MythBusters (2003) s16e01 Episode Script

The Explosion Special

1 [ Birds chirping .]
[ Vehicle approaches .]
Man: You're on a one-way trip on a cold steel rail A one-way trip You ain't got no bail You're on a one-way trip No turnin' back 'cause it's a one-way [ Radio turns off .]
[ Clock ticking .]
[ Brakes squeal .]
[ Ticking continues .]
[ Gears shift, engine turns off .]
[ Ticking continues .]
[ Ticking continues .]
[ Ticking grows louder .]
[ Thud .]
[ Ticking continues .]
[ Heart beating, phone ringing .]
[ Debris clatters .]
You ready for the explosion special? Ugh.
Maybe you could give me a minute.
Ah, you big baby.
[ Whooshing .]
[ Bubbling .]
[ Hisses .]
[ Buzzing .]
[ Crackling .]
[ Clank, whoosh .]
[ Clank .]
Jamie, when we're all done makin' "Mythbusters," how would you like us to be remembered? How 'bout for our promotion of critical thought? And how do you think we will be remembered? - For blowing crap up.
- Yep.
That is why, in this, our final season, we're devoting an entire episode to an explosion special.
What's on the docket? Well, we are finally going to tackle an explosive we have never had any experience with before land mines.
Like this! Oh! [ Spits .]
But first, we have a new twist on perhaps "Mythbusters'" most favorite and famous explosion.
That would be the cement truck.
Yes, it would, and it stars our favorite fictional, honorary Mythbuster, Angus MacGyver.
Let me set you the scene.
Come on, let's go, go! [ Whistles .]
A mail truck has been fitted with a bomb full of dynamite.
Keep it coming! MacGyver brings a cement truck over to the mail truck and starts filling it with wet concrete.
When he gets it above the bomb, the bomb goes off.
The cement seems to prevent the bomb from causing any real damage.
It worked.
I honestly don't know what would actually happen.
Which makes it a perfect myth for us to test.
Three Narrator: When it comes to countdowns - Two - The Mythbusters - One.
- Have an explosive 14-year history.
Bye-bye! [ Beep .]
Narrator: And to sign off their final season in style they're putting a MacGyver spin on an old "Mythbusters" favorite.
Well, there's your problem.
[ Laughter .]
Narrator: To get things rolling, the team decamp to a much-loved location.
If you're gonna blow somethin' up and you need more than just a few pounds of explosives to do it, generally the neighbors don't like it.
And that's why we've come to one of our favorite places to blow large things up lone, California.
That seems about right.
Our plan today is pretty straightforward.
We are going to be detonating two mail trucks.
Why two mail trucks? Well, one, obviously, will be full of wet cement, but our first blast will be empty.
Yes! The Mythbusters postal service.
This skeletal bird with dynamite in his talons.
[ Laughs .]
Why are we detonating an empty mail truck? Well, that's because we can't know if MacGyver's actions had any effect on the blast unless we have something to compare it to.
That's our control.
Narrator: For set dressing, the cop car that MacGyver hides behind is dropped into place.
But the key to this myth is the mail truck's explosive cargo.
By looking at the clip, we've determined that they used about 84 pounds of dynamite.
Now, this right here may look a little bit more festive, but this is actually what 84 pounds of dynamite looks like.
Narrator: To quantify and compare the damage between the control and the concrete blasts, they'll measure two parameters.
First, the shrapnel.
We want to know how dangerous the shrapnel might be, so we are implementing shrapnel-catchers.
We have cut out a ton of plywood dudes that we are going to place on a 30-foot radius between us and the blast so that we can see if chunks of metal fly off, will it kill someone standing that far away? [ Drills .]
Let's mullet it up! You know, while it's universally agreed that [ Drilling .]
MacGyver brought ingenuity and cool problem solving to network television, it's not often discussed what he's done for the mullet.
Business in the front, party in the rear.
Narrator: The second parameter is the pressure wave.
