All language subtitles for The.Mightiest.S03E05.Monsters.Of.Rock.1080p.AMZN.WEB-DL.DDP5.1.H.264-RAWR_track3_[eng]

The hardest jobs on Earth

demand the mightiest machines,

hammering foundations...

We're out there ripping and
tearing all the rock out.

...scaling boulders.

It's such a rush.

...and battling rock beds.

This is where
the power hits the ground.

Meet the monsters of rock.

A constant roar
echoes off the coast

of Sault Ste. Marie, Michigan.

Squadrons of steel titans
attack the shoreline,

hammering, crushing

and smashing their way through
bedrock and concrete.

It's like playing
in a big sandbox all day.

You get to play
with bigger toys.

Fifty machines

moving over 900 tonnes of rock
every day.

Just a constant
movement of dirt. I love it.

These mechanical
beasts need to be tough enough

to tackle one of the biggest,

most demanding
demolition jobs in the world.

The excavator,

the jaw crusher,
the trencher -

they're stripping
things down to bedrock

to make way for a new lock in
the St. Lawrence Seaway,

the gateway to Lake Superior,
the Soo Locks.

It's hard to overstate

how important
the Soo Locks are

to North American
steel production.

About 78 million tonnes of cargo

pass through here each year.

We refer to the Soo Locks as the
linchpin of the Great Lakes.

All of it
carried by over 7,000 ships.

If ships can't follow
this path through the Soo Locks,

they have to move
material over land

and then downriver
to the Atlantic Ocean.

costing millions,

if not billions of
dollars in delays.

The old lock has
outlived its usefulness.

A new lock, wide enough for the
largest vessels on the lake,

is needed.

These machines are here
to make sure that happens.

Shipping freighters
are depending

on this project to continue
their essential passage

through this waterway.

With a worksite this large,
a lot of moving parts,

a lot of swinging machines...

These demolition
monsters remove over

408,000 tonnes of rock before
new construction can start.

But they're not
throwing it all away.

A lot of this rubble will be
reused during reconstruction.

All of the materials on site

are repurposed,
whether it's rock or concrete,

will be ground and used for
aggregate and backfill.

When it's time
to tear things up,

the excavators are the
heavyweights on the front lines.

Weighing in at
a staggering 63 tonnes

and armed with a hydraulic
hammer - or 'hoe ram' -

that pounds the rock

at a bone-rattling rate
of 540 blows per minute...

...even the hardest stone
is pulverized in minutes.

It'll tear down the old lock,

the old concrete, the rock
that's underneath and behind.

But a giant hammer
is only as good as its head,

and this one is
easily the meanest weapon

in the war on rock.

This part right here
helps contact the rock.

This is the
chisel piece right here.

That's why they
have a shape like that.

Helps you get more
penetration into that rock.

When you're working
with hard rock,

you need top-tier tools to
cut down on wear and breakage.

The chisel,
it's made of a heat-treated,

high-strength steel

that minimizes
the risk of weak spots,

which will cause cracks,
leading to catastrophic failure.

This is the toughest two feet
in the world right here.

The excavator is designed

for rugged conditions
and extreme environments.

It's driven by an engine

that delivers the horsepower of
a high-performance sports car.

But in the world
of rock crushing,

performance
isn't measured in speed;

it's measured in brute force.

The machine's
hydraulic system generates

a significant mechanical force

from its 436-horsepower
high-performance engine.

That force is transmitted
through pressurized fluid

to the hoe ram's
hammering piston.

Although the machine's
power is brutal in nature,

it does require
a delicate touch.

Rock excavation on this project

is a lot like doing surgery
with a sledgehammer.

So, we're out there ripping
and tearing all the rock out...

...and then, when you
get down to the bottom,

it turns into surgery
with a large machine...

...where you're
trying to take out

just a few inches of rock
to get that flat foundation

to be able
to pour concrete on.

The bedrock beneath the
foundation of the Soo Locks

is called
Jacobsville Sandstone.

It's a very thick sequence
of red sedimentary rock

lying over Precambrian rock.

Engineers have gone
to great lengths

to design the new passage.

So, the demolition team
must do their part

to make sure everything

is dismantled carefully and
efficiently for the project.

We have two active locks

that are really important

to the US economy
and ship traffic,

and then we also have
a lot of historical buildings

and historical
structures on site.

So, we really wanted
to get away from blasting.

At other sites,

there's no denying
the speed and power

of high-explosive rock removal.

