Features May 1, 2000 Issue

Life Rafts: The Good, The Bad and The Ugly

Part 1—Extensive in-water tests and examinations of 25 rafts find considerable differences in stability, comfort and safety equipment. Here’s help in identifying the most important features.

by Douglas S. Ritter

This photo of the life rafts tested shows the
variety of shapes and canopy styles, plus one
vs. two tubes.

With lives at stake, we expect manufacturers of safety equipment to value our lives, and those we care about, as much as we do. Unfortunately, that isn’t always the case, as we discovered yet again when we evaluated life rafts. Mind you, all the rafts tested could save your life if everything goes right, but we’re inclined to believe that is not likely always going to be the case, otherwise why would you bother with a life raft in the first place?

We evaluated three inshore, eight coastal and 14 offshore life rafts, in four- or six-person capacities, from nine manufacturers: Crewsaver by Eurovinil (Italy), DBC Marine Safety (Canada), Givens Marine Survival (U.S.), Plastimo (France), Survival Products, Inc. (U.S.), Switlik Parachute Co. (U.S.), Viking Lifesaving Equipment (Denmark), West Marine by Zodiac (France), Winslow LifeRaft Co. (U.S.), and Zodiac International (France). Avon declined to participate, citing the unavailability of their completely revised product line with manufacturing just under way in Hungary. RPR Industries, which formerly manufactured the Givens rafts and now is manufacturing a similar raft on its own, declined, citing pending legal issues involving Givens. Eastern Aero Marine also declined and RFD/Revere and BFA failed to return our calls or e-mails.

Part 1 covers our general findings. Parts 2 and 3 report our findings with coastal and offshore models.

Performance tests were conducted in a wave pool to ensure consistent conditions. Volunteers attended from throughout the U.S. and Europe. They ranged from unsuspecting “life raft virgins” who had never been in a life raft before, to experienced survival instructors. Following three days of exhausting in-water work, we conducted detailed evaluations of the rafts and their survival equipment.

Two volunteers developed rashes covering their exposed skin. It was unclear whether this resulted from an allergic reaction or from the abuse of testing. If this is a concern, request a sample of material to test before purchasing.

The evaluations were conducted in cooperation with Equipped To Survive (www.equipped.org). The United States Coast Guard sent two representatives, their senior rescue swimmer, Master Chief Keith Jensen, and Lieutenant Commander Paul Steward from the Office of Search And Rescue.

You can't expect a small valise or canister weighing from 12 to 100+ pounds to afford the luxury of a yacht. The option of last resort, a life raft should be capable of delivering its occupants to safety, even through weather and seas that may have contributed to the loss of the mother vessel. That’s a lot to ask of anything, let alone some inflatable contraption made of fabric and little else.

The rafts tested ranged widely in price, features, and capability. When all was said and done, our overriding concern focused on capability—would it save our lives?

As we spent hours, days and weeks with these rafts, a related concern came to the fore. The raft must be designed and equipped to take care of the survivor; it should demand little or nothing of the survivor, who may be unable to do much on his or her behalf. Everything should be obvious and intuitive to survivors who most likely have no survival training.

A life raft is an integrated system in which the performance of individual features, or lack thereof, can significantly affect overall performance. The devil is often in the details.

Choosing a raft can be difficult. The selection is confusing and the terminology often doesn’t clarify issues. With little in the way of standards for non-commercial rafts, manufacturers can pretty much make whatever claims they want to.

Criteria For Evaluations
In evaluating the rafts we were concerned with a number of attributes: ease of deployment and operation; seaworthiness and stability; ease of entry, both from the vessel and the water; protection from the sea and elements; functionality; livability; comfort; survival equipment selection and quality; and of course, price. Some of these are more critical than others, but all have a bearing when making a choice.

Size Does Matter
The space available to each survivor has a huge impact on livability. SOLAS/USCG-approved rafts use, as one measure, a minimum of 4 sq., ft. per person. While popular opinion seems to be that non-approved rafts often don't meet this standard, virtually every raft we reviewed did, though only a few exceeded it by any significant amount. Winslow's Ocean Rescue took top honors with half again more space per person. While configuration can make a difference, any way you slice it there isn't much room. Think sardines. Lay open this publication on the floor and multiply it by three. Imagine spending a few days in that space.

