White Heaven III, the largest vessel to date from Dutch builder Moonen Shipyards, has a smart, modern profile that hints at speed. Yet this 120-foot tri-deck is uncompromising in her design for operation at a relaxed pace, with a continuous cruising speed of 12 knots and a top speed just slightly higher, at 13.2 knots.
Everything about White Heaven III says extended cruising, and quite emphatically so. Her full-displacement hull form has round bilges to soften the ride and reduce power requirements at moderate speeds. She sports a bulbous bow, not cylindrical but shaped in accordance with the latest technology to cancel out the resistance-increasing bow wave and avoid slamming in heavy weather.
A shallow transom stern ensures the stern wave will be as low as possible. It also provides room to carry a pair of deep, high-aspect ratio rudders for better control with minimal drag. Fin stabilizers are mounted at the turn of the bilge, in an optimum location about two-thirds LWL aft.
The propulsion package is also geared, literally, to a sedate, sensible pace. The Caterpillar 3412 diesels, capable of a maximum of 1,350 horsepower, have been set to deliver only about half that on a continuous basis, 671 hp at 1800 rpm. The reduction gear ratio is 3.5:1, so the propellers will turn at a subdued 514 rpm. This is only a third of the rotational speed found on some higher-speed boats with 2400 rpm engines and 1.5:1 gears.
The benefits of this engine and gear package are manifold. Fuel efficiency is excellent, at 33.7 gallons per hour at full power, or 0.0502 gallons per horsepower hour. This yields the best range for a given length and displacement. Noise and vibration are kept to a minimum, so White Heaven III needs no heavy, expensive insulation solutions. The machinery is not being pushed to its limits and should run forever with few breakdowns. There are only so many horses built into a ton of cast iron; you can take them out quickly for a short-lived rush, or you can do it slowly for years of trouble-free pleasure.
On the downside, low propeller speed demands larger propellers to achieve the best propulsive efficiency. This generally means more draft, and White Heaven III is no exception. Her 8-foot draft is far from ideal for cruising the Bahamas and other shallow-water venues. With the deeper draft in mind, she has been fitted with a full-length keel to provide some propeller protection. The keel, along with the deep rudders, also reduces the chance of broaching and helps keep her on course in following seas.
A reduction in top engine rpm and a higher gear ratio can sometimes lead to difficult idle-speed maneuvering. There is less range between idle speed and full speed, so some vessels must be bumped in and out of gear while docking or transiting slow-speed zones. Fitting a trolling valve or other means to slow the propeller independently of the engine speed is often the solution. I didn’t have a chance to check this on White Heaven III.
Her hull is steel, with integral tankage providing good fluid capacities and forming a double bottom for grounding protection over a considerable proportion of the hull’s area. In addition to fuel and freshwater tanks, she has holding tanks for black and gray water. The aluminum superstructure is joined to the hull with a welded joint that uses an explosively bonded strip. This system eliminates the corrosion between dissimilar metals that sometimes plagued older vessels built with lapped, bolted joints.
The arrangement of White Heaven III’s lower and main decks is not unusual for a yacht her size. Four large double staterooms are below, in addition to two single-berth cabins and a double for the crew, along with a nicely sized mess and lounge area. The main deck has the owner’s stateroom and study forward. There is a spacious entry lobby to starboard and a large galley to port. Aft, the dining room and saloon share an extended space with a bar, and open onto a fully covered afterdeck.
What is unusual, however, is evident upon careful examination of the lower deck plan. One of the four double staterooms, all of which would normally be guest staterooms, is designated as the captain’s cabin. This is because the upper deck carries a second owner’s stateroom, as well as a serving pantry and a small lounge. The arrangement, though not for everyone, suits this particular owner and would offer flexibility for charter.
Central and wing helms are at the pilothouse, so the flying bridge deck is devoted to guest relaxation. The extra-wide radar arch shades the whirlpool spa. A large bar, sunbathing area, dining area and additional seating fill out the deck.
White Heaven III’s construction and outfitting were well under way when I visited the yard last year, and her sea trials coincided with a return to Holland this spring. This gave me a great opportunity to evaluate her, and a chance to discuss her design at length with Emile Bilterijst, managing director of Moonen. Emile took over managerial duties from yard founder Rien Moonen in January 1998.
I couldn’t help but feel a kinship with Bilterijst, and not just for his obvious appreciation of fine craftsmanship and sound construction. Like myself, he started his career with a naval architecture degree and experience in the realm of commercial ships before finding a home in the world of large yachts.
With this background, he is certainly capable of directing the Moonen staff in building much larger yachts, but his plan is to concentrate on a full range of vessels under 125 feet for the immediate future.
The recently completed 72-foot Lady Jalinka is one example I was able to try out during my visit. As finely finished as her larger sister, this flush-deck model anchors the lower end of a line of Moonen displacement cruisers that includes an 84-foot flush-deck, a 94-foot raised pilothouse and a 114-foot tri-deck motoryacht.
To whet my appetite for the next visit, Bilterijst shared a preliminary rendering for an even smaller design that should appeal to yachtsmen in Monte Carlo and Ft. Lauderdale looking for the ultimate day boat.