But the new lock
is surrounded

by so much life and
infrastructure,

the demolition crew
must rely on their machines

to get the job done.

While controlled explosives

have been used when
absolutely necessary,

the bulk of the work has been
handed over to the machines.

The advantage of using

a lot of these excavators is

you can put a lot
of different machines

in a lot of different areas
and do it a lot safer.

The Ojibwe First Nations peoples

were the first to negotiate

the six-and-a-half meter
change in elevation

between Lake Superior,
Michigan and Lake Huron.

As trade increased
in the area,

larger and larger
boats became more common,

and moving them across
the lakes became more difficult.

And ultimately,
it leads to the construction

of the lock, in 1853,

to facilitate
the transportation and voyage.

The Soo Locks
officially opened in 1855

and have been operating
and improving ever since.

This current demolition

is just another phase
in their evolution.

But before
the demolition started,

this entire area
was underwater.

So, to bring the machines in,

they had to come up with
a way to get the water out

and keep it out.

The solution, cofferdams.

A cofferdam is basically
a giant waterproof wall

that you build in the water.

These temporary barriers
hold the water back,

so that the site can be made
safe and the work can continue.

Two cofferdams
were initially installed

at either end of the lock.

But as the site grew, more of
these barriers were needed

to keep the water out
so demolition could continue.

Pumps remove
181 million litres of water.

The cofferdams make
demolition possible

in the most
impossible locations.

But the work of pumping
that much water out

and managing the overall
water level of the site

is the key to the system.

Keeping a dry
workplace is a constant battle.

All the water gets pumped out

to the St. Mary's River
or Lake Superior.

In total, we have about
three miles of pipe

and 16 different pumps
collectively pushing water,

four feet a second, out to the
other side of the cofferdam.

Right now, we're pumping
about 2,200 gallons per minute,

which is about
3.1 million gallons per day.

That's more water
than four Olympic-sized

swimming pools a day.

With the water held back,

another mechanical
beast gets to work.

one with an endless
appetite for rock.

It can eat bedrock,
dirt, concrete, limestone.

Pretty much anything
that it'll eat,

besides metal, she'll eat it.

The rock crusher is massive.

It can pulverize the material
at a punishing rate

of 550 tonnes per hour.

In a 12-hour workday,
that's roughly the weight

of 3,000 monster trucks.

Right now, you got the
excavator loading the crusher.

It's coming down the chute here,

down the feeder box,
into the grizzly bars.

The grizzly bars are
a simple sorting system.

Smaller pieces
fall through the gaps

of impact-resistant
metal grates,

onto a conveyor belt,
where they're easily ejected.

The large rocks rumble
across the vibrating feeder box

and grizzly bars,

and then fall into the
enormous jaws of the crusher.

Inside, rocks are smashed

between a fixed
and moving plate.

The moving steel plate
crushes the rocks repeatedly

as they fall through
the narrow opening,

reducing the boulders
to mere fragments

as small as ten centimetres.

The rock's just going to get
smaller until the size we need.

You know, it's just going to
go down to the jaws,

start getting popped
all the way down

to the size that
we got it set at.

All that rock smashing
has a mesmerizing effect

on the people who
work these machines,

who have a passion for what
these mechanical monsters

can do each day.

I've been running equipment
in dirt for 12 years now.

I just fell in love
with it and I knew

this is what I wanted to do
for the rest of my life.

Part of the crushed material

is being used to
fill in the old lock,

while the rest will act
as a windbreak for ships.

Being able to keep the
material on site, crush it,

and reuse it is a big benefit.

Repurposing the rock
eliminates the need

to truck and ferry tonnes of
material off the work site.

It's a great way
to be more efficient

when your timelines are tight

and the eyes of
the community are watching.

Following
the rock crusher's assault,

a new machine
rolls into action.

Enter the trencher,

a surface mining titan that
hungers for only one thing...

...grinding up rock.

And its weapon of choice is a
ferocious, gnarly-toothed barrel

that can chew up
over 100 kilometres of rock

in a 12-hour workday.

This colossus
demands respect.

This machine
shakes very violently.

It's not an easy ride.

It feels like you're
riding a bull all day.

The trencher or surface miner,

is a 100-tonne behemoth
of rock-ripping action.

We're gonna rev up.
Once we up to speed,

we're going to drop
the boom and...

...we're tearing up some earth.

We're excavating
all this rock down

to get the rock all flattened
out for a new foundation.