If you can afford a few extra dollars, pounds, and a few inches, seriously consider going up one or even two sizes, but only if you purchase a well-ballasted raft. For example, if you need a four-person raft, upgrade to a six-person, which is essentially what Winslow has done with its Ocean Rescue model. In a raft with minimal ballast, it is better to stick with the rated capacity, maximizing the ballast effect of the survivors.

Pick A Shape
Rafts come in three basic shapes: round or nearly so (5-, 6-, 8-, 10- and 12-sided), square, and elliptical or boat shaped (rectangles, and elongated heptagons and octagons).

All other things being equal (they rarely were in any of our raft evaluations), a square or elongated raft may provide more comfortable seating with survivors side-by-side, alternating one way and another, though things can get messy at the ends in some rafts. In all but the most spacious round rafts, everyone’s feet generally tangle in the middle when stretched out, which can get uncomfortable.

A raft’s drogue (called a “sea anchor” by some) is an important and often under-rated element in the stability and seaworthiness of all rafts. As a raft starts to come out of the water a drogue can provide significant added resistance to capsizing. For a square and especially a boat-shaped raft, however, it is more critical. A boat-shaped raft, running with wind and waves, is probably somewhat less likely to overturn, in this case end-over-end, than a comparably sized and ballasted round raft, all other things being equal (again, usually they are not).

Unfortunately, drogues are often lost in heavy weather. If a round raft loses its drogue, it may carousel, but it generally has no inherently less stable configuration. Lose the drogue on a boat-shaped raft and it is likely to quickly turn broadside and settle in a wave trough, as would a boat without steering. Unless the ballast compensates, it is then more likely to capsize in conditions that might otherwise not cause a problem.

Multi-sided equilateral rafts, especially those with six or more sides, can have a structural advantage over round or elongated rafts. The short-coupled reinforced mitered joints can provide significant added rigidity, which was evident reviewing video tapes of our tests.

One Tube Or Two?
Another obvious distinction between rafts is whether they have a single tube for floatation or if they use two stacked tubes. Many Coastal rafts have only a single tube. The difference in freeboard is significant. In rough weather, the more freeboard you have, the better. With double tube rafts, larger tubes provide greater freeboard and more reserve buoyancy.

Twin tubes also offer a much more supportive backrest; the single tube rafts were deemed much more uncomfortable. Also, higher sides are necessary to brace oneself against the violent motion of the raft in bad weather.

Inflatables, while pretty darn tough, are still subject to puncture by any number of means. Even in closely supervised training, rafts are often punctured.

We feel strongly that there must be means to ensure that if there is a puncture, then some buoyancy remains. Whether by having multiple tubes or by dividing up a single tube internally, puncturing one buoyancy chamber should not sink the whole raft. The DBC and Plastimo coastal, and all three inshore rafts, were deficient in this regard.

However, buoyancy doesn’t necessarily mean you’ll stay dry. In most single-tube rafts the tube is divided in half by vertical bulkheads. If one chamber deflates, survivors in that half are going into the water and everyone is going to get wet. You are left with a half circle of tube open to the water across the diameter, like a donut broken in half. Even a partial deflation presented problems for our volunteers, swamping the raft.

Switlik's CLR6 USCG Coastal Mk II addresses this problem with internal sleeves that expand to fill the deflated half of the raft. This leaves the entire raft inflated to approximately 50%, which can be topped off without first repairing the puncture. In our tests, however, it wasn't enough to keep the raft from being partially swamped. Better, but not nearly as good as two tubes.

The practical advantages of single tube rafts are weight and space savings. They generally cost a good deal less, though not just because they are single tube designs.

Deploying The Raft
As soon as we started unloading and moving the rafts around the issue of weight was raised by the volunteers. Even with two people, dealing with some of the heavier rafts was a burden. The critical question became, “How could one possibly deploy a heavy raft under trying conditions, if exhausted from fighting a storm, or if short-handed?”

The weight and volume of the raft is affected by its capacity, its design, additional features, and the materials from which it is made. Other things also contribute to overall weight. A canister is generally heavier and more bulky than a valise. The selection of survival equipment also can make a huge difference in overall weight.

