What If You Fell out of an Airplane at 30,000 Feet?

30,000 feet, 9,144 meters, 9 kilometers or 5.7 miles – so far, only one person has ever survived a free fall from that height. Would you be as lucky?

On January 26, 1972, an explosion aboard J.A.T. airways flight 367 resulted in the impossible. 22-year-old flight attendant Vesna Vulovic, fell from 10,000 meters (33,000 feet) in the air, setting a world record for surviving the highest fall without a parachute.

How did she survive? Is there a trick to falling out of an airplane and surviving? And what does it feel like?

If you’re a frequent flier, you might want to pay close attention to what’s coming up.

Since the 1940s, there have been almost 50 cases of people surviving falls from airplanes. In all of these cases, the survivors were lucky enough to have something cushion their fall.

Vesna Vulovic, for example, was in the back of the plane when the explosion happened. When the plane broke apart, the tail section remained intact and, pinned by a food cart, Vulovic was prevented from being sucked out into the open air.

The detached tail of the airplane landed in deep snow in the mountains of Czechoslovakia. Vulovic suffered several broken bones, but the airplane wreckage and layers of deep soft snow ultimately saved her life.

The second highest fall without a parachute that someone survived happened in 1943. Airforce gunner Alan Magee’s bomber was hit by enemy fire over France.

His plane burst into flames and propelled Magee out of the plane before he could grab a parachute. Magee fell about 6,700 meters (22,000 ft.).

Apparently, he smashed through the glass roof of a train station and was found hanging from the steel girders that held up the roof. You wouldn’t think that a glass roof would cushion any kind kind of fall, but if it hadn’t have been there, Magee might not have survived.

So if you ever find yourself falling from an airplane without a parachute, grab on to something! Anything! And use it to break your fall.

Of course, that’s easier said than done. When you’re in free fall from 9,144 meters (30,000 feet) in the air, a soft landing is probably the last thing on your mind.

It all happens so fast. From the moment you’re outside of the plane, it’s only about 170 seconds until you hit the ground. During that time you will be extremely cold, and deprived of oxygen.

The average temperature at 9,144 meters (30,000 feet) in the sky ranges between from -40° C to -57° C (-40° F to -70° F).

But you wouldn’t feel it for long, because you’d pass out soon after leaving the aircraft. While all air contains 20.9% oxygen, at higher altitudes there is lower air pressure, so it feels like there’s a lot less oxygen.

This will cause you to lose consciousness, at least for a while. The air pressure will gradually rise as you get closer to the ground, so you would probably wake up again after about a minute of free fall.

As you fall, your speed will increase by 9.8 meters (32 feet) per second – every second – because that’s the Earth’s gravity. Eventually you would stop accelerating and reach a constant speed known as terminal velocity.

This results from a buildup of air pressure below you as you fall, because air can’t get out of your way fast enough; at the same time, the air behind you doesn’t fill in fast enough, creating a sort of vacuum. The difference in the air pressure below you and the air pressure above you creates drag, or air resistance.

When the force exerted by this air resistance equals the force of gravity, you’ve reached terminal velocity, and will be moving at a constant speed. Falling from 30,000 feet, you’re likely to reach terminal velocity at 190 km (118 miles) per hour.

Of course, your actual terminal velocity will depend on your size and weight. The heavier you are, the faster you’ll fall.

But if you spread your arms and legs out wide, you can increase the amount of drag exerted on you. That might slow you down a bit. You’d enjoy it a lot more if you had a parachute though.

Parachutes are lightweight and very wide. A parachute would cut your falling speed from 45 meters (148 feet) per second down to to 5 meters (16 feet) per second.

If you don’t have parachute, it would help to know where to land. Look for somewhere that’s soft, so there’s a chance of breaking your fall. A lot of the people who have fallen from airplanes and lived have survived due to landing in deep snow, or being cushioned by trees or bushes. Unfortunately, a tree can either be really good, or really, really bad.

If you don’t see anything soft below, your best bet is to try to land feet first with your legs together, slightly bent. When you hit the ground, you’ll likely crumple to the side or back.

This is known as the 5 point impact sequence, and while it will be incredibly painful, it will save everything above your waist — mainly your vital organs and your brain.

Of course, these are all just recommendations – tips to make the best out of a bad, and severely unlucky situation. Humans aren’t really built for 9,144 meter (30,000 feet) free falls; and yet, every year we seem to achieve something we thought was impossible. So before your next flight, you might want to pack a four-leaf clover, just in case.

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