On this episode of "MythBusters"...
Nice.
...Adam and Jamie have a data with destiny.
I'm totally psyched about numbers.
They're testing the myth that
during an underwater explosion,
lying prone on the surface
will increase your chances of survival.
Whoa, look how high that went!
- Then... - Good God.
...Kari, Grant and Tory
check on an ancient armor saga.
I felt that one.
Is the far-fetched theory that paper armor...
You couldn't find me a giant pair of scissors to run with?
...protects well as steel...
That is one dangerous looking machine.
...fact or pulp fiction?
Who are the MythBusters?
Adam Savage...
Come on! Let's go.
Here comes chaos.
...and Jamie Hyneman.
Relax. This won't hurt a bit.
Between them, more than 30 years of special effects experience.
Joining them, Kari Byron...
This should be fun.
...Tory Belleci...
We survived!
...and Grant Imahara.
Stop the car!
They don't just tell the myths,
they put them to the test.
MythBusters 9x12 - Paper Armor Original air date June 29, 2011
Sync by YYeTs.net, corrected by atrn97g www.addic7ed.com
Check this out.
Navy divers who find themselves in the water when an explosion,
like a depth charge or something,
is supposed to go off under water,
are instructed specifically that the safest position for them
to be in, in the case of an underwater explosion
is flat on their back on the surface.
And that that significantly is safer even
than treading water in an upright position.
That's interesting.
You wouldn't think there would be any difference at all.
You wouldn't.
And that's why I think it something that we should test.
I'm up for it.
Navy Seals and walruses are advised that
if in danger of a depth-charged disaster
their best chances of survival is to float on the surface
rather than treading water or diving down.
But would it really make a difference?
Adam, Jamie,
and the bomb squad are prime to find out.
Ultimately, of course, I foresee a large-scale quarry lake
big explosions, very cool high-speed shots,
but where do we begin?
Let's say we start with some underwater shock wave testing here
in the shop and see if we can collect some data,
see if there are any problems,
see if there's anything to the myth.
- Sure. This shouldn't be that hard. - Okay.
We're going to need three things,
a tank full of water, an explosion
and a means of measuring the shock wave.
It sounds deceptively simple.
But setting off and measuring underwater explosions
in the shop is anything but simple.
What are you thinking?
I'm thinking this requires a brainstorming sequence...
A long, narrow tube.
...with an inevitable tense discussion...
It will fail catastrophically.
...obligatory technical jargon...
- 15 PSI. - Equal distance from the...
Center blast pressure?
Seven PSI.
That could work.
...and after a final audio crossfade or two...
And we create our shock wave.
And we've got sensors.
...there's a resolute conclusion signaling a solution.
I think that seems like a plan.
I think so.
This here is our tank. 15 feet tall.
It's going to hold 1300 pounds of water.
Inside that tank we will place four shock sensors.
I will detonate a pistol dead center in the tank.
That pistol will generate a shock wave
that will travel up and down through the tank.
If depth plays no role in the propagation of
a shock wave underwater,
we should see an identical reading between sensors B and C,
because they are each the same distance
from the source of the shock wave.
If depth does play a significant factor
in the force of a shock wave under water,
then we should see a difference in the force measured by these two sensors,
and that's where this story gets really interesting.
But it gets interesting before that
because Jamie has an ingenious plan of a tank.
We're going to need a very tall, narrow tank for this test.
We built one of these before for firing bullets into water.
But let's just say there was a serious problem with that one.
Water is heavy and keeping it contained is a tricky task.
Oh! Criminy!
With that in mind, I've come up with an entirely new way
of building a tank that we've never tried before.
It uses very thick vinyl.
Well, that ought to do it.
You're off.
Another six inches?
It's in.
In a few minutes we're about
to fill that tube with 1300 pounds of water.
Will it hold? I can't detect any leaks.
I hope so.
So does Jamie.
Because nothing scares the Hyneman more
than a mess in potentia.
It's terrifying. Quit yanking on it.
With the tank holding,
they're about to tempt fate by introducing the explosive ingredient.
The role of our shock producer in this small scale test
will be played by this,
a .357 Magnum pistol
to which I'm going to make some modifications
so we can fire it remotely and under water.
