How Far Can You Fall and Still Survive?


You’re on a plane. You’re bored. You stare out the window at the clouds. You wonder what would happen if you couldn’t resist the urge to open the emergency exit and plummet to the earth below. Is death certain? Or would you pick yourself up, set a broken bone or two, and proceed directly to a mental institution with a great story?

Let’s first toss out some variables that often bog down this fair—albeit morbid—question. Forget Felix Baumgartner, the man who filmed himself jumping from 128,100 feet. He had a cool pressurized suit and a parachute. And let’s set aside what free-fall experts have coined “wreckage riders,” those who have fallen while trapped inside a portion of broken aircraft. (The larger surface area increases air drag, slowing their descent. Still likely fatal, but the odds improve somewhat: Serbian flight attendant Vesna Vulovic fell 33,000 feet this way in 1972 and lived to tell her tale—once she woke up from her coma.)

Let’s instead restrict the question to a single individual without any equipment, encasement, or premeditation. You’ve ripped the exit door open like a lunatic. You begin to fall. What now?

We know for certain a person can survive a fall of at least 20,000 feet. That’s how far up World War II pilot Alan Magee was when he had to abandon his plane without a parachute. He crashed through a glass roof that likely helped spread out the impact. According to James Kakalios, Ph.D., a professor at the School of Physics and Astronomy at the University of Minnesota, how and where you land is one of the major factors in whether you get up from the ground or go 6 feet further into it.

“If you can make the time [landing] longer, the force needed to stop you is smaller,” he says. “Think of punching a wall or a mattress. The wall is rigid and the time of interaction is short so the force is large. People who have survived falls, they’ve managed to increase that time, even if it’s in milliseconds. From one millisecond to three, that’s three times longer, three times less force needed for the same change in momentum.” Magee’s glass landing likely reduced the impact; other survivors have plummeted into snow, trees, or something that can better absorb your landing than, say, concrete.

The other major factor? Slowing your descent. Increasing surface area means more energy is required to push air out of your way, slowing you down. The “flying squirrel” position, body splayed out, is preferred over falling feet or head first. “Increasing that drag is the biggest factor in keeping you alive,” Kakalios says. A parachute’s large surface area is best, obviously. Without one, fall belly down or try tumbling. “Drop a pen off the Empire State Building straight down and it might kill someone. But if it drops sideways, spinning end over end, it probably wouldn’t.”

You’re increasing air drag. You’re trying to land in snow or something absorbent. If you’ve passed out from lack of oxygen at high altitudes, you’ve woken up in time to orient yourself. Magee traveled 20,000 feet—nearly four miles—so you know survival is possible from there. What about going higher?

Kakalios stops short of offering a prediction, citing the numerous variables involved. (“Even how much clothing is fluttering behind you can affect surface profile,” he says.) So we pestered someone else: Paul Doherty, Ph.D., a physicist and Co-Director of the Exploratorium, a learning center in San Francisco, California.  

“As you get higher up, the air gets thinner and thinner,” he says. “You can spin so fast the blood can rush into your head and kill you. Or the friction with the elevation will burn you up. That’s why space shuttles have heat insulating tiles.”

Once terminal velocity (maximum acceleration, usually 120 miles per hour for average-sized humans) is reached, Doherty says, it doesn’t really matter whether you throw another 5000 or 10,000 feet on top of Magee’s 20,000: You’re not going to fall any faster. But start too high up and the lower atmospheric pressure means your blood might start to boil. That’s believed to happen around 63,000 feet, though data is obviously limited, and Doherty thinks it might be as high as 100,000. (NASA mandates pressure suits starting at 50,000 feet just to be on the safe side.)

So falling just under 63,000 feet is survivable, in theory? “Let’s say 60,000, Doherty says. Up to 100,000 if you wake up after passing out. And if your blood doesn’t boil. And if you can impact something.”

Stay on the plane.

What’s the Difference Between Prison and Jail?

Many people use the terms jail and prison interchangeably, and while both terms refer to areas where people are held, there's a substantial difference between the two methods of incarceration. Where a person who is accused of a crime is held, and for how long, is a factor in determining the difference between the two—and whether a person is held in a jail or a prison is largely determined by the severity of the crime they have committed.

A jail (or, for our British friends, a gaol) refers to a small, temporary holding facility—run by local governments and supervised by county sheriff departments—that is designed to detain recently arrested people who have committed a minor offense or misdemeanor. A person can also be held in jail for an extended period of time if the sentence for their offense is less than a year. There are currently 3163 local jail facilities in the United States.

A jail is different from the similarly temporary “lockup”—sort of like “pre-jail”—which is located in local police departments and holds offenders unable to post bail, people arrested for public drunkenness who are kept until they are sober, or, most importantly, offenders waiting to be processed into the jail system.

A prison, on the other hand, is usually a large state- or federal-run facility meant to house people convicted of a serious crime or felony, and whose sentences for those crimes surpass 365 days. A prison could also be called a “penitentiary,” among other names.

To be put in a state prison, a person must be convicted of breaking a state law. To be put in a federal prison, a person must be convicted of breaking federal law. Basic amenities in a prison are more extensive than in a jail because, obviously, an inmate is likely to spend more than a year of his or her life confined inside a prison. As of 2012, there were 4575 operating prisons in the U.S.—the most in the world. The country with the second highest number of operating prisons is Russia, which has just 1029 facilities.

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What Do Morticians Do With the Blood They Take Out of Dead Bodies?

Zoe-Anne Barcellos:

The blood goes down the sink drain, into the sewer system.

I am not a mortician, but I work for a medical examiner/coroner. During an autopsy, most blood is drained from the decedent. This is not on purpose, but a result of gravity. Later a mortician may or may not embalm, depending on the wishes of the family.

Autopsies are done on a table that has a drain at one end; this drain is placed over a sink—a regular sink, with a garbage disposal in it. The blood and bodily fluids just drain down the table, into the sink, and down the drain. This goes into the sewer, like every other sink and toilet, and (usually) goes to a water treatment plant.

You may be thinking that this is biohazardous waste and needs to be treated differently. [If] we can’t put oil, or chemicals (like formalin) down the drains due to regulations, why is blood not treated similarly? I would assume because it is effectively handled by the water treatment plants. If it wasn’t, I am sure the regulations would be changed.

Now any items that are soiled with blood—those cannot be thrown away in the regular trash. Most clothing worn by the decedent is either retained for evidence or released with the decedent to the funeral home—even if they were bloody.

But any gauze, medical tubing, papers, etc. that have blood or bodily fluids on them must be thrown away into a biohazardous trash. These are lined with bright red trash liners, and these are placed in a specially marked box and taped closed. These boxes are stacked up in the garage until they are picked up by a specialty garbage company. I am not sure, but I am pretty sure they are incinerated.

Additionally anything sharp or pointy—like needles, scalpels, etc.—must go into a rigid “sharps” container. When they are 2/3 full we just toss these into one of the biotrash containers.

The biotrash is treated differently, as, if it went to a landfill, then the blood (and therefore the bloodborne pathogens like Hepatitis and HIV) could be exposed to people or animals. Rain could wash it into untreated water systems.

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