam suite  forward. The owners’ designer, May Vervoordt, chose interior materials and, with Nauta, conceived a bright color scheme against white lacquered walls and bronze-colored fabric and leather overhead panels. Mahogany furniture, flooring and ceiling frames give classic warmth and a homely quality, especially to the deck salon. Nilaya, after all, means “peaceful abode” in Sanskrit.

Nauta’s experience with racing boats means that everything has its place – and in most cases, that is out of sight. Case in point, the deck salon has an owners’ pantry where guests can avail themselves of coffee, drinks and snacks but they wouldn’t know it was there if it wasn’t pointed out.

The full-width owner’s suite features a walk-in wardrobe, an office and seating area and a king-sized bed. Large hull windows bathe the room in natural light. The cabin was a design challenge as it lies beneath the tender bay, but the overhead decorative treatment balances the bay’s central dip with higher side passages, giving an excellent perspective on the cabin’s impressive width.

The VIP, which can be arranged as twin berths or a double is to port, opposite a cozy TV lounge six steps lower than the deck salon. The identical en suite guest cabins aft of the salon convert into doubles and are both equipped with additional Pullmans, meaning up to eight guests can accompany the owners.

With a mast height of 205ft, Nilaya can sail into the Pacific, fitting under Panama’s Bridge of the Americas at low tide. Note the curved spreaders that Rondal developed to take advantage of the very narrow headsail sheeting angles possible with Doyle Sails structured luff sails

Mindful of the mission to cruise as well as race, Nauta Design developed three distinct outdoor guest areas in addition to the twin helm positions. The almost 33ft-wide transom includes a hinged section that folds hydraulically to form a staircase that lifts out of the way to launch the crew tender. On the aft section of the cockpit are two innovative sun loungers that adjust to compensate for the yacht’s heel. Removable railings from the transom to the guest cockpit guarantee that crew and guests are never more than two steps from a grab rail.

The guest cockpit, meanwhile, is shaded by a carbon composite hardtop with windows. Under this, the dining table can extend to seat 14 guests. Finally, the foredeck features a partially recessed tender bay that can become a cozy cockpit at anchor with a hi-lo table and fitted cushions. An awning can be strung from carbon fiber poles that store in a deck hatch.

A lighter yacht needs less power for motoring, in this case, one fewer generator and gearbox — a factor that leaves more space for interior accommodations and saved another 4,400 pounds.

The single propeller can be powered directly from the engine and/or electrically, either from batteries or a generator, which eliminates the need for a third get-home engine. The team got to test the results extensively. The owner, captain Romke Loopik and pro race team captain Bouwe Bekking were on board for Nilaya’s first transatlantic in November. It was a fast 10 days with instruments recording a top speed of 20-plus knots, and the owners’ verdict was “very comfortable and fast”.

“For such a large yacht, the acceleration is exciting as she rapidly reaches high speeds,” Ingram says. “Twin rudders and the light, positive steering give superb maneuverability and she seems to be reaching all her targets with ease. Rondal’s sailing systems enable fingertip control of the massive loads involved.” At the 2024 St Barth’s Bucket in March, Nilaya proved the point, winning on the third day of racing and finishing third overall in her class in her first ever Bucket regatta.

Royal Huisman CEO Jan Timmerman says the innovations on Nilaya can be applied to future sailing yacht builds. “The owners deserve congratulations for pushing everyone to achieve just a little bit more and for encouraging innovation at every step. Nilaya will be the world’s lightest sailing superyacht for her length. She rewrites the script for aluminum high-performance yachts.”

She may be lightweight, but there is no doubt that Nilaya is a technological heavy hitter.

Sail innovation 
Nilaya was the first yacht fitted with Doyle’s “structured luff” sails, which distribute the load a little differently through the material and sheet flat. So flat, in fact, that Rondal had to develop radical new curved carbonfiber spreaders that are both shorter and more aerodynamic than anything previously available. Rondal also developed a hybrid captive winch with carbon-fiber drum that’s half the weight of other captive winches.

General arrangement
Main deck: the tender bay can be covered with a carbon composite covering to become a flush deck. The shaded guest cockpit is lined with sofas around the dining and coffee tables. A 13ft crew tender stows behind the transom. – Cabin deck: the owner’s suite forward includes a full-width cabin and generous en suite. The VIP cabin can be arranged as twins or a double. The deck salon enjoys near all- round views. A Pullman berth in each aft stateroom means Nilaya can take up to 10 guests. See layouts? Link (opens a new tab). 

LOA 154′ 2″ | LWL 147′ 8″ | Beam 32′ 10″ | Draft (keel up/down) 14′ 9″/22′ 8″ | Gross tonnage 282GT | Engine Scania DI 16 090M + 140kW PM motor/generator | Generators 2 x 129kW Volvo D4-175 | Rig Rondal carbon Panamax mast and furling boom | Sails Doyle Sails, structured luff | Sail area (downwind) 23,046 sq ft | Fuel capacity 3,963 gallons | Freshwater capacity 1,057 gallons | Owners/guests 8-10 | Crew 8 | Tenders 23′ Xtender RIB; 13′ inflatable | Construction Aluminum and carbon composite | Classification Lloyd’s SSC hull certificate | Naval architecture Reichel/Pugh | Exterior and interior design Nauta Design | Interior decor May Vervoordt | Builder/year Royal Huisman/2023

This article was published in Boat International US edition / Showboats, June 2024.