So, using a big drumhead
allows us to flatten that out

and get that prepped
and ready for concrete.

The 4.2 meter wide
barrel, or drum,

is equipped with
carbide-tipped steel teeth.

A carbide is a mixture of carbon

with other metal elements,
often tungsten.

The addition of carbon makes a
new metal significantly harder

and more wear-resistant.

In this case,

the teeth stay
sharper for longer

to keep on
tearing up the earth.

The teeth are
designed to chew up and spit out

the hardest of rock.

They can dig a trench
up to one meter deep.

On this drum, you're
going to have over 150 teeth

that are grabbing the ground
while this thing is rotating.

This is where the
power hits the ground,

and this is what's going to
turn hard rock into rubble.

Hammering rock is hard work.

But on the Soo Locks project,

their opponent
is particularly stubborn.

Jacksonville Sandstone

is a difficult enemy
for the surface miner.

It's a well-cemented,
coarse-grained

red sandstone that will
eat up lesser machines faster

than they can break the rock.

And any breakdowns

could lead to
a landslide of problems.

You can tell
the machine's doing good

when it's not hopping
and banging super loud,

and when it really starts to

hop and bang is when you really
need to change some teeth out,

when they're getting worn.

Maintaining your machines is key

to a smooth
demolition operation.

These machines take a beating

in harsh, demanding,
and dusty environments.

If crews aren't
looking after things properly,

it can lead to safety issues,

causing downtime
and major repairs.

But before the ground
crew can inspect the teeth,

they need to
give them a rinse.

Right now,
I'm cleaning off the drum

because the tips
are full of mud,

and we've got to clean them
to make sure they're not broken.

Every bite takes its toll.

I'll have my ground guy

change out the teeth while
I'm rotating the drum for him.

It takes
some heavy-duty dentistry

to yank these rotten teeth.

Sometimes, you gotta knock it a
little bit loose, so it spins,

put the prong up there...

...and it just pops right out.

Grab a new tooth,

put it there...

slide it back on...

...and it's back in.
Now, you got a new, fresh tooth.

With a new set of
chompers in place,

the trencher can
get back to dinner

and shaking its operator
right down to the bone.

I'm sitting in this machine,

running it for ten hours a day,
six days a week.

It's a little hard walking some
days, but it's all fine.

It's a dangerous game.

Amidst flying debris

and bone-crushing equipment, one
wrong move could be disastrous.

When you put labourers,

operators, excavators,
all in the same hole,

you know,
there's a lot of hazard.

Our biggest motto is, you know,
just watching out for,

not only yourself, but your--

you know, be your
brother's keeper.

More than a century ago,

hundreds of men toiled against
this rock with crude tools

and pickaxes.

Now, these colossal machines

are the ones who
reshape the landscape.

Their thunderous work
serves a greater purpose,

ensuring that trade continues

to flow through
this crucial passage.

Water has been
critical to transporting goods

for thousands of years,

and that's not going to change.

The Soo Locks will be
integral to our movement

for hundreds of years to come.

These rock-crushing behemoths

have carved a path
in the earth itself...

...redefining what's possible
with every hammer blow.

On the rugged Nevada
landscape, rock crawlers...

...machines that
look like cars...

but climb like mountain goats,

unleash their raw power,

taking death-defying tumbles...

...crawling their way up
90-degree rock walls

and down heart-stopping drops,

as they push the limits of
mechanical engineering.

Yeah, baby.

A rock crawler is a
specialized four-wheel drive

off-road vehicle built to slowly

and very methodically tackle
the most challenging terrain,

climbing boulders,
steep crevasses,

or taking stomach-churning
dives with ease.

Unlike race cars, where
everything on the machine

is built for speed, rock
crawlers are all about control.

These are precision vehicles
built to maximize flexibility,

torque and grip.

Speed is our enemy
and control is our friend.

Sometimes,
slow is scarier than fast.

Once a year,
the best of the best

travel from across
North America to transform

these rocky Nevada hills

into a pro, unlimited rock
crawler battleground...

...to take home
a small cash prize

and the all-important
bragging rights.

We are the top of the pro class,
and we're running

the biggest obstacles possible.

One of the things
that appeals to me

about this sport, rock crawling,
is the adrenaline rush.

I've been over
153 miles an hour on skis.

I've jumped out of a plane.

I don't think there was as
much adrenaline rush there

as there is actually
in driving these cars.

