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Unsinkable boats, exceptional safety

A look at five builders whose boats won’t leave you in the water

A look at five builders whose boats won’t leave you in the water

A family fishing on the Mississippi River hits a submerged obstacle and punches a hole in the bottom of their center console. The father drives the boat 30 miles back to his marina.

A 31-footer bursts a hose 28 miles off one of the Southern states; the boat is at risk of flooding. The skipper brings it back to shore under its own power, without further incident.

Both of these cases involved Boston Whaler boats, and the owners were able to help themselves out of trouble, at least in part, because each was in an “unsinkable” boat, with a foam and fiberglass hull.

Unsinkability is nothing new. Boston Whaler’s pioneering foam-filled boats debuted more than 40 years ago, and their unsinkability helped sell them. Plus, Congress and the Coast Guard mandated certain standards of level flotation and carrying capacity in monohull boats 20 feet and under back in the 1970s, which has saved thousands of lives.

What is new is that unsinkable technology is finding its way into larger boats. Using sophisticated design tools and the latest in materials — from foam to carbon fiber — builders are producing so-called unsinkable vessels larger than 30 feet. There are several unsinkable powerboats in the 26- to 28-foot range, with one of the largest around 32 feet. (The 34-foot Boston Whaler Defiance was among the builder’s stable of unsinkable powerboats; it is no longer built but can be found used.) On the sail side, ETAP Yachts, a European yacht builder, is selling a 37-foot unsinkable sloop in the United States, with the proven claim that it can be safely sailed in most conditions while swamped. ETAP plans to bring a 41-footer to the U.S. market next year.

And builders say they’re continually tweaking the construction methods as they seek not only to perfect unsinkable technology, but to incorporate it into even larger boats, with the next goal being 40 feet and larger.

“People follow a natural progression from smaller boats to larger ones,” says Nick Craven, sales and marketing coordinator for McKee Craft, a 38-year-old North Carolina powerboat manufacturer that claims its boats won’t sink. “So our focus is on going larger.”

Concern for safety

Boatbuilders say customers — whether anglers or family boaters — are united in their concern for safety.

“Unsinkability is increasingly important to both the novice and the experienced boater,” says Peter Truslow, president of Florida’s EdgeWater Power Boats. “As far as the less-experienced boaters are concerned, it’s a conversation that starts fairly early in the buying process. They’ve heard about boats capsizing or sinking, and they want to avoid that experience. The knowledgeable offshore boater or fisherman has maybe already gone through a scary experience, so they know what can happen and they’re being cautious.”

Veteran Florida boatbuilder Bob Dougherty, who helped get Boston Whaler off the ground four decades ago, agrees. “Once you get out there, once you watch that depth sounder drop off, then you start looking for things to make you and your boat safer,” says Dougherty, CEO of powerboat builder Everglades boats of Edgewater, Fla. “The discerning boater has an appreciation for what it’s all about.”

“Unsinkable” has become a buzzword, and there’s nothing like an on-water demonstration to show it off. Boston Whaler last year initiated its “Unsinkable Legend Tour,” in which an 18-footer that had been cut in half was launched at locations around the country to demonstrate Whalers’ ability to stay afloat and run under the most extreme conditions. It’s been so popular the company plans to continue the program.

ETAP Yachts, a 34-year-old Belgian builder with some 7,000 sailboats sold, swamped one of its boats and took it across the English Channel under sail to make its unsinkable point. It later repeated the feat on Chesapeake Bay.

“There’s a lot to think about when you’re offshore and things are getting nasty, or a situation develops,” says Truslow of EdgeWater. “How reliable is my engine? How strong is my hull? How seaworthy is the boat in a squall? With an unsinkable boat, there’s one thing you can cross off your list: At least you have a hull that won’t drop out from underneath you.”

Certainly, an unsinkable hull is no guarantee of survival, but it can offer more than just peace of mind. In a time of crisis, it can give boaters a chance to help themselves, says Dane Somers of Sail-La-Vie, the North American distributor for ETAP Yachts. “It’s positive flotation, and it gives you something to hang on to,” he says. “That might give you the chance to signal for help or possibly make repairs, and with our boats, maybe put up a sail and make your way to safety.”

Methods and materials

Foam and fiberglass are the most common materials used to keep boats afloat. (Thermal or rotomolded plastic also is used.) There are subtle differences in how the companies engineer their boats and how they use the same basic materials. Here’s a summary of how five builders — Boston Whaler, EdgeWater, McKee Craft, Everglades and ETAP — build unsinkability into their boats.

Boston Whaler uses its own Unibond construction process to create a foam sandwich with fiberglass skins. First, the hull and deck are laid up and joined together. Before the resin cures, a liquid foam is injected into the space between the two, and a chemical reaction takes place.

“The glass and foam chemically bond to each other as they cure,” says Dean Kuti, Whaler sales and marketing product coordinator. The result is a virtually one-piece deck/hull filled completely with foam, with the foam-fiberglass sandwich itself providing most of the structural strength.

Boston Whaler, Edgewater, Fla. Phone: (800) 942-5379.