We'll be gathering precise data on the strength of our blast using one of these.
This is a pressure transducer.
Our blasts, obviously, will put out a tremendous amount of energy, most of it in the form of a blast pressure wave.
That wave will meet our pressure transducer.
It'll exert a little mechanical energy on a tiny crystal inside the transducer, called a piezo.
When we hook it up to a computer, it gives us exactly how strong the blast pressure wave was where that pressure transducer was placed.
Having all three of these data points for both blasts oughta give us a really good picture to see if MacGyver's cement made a difference between the control and the cement blast.
[ Siren wailing .]
Mr.
Hyneman, are you ready? Okay.
Arming and ready.
This is MacGyver control empty postal van, 84 pounds of t.
N.
T.
In three Two One.
Boom! [ Chuckles .]
[ Laughs .]
That I think they're still some stuff - flying through the air.
- Yeah.
- Nobody go outside yet.
- Nope.
What goes up comes down.
[ Explosion .]
Yep.
Narrator: You've got hail.
A hail of metal shrapnel Oh, look.
The eagle has landed.
And plywood shrapnel-catchers.
That's gotta hurt.
[ Laughs .]
It's pure carnage for our shrapnel-catchers.
Legs and hands and mullets everywhere.
Narrator: The blast was significantly more powerful than expected.
At 30 feet, the shrapnel damage was clearly catastrophic.
But what about the pressure sensors? Oh.
[ Chuckles .]
Whoops.
It looks like all three of the sensors we had out here are totally busted.
Narrator: With the cables for the pressure transducers shredded, even at 250 feet, they have no control data, and the next step will take some figuring out.
So it's on to story two, where they guys are breaking new ground by going underground.
- So, land mines.
- Yep.
The myth is, if you want to cross a minefield and you wanna do it safely, which I assume you do, the vehicle of choice is a hovercraft.
And that would be because the hovercraft doesn't set them off.
That's the myth.
That's what I think we should test.
You know, I don't think I've ever driven a hovercraft.
Especially over a minefield.
One stick of dynamite.
Narrator: This is a story of firsts.
Over the years, the team has tackled every conceivable explosive tech Except one land mines.
Adam: Wow! Narrator: But first, this story's other first, the state-of-the-art craft in question.
[ Motor droning .]
Narrator: Supposedly, a hovercraft is perfect for safely traversing a minefield because it evenly distributes its weight on a cushion of air.
To find out the truth, our novice riders require lessons.
We got the left and the right steering, and we have the throttle.
That provides both the lift and the thrust.
[ Engine starts .]
[ Motor droning .]
Oh, ho-ho! Narrator: Once in the driver's seat, Adam discovers Whoo! It's surprisingly easy to handle.
[ Laughs .]
He's havin' way too much fun.
Narrator: Yep, and they're also starting to get a feel for how 600 pounds of man and machine could possibly power through a minefield without mishap.
Whoo-hoo! Jamie: Well, they're basically boats that float on a cushion of air, and that cushion of air is retained underneath the boat by a flexible skirt.
And there's an engine that's pumping air down into that skirt.
Now, hold it, hold it, hold it.
Now countersteer.
Perfect.
- Jamie: There you go.
- Yeah! [ Laughs .]
That same fan and engine, though, are also pushing air out the back through these fins, and that provides it with propulsion and steering.
[ Motor droning, Adam laughing .]
- Wow.
- Whoo! [ Adam laughs .]
[ Motor droning .]
Jamie: As far as operating this thing in a minefield, I think this is gonna be kind of like operating a boat in a marina.
Yeah! I think it can be done, but you have to plan ahead, and that's gonna be the key.
[ Filtered voice .]
This is great! [ Laughs .]
That, my friends, is the sound of Jamie Hyneman being enthusiastic.
I don't know about you, but I feel ready to drive this across a minefield.
Let's go make a minefield.
Let's do it.
Narrator: Coming up on "Mythbusters," this explosive Oh! [ Laughs .]