Okay, Kari, what do you got for us?
I've got a historical myth.
And I love this one.
Now, in ancient times, even up to the 1800s,
some armies in China actually made armor out of paper.
Paper armor. That is cool.
I mean, paper's the last thing you would think of to make armor.
I like this one.
And the cool thing is the paper is supposed to perform
as well as steel.
Wait a minute.
Paper armor performing as well as steel armor?
I'd like to see that.
That's why I want to test it.
Throughout history,
material science has been at the cutting-edge of advancements in armor.
But is it really possible that
the ancient Chinese manufactured paper armor capable
of performing as well as its contemporary steel equivalent?
To find out, Kari, Grant and Tory are arming themselves
with the facts, and then the armor.
Well, first up I'd like to do some research,
talk to an expert, find out how the paper armor was possibly made,
and what the steel counterpart would be.
Yeah. I mean, when we think of steel,
we think of medieval armor like this.
But Chinese steel armor of the period
may not have been like this at all.
It sounds like we'll need to get some steel armor of the period
and make ourselves some paper armor.
Then we'll run them through some tests
and see how the paper compares to the steel.
I'm looking forward to this.
For the paper amor myth,
I've come to the Napa Valley so that I can talk to Greg Martin.
Now, he is an antique arms and armor expert.
Hopefully he'll have a little insight for me.
And his first interesting insight is that
the existence of paper armor is no myth at all.
Historically, paper armor is traced back to the Tang dynasty.
600 B.C.
Of course, the Chinese were very big developers of paper.
So it would stand to reason that paper armor would develop there.
So how would paper armor likely have been constructed?
By using what we call lamellere,
paper was laminated together into squares
and then attached piece by piece
and then would cover the entire body.
So laminar paper armor really was used in ancient China.
There are records of multiple manufacturing methods and designs.
But the myth is that it was
as effective as the steel armor of its day.
An outrageous claim.
And the team is skeptical, but there is some cause for hope.
Now, we know from historical sources that they used a mulberry paper.
Look at this. You can see the fibers.
This is strong stuff.
What they would do is they would stack layers of it together,
and that was strong enough to stop arrows.
Now, one source told us that
they would take these layers of paper
and laminate it with resin or
some kind of shellac or even glue.
Another source says that they would cover it with a cotton cloth
and sew around the edges.
What we're going to do is take all those techniques,
find out which works best.
Once we have that, then we'll be able to put that up against steel
and see which one does better.
And to test our armor pieces,
we're going to use this.
This is a sharpened tip on the end of a pneumatic cylinder.
Here we have a chunk of ballistic material.
Put each sample underneath.
And then we'll fire the cylinder like this...
and see how each sample performs as a result of puncture.
And the best one will go on to make our final armor pieces.
This is folded paper with cotton.
So the goal is to compare the range
of historically accurate manufacturing methods...
- One. - Look at that!
- Wow! - It actually stopped it.
...and decide which will give this steel
the best run for its money.
Each paper piece, regardless of its construction method,
is one half inch thick,
a dimension discovered in the research.
Lacquer made it more brittle,
and it actually went all the way through.
And although shellac and organic resin
may double up as an effective weapon...
That actually stuck!
...the result that emerges is that hardened squares like lacquer
lack the penetrative protection of the winning sample.
Okay. And folded paper.
Oh, my God. Look at how well that worked.
This absolutely works the best.
Simplicity.
Now that we've found our winning paper construction,
which is simply folded up paper,
it's time to put it up against steel.
So we are going to be putting both of these materials against
common weapons of the time.
We're going to be doing blunt force,
some kind of a club or a mace, a sword, and then finally, an arrow
and see which one performs the best.
Later in depth charge disaster,
Adam and Jamie have a data with destiny.
But first...
That is one dangerous looking machine.
...it's steel, paper and sword.
Our trio of MythBusters have a martial mystery
for oriental history.
Supposedly as a material for making armor,
paper matches steel.
So far the team has discovered
that of all the historically recorded manufacturing techniques,
simple folded squares provide the most protection.
This absolutely works the best.
But they're still skeptical of paper's ability to match steel.
