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Published on MadMariner.com (http://www.madmariner.com)
What to Expect Inside the Life Raft
By Steven Callahan

Welcome aboard. What do you mean you're scared? Of course you're scared. What are you complaining about? Sure you're crammed in here, your legs overlapping your mates' as you bask in your regulated, sumptuous four square feet of allotted space. Sure you feel like barfing because this raft stinks and feels like riding a jellyfish roller coaster. Sure you're cold. But hey, that's why it's called survival: to remain alive or in existence. That's it. Bare bones. Get used to it. Think where you'd be without any life raft or boat.

You thought being in a raft would be better than back in the boat? You thought that when you pulled the raft's rip chord maybe a brand new 40-foot cutter would pop out? Get real and be thankful skipper made you wait to bail out until you could "step up" to the raft; otherwise you wouldn't have gotten off that radio message or had the chance to gather the most gear.Steven CallahanSteven Callahan

Fortunately, conditions were not too horrendous when we did bail out, so it wasn't too hard to get the 100-pound, four-man raft overboard. It would have been nicer had the raft been lighter and smaller, but we'll be thankful that this raft is more heavily built. Since each case is unique, all safety equipment manufacturers try to satisfy the mutually-exclusive aims of making the gear simple, inexpensive, foolproof, light and small enough to slip into your pocket like a pack of cards while being as commodious as the Queen Mary – and providing unlimited features to address every conceivable kind of weather, situation and contingency. In reality, most good, heavily built and well-equipped rafts, especially those approved by SOLAS or the Coast Guard, must be rather large and bulky. Still, in storm conditions, I don't know if we would have gotten our heavy raft over in time.

We were also lucky that our boat wasn't rolled prior to abandoning ship, because our raft was cradled on deck, totally exposed to the sea. Luckily our raft cradle was heavily built and securely bolted through the deck, but because even quarter-inch bolts on some cradles have been sheared when boats have been rolled, all rafts and auxiliary safety gear would be most secure in a handy deck locker set flush into the hull or cockpit. Specialized lockers built into the boat would help protect the raft from long-term environmental damage too. Water intrusion into soft valises often have deteriorated metals due to electrolysis, and damaged fabrics.

Although water can also penetrate fiberglass canisters in heavy stainless racks, these offer much better protection than valises, which ideally should be stored in dry lockers. Some manufacturers also offer shrink-wrapped rafts, which also protect them from long-term damage during storage. Integral emergency-equipment lockers built into the mother craft, though, especially if positioned near the boat's perimeter and aft, such as in the lazarette with a door through the transom, could have allowed even a single crew member to deploy even a heavy raft and gear with a single yank of a lanyard.

'LET'S FACE THE MUSIC'

What if we couldn't get the raft off before the boat went down? A hydrostatic release would have let the raft go, but some crews have found their rafts prematurely deployed by the high water pressure created when their boats got rolled or overwhelmed by huge waves. A hydro-release or no hydro-release? That is just one of the plethora of judgment calls between compromises a crew must make when selecting gear on which their lives may become dependent.

Proper tethering is essential, of course. Many rafts have simply flown away in the wind when crews deployed them before making sure they were tied to strong points on the mother craft. We did that right, as well as making sure all our emergency equipment ditch kits – or "going away bags," as a friend calls them – were attached to long tethers, which allowed us to deploy the heavy, bulky raft first and then the bags, preventing all from getting separated from us, and lost.

So here we are, safe in the raft, at least for the moment. But it's not over yet, and nothing is as dangerous as false optimism and denial of danger. So let's face the music. We can still die of a lot of things: (a) fear, hypothermia (exposure) and physical injury, which can kill in minutes to hours, even in relatively warm waters, (b) dehydration, which can kill in days (about 10 average), and (c) hunger, which can kill in weeks (about 30 days).