Jamie: It's just a flesh wound.
Final-season spectacular Oh, ooh! I am workin', walrus.
Narrator: Turns back the clock Hey.
Welcome to 1987.
Narrator: And tests the team's limits Ooh! All right.
I'm in.
Of acrobatic ingenuity.
Ohh! That feels [Bleep.]
.
Back at the beginning Go! [ Whoosh .]
That is not enough to blast somebody off the seat.
Narrator: The big booms weren't so big Whoa! Whoa.
Or beautifully captured, and often didn't go according to plan.
[ Rattling, explosion .]
[ Chuckles .]
Am I missing an eyebrow? Narrator: Over a decade later, and the Mythbusters have upped the explosive ante And covered every combination of tech and target Narrator: Except one - Land mines - Yeah! And the myth that a minefield can be crossed by a hovercraft.
How they go about testing one of the world's deadliest military devices is a tricky task.
Pvc tubing.
We obviously need mines to conduct our test, and out of this, I will produce a set of artificial mines.
Now, they won't blow up [ Blows air .]
But that's only half of what a mine does.
The other thing it does is register a certain amount of pressure in order to tell it to blow up.
A mine is really, effectively, a scale A scale that says, "blow up" when a person steps on it, like 150 pounds Look at that! [ Laughs .]
Or a truck, like 700 pounds.
And the soul of our fake mines will be this little metal button.
This is, in fact, a pressure transducer, and it will allow my fake mines to behave just like the real thing in every way except for explosives.
Narrator: While Adam makes the housing for the programmable pressure trigger [ Whirring .]
Jamie replaces the c-4 with an air-powered mortar, designed to give off a safe, movie effect blast.
That right there is the tank, and we'll have a funnel on the end of it filled with stuff that's gonna get shot up in the air.
Pretty simple and straightforward.
We step on the land mine, and off she goes.
Kaboom.
All right.
Narrator: With Jamie's mortar assembled and loaded with fake rubble, it's ready for a demo.
[ Puffing .]
- Whoa! [ Laughs .]
That's great.
Looks pretty good to me.
[ Laughs .]
Narrator: That's the film effect explosion.
Back inside, Adam has a prototype of the pressure pad ready for demo.
So here is the function of our mine.
We've got the body that is the casing, and we've got our pressure rod here.
And down at the bottom is that little pressure transducer screwed into the bottom of our a.
B.
S.
Pipe cap.
And [ pops lips .]
That will work just like a real thing.
Narrator: So while the team mass-produces 20 accurate and programmable land mines, it's back to the MacGyver myth.
Adam and Jamie want to know if this cement solution is cinematically scientific or a made-for-TV tall tale.
Adam: Three, two, one! Boom! Narrator: So far, the control blast didn't exactly go to plan.
Adam: Well, we like to say, "failure is always an option," and it has to be, because we had a total failure of our pressure transducer system.
- [ Chuckles .]
Whoops.
- Oh.
But we do have a plan "b.
" Jamie: Yep.
We're gonna focus on the physical evidence.
Our cutouts tell us the shrapnel was catastrophic at 30 feet.
But we can also compare the strength of the control to the concrete-covered blast by measuring how far the shrapnel flew.
That's a heavy thing, and it shot it about 150 feet.
First, we marked out the more sizable pieces on foot.
That's gotta be one of the farthest chunks.
And then, we get the big picture by air.
This right here is the newest piece of amazing camera equipment that "Mythbusters" has brought to bear on shooting our episodes over the past couple of years.
This is called a dji inspire 1, and we use the inspire to witness our entire debris field in one shot.
Narrator: Yep, from this bird's-eye view, the debris field can be mapped at a maximum radius of 675 feet.
With that stat replacing the pressure transducer data cue truck number two.
This is our 84 pounds of dynamite, and the reason I'm lockin' all this stuff down is that this stuff is lighter than concrete, and it might float.
That way, these detonation cords and things like that won't come out, hopefully.