Being unfamiliar with exactly how each raft would be deployed, the virgins often had some difficulties caused by either misunderstood directions printed on the raft or difficulty performing the inflation procedure. Neither written nor pictorial instructions alone seem to be entirely adequate. Some of the English translations provided a few laughs.

If possible, attend a deployment demonstration. The Zodiac and West Marine rafts came with an instructional video, which while not great, were better than anyone else provides. At the least, take time to review the deployment instructions ahead of time, when you can concentrate on them without distraction.

The painters (mooring lines), which are tied to the boat to prevent the raft from being blown away, varied in length from a much too short 22'. (Plastimo Coastline), to a possibly excessive, 125'. (Switlik CLR6). SOLAS calls for “15 meters” or about 50'. Painter failures after deployment have resulted in rafts being lost before boarding. Many suggest that the weak link in these painters, which prevents the raft from going down with the vessel, should be stronger than the 500 lbs. mandated. Trying to haul in a raft at the end of a 100+' line, against the seas and wind, can take time and strength that aren’t available. We are not convinced that painters in excess of 50' are necessary or desirable.

The painter should always lead directly to the primary boarding station. In some rafts, the West Marine Offshore, for example, it leads to the alternate boarding station with less capable aids. In others, the Switlik MD-2 for example, it doesn’t lead to a boarding location at all and the instructions, once you reach the raft, don’t make it clear which way to go to the primary boarding station.

While only two rafts inflated upside down, it is always a possibility. Only the Givens seemed to have any significant self-righting tendencies when empty. With no wind or heavy seas to deal with, righting was relatively easy for most, but it was obvious that under real world conditions some would be much more difficult to right than others due to inadequate aids, the lone handhold of the DBCs and Viking being good examples.

More critically perhaps, righting instructions were often woefully deficient; volunteers ignorant of the proper technique weren't helped much. At night, for most of the rafts, forget it. The Winslows, with excellent righting aids and an exclusive “righting locator light,” were applauded.

All Aboard!
How easy will it be to jump into the raft from the boat? The Winslows and the Switlik SAR Mk II have large canopy openings, making boarding easy. Others, Givens and DBC for example, have small openings that would make it more difficult and potentially dangerous.

Boarding from the water, the effectiveness of the boarding aids is absolutely critical. Some rafts with minimal aids and little more than a few loops of line for assist—Givens, Zodiac, and Viking—were virtually impossible for some volunteers to board without assistance, which may not be available. Without considerable upper body strength, you're in trouble. Short and bottom heavy volunteers especially had difficulties, but anyone who is injured or exhausted from fighting a storm could have difficulty. A few rafts made it relatively easy, including Winslow with its ample outside and inside ladders, stirrups, and grab handles; Switlik's “step” on most of their rafts; and the West Marine Offshore and DBC Swiftsure Global with their inflatable “ramps.”

Staying Sunnyside Up
The stability of the raft is critical. Survival accounts are filled with tales of rafts capsizing again and again, usually losing precious supplies and sometimes lives. The 1998 Sydney-Hobart Race was but the latest well-publicized example.

Ballast is your primary means of preventing a capsize. From a practical standpoint, ballast in a raft is limited to the people and equipment in and on the raft and some means of retaining water below the raft to counteract the tendency to capsize as it lifts out of the water.

Experience shows that raft occupants are of limited value in terms of ballast, especially if there are fewer than the rated capacity. What happens if you have a six-person for your for-person crew, but only two of you make it into the raft? A raft bottom even slightly raised off the water by wave action can be easily caught by the wind and the raft capsized in an instant…unless something either blocks or opposes the force of the wind.

Ballast effectiveness is determined by the capacity of the water retention devices, their configuration, and their placement. All the non-U.S.-manufactured rafts use similar, marginally effective ballast systems--V-shaped bags hanging below the raft. Capsizing them was a trivial matter. U.S. manufacturers provide more capable, higher capacity ballast systems, ranging from box-shaped bags on the Winslows and Switliks to the unique Switlik “toroidal” ballast on its SAR MkII, and Givens' “hemispherical” design. Another consideration, particularly with regards to boarding, is how quickly they fill with water. With the exception of Winslow and Givens, all had weights to assist in rapid filling, though results were mixed.