Rock crawlers
are the king of the hill.

You come out to
one of these events

and you will see
these teams do the impossible

with these vehicles.

The courses are tight.
It's a game of inches.

Precision driving
requires precision tools,

and the most critical tools

in the rock crawler's
kit are its tires.

These are the hands and
feet of the rock crawler.

This is what has to
reach out and grab that rock,

wrap around the rock,
pull you up the rock,

or hold you from
dropping off a cliff.

DR. EL-SAYEGH:
Rock crawling demands grip.

These machines are navigating

depth-defying angles

that no other vehicle
could even attempt.

They need tires made
from a special compound.

The rubber has to be
extremely soft,

allowing the tires to bend

and stretch with the
jagged rock surface.

This is a competition compound,

so it's a softer
durometer rubber

than what you typically
have on your car.

You can't actually
flex the rubber

on your passenger car tire;
you can flex this one,

and what that does is it
really helps grab the rocks.

It's not only the rubber that
makes these tires super grippy;

it also comes down
to the tire pressure.

Just like the tires on your car,

the crawler's tires need
pressure to hold their shape,

roll, and absorb
any bumps in the road.

The PSI -
or pounds per square inch -

is just a fancy way
of saying how hard

the air is pushing against
the rubber of the tire.

For an average car,
tires run at about 35 psi.

The crawler's tires
are dropped down to six psi.

That's pillowy soft,
so they can hug the rock.

If the tire is
inflated too much,

you're basically
just gonna spin on that rock.

I've got enough
pressure in the tire

that it's still
holding the car up

and low enough pressure
that it's wrapping around

and grabbing that rock.

When the rocks bite back,

these tires decide if they'll
continue the climb to glory

or slide to defeat.

Tire placement is key.

And one wrong step,

either a penalty
or you're done for the weekend.

For these tires
to do their important part,

they need heavy-duty support.

Trying to stop a
one-tonne vehicle on a dime

is a challenge.

But when that dime is
on the edge of a cliff,

it also needs
a mighty brake system.

This vehicle is equipped

with your
traditional braking system...

Yeah, baby.

...but it also has what we call
cutting brakes in our sport.

This allows me to control
the brakes independently,

from corner to corner.

Most modern cars have
four-wheel disc brakes

for maximum stopping power.
When you step on the brake,

the pedal makes every
wheel stop at the same time.

But cutting brakes
are totally different.

The cutting brake system
lets the driver control

each wheel's
brake independently.

By locking just one wheel,
the other three

can keep pushing forward,
allowing the crawler

to spin around that point.

It's the same move
an NBA point guard uses

when pivoting on the court.

Two massive levers
control the cutting brakes.

There's one for
each side of the rock crawler.

The levers are really
easy to manipulate.

Push them forward to
control the front wheels.

Beautiful, beautiful.

Or pull them back to
control the back ones.

Use them one at a time
or in combinations.

Beautiful, yep,
just like that.

Yeah, baby.

The result is a tremendously
tight turning radius

that can be created
around any tire.

And if the rock crawler does
get stuck in a tight position,

you could lock two
or even three tires,

depending on the situation.

The power to lock
individual wheels at will

helps the drivers stay safe

while making
split-second decisions

about the direction
they're traveling.

The braking
capacity is phenomenal.

You get on rocks and you're
in a precarious position

and, you know,

you're teetering on whether or
not you're going to roll over

or actually make the obstacle,

and when you actually
make that obstacle,

it's such a rush.

With all the complexity

involved in the braking system,

the drivers need to depend

on the car's three-speed
automatic transmission.

An automatic
transmission is vital.

The driver can't be wasting time
and energy shifting gears

with everything else
that's happening.

They're busy with brakes,
systems, and steering.

Managing the gears by hand
would be too difficult

and ultimately costly,

especially if
they make mistakes.

In the wild
world of rock crawling,

things can go sideways
in a heartbeat.

Falling down
is one hazard of many -

engine fires
and machine failures,

drivers get pinched,
trapped, or knocked out,

and there's the constant
risk of violent rollovers.

The danger is real.

The driver needs to be
kept safe in the vehicle.

And so, you've got
all these gussets

and braces that
are providing safety.

There's bars in
the door that, you know,

keep rocks from coming in.

In our sport,
safety is primary concern.

It starts with our fire suit.

We have a five-point
racing harness,

so I buckle that up, cinch it
tight, it locks me into my seat.

