In 1952, French physician Dr. Alain Bombard set out from the Canary Islands in an inflatable boat; 65 days later, he arrived in Barbados and announced to the world that a healthy man could survive for months on the bounty of the sea alone–by squeezing moisture from fish and turtle flesh using a press and even by drinking small amounts of seawater. While Bombards survival feat and seawater therapy have provoked some skepticism, one of the Frenchmans conclusions remains firmly intact: An inflatable boat is capable of incredible long-distance voyages.
| Billy Black|
| From left: The Achilles LSI-112 has a high-pressure Hypalon floor; the Achilles LSR-104, an aluminum floor; the Mercury 310 Sport, a plywood-panel floor. The BoatU.S. 11.2 offers a choice of three flo* * *|
| Few of us would want to put our inflatable dinghy through such a test, but in fact, the daily rigors of being tender to a cruising boat are probably no less brutal. Ultraviolet radiation, rocky shores, and barnacle-covered pilings are notorious dinghy eaters. Oil, fuel, and other chemicals that we carry in our tenders can wreak havoc with most fabrics. With an eye on durability, we took a look at eight midsize inflatable boats that fold up or roll up for stowage. From five different manufacturers, these boats are just a small slice of whats available in this category, but they present a good cross section of the various types on the market. Along with the manufacturers featured here, the manufacturers of rigid-inflatable boats (RIBs) discussed in “Surviving the Great RIB Hunt” (October 2003) also offer several similar models of roll-up or fold-up boats.
Combining the durability of a fiberglass hull with the buoyancy and stability of inflatable tubes, RIBs make great tenders–but compared with ordinary inflatable boats, when theyre stowed, theyre space hogs. Its no wonder that many cruising sailors, particularly those with smaller boats, still prefer roll-up or foldable inflatables. Some sailboats dont have the space on deck to store a RIB. Other cruisers just dont like the idea of strapping down a rigid hull on deck, where it adds windage, obstructs passage on deck, and is vulnerable to breaking seas.
Although not as durable as a RIB or hard dinghy, a roll-up or foldable inflatable boat is about 30 percent lighter than a RIB of the same length, and it occupies about a quarter of the space when deflated. You must almost always stow a RIB on deck or in davits–a risky move on long ocean passages. By comparison, most roll-up boats in the typical 7- to 10-foot size will pack into a space that measures less than 4 by 3 by 2 feet, so they’re small enough to fit belowdecks or in a large cockpit locker or lazarette.
Compared with RIBs, inflatable boats generally take longer to plane and arent as fast, but theyre no slouches. All of the ones we examined have an inflatable keel tube that runs down the centerline, pushing the fabric bottom out into a V-shape. A well-designed roll-up can be quick and dry and can track almost as well as a good RIB in the same size range. To achieve this performance, however, proper inflation is essential.
If youre willing to sacrifice a little deck space, or if you have a spacious sail locker or lazarette, theres another option: a folding RIB. One of the best-selling inflatable tenders this year, a folding RIB has the rigid fiberglass bottom of an ordinary RIB, but its transom folds down for storage. Both Avon and Bombard (named after Dr. Bombard) make 10 1/2-foot, four-person models that pack into a valise that measures 7 feet by 2 feet by 1 foot.
When choosing a roll-up or folding boat, you need to consider many of the same factors discussed in our October article on RIBs. Youll find a much wider range of products in the roll-up class, but once you nail down your chosen size, your biggest decision will be selecting the type of floor you want. Pricing is competitive; generally, expect to pay more for boats built by U.S. market leaders like Zodiac, Avon, and Achilles, which are backed by experience, extended warranties, and wide dealer networks. Dont be turned off by brochure list prices on these boats, which can be as much as 15 percent above the actual “street” price.
