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An Unsinkable Spinoff
Apollo astronauts and a Navy frogman in biological isolation garments await pickup from a helicopter. Apollo astronauts and a Navy frogman in biological isolation garments await pickup from a helicopter.
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Givens Buoy Life Raft Available in a variety of sizes, the Givens Buoy Life Raft can be used on small sailboats or large fishing vessels. It fully self-inflates in under 12 seconds.
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Apollo-Era Life Rafts Save Hundreds of Lives

The Apollo astronauts may have safely traveled half a million miles to the moon and back, gone through reentry, and landed in the ocean, but they weren’t out of danger yet. Having left their capsule and released a marker dye into the water, the crew climbed aboard a life raft to await rescue. But unfortunately, the very helicopter sent to retrieve them posed one final threat, as its powerful rotor downdraft was enough to flip a typical flat-bottomed life raft.

To keep the astronauts secure in the very last moments of the mission, NASA set to work developing a life raft that could withstand choppy conditions created by strong winds. The Agency’s efforts would soon after benefit a small manufacturer and go on save the lives of those in distress at sea.

Safe Harbor for Astronauts

Engineers at NASA’s Johnson Space Center designed and patented a hydrodynamically stabilized ballast system that would prevent a life raft from tipping in rough conditions. Using ocean water to weight the raft proved an effective defense against the tumult of wind and waves. And because the predeployed raft didn’t need to include its own weighted ballast, the design reduced the weight and space required by the raft—always a desirable trait for a space mission, where every ounce of weight and inch of space matters.

At the same time, inventor Jim Givens was at work on his own idea, designing a canopied raft with a hemispheric ballast chamber. Having patented his own system, Givens saw the value in NASA’s work and obtained an exclusive license for the Agency’s innovation. Givens Marine Survival Co. Inc., of Tiverton, Rhode Island, now manufactures and markets the rescue rafts—under the name Givens Buoy Life Raft—in a variety of sizes and models for everything from sailboats to larger ocean-going vessels.

The Givens raft, like the NASA design, relies on a heavy, water-filled ballast. A flapper valve allows hundreds of gallons to enter the hemispheric chamber. This water provides the weight that keeps the center of gravity constant, much like the thousands of pounds of lead keel used to stabilize sailboats. Even if the raft is submerged by a large wave, it is designed to somersault and right itself: The momentum of the water in the ballast chamber levels the whole vessel upright again.

A Sea-Worthy Technology

Extensive Coast Guard testing demonstrated that the raft could not be capsized by rough seas or strong winds. The testing included simulated rescue hoists from Coast Guard rescue helicopters, simulated hurricane force winds from a C-130 aircraft slipstream, drift tests, weight distribution and stability tests, and “at-sea” testing. In each instance, the Givens life raft withstood the most brutal of punishments.

Nevertheless, testing—no matter how well-designed—can never fully account for what might happen at sea. It is the testimonials from people whose lives have been saved by these rafts that really speak to their ruggedness—like the story of four sailors caught in the middle of the second worst storm ever recorded on the Atlantic. With winds gusting to 195 knots per hour, their 30-ton ketch capsized, and the crew sought refuge in their Givens Buoy Life Raft. The four men rode 35-foot waves over the next 42 hours before being rescued, with the raft at times being submerged under several feet of water, flipping, and then righting itself.

To date, Givens has sold several thousand of the ballasted inflatable life rafts, and this space-age technology is credited with saving the lives of more than 450 sailors. Thanks to technology transfers from NASA to the public, what began as an effort to keep astronauts secure in the final moments of their journey now keeps thousands of people safe at sea—in any conditions.

To learn more about this NASA spinoff, read the original article from Spinoff 2009.