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In Twister, there is a scene near the end of the film featuring Bill and Jo strapping themselves onto a metal pipe that apparently goes down into the ground 30 feet.

Here! These pipes go down at least thirty feet, if we anchor to them we might have a chance!

Bill and Jo then strap themselves onto this metal pipe while an F-5 category tornado goes over them:

Could someone actually be able to survive a tornado this way? How did Bill know that the pipes went down into the ground 30 feet just by looking at them?

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    That scene always bothered me for the reasons in Skooba's answer. I mentally chalked it up to "Hollywood being Hollywood and getting science wrong as usual." – user9311 Mar 11 '17 at 18:24
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    As anyone knows, the proper way to survive a tornado or a nuclear blast is a refrigirator. – DVK Mar 11 '17 at 22:23
  • You missed the best part, when it's over, the belt is BROKEN, yet they are still there – Kevin Mar 12 '17 at 3:35
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I see many problems with this scene...

On the Fujita Scale an F5 tornado's winds are 261-318 miles per hour...

Strong frame houses lifted off foundations and carried considerable distances to disintegrate; automobile sized missiles fly through the air in excess of 100 meters; trees debarked; steel re-inforced concrete structures badly damaged.

  1. Depth of Pipe: Sure, the pipes may go down thirty feet, but they are attaching themselves to the horizontal piece above ground. The first failure point will be the elbow joints not the line pipe.
  2. Connection method: Again, the depth of the pipe will not matter. What will matter is tensile strength of the leather strap they are tied off on. I am not an expert, but a rough search leads me to believe the tensile strength of of leather is only 570 Newtons, or about 128 pounds which would not be enough to hold two fully grown adults.
  3. Shrapnel: All the wood, glass, and metal flying around at hundreds of miles per hour would certainly be enough to pierce the skin and be lethal. If anything I think this would be the most likely cause of death.

As seen above if whole houses are disintegrated, I find it highly unlikely our heroes made it out of that one in one piece, let alone alive.


A real F5 tornado in 2011 killed 168 people in Joplin, MO. Researchers theorize that most of the damage caused is from substandard building design.

That isn’t true. Properly built, above-ground safe rooms — typically a hardened indoor closet or room reinforced with concrete and steel — are just as safe as underground shelters, says Texas Tech’s Ernst Kiesling, who’s also the executive director of the National Storm Shelter Association. In fact, above-ground safe rooms can be safer because they’re more likely to be used when severe storms move in, he says.

There have been no reports of any deaths in properly built above-ground safe rooms, Keisling says.

For Bill and Jo to survive they would have had to get to a proper shelter.

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    I think their arms may have survived, as they may remain firmly attached to the pipe. But their bodies would likely have been ripped off at the shoulders, and would not survive the landing impact after falling down from however high they were sucked up. Theoretically, with the right hollywood tech, they could grow their bodies and head from the surviving arm :) – Bohemian Mar 11 '17 at 18:34
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    @Bohemian: without shrapnel flying around, you'd need a lot more windspeed to do that. Stuntflyers and wing walkers and whatnot do stuff that subjects themselves to stronger winds at airshows and they usually stay in one piece. – whatsisname Mar 11 '17 at 19:24
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    @Snowman: nah, the greatest pressure drop ever recorded in a tornado was around 1.5 psi, which is equivalent to diving to 3.5 feet of water. You'll definitely notice it, but it will hardly do anything catastrophic to you. – whatsisname Mar 11 '17 at 19:27
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    The leather strap looked much thicker than the 2mm pure leather you reference. You also don't calculate for bonding material or anything. And they never free hang off the strap, so its not just its strength but add on their strength. It's not like they used a dress belt. – cde Mar 12 '17 at 2:14
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    Just a minor quibble, but tensile strength is measured in units of force per area, e.g. newtons per square meter. Claiming that "the tensile strength of of leather is only 570 Newtons" is as meaningless as saying that the top speed of your car is 10 meters. – Ilmari Karonen Mar 12 '17 at 4:27
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I am inclined to think that one would be required to remove debris from the equation before any answer beyond "no" would be possible - as the simplest pieces of debris have shown to be highly penetrative in such a force of nature.

I am certainly inclined to say that strapped in such a matter you would probably flutter around several times which would very likely lead to a fatal clash with the ground, if not some unfortunate whiplash.

4

No.

Twister is a steaming pile of Hollywood horseshit. Almost nothing depicted in this film is realistic.

First to the metal pipe.

We can realistically estimate the amount of force someone will experience in a F5 tornado. The free fall terminal velocity of a human being is approximately 55 m/s (120 mph, 200 km/h). This means that the wind speed has exactly enough force to lift the weight of the human body. Now an F5 starts with 116 m/s (260 mph, 420 km/h) which is the nearly exactly two times the terminal velocity speed. Unfortunately for our daring heroes wind force squares with linearly increasing speed, so the actual force quadruples.

If Bill weighs 1000 N, he is pulled with a force of 4000 N (!). And not with a securely fitting harness used on the thigh like a climber which can actually hold this amount of force, but with an improvised leather strap around the upper torso. If the heroes don't get ripped out immediately, they wish they were because the leather will tear off the muscles and ligaments.

What is also wrong is the convenient floating: Tornado wind is highly turbulent, they will be flung around like laundry (Which is the reason why I did not use the higher fall velocity for being head-on; They cannot hold that position). But the pipe does not even budge or bend which is strange when someone realizes that it is being pulled with the weight of approximately 8 humans.

Next question: What is softer: Tree bark or human skin ?

Well, all the flying debris does that to tree bark (and this was an actual F5): Some ex-trees. The trees that are still present have few branches and almost no bark.

I hope the answer to what will happen to two idiots strapping themselves inside an F5 tornado is now clear: They will be mutilated and flayed alive.

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    Skin has 3 times the tensile strength of bark. And notice how only part of the bark is stripped, which really depends on the condition of the bark. Old, dried bark is easier to strip then the newer, wetter bark, typically seen on the branches. – cde Mar 12 '17 at 16:54
  • @cde Nice to know, but my claim was that skin is softer, not that it is able to withstand more pulling. Does it change the end result what debris will be doing to open skin ? This road was scoured of tarmac, this cow survived the F5 Glazier–Higgins–Woodward tornadoes in 1947. – Thorsten S. Mar 12 '17 at 17:22

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