Similar to the shelves in the original clip, Jamie's placed one bundle of dynamite down low and one up top.
And screwing them to the wooden frame should prevent them from floating free when the concrete flows meaning it's time for man-of-the-moment How you doin'? Narrator: MacGyver.
I like this look.
Maybe I'm gonna try it out.
Narrator: Our mulleted hero springs into action.
Adam: And perfect.
Right there.
Narrator: Matching the clip, he directs the dump truck to unload 8 cubic yards, or 32,000 pounds, of wet cement.
Jamie: It's comin' out.
It looks kinda like a cow takin' a dump.
[ Laughs .]
It really does look like a cow takin' a dump, and I've never even seen that.
Wow.
Narrator: It'll take 30 minutes to fill 'er up, but there's a problem.
Kill it.
What's up? Look at the, uh, bag of explosives that came out from under the table.
Oh, [Bleep.]
.
Narrator: Despite Jamie's precautions What do we do? What can we do? Narrator: 40-odd pounds of primed-to-explode dynamite is dangerously detached.
It has to be secured, and fast.
We can cut a bigger hole and crawl through this.
Narrator: Ironically, they've gotta MacGyver the situation.
With the cement already 12 inches deep, they can't go through the doors.
I'm sorry, but I have to take off the MacGyver wig.
Narrator: The cement is rapidly setting.
The sun is heating the truck interior to a stifling 150 degrees Ah, [Bleep.]
.
Narrator: And there's an unexploded bomb to be manhandled.
Whew.
All right.
I'm in.
Ohh! That feels [Bleep.]
.
Narrator: All in a dangerous day's work for the Mythbusters.
Right, I just remembered this is 40-some-odd pounds of t.
N.
T.
Gonna handle it gently.
All right.
Narrator: To make sure they match the clip Thank you.
The loose bag has to be submerged under the concrete, so Adam boxes it in, and with some 2x4, screws it down Yeah, you aren't going anywhere.
Narrator: Before escaping with a brand-new pair of concrete boots.
[ Grunting .]
Yes! Ugh.
Ohh! Yes! Ahh.
- Nice work, Houdini.
- Thank you! [ Laughs .]
How to escape upside down out of a container full of concrete and explosives.
Narrator: And with that Let's clear the area! Let's start pumpin'! Narrator: Macgyver's back on track to save the day.
Or is he? This is a new problem, like we needed more.
It might be pushing out the sides of our truck and leaking out.
32,000 pounds.
That's 16 tons.
My guess is, that's more than this truck was built to take.
Wow.
That is a lot of pressure on those doors.
That's a lot of mail.
Narrator: In the clip, the truck wasn't affected by the extra weight.
But in real life, it's only just holding together.
Let's kill it! Narrator: The team has to move fast before it fails.
So where we are right now is that we have just, just, just covered the bomb with concrete, and we are working very hard to, as the bomb techs would say, de-ass the area.
Trying to get all the equipment out.
Then, we'll get all the people back to the bunker.
Then, we're gonna blow this puppy.
Jamie: [ Filtered voice .]
Three, two, one.
[ Click, explosion .]
Wow.
Hey.
Welcome to 1987.
Here's the problem.
MacGyver is confronted with an 84-pound bomb.
Keep it comin'! He convinces a local cement mixer to back up to the mail truck and fill it full of cement.
The question we wanna answer is You ready to do this? Would his cement have made any difference? - Are you ready? - I'm totally ready.
In the clip, it looks like almost nothing happens at all.
Okay.
Wet concrete explosion in three Like, there's a boom, and the truck jumps, and there's a little fire, and that's it.
Two That would be the most ideal outcome.
One.
- [ Click .]
Wow.
That totally went off, and all the dummies are standing.
- It works.
- [ Bleep .]
That worked gangbusters! It did.
Narrator: It's an astonishing result.
As per the clip, the explosion was almost completely smothered.
That is amazing.
I'm completely blown away.