The raft itself won't heal us, hydrate us or feed us. It's only the base requirement: a shelter and platform from which we can use our all-important survival tools. Right now it's cold. If our raft has a single-skin, non-inflated floor, I hope we salvaged air mattresses or cushions on which to sit. A raft with an inflated floor not only provides insulation but also protects us from bumping fish and sharks, which will be especially appreciated when we develop open-ulcers on the skin known as salt water sores, which can begin forming in a matter of days. A removable air pillow type floor allows water to drain away from us to help prevent sores and heat loss. If need be, we can lift it to repair it or the floor. A built-in inflated floor would prevent a leak into the interior if the bottom or top sheets of the floor are holed. In any case, there are no long-term survival voyages in cold waters, so I hope we have survival or immersion suits, or at least space blankets and chemical heat packs to keep our body temperatures up.

'IF THIS THING CAPSIZES'

The tent-like raft canopy helps keep us warm and protects us from the sun. This one is sealed to the raft tubes all around except at the entry opening, which unfortunately reduces ventilation in good weather. The single entry also impeded boarding compared to an open, roll-up type canopy, but some roll-ups are not secure enough to face hard weather, which would be horrible now that the weather is worse and we're flying around as if we were in a continuous auto accident. Whether the canopy is a roll-down type or fixed, it must be glued and taped to the inflation tubes all around or jets of water are going to force their way in here and rip the thing apart.

Thank God for our good entry port and other seam closures too: double sealed, zippered tight, and with sewn back-up ties. Little Velcro closures have been cursed by survivors since the Baileys' 119-day drift in 1972. A modest breeze can blow an entry closure open if secured only with Velcro. Even glued-on ties can get ripped off. If waves toss you or your gear out, or if they leave you awash and steal your heat, you can start listening for the end-of-your-life alarm. Speaking of which, we have tied all the gear in haven't we? The raft does have good handholds and secure attachment points, right? Okay, then, hang on.

Now don't freak out if this thing capsizes. We can right it, and with some practice we can right it without getting out. But we want to stay upright if we can. So many raft experts spend endless time arguing over what makes the most stable raft design – the huge Givens ballast bag, the Switlik doughnut-like torroidal system, or the common multiple ballast bags – but raft stability is only one important issue when considering a raft, and that stability depends on a lot of factors.

Steven CallahanSteven CallahanBeginning in 1978 NMI (National Maritime Institute, renamed British Maritime Technology Ltd. or BMT) in the United Kingdom began stability tests on life rafts in winds to hurricane force, including wind tunnel tests on model waves and model rafts in wind/wave tanks. These were followed by sea trials in conjunction with the Icelandic government in winds reaching Force 9, then more model tests, and finally more sea trials. Although each program had its limitations and none included any Givens-type ballast bags or Switlik's torroidal system, the tests included many manufactures, shapes, canopy styles and ballast systems. Results of all the tests reinforced one another. We can only interpolate results as they relate to rafts in general, and hope for further comparative testing.

'C'EST LA SURVIVE'

Both waves and wind cause life rafts to capsize. Water ballast pockets help resist capsize – the more, the merrier – but this is not the complete answer. Raft shape, wind under the floor, canopy shape, the loading of occupants, water ballast and sea anchors all influence stability.

Bows of square and rectangular rafts tend to dig in to waves as rafts are pushed downwind, particularly when the windward side is lifted by wind or breakers. Our raft is round and slides forward easier. Then again, when conditions moderate, our round raft will only allow one of us to stretch out flat in the center, whereas a rectangular raft would allow several of us to lie side by side. Oh, my, why does everything have to be a compromise? C'est la survive.

To help stabilize the raft, let's all huddle up here and hang onto the secure handholds on the windward side, lifting the bow more on the downwind side, and preventing the now-screaming wind from getting under the floor on the upwind side and flipping us. In addition, let's make sure the tubes are properly inflated. Some have argued that keeping tubes soft aids stability. Perhaps, but it also places huge loads on the material as the sea yanks the raft about. Some also promote keeping water in the raft, but this would stress our bodies more, and when the raft pitches, the water would slosh to the low side, reducing stability right where we would want to enhance it.