Rock crawlers are way
more rough and tumble

than your average
off-road vehicle.

Safety gear is a must.

Window nets keep
arms inside vehicles,

helmets mitigate
head and neck injuries,

and easily accessible
fire extinguishers

are within grasp when needed.

Rocks make for a harsh landing.

So, these rigs are
built to take a beating.

They stand on the
shoulders of fighting giants,

the 4x4 heroes of World War II.

Popularized by soldiers

and civilians after the war,

the love of these rugged
vehicles led to off-road clubs

and the eventual development
of the rock crawling sport.

The sport of rock
crawling was just people

pushing the limits of those
vehicles,

and they
kept getting stripped down,

the Jeeps kept getting
body panels cut off of them.

What started with factory models

quickly evolved into
customized machines

in pursuit of conquering
bigger and scarier obstacles.

Less weight reduced

the stress on the engine and
gave them more manoeuvrability.

Every pound saved was
a little bit more performance.

This thing's designed to go over
on top and back onto its wheels

and still be able to drive.

But drivers have
to be prepared for everything

because epic accidents
are inevitable.

When I first built this car,

I rolled this vehicle off
of a 25-foot cliff,

rolled multiple times,

but because of all
of my safety gear,

I didn't break any bones,

I was completely safe.

Disaster lurks
around every boulder.

Drivers need a second set
of eyes on the ground

to help them crawl
to the finish line.

Beautiful.

Mind the rear.

Yep, there you go.

Start curling a little
on the front now.

Go ahead.
Don't get crazy.

He's telling me how close
we are to obstacles...

Hey, go driver front.
Go driver front.

...whether or not I need him to
help me with extra traction...

I got you. Come on.

Work the rear. Go.

Yep.

...how much time we have left.

Two and a half minutes.
We got it.

He works really hard.

I'll tell you when.
Keep coming. Just keep coming.

He's depending on me, and I'm
depending on him out there.

Spotting is not for
the faint of heart.

These daredevils stand within
feet of these monster machines,

leaping from rock to rock,
risking trips or falls,

as they dodge and chase
the rig around the course.

Any distraction,
any slip could be fatal

and not just for the driver.

In Cedar City, Utah,
we were competing,

it was a little pop over,
much like this,

where I positioned myself,

I didn't think the car
was going to do anything.

And then, right as
John came over the ledge,

it hit and it rocked
the car over and hit me.

It basically folded me in half

and I went back and
I landed right on my head.

If I hadn't been
wearing a helmet,

it would have killed me.
It was bad. It was bad.

We're trusting each other
with each other's,

basically, lives sometimes.

It's truly a driver-spotter.

It's not just a one man show.
It's a team out there.

Getting behind the wheel

of a Pro Unlimited
rock crawler takes guts.

But don't be fooled,

these bodies are built tough,

ready to take some huge tumbles
and keep on kicking.

This is all steel structure,

and it's inch and a half
diameter 120 wall tubing.

It's as strong as it needs to be

to keep the driver safe
and make the car function.

The key to the
rock crawler's strength

is the humble triangle.

Triangles are
exceptionally strong

because of their ability to
spread force across their shape.

When a triangle does get hit,

that force is
dispersed along its sides.

That's perfect
for a rock crawler.

It takes such a beating
while it's running the course.

Basically,
the more triangles we have,

the stronger the design is.

So, when the rock crawler rolls
over or falls backwards,

the frame can absorb
the force of that impact.

You know, you want it
to take the impact

and still be safe.

You're basically
inside a full roll cage.

While the triangle

keeps these machines
in one piece,

it's their specialized
suspension that steals the show.

This is how rock crawlers

prove they're the
ultimate terrain masters.

These machines handle
all those hard knocks

thanks to the unique
structure of the suspension.

Inside each shock cylinder,

oil and nitrogen gas

are separated by
a free-floating piston.

The oil helps absorb impact
and dissipate heat,

providing a smoother ride.

As the shaft moves
into the cylinder,

reducing the length
of the shock,

the nitrogen is compressed,

supporting the
rock crawler's weight.

When the suspension flexes,

the shaft travels in
and out of the shock body,

changing the pressure
of the nitrogen as needed.

The crawler has
incredible travel,

which is basically
the maximum distance

that the front
or rear suspension

can compress to absorb impact.

More travel allows
the suspension

to better handle
bumps and twists,

preventing the crawler
from bottoming out.

Travel is the maximum
expansion or lift

you can get out of the shock.

