SEA EAGLE II Integrated Sailing System

SEA EAGLE II Integrated Sailing System

Just launched in Amsterdam after her sea trials were completed in the North Sea, SEA EAGLE II is now on her way to explore the seven seas. With her 81mtr LOA, she is the largest aluminum sailing yacht in the world. SEA EAGLE II, the impressive and already iconic superyacht, was built by Rondal’s sister company Royal Huisman, and designed by Dykstra Naval Architects and Mark Whiteley Design.

Her three carbon composite equally tall masts are equipped with advanced Rondal furling booms, which are styled and shaped to match the design of the yacht. Additionally, the aft and main mast are equipped with staysails for reaching courses. The yacht is designed with the maximum air draft of the Panama Canal in mind (Panamax 57,9mtr from waterline) for an easy passage between the Atlantic and Pacific oceans. The total sail area is distributed over the three masts to provide the freedom of various sail configurations for diverse weather conditions and courses.

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The masts are designed for an optimal balance between strength, stiffness and weight, and are manufactured from carbon composite. An impressive feat and exclusive to Rondal, is that each mast is highly customized and built from a unique mould to achieve an uncompromised mast tube shape and diameter. Also, each Rondal mast is built as one piece. This means that 80% of the mast thickness is constructed with full length, uninterrupted carbon fiber laminates, giving the mast exceptional properties with an advanced strength distribution. This results in a beautiful even bend, without ‘hard spots’.


A vital role was played by Rondal in realizing the Integrated Sailing System. This unique approach delivers optimization of sailing components and systems through and expert process of design and engineering. This The holistic approach leverages decades of superyacht experience, composite expertise and strong partnerships to realize the project with unrivalled quality; ease of sail handling and performance. The Rondal Integrated Sailing System comprises the three carbon masts with their furling booms, hydraulic boomvang, headsail furling systems, staysails, deck winches and equipment, captive reel winches and con-tinuous solid carbon standing rigging by Carbo-Link, all equipped with load sensing capabilities.


As on many other previous successful projects, Rondal has worked closely together with partner Carbo-Link for to create the best standing rigging available in the industry. Not only aesthetically pleasing with beautiful internal tangs and clean deck interfaces, the continuous solid carbon rigging is recognized for an its unmatched quality and performance. Together with leading sail maker Doyle Sails, and using advanced computer software, numerous load cases have were thoroughly engineered to define and establish optimal rig properties.


The powerful rig and optimized sailing systems ensure that the full potential of the hull is reached so that spectacular speeds over 21 knots can be achieved. This is done in the ultimate sustainable way by powering up SEA EAGLE II’s Rondal rig, which can carry over 3500 square meters of sail area. The complete sailing system is controlled by 34 Rondal hydraulic winches, of which 12 deck winches and 22 captive reel winches. The largest captive reel winches – for the yankee, staysail sheets and mizzen sheet runners – are capable of a tremendous 18 tons (18000 kg !) pulling load. To Rondal, SEA EAGLE II represents a full scope project with Rondal acting as a building partner – not only to realize the sailing system, but also to supply various entrances, deck hatches and large carbon composite tender hatches.


SEA EAGLE II’s rudder was also constructed by Rondal. Not just “a” rudder, as this is the largest carbon composite rudder in the world. Building the rudder from carbon composite, Rondal achieved a significant weight saving of 1750kg compared to a steel rudder. This accomplishment presented an interesting technical challenge as there was no pre-existing engineering data on composite rudders of this scale. For that reason an R&D project was started together with engineering partner Gurit and fiber optic specialist Com&Sens. During the construction of the rudder, optical fibers were embedded, allowing for mea-surements of torque and side loads during the build process as well as during sail trials. This real world data not only verifies but also advances future rudder projects. The SEA EAGLE II rudder project was recognized by winning the 2019 Boat Builder Award. For more details, view the more elaborate article here: https://www.