At Holloman Air Force Base in New Mexico on December 10, 1954, the Sonic Wind No. 1 rocket sled let loose 40,000 pounds of thrust and propelled United States Air Force flight surgeon Col. John Stapp more than 3,000 feet in a few seconds. He came to a stop just as fast and experienced a force equivalent to approximately four tons (46.2 g). Although bruised and badly shaken, Colonel Stapp survived without permanent injury and walked away with the world land speed record, 632 miles per hour. (That is faster than a 45 caliber bullet shot from a pistol!)

The benefits of Stapp’s research are evident every time a driver pulls on a seatbelt or a jet pilot safely ejects from a damaged aircraft.

Shortly afterward, Stapp commented on the experience and what it felt like: “I felt a sensation in the eyes…somewhat like the extraction of a molar without anesthetic.” That did not deter Stapp from wanting to go even faster. He planned to add a few more solid fuel rocket motors to the back of the sled and break the 1,000 mph threshold, but his Air Force superiors said no; They didn’t believe he would survive.

Right 1/2 Front view as Lt. Col. John Paul Stapp is strapped into "Sonic Wind No. 1", one of the rocket sleds used by Lt. Col. Stapp for physiological testing. Note the motion picture cameras at the forward edge of the sled platform to photograph Lt. Col. Stapp during the tests.

What prompted Stapp to take such extreme personal risks? Was he eccentric? Out of his mind? Some observers may have thought so. But his upbringing did not give any hint of the type of daredevil behavior that would define his later career. Born to missionary parents in 1910 and the eldest of four boys, Stapp earned degrees in zoology, biophysics, and medicine before embarking on a military career, first in the Army Air Forces during World War II, and then in the USAF.

Stapp sought to advance science in response to new technological advances in high-speed flight. Jet aircraft subjected pilots to extreme forces at high altitudes, and little was known about the effects of prolonged exposure on human physiology. Few safety guidelines and standards existed as aircraft performance and speed rapidly advanced. Stapp wanted to understand human responses to acceleration, deceleration, and windblast to improve pilot safety, especially in cases of ejection from disabled aircraft. He pioneered—and put a human face to—the new field of aeromedicine.

Composite showing Col. Stapp during rocket sled test at Holloman AFB, NM. Test to study effects of bailout at high altitude and supersonic speeds. Photos 1-3 taken during acceleration phase: force = 12 G; 4-6 during deceleration: force = 22 G. Dated June 1954.

Stapp’s research in the Air Force also spilled over into automobile safety. His work led to the safety standards and technologies we take for granted today. The benefits of Stapp’s research are evident every time a driver pulls on a seatbelt or a jet pilot safely ejects from a damaged aircraft.

This is the Sonic Wind 1 rocket sled, which was powered by nine solid fuel rockets with 40,000 pounds total thrust for five seconds.

The Sonic Wind No. 1 rocket sled that Stapp rode into the history books in 1954 is currently undergoing a major restoration in the Museum’s Mary Baker Engen Restoration Hangar at the Steven F. Udvar-Hazy Center in Chantilly, Virginia. Previously, it sat on display for four decades at the New Mexico Museum of Space History, next to Holloman Air Force Base. Once restored, the sled will go on display in a new gallery called Nation of Speed at our National Mall Building.

For more stories, updates, and sneak peeks at what’s changing at the Smithsonian’s National Air and Space Museum, check out airandspace.si.edu/reimagine.