And with up to
a foot-and-a-half of lift,

this rock crawler
can absorb a lot.

The suspension travel
on these is incredible.

These shocks are a 16-inch
travel shock on the front,

an 18-inch travel
shock on the rear.

By the time you bring one
up a couple inches

and bring the other one
down 16 inches, boy,

these things are completely
flexed sideways to one another.

You can suck
the suspension down,

so you can keep
a low centre of gravity.

You can also loosen it, so you
can get extension on one side,

allowing the tires to grab the
rock at some really wild angles.

Like you see right here,

the rear shock is
completely compressed,

so it can't go up any farther.
And if we come over and see

the other shock on the driver's
side, it's completely extended.

When I'm in this position,

I want the car to be
as stable as possible.

So, if you're looking
at the chassis right now,

this chassis is almost
completely flat to gravity.

So, this car
is extremely stable.

It may look crazy, but I'm in
complete control of this car.

Rock crawlers are
evolution on wheels -

part beast, part machine,

and an engineering marvel
from front to back.

Well, this is our passion.

When it all hits,

when you are on the right line,
when you're on the right rock,

and when that thing
wraps around it,

and it just pulls you
right up the obstacle,

it all feels perfect.
It's like hitting a home run.

In the desolate
foothills of Nevada,

these monsters of rock
use the latest science

to challenge
the laws of gravity.

Under the weight
of heavy freight,

in what seems like an endless
stream of passenger trains,

Sweden's 15,000 kilometres
of railway lines

take a daily beating.

All that action has
an impact at track level.

That's where you'll
find Sweden's

rolling railway repair fleet.

They are the biggest,
the most powerful ones.

I would say they are

the mightiest ones
that can be built.

These machines
suck up the bad...

...mix in the new...

...and then shake, rattle,
and roll the material...

...remaking the railway bed.

Whether carrying
freight or people,

trains are heavy and put
constant pressure on the tracks.

And traveling along these tracks
over and over causes wear,

deformation,
and movement of the rails.

If the foundation of the rails

isn't properly maintained
on a regular schedule,

it can be disastrous.

It all starts
with the RailVac...

...a giant vacuum
that sucks up rock...

...also known as ballast, the
foundation of a railway bed.

But when ballast rocks wear out,
they've got to be replaced.

When the ballast
starting to get like this,

then it's really, really bad.

You see, this is not correct.

This is very bad.
It's like dirt inside here.

Ballast is usually made of
crushed granite and limestone.

They help absorb the shocks
and keep the track dry

and the train running smoothly.

Good ballast is
larger rock with rough ridges,

allowing the material to
connect together more tightly,

which makes it more
stable on the tracks.

Bad ballast is
smaller, smoother,

and unstable because it
separates too easily.

Every time a train
rushes over the tracks,

the ballast beneath
gets more and more worn.

The longer it's used,

the rounder and
smoother it will become.

Eventually, the ballast
will be so worn,

it can't hold the
position of the tracks

or the weight of
the trains anymore.

Bad ballast
leads to unstable rails...

...and that could
spell disaster,

potentially shutting down
a line for repairs, or worse,

causing a derailment.

It's hard to imagine
a more specialized

rock guzzling machine.

The RailVac is the
length of a Boeing 737,

and it devours
everything in its path.

It's got more power than a lot
of vacuum cleaners together.

So, it's definitely
one of a kind machine.

The purpose of the
RailVac is to vacuum.

It sucks up all the old ballast,

the soil, the mud, any debris,

cleaning up the tracks
to get them ready

for fresh new material
to be laid down.

There's a flexible nozzle

at the end of the suction arm
that can snake under rail ties

to clean up years of buildup.

It's much more versatile

and a lot less
disruptive and safer

than using something like an
excavator or doing it by hand.

Think self-propelled shop vac.

Then, supersize it, delivering
a rock-sucking 700 horsepower.

It's a lot of power.

You don't want to get
your hands in the nozzle,

for sure, I can tell you that.

You don't want to get
your hands in the nozzle,

When Sweden needs
to remake its rail beds,

it rolls out the RailVac to
remove railway ballast

at an incredible rate -
40 cubic meters per hour.

Like a tornado
inside a container

that causes the air to
flow through the machine,

sucking up the ballast
and all the bad materials.

There's no human
driver aboard this machine.

Instead, the human
walks beside it,

controlling its
operation via joystick.