McKee Craft lays up its boats’ inner and outer hulls, and allows them to cure fully, says Craven. “We then hand-foam around fishboxes and other components, bond the two together, and put the hollow form into a foaming jig,” he says.

Foam is injected under pressure and channeled to every corner of the structure, filling it entirely. The combination delivers superior flotation, and the foam-fiberglass blend also provides structural stability, says Craven. “The foam acts as a structural component and eliminates the need for a stringer system,” he says.

McKee Craft, Fairmont, N.C. Phone: (910) 628-0926.

EdgeWater has just developed a new construction method that takes advantage of advances in computer-aided design technology. “We use a CAD-designed, preformed foam stringer that’s installed immediately after we glass the hull so that it makes a primary bond,” says Truslow. “Then it’s wrapped in fiberglass, and the whole grid structure is filled with foam. In fact, most of the boat below the deck is foam-filled.”

EdgeWater also “post-foams” (after the deck and hull are bonded together), on boats 20 feet and larger, for additional stability above the waterline in the event the boat fills with water, according to Truslow.

EdgeWater Power Boats, Edgewater, Fla. Phone: (386) 426-5457.

Everglades uses a patented process where the hull and deck are laid up over three premolded foam cores in hull, deck and transom shapes. Once the pieces are ready, the entire boat is then vacuum-bagged. The result is a virtually one-piece unit, says Dougherty, who developed the so-called RAMCAP (rapid molded core assembly process) system. RAMCAP eliminates “blind foaming” — where foam is injected into a closed cavity — allows more control over the quality of the foam core, and gives excellent adhesion, according to Dougherty. It’s currently used on Everglades models up to 24 feet.

Everglades Boats, Edgewater, Fla. Phone: (386) 409-2202.

ETAP starts with an outer hull that’s laid up the same as in a conventional boat, according to Somers. “You could sail an ETAP with the outer hull alone,” he says. An inner hull is then bonded to the outer one, and foam is injected into specific areas in the spaces between the two. “We design the hull, keel and sail plan first, and then do flotation calculations, and design the interior,” says Somers. “The foam not only serves as flotation, but also channels water to particular areas in the hull, so it’s used only in certain places. Its distribution is critical to keep the boat level and stable. For example, there’s no foam down low in the boat, because you want to keep the water [in the bilge] low and centered.”

ETAP USA, Sail-La-Vie, Freeport, Maine. Phone: (866) 382-7872.

ETAP Marine (dealer, Rhode Island to New Jersey), Summit, N.J. Phone: (908) 918-1886.

On the horizon

Why isn’t everyone jumping onto the unsinkable bandwagon? For one thing, it’s not easy to build boats that won’t sink, according to builders. “It’s not conducive to volume production because it’s not a simple process,” says Craven of McKee Craft. “The boats stay in the molds a long time, then there’s the jig and the whole foaming process. It takes a lot of attention from a manufacturing standpoint.”

Foam also takes up space on a boat, and that’s critical, especially in cabin boats where room below is a premium. The ETAP 37s requires 6 to 7 cubic feet of foam, and designers have to find room for it in the confined space between the boat’s hull and liner, says Somers, the North American distributor. “That’s a lot of room, and it’s a real challenge,” he says.

Building an unsinkable boat also is more costly, which means the end product is more expensive, too. “You use more materials, more labor, and you spend more time engineering,” says Somers. “Then you have to look at the cost benefit: Is this a value that you’re adding that the customer is willing to pay for?”

The builders say the answer is yes.

ETAP is busy expanding its fleet of unsinkable boats and plans to add powerboats soon. “With our [construction] method, we’re unlimited by size,” Somers says. “Right now, we’re working on a 46-foot sailboat, and we plan to introduce a 36-foot and a 46-foot motoryacht soon.”

McKee Craft also is adding models. “We have a couple of new, bigger boats that will be ready for the 2005 season,” says Craven. “The idea of a walkaround or a cuddy cabin and some larger sizes has come up.”

EdgeWater is considering larger unsinkables to keep current owners of 22- to 26-footers in the family, Truslow says. “We’re looking to develop new, easy-to-use technology in larger boats,” he says. “We’re using a carbon-reinforced grid now, and we’re looking at coring, too. Air chambers may be added to the technology — that may be another way of doing it.”

Dougherty is optimistic that RAMCAP will allow him to expand the Everglades fleet with bigger models, too. “Is there a limit? I don’t think so,” he says. “We have some larger stuff in the works. We’re looking at bigger boats in the next few years.”

Whaler says it has no immediate plans to add to its 17-boat Unibond lineup, which goes up to 32 feet, says Kuti. But that doesn’t mean the unsinkable-boat pioneer is standing still. “We’re looking at the technology on a continuing basis,” he says. “For bigger boats, we need to take a look at new ways to bond the liners, new grid systems, all the elements that go into it.”

The demand is there. “Unsinkability is huge,” says Craven. “A customer with a family called the other day and confessed that the unsinkability of our boats was the deciding factor in their choice of a McKee Craft. And that’s not so unusual anymore.”