Jamie: Let's face it.
Some of the stuff we've seen on "MacGyver" is downright silly.
But this one turned out to be, actually, darned impressive because, you know, it looks exactly like what we saw in the clip.
Most of it appears to have been absorbed by the mass of the concrete.
It it just absorbed it.
This is our debris field.
It's - Yeah.
- One big thing.
A darned effective technique.
I never woulda thought it.
Narrator: After inspecting the onlookers, the news keeps on getting better.
Well, I'm standing here with our shrapnel-catchers, and what you might notice is there's a great difference between them for this blast and the previous one.
Yep.
Every single one of them [ Boom .]
Is still standing.
That was incredible.
Maybe the most surprising result we've had in a long time.
Narrator: But Oh, shoot.
Couple of unexploded sticks of t.
N.
T.
There.
Narrator: Cancel the cake and put the "confirmed" party on hold.
A closer look reveals the muted explosion was down to a misfire, not MacGyver.
It seems the concrete dislodged the detonation cord from the dynamite.
Remember how I said that failure is always an option? It is starting to feel like the only option.
We found a garbage bag full of unexploded dynamite.
And then, Jamie, like a surgeon, used the forklift to peel the front off of this mail van.
Stop! Stop! And that's when we found another garbage bag full of unexploded dynamite.
- Is that the other bag? - We gotta redo it.
Yep.
Our best guess is that we detonated two sticks of dynamite.
That's not the blast we were looking for.
So here's what we've gotta do We have to come up with a methodology for making absolutely sure that dynamite goes off when it's under the cement.
Once we have that methodology worked out, we are going to implement it, bring back in a cement truck, fill another mail truck with cement, and try this for real.
Comin' up on "Mythbusters," we test déjà vu all over again.
Narrator: While the guys get set to fix their MacGyver missteps, over at Alameda, it's time to lay the minefield for their hovercraft to cross.
Jamie: So we've chosen a minefield that is about 50 feet long and about 8 feet wide.
This is not testing whether we can evade these mines.
This is testing what happens when we go over them with a hovercraft.
So we feel that this configuration should guarantee we're gonna do that.
- Every 3 feet.
- Okay, there you go.
Narrator: Yep, this deadly dollar-sign design will ensure that when the hovercraft crosses, it'll hit most of the mines.
Now, can Jamie dig it? [ Whirring .]
Yes, he can.
Nothing makes the Hyneman happier than the right tool for the job.
Adam: Beautiful! Now, you may be wondering why we're doing all of this digging.
That is a beautiful machine.
Because mines You usually just put them in, and they're sitting there, waiting to release their horror upon the world.
Our mines are not autonomous mines, right, because we actually have to wire them up to a system, allowing them to be switches for our air mortars.
So allow me to introduce you to our mines.
Yes! Remember me building this in the shop? Well, now it's got a paint job and a title and a wiring bus so that we can wire these mines to our central system, which will allow us to adjust the pressures they go off at and set off our mortars.
Narrator: And while Jamie spends the day digging the trenches for the 20 mortars and mines, Adam [ Laughs .]
Narrator: Decides to test-drive the hovercraft.
[ Laughs .]
Yeah! - Narrator: One or two - [ Laughs .]
- [ Chuckles .]
- Narrator: Or six [ Adam laughing .]
- Oh! - Narrator: Or seven more times.
[ Motor droning .]
Yeah! [ Laughs .]
I keep waiting for Jamie to come on over and go, "stop screwin' around.
" I'm doin' all this digging.
It's time to get to work.
" I'll be like, "I am workin', walrus!" Narrator: Hovercraft high jinks aside, laying this high-tech minefield is a mammoth 2-day undertaking.
I have to tell you, this is one of the more complicated builds we have ever embarked upon.
We've spent a couple of days now digging, pressurizing, mining, mortaring, wiring and testing, all to what end? To build a functional yet non-lethal minefield we can test with.
And the most important part of this minefield is this the mines.