So before they go all out and build a full suit of paper armor,
paper will have to prove itself in an authentic setting.
Greetings, friends.
Though this looks like an entirely authentic Tang Dynasty household,
it is in fact the best reproduction
we could come up with for under $10.
Cue the gong.
And here is how this proof of concept will work.
Paper will go up against steel in a series of weapons tests.
And if the damage to a clay block beneath is reasonably comparable,
only then will they move on to a full-scale testing
with full suits of armor.
Now, the way we're choosing our thickness of armor
is we have done some research,
and lamellar armor was about 1/32 of an inch steel.
As far as the paper armor goes,
we found out that it was about a half inch thick.
And that half inch thick equals about 28 sheets of the paper.
To get things rolling,
Grant wheels out of a familiar robotic swinger.
Calibrated to human swinging speeds,
that's 125 miles per hour for the data divas out there,
she's ready for weapon number one.
So for one blunt force trauma test, we're going to use this.
This is a reproduction of an ancient Chinese weapon,
called "the chewy".
That's going to do some damage, isn't it?
Hopefully.
First up, for a taste of the mace, is the steel control,
the material the mythical paper armor has to match.
Trauma test in three, two, one...
Wow! That did really well.
Yep, the clay indentation is slight and shallow.
But now for the all important comparison.
All right. Let's see how paper armor can do.
Okay. This is the trauma test.
Oh. That did not look good.
That looks like it would hurt.
And a look at the side-by-side impressions
only enforces the impression that
this myth belongs in the waste paper bin.
- I'd rather be wearing steel at this point. - Right.
- I think the steel wins in this situation. - Yeap.
But there are two more chances
to find out if paper cuts it as armor.
I think I just cut my eyebrow.
First, the sword.
That is one dangerous looking machine.
And just for reference, let's first see
what the sword does to the unprotected clay.
- All right. - Okay.
It looks like it went in about an inch.
Now for the cold, hard steel.
In three, two, one...
All right. Do you see here,
the sword hit the steel armor,
and it put a dent in the clay,
but it didn't actually cut through,
wounding the person.
Now we're going to switch out the steel armor for the paper armor
and see what kind of damage it does on the clay.
The result is astonishing.
The damage is minimal.
It's similar to the steel, and a vast improvement
on the inch-deep slice experienced by the unprotected clay.
It only cut like maybe two or three layers.
That is crazy.
Paper for armor?
It could work.
I'm impressed.
It's looking great.
Which brings us to the third and final weapons test.
The arrow.
- Oh, it bounced back. - That was awesome!
Let's see how far it went in.
- That's it. - That's it.
That is less than a quarter of an inch.
So paper has one final chance to prove its mettle
against the metal.
In three, two, one...
And hold on to your skeptic's hat.
Because despite the arrow's penetration into the paper,
the clay beneath survived better
than it did against the steel.
Look at that.
Well, I think the arrow went deeper on the steel armor.
Yep. It's concept proven,
the paper more or less matched the metal.
And this myth can move on.
To best avoid injury from an underwater depth charge,
would it really make a difference lying supine on the surface?
Intent on investigating,
Adam and Jamie will set off an underwater shockwave
and measure it at various depths.
All right. This is my finished shockwave-producing,
remote-firing pistol.
It will fire only blank rounds
because I have put a little shockwave disperser in
so that it disperses the shockwave both exactly up and exactly down.
I put a blank round in it, cock it,
and then from above the water,
I can fire it,
generating the shockwave we need for instrumentation.
To measure the shockwave from the handgun blank
is the final item on Jamie's list:
four pressure sensors held in place by magnets.
Here we go.
He he, it worked!
So what's the water tube going to tell us after this test?
Are we going to get a much higher
blast pressure here than here?
It's an interesting question because the pressure here
is already at 4.2 pounds per square inch.
Up here it's only two pounds per square inch.
And that's just from the weight of the water.
It feels like a bank heist.
So that combined with the explosion,
I think is going to inherently give us a higher
blast pressure down there.
But will that equate to death
while treading water while life while lying flat on your back?
I don't think so.
Okay, we're hot.
