Central Yacht, a partnership of architects, engineers and captains with extensive operational experience of significant yachts worldwide, have talked to SYT about one of their most innovative projects, based on an length of 70-75 metres, and looks at the achievement of ultra-high speeds combined with long-range cruising and to be able to use standard marina facilities.
The power plant had to be very flexible and powerful, and hull construction no wider or deeper than a conventional monohull. The innovative hull is based on the SWATH principal, but using a single hull for reduced beam. Stability at high speed is achieved by hydrofoils with active ride control. The submerged hydro-efficient torpedo gives great stability at anchor and when at slow speed in long-range displacement mode. As speed increases, the upper hull first enters the planing mode before rising on the foils, which are controlled automatically to compensate for pitch and roll. The torpedo always remains submerged.
The highly flexible and efficient power and propulsion package is a modified gas turbine/diesel-electric hybrid. The design features a central 20MW (19,388kW) gas turbine electric generator, a centreline electric propulsion motor of 15MW (14,913kW) and two conventional 5MW (5,219kW) wing engines driving through a combined shaft generator/motor.
In sprint mode the gas turbine powers the central electric motor and the two wing electric motors. For fast cruising, the gas turbine is not used and both wing engines can be used to achieve 20 knots plus. For economy cruising of 15 knots, a single wing engine can be used in combined propulsion and generator mode with the electricity used to power the other wing engine electric motor.
The principal design benefits are very high speeds and safety; speeds of 50 knots can be achieved with great security. Loss of propulsion power, or collision of a foil with an underwater obstruction, will cause the hull to settle down into high-speed planing mode and not result in catastrophic deceleration, as well as extended cruising range. The very adaptable power plant configuration and capable hull design provides a range of 7,000nm at slow cruising speeds. However, even when fast cruising at 25 knots, the vessel can still comfortably achieve transatlantic crossings.
Using a monohull configuration means that standard marina berths can be used, giving much greater cruising possibilities. Additionally, the hull form and large foils offer superior static stability when at anchor. Active control of the foils will reduce roll at zero speed to imperceptible levels. At speed, the foils’ positioning far forward and astern means that effective control of pitch and roll can be achieved.
The different technology used in the vessel is already in use and well proven. Combining the different design ideas into a yacht is groundbreaking, but does not compromise any of the existing technology, with the first turbo-electric yacht delivered in the 1930s.