They're activated by a small pressure transducer that acts like a scale, and we can have it set off the mine at whatever pressure we decide.
Jamie: And when they're activated, these fancy mortars that we've buried go poof.
[ Puffs .]
- Whoa! Adam: And the beating heart of this operation, the thing that joins all of our mines and all of our mortars together and makes them functional, is about a half-mile of cat 5 cable, all terminating here in this rats' nest, which our honorary Mythbuster and electronics and metering specialist, David Harding, claims will allow us to adjust our mines to be set off by any pressure that we choose.
Narrator: And to find out if their complicated setup is working, they're first testing it on foot.
Cue the designated dead man walking.
Now, I could just walk out there and step on one, but where's the fun in that? I'm gonna walk this minefield blindfolded while being guided to doom by Mr.
Hyneman.
[ Amplified voice .]
Don't worry.
I'll watch your step.
[ Chuckles .]
All right.
Okay, David.
Arm the system.
System is armed.
Narrator: From the control center, each mine is calibrated to go boom at 35 pounds of pressure.
One light step, and Adam will feel the full force of a movie effect explosion.
This is weird.
I gotta say, I, uh, know this is totally safe.
Commencing walking the minefield.
Like, I won't get hurt by the mortars that we made, but it's a little nerve-racking.
Jamie: Now, veer to your right a little bit.
[ Heart beating .]
[ Clank .]
Oh! Oh! - [ Laughs .]
- Ah, it's okay.
It's just a flesh wound.
Narrator: The minefield is scarily accurate and completely safe.
Oh! Oh! [ Spits .]
There goes a leg.
Oh, you've still got another one.
Narrator: And when Adam recovers from his gruesome fake death Ahh! [ Laughs .]
Narrator: They can reset the field for vehicles.
Can I be dead yet? Aah! Ah, you big baby.
I think I'm dead.
Let me remind you, we're testing the myth that a hovercraft can traverse a minefield without incident, that it won't set off any of the mines.
Whoo! But this required us to answer the question of what, in fact, is a mine? There are thousands of different kinds, and they're set off by many different things.
Some are set off by electromagnetism, some by vibration.
But the most common of all mines is set off by pressure.
That's the kind we decided to go with.
Oh! [ Laughs .]
It's effectively a scale with a bomb attached to it.
[ Clink .]
Oh! Aah! Ah, you big baby.
Narrator: So after their successful systems test, the team recalibrates the mines to an anti-vehicle setting and prepares for a control comparison.
All right, David.
So we set the mines to 300 pounds.
- All right.
300 pounds.
- Excellent.
Narrator: Before the hovercraft is sent into battle, Adam's Jeep, with fake plastic mini-gun, will be used as a control.
Jamie: This is where the rubber meets the road.
It's time to do our vehicle versus mines test.
All right, Jamie.
You ready? Starting the engine.
[ Engine starts .]
After we see what happens with that, it'll be time to move on to sending our hovercraft across the same course.
Commence the vehicle mine-setting test in three, two, one, go.
Narrator: The Jeep weighs in at just over 3,000 pounds.
- [ Laughs .]
- There goes one! Narrator: And one-quarter of its weight, 750 pounds, is focused through the relatively small contact area of each tire, easily setting off Gettin' my car dusty! Any of the mines they cross.
Jamie: Now, in the case of the hovercraft, not all of its weight is concentrated into one small area.
Well, that worked quite well, didn't it? I guess now it's time for the hovercraft.
Jamie: So the question here is, is that weight, or that down-pressure that it's exerting on the ground, enough to set off one of these mines? My prediction is that the hovercraft is gonna make it just fine.
Even though it weighs, fully loaded with a person, over 600 pounds, I don't see it exerting 300 pounds down on its underskirt.
It's just I don't It's not gonna happen.
Narrator: We're about to find out.
With Jamie in the hot seat, and a high-tech minefield rigged and ready to blow, can a hovercraft really float through an anti-vehicle minefield? Oh, yeah.