The question we're trying to answer here is
whether there's some feature to do with
depth under water and the associated pressures,
the greater the depth, the more intense the shockwave,...
That is perfect.
...the shallower the depth,
the less intense the shockwave and the safer you'll be.
What do I think?
I don't think there's going to be much of a difference.
So both MythBusters are skeptical.
But science is an evidence-based discipline.
This is depth-charge disaster,
small-scale test.
Hopefully not making me too wet.
In three, two, one...
Nice.
Well, the sensors did register a result.
And the tank didn't spring a leak.
But a close look reveals that numbers aren't ideal.
So what did we get?
Well, it's looking awfully noisy,
but we're getting some interesting numbers.
Unfortunately, the close proximity of the walls
of the tank to the explosion is
affecting those pressure waves and creating noise
which is obscuring the measurements that we're looking for.
That noise,
the reflected shockwaves bouncing around in the narrow tank...
Is it still noisy?
...means the peak pressurewave
for each individual sensor is difficult to determine.
Let's run it again.
But three bangs later
and they have enough data points for a pattern to emerge.
All right, kids.
Put down your juice boxes and pay attention.
It's time for the moment you've been waiting for.
It's time to interpret the numbers.
Remember that if there was anything to this story at all,
if depth did play a factor in increasing the force of a shockwave,
we should see that the deeper sensors would give us
a higher reading than the shallower sensors at the same distance.
And that is what we're seeing.
In every one of our tests,
the sensor three readings are higher than the sensor two readings.
Sensor four readings are higher than the sensor one readings.
That tells me at least that in small scale,
it might just be something to the story.
So paper armor has potential.
I think it might be time for us to go full scale.
Let's make armor out of paper
and put it up against steel in a series of challenges.
I love it.
We'll put each of the armor on and then run through a series of tests,
maybe we'll test speed, agility and endurance.
And we'll have to have some kinds of ultimate battle
between the two suits.
Not wearing them. Of course.
Pick a number.
So cue the full-scale monumental mission...
You're a dork.
...to make a full suit of paper armor...
Only 850 to go.
...and the less-taxing task of having a real steel one delivered.
So to put our paper armor to the test,
we're going to pit it against a metal suit of armor
from the same period.
Now, because this is hard to make,
we ordered it from a modern armory company in the Ukraine.
And it's battle ready.
Who wants some?
I also do parties.
Meanwhile, Tory gets busy pulling the paper
armor design together,
a design based on these ancient drawings
and Grant's period-accurate steel replica.
If you look at the steel armor,
the scales have holes drilled into them,
and they're tied together with leather straps.
Plus, they are overlapping.
No way there are no gaps in the armor.
I think we need to do the exact same thing.
Take our paper scales, drill some holes into them,
overlap them and tie them together with cotton cord.
Producing this season's hot new paper armor is a huge job.
So the MythBusters' sweatshop is open for business.
And after a week's hard work,
hundreds of lamellar plates have been sewn together
to form a full suit of armor that,
after some minor tailoring,
will be ready to go into battle.
Kari, I just don't know about this paper motif.
I don't know if the judges are really going to like it or not.
Oh, well. Make it work.
The question is, will it work as well as steel?
To find out,
the team is signing up for basic battle training.
Hang tough!
Now that we have our full suits of armor made,
it's time to put them to the test.
We're going to put our suits head to head
in the types of things that you would find in battle.
Namely, speed, agility and endurance.
Oh, my back.
First event in the Armor Olympics
is the 50-yard sprint with sword.
You couldn't find me a giant pair of scissors to run with?
Well, you will be wearing a suit of armor,
this season's must have safety gear.
Here on "MythBusters",
we are making science.
Cool?
So I'm about to take my speed run in the paper armor...
All right. This is sprinting in paper armor.
Are you ready?
...and I have to say, I do think
that the paper armor is going
to encumber me a little bit
just because I've got the armor right down here where my legs are.
Here we go.
On your mark, get set...
Let's see how I do.
So eight seconds is the benchmark.
And although the paper is undoubtedly bulkier,
the steel is twice as heavy.
Meanwhile, Tory,
looking for revenge for past transgressions,...
fails to dent Grant's defenses.
You call that a kick?
