After Vietnam, David Epstein explains (in Inside the Box), the Army moved from Nylon flak vests to Kevlar, then added rifle-proof ceramic plates, and then added extra protection against “frag” for the neck, groin, shoulders, etc.:
When a vehicle rolled over, or caught fire, or went underwater, soldiers were unable to move quickly enough to escape.
In 2007, a redesign of body armor that was meant to improve mobility was only able to save a single pound. Instead of reducing weight, the new design featured a quick release tab that the wearer could pull to cause the armor to drop off. It was helpful in an emergency, but didn’t solve the overall mobility problem.
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Shortly before the GAO report was published, the secretary of defense ordered the military to open all combat jobs to women, which made the issue of bulky armor even more acute. As women joined the close-combat force, some were outweighed by their equipment. Aside from the weight, it didn’t fit well. On average, of course, women are smaller than men, and shaped differently in ways that are both obvious and nonobvious—proportional to their height, for example, they tend to have shorter limbs.
Pierre-Zamora is thirty-eight, and told me that back when she got her first vest in basic training, the bottom of the ceramic plates were so low that they’d jab into her thighs when she bent down, making it difficult to squat or bend over. And the vest was so broad that she had to yank it to one side in order to shoulder a rifle.
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“I’m a short, heavy guy,” Miller said. “My torso length says I should wear a small vest, but my gut says I should wear a medium.”
Miller’s comment is reminiscent of a story recounted by scientist Todd Rose in his book The End of Average. Rose described how, at the dawn of jet-powered aviation in the 1940s, US Air Force pilots were suffering an enormous number of training accidents. Seventeen pilots crashed in a single day. The carnage was ascribed to pilot error, until a young lieutenant prompted a closer look at the jet cockpits. They had been designed based on the average measurements of hundreds of pilots. But even taking just a few basic body measurements—like height, sleeve length, thigh circumference—the lieutenant found that essentially no individual was near the average on all of them. In designing a cockpit to fit the average pilot, plane manufacturers had designed a cockpit that fit no one. The solution was adjustable cockpits. User error, it turned out, was actually designer error.
The Army learned the same lesson with protective gear. Not long after the GAO report (and the stuck infantryman), the Army started rolling out the body armor version of an adjustable cockpit: the modular scalable vest, or MSV. With interchangeable parts, it allowed soldiers to remove weight if they didn’t absolutely need it. It also gave the flexibility to match a size small outer vest with the belly protection of a size medium, which solved Miller’s torso-length / gut conundrum.
The MSV was sleeker and lighter than its predecessor. Instead of eleven standard sizes, the new armor came in eight, three of which were specifically based on measurements of female soldiers: extra-small short (extra-narrow vest with short ceramic plates); small-short; and small-long (narrow vest with long plates). With those new sizes, something unexpected happened.
“Women are about two percent of the close-combat force,” Miller told me. “But what we found is about twenty percent of that force is best fit in equipment we built for these women.” So many men were better off with the vests designed for women that the Army made sure to brand them carefully. “I’ve had to explain to Congress several times that we built the vest for women,” Miller said, “but we call it unisex because we want men to wear it.”
In particular, physically fit men in the close-combat force often switched from a medium in the old vests to small-long in the new ones—a narrower vest but a protective plate long enough that it still covered their vital organs. A lot of men had also been yanking aside their vest to shoulder a rifle, but now they didn’t have to. Additionally, a notch behind the neck was built into the new gear to make space for women’s hair buns. As it turned out, everybody liked to be able to lift their head while prone, so it became a standard feature. And a new, more meticulous sizing process that benefited women benefited everyone.
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As Miller told me: “Looking at some more extreme users, or niche users, and using them to make something better for everybody, that’s kind of what we did here.”
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The challenges faced by “extreme users,” as Miller referred to them—whether they be people who are particularly small or big, old or young, or with disabilities—frequently represent more extreme versions of the challenges that many other users face. Universal design, then, is just good design, and centering user constraints is a way to focus on the most important challenges.
Todd Rose gave a Google talk on his book years ago: