Emily Anthes is a science journalist and the author of “Frankenstein’s Cat: Cuddling Up to Biotech’s Brave New Beasts.”

Sonic Wind
The Story of John Paul Stapp and How a Renegade Doctor Became the Fastest Man on Earth

By Craig Ryan

411 pp. $27.95

Shortly after noon on Dec. 10, 1954, the sun finally broke through the clouds at Holloman Air Force Base in New Mexico, and the countdown began. Two minutes later, nine rockets fired, propelling John Paul Stapp — and the 2,000-lb. sled he was strapped into — down a 3,500-foot track. Within five seconds, he was traveling at 639 miles per hour. It was a new land-speed record, making Stapp, a lieutenant colonel in the U.S. Air Force, the fastest man on Earth.

At least temporarily. A second and a half later, the sled slammed to a stop. “In a microsecond, all momentum was reversed,” Craig Ryan writes in “Sonic Wind,” his compelling and compulsively readable new biography of Stapp. “His organs surged forward and Stapp’s visual field went from black to yellow in a stroboscopic flash. . . . The last residue of breath was crushed from Stapp’s lungs and a terrible needle-like pain hit him in his gut. Then the pain all seemed to shoot into his face as the sheer force attempted to gouge the eyeballs from their sockets.” Remarkably, he “emerged not only alive, but fully conscious.”

‘Sonic Wind: The Story of John Paul Stapp and How a Renegade Doctor Became the Fastest Man on Earth’ by Craig Ryan ( Liveright)

Pain aside, it was a crowning moment for Stapp, a doctor and researcher who spent his career acting as a real-life crash-test dummy, collecting data that ultimately helped the military to design safer planes and the automobile industry to build safer cars. “Sonic Wind” is a curious but charming tale, the story of a man who courted danger — and death — in the ultimate pursuit of safety.

Stapp was born in Brazil in 1910, the first child of American missionaries. He returned to the United States for high school and college and was considering a writing career when a pair of tragedies stuck. During his Christmas vacation, his 2-year-old cousin sustained horrific, ultimately fatal burns in a freak accident. When Stapp returned to college in January, he learned that his girlfriend had been killed in a car accident.

Stapp’s interest in literature and music “suddenly seemed frivolous,” Ryan writes, and the 18-year-old decided to pursue medicine instead. By October 1940, he had earned a PhD in biophysics and was on his way to his medical degree when his number was selected in the new military draft lottery. He joined the Army Medical Corps, attended the School of Aviation Medicine and eventually landed at the Aero Medical Laboratory at Wright Field in Dayton, Ohio. At Wright, Stapp personally tested a new oxygen-delivery system in a nonpressurized plane flying at high altitude and became a regular rider of the human centrifuge, “a high-speed industrial merry-go-round” designed to help researchers assess the effects of extreme acceleration on the human body. “Stapp had come to understand that if he wanted to study a phenomenon, there was nothing better than experiencing it himself,” Ryan explains.

After impressing his superiors, Stapp was given command of a new project at Muroc Army Air Base in the Mojave Desert. There, working in a primitive lab with little financial or logistical support, he oversaw the construction of a rocket-powered sled capable of hurtling down a 2,000-foot track more at than 200 mph. He had been charged with evaluating protective restraints that might safeguard pilots in a crash, but he had a grander vision: testing the limits of the human body. At the time, the military believed that, in the event of a plane crash, humans could not survive forces that exceeded 18 times the force of gravity, or 18 g’s. Stapp suspected that the body was far more resilient than that. Of course, Ryan writes, “the only way to test his theory was to simulate an airplane crash in a controlled environment: a speeding vehicle, moving horizontally, that could be slammed to a dead stop.”

Dummies, chimps and pigs all went zooming down the track, but Stapp also took dozens of rides himself — both at Muroc and then later, on the faster, more powerful rocket sled at Holloman. Along the way, he set multiple land-speed records and ultimately withstood forces of more than 46 g’s. He took a beating — he tore cartilage between his ribs, broke both wrists, bruised his collarbone, fractured his coccyx, sustained several likely concussions and nearly blinded himself — but he survived.

By merely surviving, Ryan explains, “Stapp had rewritten much of the School of Aviation Medicine’s textbook on human tolerance and had thrown a gauntlet at the feet of the nation’s aircraft industry.” American planes had performed poorly during World War II, and pilot fatalities were high. But the military had resisted calls for stronger cockpits, seats and restraint systems, arguing that there was no point in designing planes to withstand g forces that humans could not survive. Stapp proved that, with proper protection, humans could tolerate unthinkably strong forces, prompting the military to revise its strength standards and redesign its seats.

Stapp’s remarkable deceleration experiments form the heart of “Sonic Wind,” but Ryan also chronicles the doctor’s countless other contributions. Stapp performed impact experiments for NASA and oversaw several high-altitude balloon flight projects, one of which led to the development of a parachute that allowed flight crews to survive falls from the stratosphere. He also took an intense interest in automobile safety, conducting some of the first tests of airbags, testifying at congressional car-safety hearings and proselytizing endlessly for seat belts, which were not yet standard in American cars.

“It’s been suggested that Stapp was indirectly responsible for saving more lives than anyone in history,” Ryan writes. “They were all the ghosts that never happened.”

“Sonic Wind” is an engrossing read, and Ryan brings his unlikely hero to life, deftly describing Stapp’s missionary zeal — inherited, presumably, from his parents — for safety. Stapp was driven, stubborn and occasionally downright defiant when he believed that officials were standing in the way of research that could save lives. He never relented, and when he died, he did what he had spent nearly all of his life doing: He donated his body to science.