Let's do this.
Now, to make sure that Grant
is testing these armors fairly,
we're going to let him rest
in between tests so that way
he has full energy for each of the runs.
Kind of reminds me of "Raiders Of The Lost Ark".
On your marks, get set...
Honestly, I'm really surprised
at how little difference there is
between the paper and the steel armor.
I can't believe there's only a second difference.
Yep, the bulkier,
more restrictive paper armor
performed fractionally better.
But with so little in it,
conclusions can't be drawn just yet.
Cue test two.
Now for the endurance part of this test,
I will be running a mile through these hills
and then ending up on that side of the moat
at which point I'll try to jump up onto the rope...
and cross over.
So that's the course.
Go!
Now for the time trial in paper.
I don't know if I'll have the energy to fight
when I get there.
With the armor weighing in at close to 30 pounds,
it's tough going.
The running wasn't so bad
in the paper armor. I mean, it is awkward.
You have all this bulk on you.
I have torn part of the paper.
But climbing over the rope...
I'm getting too old for this.
...I thought I had it,
but about midway there,
my legs fell off the rope.
Once I lost my legs...
Can you pull yourself back up?
Do it.
...I knew that was it.
I was going in.
Blip indeed, because paper and water don't necessarily mix.
But luckily, it has a chance to dry out overnight.
Whether it will retain its structural integrity
for the test to come is another matter.
And speaking of tests to come,
Tori's time to beat tomorrow while wearing steel
is just short of 12 minutes.
Coming up on MythBusters, we'll replace this cardboard boom
with the real McCoy.
So where do we stand?
Well, our data's a little noisy,
but it does seem to be supporting
the central tenant of this myth
which is that depth does seem
to be a factor in increasing shockwave strength.
Yeah, but the data's just too noisy.
I don't trust it.
I think we need to go full scale.
- To a quarry lake? - Could be.
Done.
Oh, look at you.
Aren't you Mr. Television.
Come on, let's get to work.
To test this story,
we're going set a series of explosions 15 feet under water
and measure them with sensors placed
at different depths nearby.
I claim this shore in the name of
"MythBusters" and science in general.
For all these to be accurate,
we need to be able to locate the explosives
and the sensors in a precise orientation to each other.
What did you let it go for?
I didn't realize it would pull so hard.
To pull that off, we're gonna use a variety of ropes
and anchors.
All right. That's our sensor array buoy.
The sensor array with its PCB sensors
at five different depths
will be positioned at three distances
from the site of the explosion.
And that spread of 15 data points
is designed to answer the question
how best to survive a depth-charge disaster.
And with a lake rigged with all the relevant anchors and buoys,
the bomb boys arrive.
Now, whenever we use explosives,
we bring in the professionals,
retired FBI special agent Frank Doyle
and the Calaveras County Bomb Squad.
Sporting a look available
at www.shadesanduniforms.bomb!
These are the guys
that will make sure all three big booms happen safely.
Meanwhile, Adam, with his sensitive mast,
is focusing on data acquisition.
This is my sensor mast.
These five devices are my sensors.
In a few minutes I'm going to join them all together and
put them in the water
to make the largest piece of
data gathering scientific equipment
we have yet built and used in the history of the show.
That's no exaggeration.
Attached to a floating rig
will be five high-tech pressure transducers
at five different depths,
all linked to a central command center.
Let's talk about the constants
and variables in this experiment.
As far as the constants go,
we're always going to be using TNT.
We're gonna be using ten pounds,
which is five of these things.
And they're going to be hanging
at 15 feet below the surface of the water
where the explosion will occur.
Boom! Also a constant are the sensors.
They're going to be placed
at five different depths both above and below water,
and they'll be the same for every blast.
I feel safer already.
As far as variables, there's only one,
and that's the distance of the sensor array from the explosion.
Now, we're going to start at 150 feet away
and move progressively closer, recording the readings
that we get off the sensors at each stage.
Hey, look at that, it's working beautifully.
All right.
How are we going to use our sensors
to represent a body lying flat on its back
versus a body treading water?
Here's what we're thinking.
We determine that the torso of a person
lying flat on their back on the surface
has an average depth of about six inches.
We also determined that the torso of a person treading water
has an average depth of about two feet.
Why the torso?
Because that's where the air pockets are.
Thus, that's where our sensors are going.
Yep, it's a gruesome but important detail.
Injuries from underwater explosions are primarily caused
when shockwaves pass through internal air cavities,
such as the lungs and intestines.
Hence the focus on the depth of the torso.
Ten pounds of underwater fun.
Well, everything's prepped.
Yeap, nothing left but an explosion.
Unfortunately, you're going to have to wait for
that explosion for these commercial messages
and perhaps some other MythBusters...
Tori is rested, ready and looking not so hot.
You know what, this steel will protect me from arrows
and getting dates.
Come on, Tori, you can do it!
Go!
The question is how will Tori's time in steel
compare to the 12-minute paper run,
and will he even survive?
There's actually a little jeopardy to this test
because first of all, the run is going to be really hard.
It's going to be slow. That thing is heavy.
This sucks big time.
But climbing this rope over this water?
He's wearing 60 pounds of steel.
He goes into the drink, that's six feet deep.
There's no way you're making it across that rope.
I don't think I'm going to make it.
Somebody stick a spear in me. I'm done.
The weight of the steel was the killer.
Tori took an additional five minutes to complete the run
and then couldn't climb the rope.
So an army traveling any kind of distance on foot
would be at a distinct disadvantage in the heavier steel,
which means paper wins that round.
For the final event in the Armor Olympics, agility,
courtesy of some time bending editing,
Kari will simultaneously tackle the assault course
in steel and paper.
After drying out overnight,
the paper doesn't appear to have suffered any damage.
But it's still just as awkward.
It's definitely not as heavy as the steel armor.
Not a lot of give here.
Okay. Here we go.
In three, two, one...
Go, go, go!
Pick up those feet! Pick up those feet!
On the first obstacle,
the paper already has an advantage.
The weight difference is clearly the key factor.
Halfway into the course
and paper-clad Kari has already opened up a big lead.
Come on, Byron!
Go go go go go go go!
And while crawling, the paper-made will be slowing Kari down...
She's having a little trouble with the sand pit.
...but the steel almost brings her to a halt.
There is no reason to win!
Which pretty much sums it up
for the rest of the agility course.
The paper maybe awkward,
but the weight of the steel seals the deal.
Good work.
So with the first three events in the Armor Olympics complete,
the conclusion is clear.
Paper is outperforming steel.
But now it's the real test.
The battle test.
We're going to use weapons from the period
and see if it can still stand up to metal.
Welcome back.
Let me walk you through our setup.
Out there in the middle of the lake tied to a buoy,
we've got ten pounds of explosives
floating 15 feet below the surface.
Alright, it does nicely.
Great.
150 feet away from our explosives, we have our sensor mass
with five sensors
that detect shockwaves mounted to it.
One above the water and four below
at the following depths:
one at six inches below the water,
this simulates someone lying flat on their back
on the surface of the water;
one two feet under the water,
this simulates our person who is treading water;
one 15 feet below the surface
at the exact level of the explosives;
and one deeper than the explosives mounted all the way
down 25 feet below the water surface.
Each explosion will cause movement in the sensors
which will be translated into electrical energy
which will be sent as data through these wires.
That data will find its final resting place
here in the equipment mended by David Harding
who will crunch our numbers.
After three blasts we'll end up with 15 data points
and hopefully the answer to our question.
Now normally we'd do something like
set off a blast, look at the data,
set off another blast, look at the data,
et caetera, et caetera.
I think we're good to go, huh?
In this case we're not going to do that.
We're going to set off all three of our blasts
in as short a period of time as possible.
Fire in the hole.
We are doing this for two reasons.
One, so that the condition the explosions happen under
is really, really similar.
That makes our data much more consistent.
Fire in the hole.
Second reason is the numbers we're going to be looking at
might be quite subtle.
And only by correlating across all three blasts
are we going to be sure that we're telling a proper story.
Here we go for data acquisition stage one.
Or the first big boom of the day.
150 feet.
In three, two, one...
- Oh, yeah! - Wow!
That was a hell of a thud.
That blast was really unexpectedly cool.
It had three distinct kind of whoops to it, like a whoo, whoo, whoo.
Very cool.
Oh, look at that.
That is just lovely.
I'm always astonished by how fast the shockwave moves.
Yeah, it's done and gone
before you actually see anything happen.
You think this is all the explosion.
And actually that's way after.
That's the aftermath.
Blast one went on perfectly.
And David says we got good data
from all the sensors.
We are going to withhold looking at them for now.
We're going to go right into
blast two from 70 feet.
Okay. That ought to do it.
Firing in three, two, one...
Wow! Look how high that went.
All right. Let's go look at the high-speed.
So what actually happens during an underwater explosion?
Well, the explosion creates
a rapidly expanding gas bubble
that pushes water in front of it.
And that creates a pressure wave.
It's that pressure wave
that we're looking at
because that is what could potentially hurt a human.
But the question is,
does that hurt potential
and your very survival, depend on a difference in depth?
This is truly awesome.
It's pretty.
To answer that, the race is on for numbers
and the third and final data point.
David says we've got good data
from the first two blasts.
Shall we prep for the last one?
Great.
I'll set it up.
All right.
Want to know why we did what we did
and didn't do what we didn't do?
Check out the after show.
Log on to discovery.com/myuthbustersaftershow.
As incredible as it sounds,
paper armor is holding up against its contemporary steel equivalent.
But the team has yet to put paper in front of the firing squad.
Good work.
So now that both steel and paper armor have passed through the agility test,
it is time to see
how well they protect under a full-scale attack.
What we are going to do is set up some mannequins...
Grim up, it's going to get dangerous.
...cover those mannequins with
both armors and then attack them
on a full scale with swords,
arrows and even an ancient gun.
Then we'll be able to find out once and for all,
is paper armor as good as steel armor?
But perhaps paper's biggest test will come not from our trio
of weapon-wielding barbarians,
but a second soaking.
This time from the heavens.
Or more accurately, the condensation of atmospheric water vapor.
The rain may indeed weaken the paper
and favor the steel.
But it's a real-world problem.
If paper is to prove itself as protective armor,
it will have to cope with a light shower.
We're all set.
Now we're going to start with the arrow test
and just throw a barrage of arrows at them.
Remember the "watcha"?
Watchaaaa!
We are gonna "watcha" them.
So "watcha" this.
And so the barrage begins.
Kari, Tory and Grant let loose from 20 feet
at both sets of armor.
And despite being soaked, softened and sodden,
the paper protects our male model mannequins
as well as the steel does.
It totally worked.
- I can't believe it. - That is phenomenal!
It totally worked!
The paper armor is stopping the arrows.
We have not got one arrow to penetrate through.
I mean, it doesn't look as good as the steel armor,
but the important thing is, it's working.
Next up, the sword test.
Slicing, dicing, jabbing, stabbing,
I'm just going to go and try to maim those guys.
Kari, just swing wildly.
Using both hand edge slicing stroke,
and a stabbing action,
Ooh, I felt that one.
Kari finds the dial marked "Crazy"
and turns it up to eleven.
I'll tell you one thing.
It's interesting the sounds you make when you're attacking.
I didn't actually mean to verbalize all the "aaah!"
Working out some issues there?
I'm going to get myself a stabbing mannequin for home.
Because it's really a good way to work out aggression.
And speaking of aggression,
where does that lead the mannequins and the myth?
It looks like it's separating through,
but it's stopping before it even gets halfway through the tile.
That's great.
Yes, the paper armor is working. On any individual stab,
slice or arrow shot,
a previously undamaged scale clearly matches the metal.
But Tori sees a key armor attribute
where steel trumps paper.
Right now the paper armor is
stopping the sword attacks just like the steel armor.
However, after multiple attacks,
the paper armor starts to break down.
It's looking like the steel armor is a lot more durable.
Next weapon.
And this is where we surely draw the line on paper.
Because gunpowder has just been invented.
Okay, Greg.
So for our experiment
we need a firearm that would have been
of the era of paper armor.
What do you have?
Well, paper armor was used up till the 19th century.
Let's try something from the 18th century.
Which is this French flintlock pistol from about 1750.