The type of floor you choose will impact the boats assembly time, weight, performance, and, to some degree, durability. Floor design has improved dramatically in the past 10 years, and most manufacturers offer four basic options. From these, cruisers should narrow their hunt to consider either a high-pressure air floor, a panel floor, or a hinged “roll-up” solid floor. Some makers offer the same model of boat with any one of these three choices.
Smaller boats, like the enduring Avon Redcrest, are available with a fourth type: a light and economical wooden-slat floor. This style makes a fine tender for going back and forth to a mooring, but to expect it to haul fuel, water, and provisions over long distances or to endure the abuses of long-term cruising is a bit like counting on a VW Beetle for family vacations–it can be done, but only with considerable compromises.
The Air-Floor Option
If you intend to roll up your boat often, you’ll want to look into boats with high-pressure air floors. Usually less than 2 inches thick, a high-pressure air floor remains rigid thanks to 11 psi of pressure (versus about 3.5 psi for the hull tubes) between the top and bottom fabric panels. Thousands of high-tenacity fibers drop-stitched between the two panels help the floor keep its shape. While many manufacturers prefer Hypalon–famous for its resistance to abrasion, ultraviolet rays, and chemicals–in hull tubes, PVC is the most common material for high-pressure air floors (see “Hypalon vs. PVC,” a sidebar to “Surviving the Great RIB Hunt,” October 2003).
The advantages of an air floor are its light weight and ease of use. You can roll up or unroll your boat in a pinch without having to remove or install the floor. Fitting a panel floor can be a hassle with some designs, particularly if youre working on the water or on the deck of a sailboat. Although air floors have revolutionized the roll-up boat, they do have drawbacks:
Inflation: To perform properly, these floors need to be fully inflated to the rated pressure. This means youll inevitably have to do some pumping–usually in the morning–to compensate for the expansion and contraction of air caused by temperature changes, and in hot, sunny climates, youll want to watch for overinflation.
Stiffness: An air floor generally isnt as rigid as a panel or hinged solid floor. Because the floor is what keeps the inflatable keel down to give the V-shape to the hull, an air-floor model of the same boat can have a slightly shallower V than a solid-floor boat.
Resistance to abrasion, puncture, and chemicals: Even with the high-tech coatings on todays fabrics, an inflatable floor cant hold up to the punishment a solid floor is able to endure.
Repairability and price: Repairing a high-pressure floor isnt any trickier than normal tube repair, but its generally more expensive than dealing with a broken plywood panel. Check the price of a replacement air floor when you compare models.
Reality: Be honest about how often you roll up your dinghy and store it below. If you find you spend more time towing your dinghy or stowing it, fully or partially inflated, on deck, the durability of a solid floor might offset the lightness and ease of assembly an air-floor affords.
Achilles LSI-112: The LSI-112 is one of two boats we looked at with both Hypalon air floors and tubes, a feature of all five models in the Achilles’ line. Achilles has been using this material in its air floors for five years, so it has a good handle on what works. Hypalon’s renowned resistance to chemicals will be reassuring when making fuel runs. Like most manufacturers, Achilles has been gradually increasing its tube size, and the 18-inch-diameter tubes, combined with the ample beam, makes for a boat that feels big and offers plenty of interior volume. The LSI-112 is one boat that will easily fit into the supplied storage bag, which can’t be said of every roll-up. Achilles offers a 10-year warranty on its Hypalon fabric and a five-year warranty on its seams.
Aqua Dutch 310: This is a competitively priced boat with some nice design features. Selling in the United States mostly at boat shows and over the Internet, this small company doesnt offer much in the way of dealer and service network, but we liked the looks of this boat, which is aimed at the cruising-sailor market. You can specify either Hypalon or PVC tube material and either a plywood or a more substantial solid-fiberglass transom, the choice being determined by how much youre willing to spend.