Is there such thing as too much ballast? Possibly, in the sense that “excessive” ballast may compromise other seaworthiness-related characteristics, but better too much than too little as far as we're concerned. In our opinion, the non-U.S. entries and inshore rafts all were deficient.

What A Drag
As noted earlier, the drogue is an integral part of the life raft system. To function properly as a stabilizer, to slow drift and help counter capsizing action, it must be strong enough to not be torn off in heavy seas, provide sufficient drag to be effective, offer adequate rode length and at least a single swivel to cope with heavy seas, must not tangle and must not collapse when subjected to repeating wave action. Two styles are common, the conical and the "parachute" or "hemispherical” style. Both have their pros and cons, but if properly designed, each can do the job. In our tests, Winslow's hemispherical drogue was tops in drag. The best of the rest offered about half its performance (Viking, DBC, and Winslow conicals and the West Marine chute). The remainder we deem inadequate.

Only Winslow and West Marine use swivels on the drogue. These are essential to eliminate twisting of the rode, which is believed to be the primary cause of failures. Only the Plastimo Coastline lacked a drogue, but some of the rodes were too short, as little as 16.5' for the Switlik CLR6. None of the drogues on a short rode performed well—we consider 75' the minimum and double that wouldn't be too much. We also prefer the heavier line used with many of the drogues as opposed to lightweight parachute line found on the Winslow, Givens and many of the Switliks.

While some manufacturers require the survivor to deploy the drogue, we prefer self-deploying drogues—one less thing for the survivor to worry about. The drogue should orient the raft so that the entry(ies) and vulnerable portions are sheltered.

A weathertight canopy is essential in adverse weather conditions. All the life rafts ,excluding the inshore platforms, were equipped with self-erecting canopies that use an inflatable arch or arches for support. No tester had a single good word to say about the single arch canopies. “Better than nothing” about summed up the sentiment. Particularly with single tube rafts, but even with double tubes, headroom is seriously compromised—sitting hunched over gets extremely uncomfortable. The twin- or tri-arch designs on the Givens, West Marine and Winslow offshore, and Switlik's MkII rafts are vastly superior.

A bright orange canopy is vital for being found, but SOLAS requires a blue interior for its supposed calming effect. Many canopies were either white or orange inside, turning everyone inside a sickly orange shade. On the other hand, they were at least brighter inside. With the exception of the Winslows that were fitted with unique clear viewing and ventilation ports, the others’ opaque blue interiors became black holes when closed up. One volunteer said of the Givens that it “felt like I was locked in a crypt.” Some rafts were equipped with an interior light, which we feel is essential, but for the most part even those were only marginally effective. The Winslow "viewports" were widely lauded, both for contributing to a psychologically more comforting environment and as a potential antidote to seasickness, a serious concern for survivors.

Wet and Cold Leaks
A canopy that leaks is not nearly as comfortable or effective as one that really keeps the weather out. Two issues arise here—effectiveness of the closure system on the canopy openings and ease of use. All the closure systems are a compromise, but overall we prefer ease of use that doesn't require much manual manipulation. Digital dexterity is one of the first things lost as a result of exposure.

Zippered closures, at least those with large zippers and helpful zipper pulls, such as Winslow's and Switlik’s, are the easiest to use and fastest canopies to close up. Closures using cloth ties can be difficult in cold weather. We had problems with some of them, such as the Givens, even in calm and warm conditions. Tie systems are inevitably less waterproof than a well-designed zipper system with good storm flaps, but exposed zippers, such as those used on some of the Switliks, leaked water.

A good entry design allows for ventilation at the top as the entry is closed up, not down. Switlik and West Marine are good examples of this. Winslow counters with an entry that zips down, but is equipped with a double acting zipper. The opening viewports provided in all but their base models were very popular with the volunteers, though they lack weather protection. Viking, Plastimo and Zodiac provide few options except closed or open, a deficiency well noted by the testers.

Insulated Floors
An insulated floor is important, even in temperate waters, though it is optional on most rafts, unavailable on some. Zodiac and West Marine use a thin layer of foam with a reflective surface integral with the floor. The effect of UV on the reflective surface in the tropics gives us pause, and the foam was ripped up in places even from our short test period. The Plastimo Offshore+ had a tied-in foam sheet that was a real nuisance. Winslow, DBC and others offer integral inflatable floors, some with reeds, others without, a less desirable design. Crewsaver, Viking and Switlik offer drop-in inflatable floors, much like an air mattress. Switlik also offers a drop-stitch drop-in inflatable floor. This floor becomes an almost rigid structure 2.5" thick, easily the most comfortable of the options, though they are quite heavy. In our experience, the Zodiac foam floors aren't as effective or robust as the best inflatable floors, with Winslow's and the drop-stitch from Switlik leading the pack.