The wind is also trying to make our canopy into a spinnaker, so yank the canopy down on the windward side to prevent it from bellying up and creating overturning lift. It's also a good thing the sea anchor attachment is opposite the entry port so the entry faces downwind. Otherwise wind and breaking waves would attack the entry directly. If the wind breaks through an entryway facing upwind, it will turn the canopy into an overturning sail. If we let breaking waves crash through our entryway, they would fill our cave, steal our heat, steal our gear and quite probably even rip the canopy right off.

'MOST ARE DOGS'

Right now we enjoy the low, rounded profile of our canopy support tube, which reduces our windage. In calmer seas we'd prefer higher, squarer canopy support tubes, which would allow more of us to sit up. The Switlik coastal canopy offers the greatest flexibility in design. Its ends are secured to the tubes to provide reasonable security in heavy seas, but in lighter going the midship canopy can be completely removed and the ends rolled down in various combinations to provide ventilation, work space, or, with only one end erected, sail area.

NMI and the Icelandic government found that the best normal water-ballast pockets were triangular in section and usually weighted to promote quick filling. Many ballast pockets still failed and, "Of the six rafts put into the water, only those on which sea anchors remained operational did not capsize," the study said. The last test showed, "the sea anchor was a powerful stabilizing force and could prevent the life raft from capsizing even when the ballast pockets were destroyed."

Not just any sea anchor, however. Most are dogs. The improved sea anchor is a tapered sleeve, at least twice as long as the mouth is wide and the tail a third the mouth's diameter. The mouth should be stiff and open to promote quick filling. If it's made of porous mesh it doesn't need a swivel, but a swivel never hurts. Flat panels of cloth forming parachute-type sea anchors, and cones, will spin, so they require swivels. Even so, they can foul themselves with their bridles if they tumble forward in breaking waves.Steven CallahanSteven Callahan

NMI found that mesh or laces sewn around the sea anchor bridle prevented sea anchors from fouling themselves. A new option is the series drogue, which is a string of smaller cones that reduce shock loads by evening out the sea anchor's pull over numerous waves aft. In any case, our sea-anchor rode, swivels, and attachment point on the raft had better be tough because the snatch loads in even moderate conditions can be eight or nine times the anchor's steady pull.

BALLAST BAGS

Numerous raft styles with varying water-ballast schemes have survived upright in blows exceeding 80 knot winds and 30-foot waves. One heavily-ballasted Givens raft resisted wind gusts to 170 knots and 35-foot seas when survivors were forced under water numerous times and the tubes began to separate. Who knows if other rafts could survive such conditions at all, but if force equals mass times acceleration (or deceleration), then the mass of boat or raft must increase the loads it experiences when at sea. So it is no surprise that the most heavily-ballasted rafts must be the most heavily built.

This concept was supported by tests. "Over-large ballast pockets can place a great strain on the raft structure leading to a need to strengthen it, with a consequent increase in weight and cost. Also, an already uncomfortable motion is made much worse on a raft carrying too much ballast," According to Testing of Liferafts by E.J. Foreman of BMT. Proponents of heavily-ballasted rafts continue to debate this view. I only know that riding a life raft of any kind is hellish in a gale, all have suffered failures and being capsized is only one of numerous worries for survivors, not in itself necessarily critical. The records for distance and time afloat go to much more lightly ballasted rafts. All types, including the Givens, have been knocked down to 90 degrees in waves of only 15-feet. As on the mother craft, sailors should always plan to have the sea turn their life upside down at some point.

A REAL DRAG

It is moderating? Most of a long survival voyage is spent drifting slowly in moderate weather, and boats more often come to grief for reasons other than horrendous weather. In any case, our EPIRB hasn't brought help, so why not get the hell out of here?

Now our big ballast bags are a real drag and we wish the canopy would open up more. Cut the ballast off? Why have it to begin with, then? And what about the next blow? Tie the bags up? Okay, best we can do.

It certainly would be nice to have a completely different kind of raft now, what the French call a "Dynamic" raft, meaning the thing sails. When I lost my boat in 1982, had I been able to beam reach, I could have shortened my drift from 1,800 miles to 450; had I been able to sail even dead downwind but increase speed to a moderate 2.5 knots, I would have been afloat 25 days rather than 76; had I been able to do both I would have sailed to safety in a mere six or seven days.

