Hybrid Launch Rollover

We just returned to the office after a quick field trip around the top of Penobscot Bay, to the immaculate shop of French and Webb, Inc. of Belfast, Maine. The occasion (as if one needs an excuse to get outside on a crisp Maine March morning after watching the walls close in all winter long) was the rolling over of our latest design, the 29' hybrid launch mentioned in the last entry.

When we arrived, the boat had been pulled out of the shop, and a crane was positioned with a pair of slings under the sheer of the upside-down boat. The strip-planked hull has been sheathed with vacuum-bagged unidirectional carbon. The high-tech matte-black carbon was then hidden under fairing compound, which was sanded fair with hours of manual long-boarding before an epoxy primer was applied. Even the low gloss of the primer shows the fairness of the hull, which will need only a scuff of sandpaper and a spray of glossy topcoat to gleam like a piece of furniture.

With a few last-minute tweaks of slings and blocking, she was ready to roll. Here Peter Webb fine-tunes the braces placed to prevent damage to the sheer from the slings.

The actual rolling was accomplished in less than three minutes, with no drama.

There was barely enough time for the designers to reassure themselves that the shape they had created in the cyberspace of their 3-d modeling program looked even better in the flesh, before she was dropped onto a hydraulic trailer and slid back into the building shop for the next chapter in the story of her creation. However, there was time for a quick trip around the block to a nearby truck scale to confirm that her weight is meeting the design targets.

The slippery nature of this low-resistance hull is evident, as is the shapely stern and rakish bow profile. This bodes well for her success, whether pushed by the silent thrust of 7 kW of electric power or sliding along with no fuss at 15 knots under diesel power. Can't wait for launch day!

Stay tuned for a discussion on how this type of hull design can pay big rewards in efficiency for larger yachts.

An Eco-Friendly Hybrid Launch

One of Stephens, Waring & White's most exciting yacht design projects in recent years closes the distance between social responsibility and yachting.

Zogo will be a boat for the new reality of powerboating. Her design has been driven by our clients’ concern for treading lightly on their environment. Longtime summer residents of Stonington, Maine, her owners have enjoyed years of low-impact kayaking and rowing around the pristine and spectacular islands of Merchants Row, and when they decided to make the move to a powerboat, they sought a way to limit its environmental impact. Of particular concern were the vessel’s carbon footprint and its noise pollution.

Electric power seemed the natural solution, but the lack of facilities for recharging and practical limits of range and speed ruled out an all-electric installation. A conventional AC generator and motor was bulky and relatively inefficient, and also meant that silent operation under battery power would be difficult, if not impossible to achieve.

We have based the design of this 29’ launch around an alternative, based on cutting edge hybrid technology—an integrated diesel/electric propulsion engine from Europe. We became aware of this promising system while still under development in 2006, and the Zogo project appeared at just the moment that the system reached the production stage. The motor, manufactured by Steyr Diesel of Austria, incorporates a 7kW generator/motor between the bell housing and the marine reduction gear. A clutch allows the diesel engine to drive the boat directly while charging the battery bank, or the electric motor to decouple from the diesel and propel the boat with power drawn from the battery bank. Steyr offers the system in several different diesel power levels; for this project we selected the smallest, at 75 hp.

This integrated system has tremendous possibilities for the recreational marine market, and not just for propulsion purposes. It’s equally exciting for the mid-sized cruising sailboat, where electrical demands call for an onboard generator, but space and weight restrictions prohibit it. The unit is extremely compact, adding only a few inches of length and less than 100 pounds to the engine. In Zogo, this compactness allows considerable flexibility in the layout of the cockpit.

To maximize performance while minimizing power consumption, we paid particular attention to shaping a lightweight, low-resistance hull. Her narrow beam and light displacement mean that the relatively small diesel engine will push her to about 14 knots maximum speed. At cruising speed of 10-1/2 knots, she will burn about 1-1/2 gallons per hour. Under electric power, she will draw 48 volt DC current from eight batteries, for a maximum speed of about 7 knots, in virtually silent operation. A lightweight carbon fiber canopy shelters the cockpit from sun and rain, and provides a mounting platform for a sizeable array of solar panels to help recharge the battery bank.