But rather than
watching over video,

the operator can see
the work in real life.

Like operating a big RC car
or something like that.

So, it's pretty cool.

Its belly
now bulging with ballast,

this beast needs
to unleash its load.

So, it travels down the track,
and with the touch of a button,

a hydraulic sigh
of relief can be heard.

Side hatches on the tank open up

and the old ballast
tumbles out into the ditch.

We emptied out both sides,

about 40 cubic meters
of dirt ballast.

The RailVac moves up the track

to continue slurping
bad ballast.

The next machine in the railway
restoration is arriving.

True to its name,

the ballast feeder is
loaded with fresh rocks,

ready to drop them in place.

The suction machine
and the ballast feeder

are not more than 5-10 meters
away from each other.

To be able to be that
close, with safety,

the skilledness and the trust

between the operators
is very important.

The ballast feeder
uses a conveyor belt system

that's surprisingly agile.

It can rotate effortlessly
from side to side,

strategically placing ballast

exactly where it's needed
along the tracks.

The whole floor will move

and this conveyor belt is
going to drive it forward,

so we can throw stones.

The other machines,
they can only, like,

throw stones straight forward.

We can throw
stones 180 degrees.

That's the unique part of
this ballast feeder machine.

The ballast feeder
is fully automated,

and the operator can control

the flow of the ballast
from the touch screen,

saving a lot of time.

There are train
schedules to keep,

and delays on the line can
cost millions of dollars.

Putting the ballast
exactly where it needs to go

is a huge factor in keeping
this operation tight.

The ballast feeder leads

a specialized
train of its own.

I'm coupling
together the machine,

and we're going to synchronize
it with those cables,

so they can work together.

Today's
rock-slinging configuration

comes with four wagons.

Altogether, it's 90 meters

of rock and roll
ballast feeding action.

This is the four wagons then

because this job
will require all that stone.

Out with the old,
in with the new.

Upkeep like this is critical in
keeping the railway on track.

Railways, as we know them,
have existed since the 1700s.

These tracks were laid on the
ground or on wooden roadbeds

and were prone to instability.

As trains became heavier
and faster, the instability

and shifting of the
track laid on the ground

becomes a huge
problem with time,

and ballast is the solution.

By the 1800s, railway
builders began using beds

of crushed stone or gravel
to support the track

and provide stability.

The change of ballast in early
days was done by a shovel

and bucket.

Then, you have to stop
the traffic for a long time.

As trains evolved,

so did the technology
to support them.

Manual labour was
replaced by machines

specially designed
for the task.

Once the ballast is laid

and the dust is settled,

a third machine comes
along to shake things up.

The tamping machine
may look unsettling,

but in fact, it's designed
to do the opposite.

16 prongs, or tines,

plunge into the
rail bed and then vibrate.

The action forces
the ballast to fit more snugly.

Up close, this machine looks
more like a transformer

than a maintenance vehicle, with
its spider-like tamping unit.

The operator
is constantly monitoring

the plunging prongs.

This 83-tonne behemoth

can tamp 700 meters
of rail bed an hour.

When everything is
good to go and all my...

measurements
in there looks good,

we start to tamp,
and we go up to first

sleeper here, and its rollers

that grab the railroad
in each and lift it up

and hold it exactly right.

Now,
the vibrating tamping tines

plunge deep into the ballast.

The tines squeeze together,

vibrating and
shaking the ballast rocks

and allowing them to settle,

creating support
for the rail lines above.

A few more squeezes for
good measure ensure the voids

are completely filled
with the fresh ballast.

The whole process is repeated

until the tamping
machine registers

the correct ballast pressure
levels beneath the rail.

They do it two or three times

when we have this much to lift,

and then,
the ballast gets stiffer,

it holds up better.

Once the ballast
is all tamped down,

the tamper corrects
the rail alignment

to make them perfectly
parallel and level.

The rails are then laid
carefully over the new ballast

to ensure the
trains run smoothly.

You're responsible

for the track when
it's finished,

so I try to make it perfect.

If it's like this now,
it's perfect.

This is how you want it to be.

All new ballast,

this is gonna
hold many years forward

and gonna be more stable
during winter,

during rain season, all that.

This stretch
of track is refreshed,

but there is
a lot more railway ahead

for these
specialized machines.

It went pretty well.

We all planned to
do 45 meters and we did it.

So, yeah,
job well done, I would say.

And they're keeping
Swedish Rail on track,

one kilometre at a time.