We looked at the top-of-the-line model, which featured the rugged, solid-fiberglass transom and tubes made from Orca 828, a Hypalon/ neoprene composite fabric guaranteed for five years and produced by Pennel (www. pennelindustries.fr). The PVC air floor has zigzag-pattern stitching that looks nice and also acts as a kind of nonskid. Should the hull outlast the floor, a new floor costs just $195, far less than replacement floors for some other brands. At that price, it might be worth having a spare.
Avon Rover 340: Also available with a roll-away solid PVC floor, the Avon Rover 340 delivers the quality you’d expect from one of the longtime leaders in this field. The British subsidiary of Groupe Zodiac has recently updated the popular Rover series, which features boats from 8 feet 6 inches to 11 feet 2 inches long. The 340 is the biggest boat in this line. Its internal oar-storage system is the best arrangement, and though the rubber, snap-in oarlocks take some getting used to, they’re integral to the tubes and won’t get lost.
The thick rubbing strakes, rugged attachment points for lifting handles and towing bridles, and well-reinforced transom reflect a boat that’s built to take some punishment. With an extensive service network, Avon can truly stand behind its 10-year fabric and five-year seam guarantee.
Mercury 310 Air Deck: Available in either PVC or Hypalon, the Mercury 310 Air Deck is representative of Mercurys commitment to improving its product line and keeping pricing affordable. One notable change over earlier Mercury boats is the downward flare of the end cones to provide more buoyancy aft and gain performance with heavier four-stroke engines. Mercurys tests show that the new design has decreased the time it takes to bring the boat to a plane by at least 10 percent. Third in size in a line that ranges from 7 feet 11 inches to 11 feet 2 inches, the 10-foot-2-inch 310 has dual stations for the wooden thwart (a second thwart is optional), a rugged rubrail, and tube-top oar stowage that keeps oars in place, even at high speed. We liked the efficient dual-action hand pump with a built-in pressure gauge–the pump is one of the best of the group. Several coats of epoxy protect the wooden transom, a weak spot on many inflatable boats.
BoatU.S. 11.2 by Severn Boats: This 11-footer is the other model we looked at with a high-pressure Hypalon floor. Also available with either a roll-up hinged PVC floor or an interlocking plywood-panel floor, its the only boat in this group that offers the option of switching between three floor types. Because the floors are interchangeable, you could choose to carry more than one type of floor and switch them to suit the circumstances–air floor for inland excursions by car, wood floor for fishing the reef off Belize. The boat is made of Hypalon (Orca 828) and is sealed with double-butted seams, which use fabric glued along the inside as well as the outside of each seam to prevent any failure. The boat lacks the sheer of the others in this group, but the V is slightly deeper. Because of the selling power of BoatU.S., these boats are budget-friendly.
Zodiac C 340 FR: An inflatable-boat leader, Zodiac has introduced a number of novel features in its 2003 fast-roller Cadet series. The most notable is what Zodiac calls its Active-V, which improves upon the conventional high-pressure floor by combining the floor and keel into one unit. This creates a more positive V-shape and allows you to inflate the floor and keel at the same time through a single valve. The C 340 FR was the only air-floor model that featured both a self-bailing drain that could be opened and closed from inside the boat and a four-point tie-down for the fuel tank. The webbing handholds and a padded two-position thwart make for a more comfortable ride. Zodiac is the only inflatable maker in this group that uses PVC fabric and thermowelded seams, which are guaranteed for five years.
A solid floor is hard to beat as an economical surface that can stand up to the routine abuse cruisers dish out. There are two basic varieties of solid floors; each has its advantages. The most familiar type is probably the panel floor, which features four or five interlocking plywood–or, rarely, aluminum or thermoplastic–panels that are supported along the outside rails with grooved stringers. Because you have to disconnect the panels each time the boat is deflated for stowing, this is the most difficult type of floor to fit. Installation is best accomplished on a flat surface, which isn’t always easy to find on a sailboat. Some users first launch these boats partially assembled, then take them ashore to install the floor. On some models, you must stow the floor panels separately from the boat because they’re too large to fit in the same bag.