The selection of raft and survival equipment included with each raft ranged from utterly deficient to reasonably well equipped. Inshore and coastal rafts especially were shortchanged. Many didn't include the most basic signaling device, a signal mirror. Often the quality of equipment was also questionable. You'd be in the dark, for example, if you relied on DBC's choice of flashlight—three out of three were defective.

With the exception of the U.S.-influenced West Marine rafts, we were particularly unimpressed with the raft repair supplies used by the non-U.S. manufacturers. The patch kits all suggest you first dry the materials to be bonded—hardly welcome instructions in a wet life raft! Most suggest waiting a period before re-inflating. Don't even think about using them below the waterline. The wood, rubber and plastic plugs are effective as a stopgap measure, but not great for long-term use. All the U.S. and West Marine rafts included mil-spec raft repair clamps that are very effective.

Generally speaking, you'd best plan on supplementing the raft's equipment with your own. The less expensive the raft, the more equipment you'll need to provide yourself.

Where To Put It?
One of the most difficult questions is whether to buy a container or valise, and where to put it. The smaller the boat, the more pressing the problem.

A container generally means finding space where it will least be in the way. Only of late are some boatbuilders, mostly of larger boats, providing a dedicated space for a life raft that also aids in launching it. The most common spot, otherwise, seems to be on deck before or behind the mast. The downside of this location is accessibility. If everything has gone to hell in a hand basket, do you want to have to go forward to get the raft, possibly through a tangle of downed mast and shrouds, and somehow launch it from an exposed position? Could you even make your way forward if things are really bad? What if the reason for abandonment is a fire in the galley or engine room that is between you and the raft?

Center cockpit boats or those with a small afterdeck may find space aft, which alleviates these concerns. Some mount the flat-pack style vertically on the transom, but we think that too exposed.

Canisters also present some other considerations. Good ones are heavy, adding weight to the often already heavy raft, complicating launching. Can you slide it under the lifelines or do you need to go over them? One Switlik canister we tested weighed 28.6 lbs. The rest of the canisters we deemed tough enough to survive on deck weighed in around 20-24 lbs.

Even the best ones are not totally waterproof, to some degree leaving your rafts exposed to the elements, though vacuum packing the raft will fix that. However none of the rafts thus packed came with canisters that were robust enough for us to recommend.

Finally, we've all read of instances in which deck-mounted rafts were swept overboard. Properly securing the optional cradle and raft is not something to be taken lightly, often adding to initial cost. Plus there is the matter of security. You can padlock the raft down when ashore, but will you always remember to unlock it before shoving off?

Does a hydrostatic release make sense on a sailboat? In large part it depends where the raft is stored and what the chances are that it will release and not tangle in the lines and shrouds. We're not convinced of their value and don't consider them essential. Most require replacement every two years at a cost of around $150.

A valise presents its own compromises. While lighter and less bulky, it must be protected from the weather, meaning it'll need to be stowed either down below or in a locker in or around the cockpit. Down below means you have to go below to retrieve it—not the very best of arrangements. A cockpit locker can limit raft size, though some boats are now being built with this in mind. Winslow is the only manufacturer that offers “custom dimensional packing” to fit available space.

Our preferred location is in or around the cockpit. That's the best place, generally, from which to launch the raft and the safest place for survivors to congregate for boarding, with easiest access to stores below, if time allows.

In A Vacuum?
Vacuum packing, as used by Zodiac, West Marine, Crewsaver and Plastimo, can save money on initial services, which is appealing. It also does a better job of protecting the raft from the elements. Even many who don't currently vacuum pack their rafts confided to us that they expect to eventually move in that direction.

Next month, in the second installment of this series, we'll take a closer look at the inshore and coastal rafts evaluated.


Doug Ritter is a Practical Sailor contributing editor and the editor of the web site Equipped To Survive (www.equipped.org).

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