Okay. Let's do it.
And first up facing the flintlock is the metal...
- Whoa! - Nice shot!
...followed by its fibrous friend.
Now, to assess the results.
Ouch. Did it go through?
It didn't go through!
The paper armor stopped the bullets!
It stops the bullets!
It looks like the steel stopped the bullet as well.
Both these armors are effective against this weapon.
With paper once again in the same league as steel,
this myth requires a further fast forward in time.
So now we're going to try our 19th century gun, the Colt .45,
1200 foot pounds of muzzle energy.
This should put our paper armor to the test.
This is 19th century gun versus steel and paper armor.
Here we go.
In three, two, one...
And neither stood a chance.
Well, it's obvious it punctured the steel
and it looks like it went through the paper as well.
With both sets of armor
succumbing to the souped-up firepower,
it's time to conclude this ancient Chinese conundrum.
OK, paper armor performed the same as steel
with every test we've done,
and it failed in the same place as well.
Yes. It just seems that the guns got too powerful for the armor.
I've really been wanting to do this story for a long time
because it seems so outlandish.
But it's super impressive, paper armor
is actually a viable option in warfare.
Viable, but there is one notable drawback.
As you can see, it doesn't have the same durability as the steel.
But still works.
So this one is plausible.
- Plausible. - Plausible it is.
Unbelievable.
Welcome back.
Jamie and I have been spending
this episode exploring the idea
that if you're in the water
during an underwater explosion,
are far safer lying flat on your back at the surface
than you are even treading water.
We've done small-scale experiments,
we've done large-scale blasts at this here quarry lake...
We have not yet looked at our data.
We have one more data point to get,
one more blast and then we are going to look and see
if it actually correlates to what this myth purports to say.
OK, 30 feet.
Are you good to go?
I'm good to go. Let's do it.
In three, two, one...
Those did score ten pounds of explosives, 15 feet under the water,
130 feet away of where you sit on land, feels exactly like an earthquake.
It all comes down to this.
David's crunching our last set of numbers.
And that's the final piece of the puzzle
that we need to answer our question.
Remember, the question is, during an underwater explosion,
does it really make a difference lying on your back
compared to treading water?
And the threshold number to keep in mind is
What our research has uncovered
is that people exposed to a pressure of 87 PSI or higher,
have a greater than 50% chance of dying.
That's our threshold then.
Anything below 87 PSI milliseconds is alive.
Anything above it equals dead.
And hot off the portable printer,
the figures make for a pair of happy MythBusters.
Remember, Jamie smiles on the inside.
Dude! Check that out!
Nicely done!
It doesn't get any clearer than that.
It totally does not.
I have to admit, we have rarely gotten data this lovely.
We have 5 sensors, 3 blasts,
for 15 separate data points.
And this whole story comes down to two data points.
The sensor we had at six inches versus the sensor we had at two feet
form the blast from 30 feet away.
That blast would have killed you
if you were treading water,
and you would have lived through it
if you were lying flat on your back.
That's the story we came to tell.
And that's the story the data tells.
It's lovely.
It's a definitive set of data all right.
But to really put this myth to bed
Jamie reads you the story called "WHY".
All this data is great,
but what it doesn't tell us is why.
Now, I did a bunch of digging around,
and this is what I found.
Energy doesn't like to transition from one material to another
if they're different.
The more different they are,
the more it doesn't like it.
So in the case of an explosion under water,
as that pressure wave travels towards the surface,
it bounces off because it can't pass through it.
And what it does is
it transitions from a pressure wave to a tensile wave.
And therefore it's able to neutralize a lot of the energy
especially in that surface zone.
And that's why it's safer there.
So soldiers in the military
are told that in the case
of an underwater explosion,
they are far safer if they're lying on the surface of the water flat on their back
than if they're treading water,
what is our answer to that?
That's exactly what we found.
They got it right.
It's confirmed.
Totally confirmed.
Let's go.
I'll tell you, even though that
last blast would have been survivable
if I was lying on the surface,
I wouldn't want to try it.
Yeah, that was like being in an earthquake.
Sync by YYeTs.net, corrected by atrn97g www.addic7ed.com