Here it comes.
[ Motor droning .]
Oh, yeah! Yeah! It didn't set off a thing.
That was awesome.
- Yeah! - [ Laughs .]
Narrator: That was smooth, explosion-free sailing.
Oh, yeah! Narrator: The s-curve layout ensured Jamie crossed a majority of the mines, but not a single one went boom.
Yeah! You wanna come back around for a second run? On my way.
Maybe a little slower this time.
Yeah! Narrator: Despite reducing speed, giving the mines more time to register the passing hovercraft, the Hyneman gets away unharmed.
[ Laughs .]
Not a thing! That was beautiful! Yeah! Well, there ya have it.
We drove across a minefield with a vehicle, and we're setting off the mines.
The hovercraft, not so much.
[ Laughs .]
I was right! I like being right Every now and then.
Look, it may seem counterintuitive to you that a 600-pound hovercraft can't set off a mine engineered to go off at 300 pounds, but this myth is all about the exact kind of pressure.
A human foot, a car tire Those are point sources of pressure.
But the hovercraft is distributing its weight across its entire footprint, across the entire cushion of air that it's riding on.
That's why it can't set off our mines, and that's why it is the perfect craft for making its way across a minefield.
Narrator: But it still weighs 600 pounds.
[ Engine starts .]
How well does it spread that load, and can a hovercraft cross any minefield at any pressure setting? Now, it's the moment of truth.
Our minefield is set to an anti-personnel pressure.
That is 35 pounds to trigger our mines.
I've already walked it and shown that I'm plenty to trigger it.
Okay, Adam.
You're good to go.
All right.
Here we go, traversing a minefield in a hovercraft set to anti-personnel setting in three, two Here we go! [ Motor droning .]
[ Adam laughs .]
Jamie: Same thing.
No mine action.
Yeah! That is awesome! Narrator: The mines, set to go off at the lightest footstep, are once again unmoved.
Adam then does his best to linger with several 360s.
Jamie: Yeah! Can you hold it one spot? [ Laughs .]
Narrator: But the hovercraft and its cushion of air defies death from below.
[ Motor droning .]
[ Laughs .]
Whoo! At this point, it's looking mighty good for this myth.
But are we done? Come on.
You know us.
You know we're gonna take it to the most extreme place we can.
That's what we're about to do.
So we've set this to go off at 5 pounds.
The easter bunny could set this off.
[ Whoosh .]
[ Laughs .]
Okay, here we go.
Narrator: It's the ultimate test for this myth.
The Hyneman and hovercraft are 120 times heavier than each mine's threshold.
But once again, they float serenely across, unharmed.
Yeah! [ Laughing .]
Didn't set off a single mine.
That is beautiful.
I love it.
Jamie: So how does this work? Well, the answer's in the numbers.
If you divide the weight of the hovercraft by the contact area, you get about 0.
06 pounds per square inch of downward pressure, so there's not nearly enough pressure per square inch.
Well, I gotta say, I think this is about as easy a myth to call as we've ever encountered.
- Yeah, it's confirmed.
- Totally confirmed.
The hovercraft is the absolute vehicle of choice for traversing a minefield.
Sure is.
I gotta figure out how to get myself one of these.
[ Starts engine .]
What? Oh, I'm sorry.
I can't hear you.
Are you [ Speaks indistinctly .]
[ Motor droning loudly .]
How am I supposed to get out of this minefield?! Narrator: Coming up on this explosive final season farewell 84 pounds of dynamite, 185 pounds of pure man.
Narrator: Jamie brings the big boom.
One.
Go! [ Explosion .]
Jamie: Yep.
This is the "Mythbusters" number-crunching countdown.
- Three.
- Three.
Narrator: Synonymous with the show, the teams racked up an impressive number of countdowns - One.
- One.
920 of them.
They've used 18 tons, and more than eight types of explosive.
The most famous was 850 pounds of anfo And the biggest 5,000 pounds.