Some lucky survivors escape with a dinghy or inflatable sport boat as well as a life raft. With two boats, survivors can fan out to work or rest more efficiently, and set sails to make real headway. A dinghy should be unsinkable or have watertight compartments, maybe even have its floatation augmented by fenders or inflatable collar secured to the outside. It should also carry additional emergency gear, tarps, sea anchor and more.

Personally, I wish for a life raft shaped like a sport boat, but wider, with a high bow to resist pitchpoling, a retractable ballast system, and a reasonable rig or kite sails for propulsion. But most ocean disasters involve aircraft, commercial shipping, and oil rigs, not voyaging yachts, so most bureaucracies promote stability of position to assist Search and Rescue. If you want a good sailing lifeboat that can be carried on a small yacht, you'll have to create it.

'IMMEDIATELY DISASTROUS'

Why is this bottom tube soft? Leaking already? I hope we have some good repair clamps. Those glue patches that say "Material should be dry prior to application" are as cruel a joke as the fishing kit that consists of a 50-foot piece of string and a hook. Why didn't we look closer at the equipment that came with the raft? Good thing we have our own gear. Also good thing that most life rafts have two separate inflation chambers. Still, with a bottom chamber collapsed, water forces distort the shape so that the raft will sink surprisingly low in the water. The entire floor becomes like rubber quick sand. Waves easily wash across the few inches of upper tube remaining above water. If we can't fix it, we'll suffer more sores and hypothermia, and living becomes nearly impossible over even the modest term. Can you blow up the raft by mouth? Most good valves require a pump, though a few can be operated by mouth. What about the pump itself? Is it easy to use? Have we got a spare in case it breaks or is lost?

In most single-inflation-chamber rafts, a hole is immediately disastrous. Some rafts have inner safety tubes, however. Switlik's single-tube coastal raft is divided by inner socks that are forced by air pressure from the secure side into the damaged half of the tube as air escapes. The Butlers lived happily in this kind of raft for 66 days in 1989. Well, maybe not happily. But in most single-tube rafts, or sport boats, if you get a leak you've got a problem that can ruin your whole life. Your only hope then rests upon effective and very easy-to-deploy raft-patching clamps or similar repairs.

Steven CallahanSteven CallahanIt finally rains. We're smart enough to carry a reverse osmosis pump, but rain will allow us to drink more, build our stock and wash to heal our sores. Canopy gutter systems are a bonus. Some canopies still break down in time, though, making water undrinkable. You can't be sure when they're new how they will wear over time, so we carry some plastic sheets or space blankets to catch water and containers to store it, don't we?

Oh goody. Here comes our ride. We have been lucky to have been spotted for rescue in less than 24 hours. Still, it's night. I'm glad we a good choice of quality flares, from handheld spot-locator flares to parachutes for attracting rescuers to the general area. Just as important, or more so, we can communicate using our hand-held VHF, and a lot of nice reflective strips on the outside to will greatly help the ship's spotlight to find us in the waves.

It goes without saying that we hope our raft is well made, but construction is beyond our scope here. Before you find yourself embarking on your life raft journey, talk to raft service people who see the best and worst, keep up with materials and construction technology, and see what makes have to be fixed the most frequently.

Your raft can really only help keep you warm and secure in cold and rugged seas. The best may even give you a third chance if it is damaged. I hope future rafts or secondary craft will promote mobility as well. The rest of survival – the food, the water, first aid, navigation and learning to live with the sea – is up to you and your equipment. A good raft will put you in the mood, however. It'll reassure you, shut down the panic, make your voyage fun! Well, maybe not fun, but it would be a whole lot less fun without it.


Steven Callahan is the author of “Adrift: Seventy-Six Days Lost at Sea,” and eight other books on survival and seamanship. He has logged more than 70,000 offshore miles and completed several ocean crossings. A modified version of his article originally appeared in Ocean Navigator magazine.


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