1. Franz Reichelt
On February 4, 1912, Austrian-born French tailor Franz Reichelt climbed to the top of the Eiffel Tower in a wingsuit of his own design. The tailor had told French authorities he planned to test the suit using dummies, but upon his arrival at the tower, he announced that he would make the jump himself. His friends tried to dissuade him, citing wind speed and other factors—including previously unsuccessful attempts with dummies—but Reichelt was not moved. He would not use a safety rope or any other precautions. “I want to try the experiment myself and without trickery, as I intend to prove the worth of my invention,” he told journalists.
Newspapers described the suit as “only a little more voluminous than ordinary clothing” that, when extended, resembled "a sort of cloak fitted with a vast hood of silk." To release the parachute, which had a surface area of 320 square feet and a height of 16 feet, Reichelt merely had to extend his arms out so his body was in a cross position.
By 8:22 a.m., Reichelt was at the top of the Eiffel Tower. He adjusted the suit, and, facing the Seine, tested the wind direction by tossing a scrap of paper off the edge. Then, he placed one foot on the guardrail, and—observed by 30 journalists, two cinematographers (one up top, and one of the ground), and crowds gathered below—jumped (You can watch his fall here, but take note: it may be unsettling for some people.)
The parachute folded around Reichelt almost immediately; he plummeted for a few seconds before hitting the ground 187 feet below, leaving a crater 5.9 inches deep. His injuries were gruesome—in its April 1912 issue, Popular Mechanics reported that "his body was a shapeless mass when the police picked it up"—and the tailor was dead by the time onlookers reached him. An autopsy later determined he died of a heart attack during his fall.
2. Thomas Midgley, Jr.
Thomas Midgley, Jr., an American engineer and chemist, developed additives for gasoline as well as CFCs, and was awarded over 100 patents in his lifetime. When he contracted polio at age 51, he applied that inventor’s spirit to his impairment, creating a system of strings and pulleys that would make it easier for others to lift him out of bed. In 1944, when he was 55, Midgley became entangled in the ropes and was strangled by them.
3. Henry Smolinski
Engineer Henry Smolinski wanted to create a commercially viable flying car, so he quit his job at Northrop and started Advanced Vehicle Engineers. In 1973, the company built two prototype vehicles, called AVE Mizars, by fusing the rear end of a Cessna Skymaster airplane—which could be attached and detached from the car—with a Ford Pinto. The chimera vehicles were due to go into production in 1974, but on September 11, 1973, Smolinski and his friend and business partner Harold Blake were killed when the wing strut detached from the vehicle during a test flight. Bad welds were responsible for the crash.
4. Karel Soucek
In 1984, Czechoslovakian-born stuntman Karel Soucek went over Niagara Falls in a custom-built, shock-absorbent barrel that was 9 feet long and 5 feet in diameter. He emerged, alive but bleeding, at the bottom, and decided to build a museum dedicated to his stunting equipment in Niagara Falls, Ontario. To finance the project, he convinced a company to sponsor another crazy stunt: Dropping the barrel, with Soucek inside, 180 feet from the top of the Houston Astrodome into a tank of water as part of a Thrill Show and Destruction Derby to be held on January 20, 1985.
Even daredevil Evel Knievel tried to talk Soucek out of the stunt, calling it “the most dangerous I’ve ever seen,” but the stuntman proceeded anyway. When the barrel was released, it began to spin dangerously, hitting the rim of the water tank instead of landing in the center. The 37-year-old’s chest and abdomen were crushed and his skull was fractured; he died at a hospital while the show was still going on.
5. William Nelson
On October 3, 1903, 24-year-old General Electric employee William Nelson took the new motorized bicycle he had invented out for a test spin. He fell off the bike on a hill and died instantly. According to the New York Times, “Nelson was regarded as an inventor of much promise.”
6. Valerian Ivanovich Abakovsky
Valerian Abakovsky was just 25 when he invented the Aerowagon, a high-speed railcar equipped with an aircraft engine and propeller traction, which was designed to take Soviet officials to and from Moscow. On July 24, 1921, a group of Communists—including Abakovsky, revolutionary Fyodor Sergeyev, and four others—took the Aerocar out for a test run. The vehicle successfully made the trip from Moscow to Tula, but on the way back, it derailed at high speed, killing six of the 22 people on board.