Appearance played a key role also. It was important to the clients that the boat convey their sense of excitement and respect for the waters around Stonington, and thus we decided that she would combine classic proportions and grace with a more swoopy, modern aesthetic. The success of this look depends heavily on superb execution of deceptively simple details, and we are thrilled to be working with the craftsmen at French and Webb of Belfast, Maine (http://www.frenchwebb.com/); we have every confidence that they can put our concepts into reality in wood and carbon fiber. French and Webb expect a midsummer 2009 launch, and we are looking forward to our first silent, solar-powered lap around the harbor.

We believe this boat is just the tip of the iceberg in high-efficiency, low-impact powerboating. The technology has wide application, in both pleasure-boating and commercial watercraft, and we are looking forward to continuing to play a leadership role in the development and promotion of greener watercraft.

The Vintage 43 for Rivolta Yachts

Vintage 43

__Particulars__

LOA......................43’-0”
LWL.....................34’-9”
Beam....................12’-6”
Draft.....................3’-5”/6’-0”
Displacement.......15,900 lb.
Sail Area...............927 sq. ft.
SA/D Ratio...........24.4
D/LWL Ratio.......189
Power....................75 Hp Yanmar 4JH4-TE
Generator.............M4SE 2.2 Kw

Stephens, Waring & White Yacht Design continue a spirit of tradition-- more than forty years of excellence in yacht design, and the company is a result of recently reinventing themselves from their launch pad at Brooklin Boat Yard, in Brooklin, ME. The experience of the office spans the humble efforts of renowned designer and builder of wooden boats, Joel White, to today’s upbeat design office led by three men who have worked hard together for many years. Today Stephens, Waring & White advance their tradition into the changing world of modern yachting.
The work from this office can be described as "artful engineering" that is firmly rooted in the development of "Spirit of Tradition" (or modern classic) sailing yachts. These yacht designers have become well known for combining traditional grace with modern science and construction techniques, but are, also, seeking newer boundaries and attracting interest from more mainstream venues. Stephens, Waring & White, bring a vision and focus to provide any client with an exceptional experience in bringing their dream to life. In addition to years of design experience, Stephens, Waring & White bring to the drawing board a great depth of hands-on experience in all aspects of boat construction—the importance of that experience cannot be over-estimated. This is a key element in the range of services this office can provide.
A first for production yachts from the office of SWW Yacht Design, this lifting keel daysailer could be sailings’ version of the automotive industries’ “Crossover” concept in a Cadillac Coupe Deville. Rivolta Yachts, the well known Florida powerboat manufacturer, will commence production on the “Vintage 43” during the spring of 2009. The inventive yacht manufacturer is less recognized for its innovative sailboats, yet with plans to bring to market an easily managed, and well-appointed gentlemen’s daysailer, the company will attract new market audiences by delivering fingertip sailing and plush accommodation.

This shoal-drafted 43-footer will be on the water this fall, and shall prove to be a must-see at any major boat show for any sailor in the market for something fresh and new. Designed by the talented Stephens, Waring & White Yacht Design, the concept exemplifies classic lines and modern performance—as this will be the hinge pin of this marketing campaign. The Sail Plan reveals SWW’s current thinking between the balance of main and fore triangle—a back-stay-less rig and heavily swept spreaders the boat carries a square-topped mainsail of higher efficiency and more stable dynamics under sail. Of course, add the finely tuned sailing platform and onboard hydraulics, push-button sailing and all trimming duty should never be more pleasant! The “Vintage 43” hull and deck will be of corecell and vinylester-infused fiberglass laminates. The fit and finish of the interior will be semi-custom by Rivolta Yachts, leaving the customer to choose colors and trim materials to suit.

While the aesthetic styling of the yacht harkens back to traditional shapes, she also manages to display a fine edge for modern distinction. The superstructure will be characterized by her raked cabin sides of varnished teak that transition softly to a weathered teak cabin top, all of which runs effortlessly aft into comfortable cockpit coamings. The weather decks are to be clad in teak, while the ship’s hardware and Harken deck package in all polished stainless steel adds a clean and classy contrast. If one gets overwhelmed by the rigors of such a spacious and comfortable cockpit, then you may enjoy relaxing on the “sun-pad” situated on the afterdeck! Lounging and sailing will find new grounds for marriage on this elegant yacht.

Learn more about this yacht and its availability by visiting Rivolta Yachts online at http://www.rivoltayachts.com/ . We strongly encourage a visit to the innovative and inspiring website for Stephens, Waring & White Yacht Design at http://www.swwyachtdesign.com/ .

by Paul W. Waring

2/26/09