Panel floors are generally heavier than any other type of floor, and the plywood floors, like anything made of wood, can require a regular coat of paint or varnish. Over time, wood floors can warp. Some manufacturers paint the panels with a hard epoxy coating that tends to hold up better than varnish. The benefits of a panel floor are its economical price, its strength, and its resistance to abrasion and puncture. Should a panel break, a do-it-yourselfer with some basic tools can easily make a new one.
The roll-up solid floor has hinged slats, usually aluminum or plastic, that roll up as a single unit. A hinged floor is slightly less rigid than a panel floor, but its simpler to install and stow. Like an air floor, the roll-up floor can usually be rolled up with the boat for stowage. Assembly is typically a matter of unrolling the boat and inflating it.
Foldable Hard Floors
Achilles LSR-104: Also available in a 9-foot-6-inch version, this 10-foot-4-inch model uses a hinged aluminum roll-up floor to provide a strong, rigid platform that’s more portable and lighter than traditional wooden panels and almost as easy to stow as an air floor. You can leave the polyurethane-coated aluminum floor in place when you roll the boat up; when the boat’s assembled, the floor, which has a nonskid surface, provides reliable footing when boarding and plenty of support for carrying cargo and loading and unloading.
Available in either white or gray, the LSR-104 has substantial interior volume for a boat of its size, and it features the high quality all-Hypalon construction that you expect from Achilles. The relatively low list price makes this boat a good value.
Mercury 310 Sport: Using interlocking, painted plywood-floor panels supported with a slide-on aluminum stringer, the Mercury 310 Sport offers simplicity and durability at an affordable price. Made using coated PVC fabric with heat-welded seams that are both guaranteed for five years, the 310 Sport has three separate hull chambers (plus the inflatable keel) for added security in the event of a puncture.
Like the boats in Mercury’s Air Deck line, the boats in the Sport line–from 6 feet 7 inches to 11 feet 2 inches in length–have redesigned end cones to provide more buoyancy aft and quicker planing. The panel floors come in six labeled sections that you can store in the same bag as the boat when it’s deflated and rolled up.
Although a folding RIB is technically a different breed when viewed in relation to the other boats in this group, we’ve included it here because it shares many of the same features and will appeal to owners of smaller cruising boats. This type of boat delivers RIB performance and durability in a boat that fits into a bag the size of surfboard. Anyone with a little extra deck space, a big lazarette, or an unoccupied pilot berth who’s looking for a roll-up boat might want to consider the advantages of a folding RIB.
Bombard AX 500 Compact: The Bombard AX 500 Compact combines thermowelded PVC tubes with a lightweight, injection-molded fiberglass hull. The injection molding helps minimize weight by ensuring a consistent resin-to-fiber ratio in the fiberglass. Both Avon and Bombard are subsidiaries of Groupe Zodiac, and for those willing to pay about $150 more for Hypalon fabric, the same hull and design is used in Avons Hypalon 310 Rover Lite RIB. Assembly is simply a matter of unrolling the boat and pumping up the tubes. For stowage, the boat fits easily into a nice-looking zippered bag. Because of its light weight and slippery, efficient fiberglass hull, the boat will perform quite well with less than its maximum-rated 9.9-horsepower engine.
If, after all your shopping, you still cant decide which floors best for you, consider this: For pure convenience and light weight, an air floor is hands-down the best choice; for durability and simplicity, the wooden-panel floor is the way to go; for a compromise between the two, a hinged roll-up floor is the ticket.
As for me–a dyed-in-the-wool hard-dinghy man–if I went the inflatable-boat route, Id choose a plywood-panel floor. For most people, this is a dying breed, but for me, the assembly hassles are offset by having something very durable that I can fix anywhere myself. Then again, if I had enough room for one of those folding RIBs. . . .
Darrell Nicholson is Cruising Worlds senior editor.