Skat — By George L. Petrie
— May 2003
Covering All the Angles
|Part 2: As impressive and imaginative as her styling and appearance may be, those aspects are but half the story of this yacht.|
The yacht's interior spaces echo the same design themes as her exterior: flat surfaces, angles rather than curves, and a minimalist decor (if one can imagine using the word minimalist in connection with a 232-foot yacht). Bulkheads, overheads, and decks are finished in muted tones that complement the yacht's gray exterior, while simple but boldly colored furnishings add visual punch. There is nothing fussy or pretentious. She's not a gallery for showing off artwork and sculpture, and there are no precious fabrics to be spoiled by a stray glass of wine. Skat is a yacht to simply come aboard, relax, and enjoy.
As impressive and imaginative as her styling and appearance may be, those aspects are but half the story of this yacht. Every facet of her engineering, construction, and systems reflect a strict attention to detail and a singular commitment to purpose.
For example, consider the design of her hull, a full-displacement form intended for cruising at 15 knots and capable of a 17-knot top speed. An extensive program of scale-model testing was undertaken at the Hamburg Ship Model Basin to confirm the naval architect's design calculations and to establish the yacht's speed, fuel consumption, seakeeping, and maneuverability. At a model scale of 1/10.4, the scale model itself was the size of a runabout, more than 22 feet long. Self-propelled, the model was fitted with shafts, brackets, stabilizer fins, and rudders, along with dynamometers and instruments to measure propeller thrust, torque, and rpm at different speeds. The model was built to accommodate either of two different forebody shapes, a normal yacht stem or a more ship-like bulbous bow. During the course of testing, optimization of the bulbous bow was found to produce a fuel savings of about 15 percent. Similar optimization of the rudder and stabilizers produced an additional nine percent savings in fuel consumption.
Equal rigor was applied to the design of the machinery and systems, especially in relation to control of noise and vibration. Two big, stainless steel-encapsulated exhaust systems dominate the upper regions of the machinery space, reducing main engine exhaust noise to barely audible levels. Both main engines and all three gensets are mounted in a sound-absorbing enclosure within the center of the engine room, on an isolation foundation that eliminates the transfer of noise and vibration into the hull. In addition, floors and ceilings throughout the yacht are soft-mounted to eliminate propagation of noise or vibration through the structure.
All main systems are redundant, and in fact, the yacht is able to achieve a speed of 13 knots on just one engine. A cooling pump integrated into the gearboxes assures safe operation on one engine by pumping oil through the idle gearbox. The shaft of the idle engine can be disengaged, leaving the idle propeller and shaft to freewheel.
Other details received no less attention. Consider, for example, the design requirements for the motorcycle lift, which runs from a lower deck up to the main deck. In its lowered position, the elevator platform had to have a low profile, but it could not be recessed into the deck. In the raised position, the platform had to be flush with the main deck. But to complicate matters, all mechanical parts had to be hidden from view when the platform was in its raised position. The solution was a drive system similar to that used for theater stages, using a chain hoist to raise the platform about two-thirds of the way, and a scissors mechanism within the platform for the remainder of the lift.
Equally sophisticated is the system for launch and retrieval of the tenders through large, rectangular hatches in either side of the hull. A system of hydraulic rams pushes the hatch door straight out to the side, then rotates it to a horizontal position. A pair of horizontal beams then extends through the hatch opening, permitting launch and retrieval of the tender. The whole operation occurs with the touch of a single button, in about as much time as it takes to read this description of it.
Skat abounds with impressive and innovative features, from the vacuum system in her bilge to the helideck on her bridge. With mathematical precision, her design and construction cover all the angles.
Lürssen Phone: (49) 421 66 04 166. www.lurssen.com.
This article originally appeared in the April 2003 issue of Power & Motoryacht magazine.