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[ TRENDS / FOILS ]
IN FLIGHT ON THE WATER From the America’s Cup to surfing – much more than a passing fad, hulls that soar above the water seem to be the future of sailing. It’s a technology that makes sail yachts more efficient and cuts the amount of fuel required by motor-powered craft, lessening their environmental impact
@Carlo Borlenghi
by Fabio Petrone
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The foils on Luna Rossa and Emirates Team New Zealand in the most recent America’s Cup have focused attention on this technology, the new frontier of sail
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[ TRENDS ]
E
ngineer Enrico Forlanini, inventor of the hydrofoil, would probably be pleased to see how the concept he came up with in the early 20th century has developed. The generation of hydrofoil craft currently making its appearance exploits his idea of lifting the hull out of the water when under way by using underwater appendages of a special
size and shape. The extent of their effect depends on the speed of the craft – the faster it goes, the more the boat lifts out of the water, drastically reducing its wetted surface. The idea of the yacht as hydrofoil, reducing drag and therefore improving performance and consumption, is already well-developed in the yacht-racing industry, where high-profile America’s Cup contestants have given the technology global visibility. Foiler Moth, Flying Phantom, RS600, C-Class and Nacra 17 (an Olympic class introduced at the Rio games in 2016) are just some of the designs enjoying increasing popularity in international yachting circles, not to mention the hordes of prototypes that small builders, technical institutes and design studios are making, with a single aim – to offer, fast, entertaining and acrobatic foil sailing with physically challenging boards for athletes with lightning-fast reactions who aren’t afraid of hurtling down the waves at breakneck speed or boats that excite the new cohort of enthusiasts, the young, with the adrenalin-charged excitement, thrills and fun they can provide. In a nutshell, the foil concept is now being borrowed for use on production sail and motor yachts. The most recent types to experience this transformation are service tenders and water toys – these exert a great attraction for owners as flying on the water is an exciting experience for all on board. The first generation of widely-available “flying” sail yachts was intended for fans of single type racing, and Beneteau’s Figaro 3, the first single-hull with foil on sale to the general public, was followed by racers like the Persico 69F and Club Swan 36. Meanwhile, the foil motoryacht market is offering craft targeting a more varied clientele and reflecting a greater emphasis on sustainability. Take, for example, Foiler, the Flying Yacht, by Enata Marine, and Candela Seven
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@Francis Demange
This page, top Foiler, the Flying Yacht by Enata Marine. Above, the Swedish runabout Candela Seven and left, Seabubbles, the “flying” taxi. Opposite page, the Hyper Yacht HSY38, what could well be the first superyacht to be equipped with foil technology. These are a few examples of foil technology in the motoryacht sector
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[ TRENDS ]
Foil technology is becoming increasingly popular on single-type yachts. Photo, top, the Beneteau Figaro 3 and right, the Persico 69F. Below, foils
@Marta Rovatti Studihrad - 69F media
are now to be seen on surfboards
– the hydrodynamic efficiency of these yachts, generated by sophisticated software for managing the underwater appendages, enables them to sail entirely out of the water at impressive cruising speeds even when driven by relatively low-power engines. This means that such craft are ideally suited for the installation of electric or hybrid motors that can now combine good performance with sufficient range for everyday use. One larger example is a concept that could be the first foil superyacht, the Hyper Yacht HSY38. In collaboration with architect Daniele Natoli, Leopoldo Rodriquez, great nephew of the founder of the Rodriquez yard, which wrote the book as far as commercial hydrofoils are concerned, has presented an interesting 38-metre open flush deck with new generation, even more efficient foils – at a cruising speed of 40 knots, it has a range of 700 nautical miles.
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