Jamie wants big boom.
But mostly, it's been an epic orgy of operatic carnage.
Whoa! [ Laughs .]
[ Flames whooshing .]
Looks good.
All right.
[ Gears shift .]
It's the last thing that truck will ever do.
If you're just tuning in, we've been messin' stuff up all over the place [ Boom .]
Unexploded t.
N.
T.
There.
And, in the process, have had a few of our MacGyver moments.
Aah! Yes! That's a mail truck.
Inside of it 84 pounds of dynamite.
Any minute now, we're gonna find out just how MacGyver we are.
Narrator: But first, this time they got to ensure everything goes, "boom.
" The last time, we had some bundles of dynamite that were sitting underneath the table.
Well, it didn't work so well.
Adam: Our best guess is that we detonated two sticks of dynamite.
Jamie: This time around, I'm gonna be putting our dynamite inside a box that's made out of 1-inch plywood, and it's gonna be completely sealed and anchored.
It's gonna work this time.
Narrator: It will explode, but will the cement smother the blast? [ Laughs .]
There are a couple of different things to think about - That's our package? - That's your package.
And the first is that that concrete is heavy, and it's gonna absorb a lot of the explosion.
84 pounds of dynamite, 185 pounds of pure man.
On the other hand, there's something known as "water hammer" - There we go.
- Push! Good.
And that's what happens if you close a tap really quickly.
And it can deliver a hydraulic shock to the plumbing, which can actually rupture it.
[ Laughs .]
That is beautiful.
Now, this concrete could deliver something like a water hammer to the exterior of the truck and bust it up really efficiently.
There we go.
Now, whether that does it more efficiently than it did without any concrete in the mail truck, that's what we're about to test.
That's it.
Let's cap it and get out of here.
Okay.
Narrator: It's been one of the most testing test setups in "Mythbusters" history.
All right, sir.
Are you ready? I'm ready.
I'll go ahead and arm it.
Narrator: But they're primed to finally find out if MacGyver's quick-thinking cement solution would've saved the situation.
This is MacGyver mail truck filled with cement and 84 pounds of dynamite, in three Two One, go! It made a jet straight up.
That was a thud.
[ Laughs .]
Truck's all gone.
Narrator: The truck was completely destroyed.
Well, there's your problem.
Narrator: But there is evidence that the concrete altered the characteristics and intensity of the explosion.
This is really interesting, Jamie.
In that first blast, there was a shock wave.
And it knocked all the legs of our shrapnel-catchers off.
But I'm looking at the shrapnel-catchers that are nearby.
They're mostly intact.
So I'm gonna go out on a limb and say there was not a significant shock wave emanating out.
It looks like probably most of that force went up, and what was coming out was all shrapnel.
This is interesting.
Unlike the control, this time, there's a hole in the ground where the truck used to be Wow! We made a crater.
And a debris field at 250 feet.
It's not nearly as widespread.
It's less than half the size of the control.
It makes sense, if you think about it.
Most of the concrete surrounded the explosive, meaning that the energy was directed up and down instead of outward towards the shrapnel-catchers.
Narrator: Yep, but although the plywood passers-by weren't ripped apart They were hampered.
Adam: Let's face it.
The concrete may have altered the direction of the pressure wave But it didn't save the day.
The shrapnel-catchers are riddled with holes.
The aggregate in the concrete, the loose rocks It all became a lethal shower of death.
And the truck did not survive in any way like it did in the clip.
Found the back door.
This one's pretty easy to call.
Adam: Yep.
All right, Mr.
Hyneman.
Time to call this.
Did MacGyver's concrete technique alter the blast? It did indeed.
Did it protect people in the vicinity? Not at all.
No.
Uh, does it match the clip that we saw on the TV show? No.
No.
I think the call on this one is pretty clear.
- It's busted.
- It's totally busted.
You know, at this point, we've probably blown up more weird crap than anybody alive.
[ Chuckles .]
Yeah.

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