The Land Shark Instant Survival Shelter is a multipurpose survival bag that’s affordable, lightweight, compact, and reversible: international orange on one side and digital camouflage on the other. The orange is highly visible, critical for rescue at land or sea, and the camouflage side, meant primarily for military use, might come in handy if you want to take refuge ashore without attracting unneeded attention. The outer layers of the laminated material conceal and protect a layer of aluminized film that reflects heat to provide warmth without the bulk of insulation. The bag weighs 22 oz and is 6″×8″×1″ when stowed in its zippered pouch and 38″×80″ when unfolded. It is designed to fit any person up to 6′3″ and we found that two people could fit inside the bag, an asset for rewarming someone with hypothermia. The waterproof, ripstop material is much more durable than a pocket-sized aluminized Mylar blanket, and bag provides better protection from the elements and warmth retention than a space blanket. It comes with a plastic clip and a whistle attached.
I tried the bag outside with the air temperature at 45 degrees Fahrenheit and without sunlight. I was barefoot and wearing shorts and a T-shirt. Getting into the bag is as easy as putting on a pair of pants: It takes about 20 seconds. After getting in, I tucked my head inside and pulled the drawstring tight to create a dead air space. Within 10 minutes the temperature inside climbed to 63.5 degrees. For a second trial, to simulate a man-overboard rescue scenario, I hosed myself down with 41-degree water, and slipped into the bag. I felt an even more distinct sense of warming up than I had when I was dry. As the bag warmed up, my reading glasses even fogged up. After 10 minutes the internal temperature stabilized at 57.2 degrees. Creating the dead air space was critical to warmth, and the great advantage of the bag over a blanket. Keeping the opening small and tight around my face kept me warm. With even a small gap I could feel cold outside air getting in. I minimized conductive heat loss by sitting on a boat cushion or dry forest duff on land. If I rested on heat-draining surfaces like concrete, I could feel the cold.
I tried using the Land Shark bag in the water, a use indicated on the manufacturer’s website. It is feasible to get into the bag in the water, and it may, as the manufacturer suggests, extend survival time, but it is not a substitute for the buoyancy provided by a PFD or the functional thermal protection of a wet suit or dry suit.
The bag’s aluminized layer, by reflecting radiated heat, also offers “tactical stealth” and can help evade detection by thermal imaging equipment. While that’s useful in a military application, the thermal cloaking must be kept in mind in a survival situation. We conducted a mock search-and-rescue trial with an infrared camera. A person inside the bag was virtually invisible. An arm or a head left uncovered by the bag provided a clear image on the camera monitor. If you are in a survival situation and visibility is obscured you’ll want to get at least partially uncovered if you believe rescuers are nearby. They may be using infrared imaging to find you.
The aluminized film also makes a strong radar reflection—good news for small wooden boats. When we set a 40′ yawl’s radar at a ¼-mile range and 1,000′ away, the outstretched bag, suspended 6′ above the water level, was a smaller target than the 30′ to 50′ sailing and power boats moored nearby but just as easily discernible.
The Land Shark bag is a compact and versatile piece of equipment for a make-do weather protection for someone who neglected to bring rain wear, an unexpected bivouac ashore, an impromptu radar reflector if caught up in reduced visibility, or a means of warming someone after a man-overboard rescue. It’s worth having aboard.
Capt. David Bill is a Sea Survival Instructor at Tabor Academy in Marion, Massachusetts, and writes about his adventures on his blog, Boats and Life.
The LandShark Survival Bag sells for $65 and is available online from Corporate Air Parts.
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