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Whenever Felix Baumgartner makes his jump from roughly 23 miles above Roswell, N.M., the only thing protecting the Austrian sky diver as he hurtles through the Earth’s atmosphere near the speed of sound will be a high-tech, pressurized suit designed by a Worcester company.
Baumgartner’s leap, postponed Tuesday because of high winds, is meant to test advances in the technology used to make spacesuits, and to collect data that will help companies like the David Clark Co. of Worcester make further improvements to such gear. The firm has specialized in outfitting high-altitude aviators and astronauts for 71 years.
Backed by the energy-drink maker Red Bull, Baumgartner’s jump has gained worldwide attention through social media. When he makes the leap from a record 120,000 feet — perhaps later this week — Baumgartner will have just four layers of specially made materials, oxygen, and pressurized air between him and the unforgiving climate that could turn his blood and other bodily liquids to gas above 62,000 feet.
Fully-suited, he’ll be a 260-pound bullet speeding to the ground during a 5 ½ minute, 690-mile-an-hour free fall that will end when his parachute deploys at 5,000 feet.
“One of the things Felix is hoping to do is break the speed of sound,” said Daniel Barry, vice president and director of research and development at the David Clark Co. “Whether he does that or not is secondary to the main objective, which is to sustain life.”
To ensure that Baumgartner, 43, survives the trip, specialists at the David Clark Co. used their expertise to custom build a suit for the sky diver using selectively permeable materials, like Gor-Tex, that can hold air but let moisture through, and Nomex, which is heat and flame resistant.
The suit has four layers: an innermost comfort liner, a gas membrane that retains air pressure, a restraint layer that gives the suit its shape, and a fire retardant exterior cover that provides protection and insulation from extreme heat and cold.
Meanwhile, a “smart valve” automatically adjusts as Baumgartner falls so that his suit maintains a pressure equivalent to that found at 35,000 feet.
“It’s like getting into a balloon, but it’s an anthropomorphically shaped balloon,” Barry said. “It’s just like when you fly on JetBlue. They don’t give you a suit [but] they put you in a tube and the tube is pressurized.”
The David Clark Co. is considered a pioneer in the field, having designed protective equipment for air and space crews since 1941. The company outfitted the rocket plane test pilots who broke the sound barrier, and created the suit used in the first US spacewalk.
While Baumgartner’s suit takes much of its design from spacesuits, it is built to allow more flexibility at the joints — like fingers, elbows, and wrists — than an astronaut’s typical gear, which is made for sitting and is often hard to maneuver.
Baumgartner needs the wider range of motion to execute the steps he needs to exit from a pressurized capsule carried to 120,000 feet on a thin-skinned helium balloon. If all goes as planned, he’ll bunny-hop from the capsule’s platform feet first, then — at about 25 seconds into his dive — rotate into a head-down position that will allow him to gain speed.
Baumgartner has been planning this jump for years, and training for it since 2009 with the help of Joseph Kittinger, a retired Air Force colonel who made a record 102,800-foot jump in 1960 — also wearing a suit from the David Clark Co.
When Baumgartner finally takes his leap, the whole thing will take about 15 to 20 minutes — with a supersonic free fall in between.
“Then he’s just a speeding bullet,” said Derrick Lerum, a spokesman for Red Bull Stratos, the team coordinating Baumgartner’s dive. “That’s when he breaks the sound barrier.”