How do some people survive falls from great heights?

The story of a 13-year-old boy from North Dakota who survived a nearly 100-foot fall from the Grand Canyon's North Rim startled the world in summer 2023. His case, however, is not unique. Over the years, several people have made headlines for their odds-defying survival after falls. At the extreme end of the scale — and perhaps the most famous example — is the remarkable case of Vesna Vulović, a flight attendant who survived a 33,000-foot fall from a plane without a parachute in the 1970s.

So how is it possible to survive falls from such staggering heights?

One of the first factors to consider, of course, is exactly how high you are when you fall. "Overall, we say that if somebody falls from 48 feet [15 meters], which is about four stories, 50% of them will die," Dr. Demetrios Demetriades, a professor of surgery at the Kerk School of Medicine of the University of Southern California, told Live Science. "If someone falls more than 60 feet [18 m], this is usually lethal, and it is extremely unlikely, or a miracle, if a patient falls from higher than 80 feet [24 m] and survives."

But another big factor is whether a person was in free fall, which boils down to a fundamental principle in physics. "Any object that falls from a great height reaches something called terminal velocity, which is why parachutes work," Anette Hosoi, a professor of mechanical engineering at MIT, told Live Science.

When you fall, the main force that acts first on you is gravity, she said. However, as you speed up, the drag from the air increasingly resists your downward motion. At some point, this air resistance exactly balances out the pull of gravity, so you keep falling at the same speed.

"If you have a parachute where you have a big area that's resisting all this air flow, your terminal velocity is like 10 miles an hour [16 km/h], which is fine," she explained. "If you're a person without a parachute, it may be — depending on if you're vertical or horizontal — about 150 miles an hour [241 km/h], which is obviously a problem."

How you land is crucial to your likelihood of survival.

"It's all about how fast you're going and how quickly you stop," Hosoi said. If you land on a slope, for example, you would gradually burn off all the energy of the fall as you slide down, which is better than stopping abruptly, she said. The body part you land on also influences your fate.

"The worst way to fall is on your head," Demetriades said. "Probably if you fall on your feet, you might have better chances of survival, but again, it is a multifactorial thing."

According to Demetriades, age also influences a fall victim's chances of survival. Often, falling cases in the news involve children, like that of the North Dakota boy or another recent case of a 6-year-old who survived a 40-foot [12 m] fall from a zip line in Mexico

This may not necessarily be a coincidence. "If you compare falls from the same height, victims younger than 15 years old versus those older than 65 years old, the death rate in the older group is about five times higher," Demetriades said.

"Children generally recover much better," he said. "They have a lot of physiological reserves, and secondly, their bodies, especially their bones, are designed to withstand much bigger stresses."

For Hosoi, the explanation comes back to terminal velocity. A small child may fare better because their ratio of surface area to weight is larger, she noted, so there is more drag from the air to slow their fall.

So what should you do if you're ever in this unfortunate scenario?

"It's very difficult to react effectively, but if you have the time, try to break the fall — for example, if there is another rock or a tree or something," Demetriades said. "Secondly, try to fall on your feet. You're going to get bad fractures, but these are treatable. You do not want a severe head or spinal cord injury, which will leave you paralyzed for the rest of your life."

In addition, make your terminal velocity as small as possible by making your surface area as big as possible — for example, "by wearing loose clothing or by putting on a parachute or spreading out," Hosoi added. "The second thing is to land on something soft that will give more easily than you will, because when you hit, you don't want to be the thing that is easiest to break. You want to land on a bush or something that's going to break before you will."

As for Vulović's famous case, it is believed that she survived thanks to her being pinned to the main body of the plane by a food cart as she fell and then landing at a particularly favorable angle in thick snow in a wooded area.

Doctors also said her low blood pressure likely made it so she passed out quickly once the cabin depressurized and this potentially stopped her heart from bursting as she hit the ground. High-energy impacts, such as falling from a great height or being involved in a motor vehicle collision, are common causes of heart rupture, where the walls, muscles or valves of the heart come apart. Having high blood pressure can increase your risk of experiencing such an event.