The new Infiniti 100S “Superyacht” is set part from competitors by the incorporation of technological breakthroughs – not least, the remarkable Dynamic Stability System and the use of high-quality carbon fibre materials.
The idea of retractable yacht keels that are actually deployed in operation probably hit the consciousness of most people only when the amazing America’s Cup AC72 catamarans reared out of the water and tore across San Francisco Bay at speeds in excess of 40 knots. They looked fabulous as they rode two, three or more metres above the waves and outstripped the wind itself. However, remarkable as they were, the reality is that those hydrofoil-keel daggerblades are designed for racing and are impractical for the burgeoning leisure sailing market. They are as useful to a superyacht, for example, as a Formula One racing car is to a family holiday – but they do serve to spread some understanding of technology to the wider world.
A different angle
Retractable keels are not exclusive to the racing world. Dynamic Systems Technology (DSS) has been around for some time and, while it is also a retractable keel, it differs from the AC72 daggerblades in two important respects. First, it is designed for – and used – on monohull vessels; and second, the orientation is horizontal, rather than vertical. But they share one ultimate objective: to improve performance. The second, in the case of DSS, is to improve comfort as well. When the yacht is being sailed, the retractable foil is deployed leeward – the opposite side of the boat from the origin of the wind – where it creates Righting Movement. This aids stability, keeps the boat more upright and thus exposes more sail area to the wind, which boosts power. Unlike the AC72s a DSS-equipped yacht does not rise out of the water and run on the foil, it heels over less and thus keeps more of the hull above the waterline, which reduces drag. The DSS foil, which is mounted forward of the fixed keel, reduces the pitching that is a cause of seasickness. Yachts fitted with DSS are thus faster, smoother and more comfortable.
Building a superyacht
On April 30, 2013, Infiniti Yachts, which is based in France, and Danish Yachts of Skagen, Denmark, announced the construction of the first Infiniti 100S superyachts, which are being built on the terrace of the Real Club Nautico de Palma. The yachts contain a range of design, construction, naval architecture and material advances. Welbourn Design, the inventors of DSS, has been working closely on the project with Gurit, the structural engineers, and Design Unlimited, who are responsible for the interiors.
Gurit is developing a structure that meets the requirements regarding weight but, at the same time, allows for a stylish interior. Key areas included the engineering and manufacturing processes to ensure cost effective production. According to Alex Shimell, Marine Consultancy Director at Gurit, the structure is based on a relatively thick foam sandwich shell, which is intended to reduce the interior structural elements and thus allow more room for built-in noise insulation. The approach also improves build times.
“Gurit will work closely with Danish Yachts to develop the build concept and construction details to enable them to achieve the structural weight targets, while maintaining control of the build hours,” Shimell said. “We will also work closely with Design Unlimited and Hugh Welbourn to incorporate the looks and design features that have been designed in the Infiniti 100S”.
Design, development and reality
Welbourn Design has overseen the intensive programme of tank testing and on-the-water evaluation that Infiniti has been conducting. The development of Velocity Prediction Programs (VPPs) enabled the sail designers to correlate the on-the-water test results with those derived from tank and CFD analysis. The interior provides for six guests in three en-suite cabins. As befits a superyacht, it is both luxurious and practical. It is designed to be comfortable while cruising at speeds in excess of 20 knots, which would normally give passengers an exciting, if bumpy ride.
The cockpit is deep and secure and designed to be both safe and dry when sailing. The cockpit and saloon are designed to merge in an uninterrupted flow and to allow substantial natural light into the saloon area. The interior is modern and open. The crew is accommodated aft of the companionway.
Specialised materials and advanced resources
Danish Yachts specialises in the use of advanced carbon fibre composites and produces vessels with hull and superstructure made entirely of carbon fibre. It has its own high-temperature curing facilities, as well as on-site joinery and metal shops. By using top-grade carbon fibre, Danish Yachts builds structures that are up to 50% lighter than comparable advanced materials. Such a large weight reduction enables greater structural stiffness, as well as increased speed and improved handling. As carbon fibre’s thermal expansion is zero, the hull is always operating at optimum. The stiffness and resistance of carbon fibre also provides the reassurance of high energy absorption in the event of impact.