All language subtitles for Impossible Engineering s02e07 US Navys Super Submarine.eng

Today
on "Impossible engineering"...

The Virginia class,

one of the most
advanced submarines ever built.

To come down the waterfront,

to see these submarines
being built,

it is truly a magical thing.

Pushing marine
engineering to its limits.

The Virginia class
is acoustically

the stealthiest submarine that
the U.S. Navy has ever produced.

It took revolutionary
engineering...

What we have now on Colorado

really incorporates
the latest and greatest

of what's out in industry.

To make the impossible possible.

Submarines are an invaluable
asset to the U.S. military.

After decades of service,

their fleet
is in need of an upgrade.

The Navy
was looking to a replacement

for the 688 class ships.

They were nearing the end
of their useful life.

Similar to a vehicle,
it gets wear and tear over time,

and it was time to come up
with the newer model.

What designers came up with

is breaking the boundaries
of maritime engineering.

What we're looking at

is the 15th Virginia class
submarine,

the U.S.S. Colorado.

She's 377 feet long.

She can dive to depths
greater than 800 feet.

She can operate at speeds
greater than 25 knots.

The Virginia class
is one of the most advanced

nuclear-powered fast-attack
submarines ever produced

for the U.S. Navy.

At the electric boat shipyard
in Groton, Connecticut,

a 15th Virginia class vessel
is under construction.

Starting with
the first ship of the class,

it took 15-million hours
to build that ship.

And with the Colorado,

we brought that cost down
to 10-million hours.

That's the kind of effort
that's required

to put one of these remarkable
ships to sea.

I've served on three classes
of submarines,

and by far, the Virginia class
is the best-engineered

that I have had the pleasure
of serving on.

These technological
titans are as long as 26 cars.

Each sub weighs 7,800 tons.

That's 40 blue whales.

They're equipped
with an advanced nuclear reactor

and can dive to depths
of almost 800 feet

or inch across shallow water
with pinpoint accuracy,

thanks to a control room

that's equipped with
an automated navigation system.

The pilot can literally dial in

any depth, any speed.

It allows the ship to operate

in much shallower water
close to shore.

The combination of stealth,
endurance, versatility,

the range is truly a benchmark
for all ships.

The engineers
of the Virginia class sub

have created a modern marvel,

one that would have
been impossible

had it not been for the great
innovators of the past.

Humans have been diving
to the depths

of our oceans for centuries.

Hmm?

Hello!

Ancient sponge divers
used to plummet to the sea floor

using heavy rocks.

They held their breath
for minutes on end

to retrieve precious bounty.

In the 5th century B.C.,

Greek diver Scyllis
breathed underwater

using a hollow reed...

Hmm?

Allowing him to sabotage
the enemy Persian fleet.

Legend has
it Alexander the great

used the first
submersible craft.

He dove into
the Bosporus straits

using a clear glass barrel
to spy on enemy sea defenses.

Controlling a vessel underwater
was nearly impossible

thousands of years ago.

And today,
it's still a huge challenge.

At the David Taylor model basin
facility in Maryland,

nautical designers are testing
their submersible designs

at the annual international
submarine races.

Scores of young engineers
from around the world

have brought submarines
that they've designed and built

with the goal of becoming the
fastest human-powered submarine.

The challenge is go 100 yards

without coming out of the water,
touching the bottom,

touching the sides, or any part
of the submarine falling off.

100 yards
may not seem like much,

but controlling a submersible's
buoyancy is no easy feat.

So up and down
is a little bit difficult.

Left and right so far
has been really good.

I can follow the line.

It's just been a question
of keeping the buoyancy right.

Did we make it further
than before?

We've got about...
Yeah, sort of halfway.

The trim is slightly off.

Like, the controls
seem to be working.

The propeller's definitely
working.

The key to the perfect
submersible continues to elude

even the finest
young engineering minds.

But they're getting close,

thanks to an invention created
almost 250 years ago

by David Bushnell.

Dr. Rhys Morgan is at
the royal Navy submarine museum

Ginosport, England,

uncovering information
about a secret weapon

from the revolutionary war.

And this is it... the Turtle...

The first submersible used
in recorded underwater combat.

Bushnell's plan for the Turtle

was to sneak up on
the British enemy ships

moored in New York harbor.

The vessel had lots
of weights in it

to help it sink into the water,

and underneath the base,
there was a ballast tank,

which would be filled
with water.

And the operator,
a man called Ezra Lee,

would pump the water
in and out of the tank

to help sink to the right depth.

As the Turtle slips underwater,

its two surface-mounted
snorkels seal.

The pilot powers the craft

using a hand-cranked
front-mounted propeller.

As he approaches his target,
he readies the Turtle's weapon.

The Turtle's weapon,
a keg of gunpowder,

was attached to the back
of the wooden hull.

As the submarine silently
crept up underwater

to the base of the ships,

it would be attached
by this drill,

which would be literally
hand-drilled

into the base of the ship.

Unfortunately for the pilot,
Ezra Lee,

the British fleet
had metal hulls.

By sheer bad luck,

Ezra Lee wasn't able
to drill into the ship's hull,

so the Turtle was a bit
of a failure.

But having said that,

it did set the precedent
for submersible combat,

and the principles
of ballast tanks and propulsion

still to this day
remain on all submarines.

The Turtle
can only hold one person.

The U.S. Navy's Virginia class
can hold 135 people.

Ships manager Patty McDaniel

is charged with fitting out
the 15th Virginia class sub.

One of the challenges
with the design

of the Virginia class ships

is all of the services
and equipment

that we need to fit
into a tight space.

So all through construction,
we tried to design having spaces

to put all
of the services up in.

One of the other challenges
with that is the crew,

when they come out to sea,

these racks are the extent

of the space many
of the crew members

have to store
all of their items.

So just this thickness deep
is what these sailors have

to have all of their clothing
and books

and whatever they choose
to take out to sea with them.

Tight quarters are
a recurring theme on board,

regardless of rank.

This is the wardroom
of the Virginia class submarine.

So the wardroom,
as you might imagine,

is where the officers gather
to eat, among other things.

It's also where a lot
of the meetings happen

to discuss all of the ongoings
on board the ship.

Interestingly, too,

submarines are very limited
on space.

So the table is a large,
clear surface.

So this doubles, out at sea,

as if you needed to have
an operating table.

Not only can the Virginia class

accommodate more people than the
17th-century turtle submersible,

it can also dive much deeper.

They can reach depths
of about 800 feet,

thanks to a system of internal
and external ballast tanks.

We have five external
ballast tanks

that are normally
filled with air

when I'm riding on the surface.

When it is time for us to dive,

we'll open vents
on those ballast tanks.

There's grates on the bottom
of the ship

that allow water to come in,
displace the air,

making the ship

just slightly negatively
buoyant.

We then proceed down
to the depth

that we want to go to,

and we use
internal ballast tanks

to make the ship
neutrally buoyant

that then we can progress
on our way

whatever depth we choose.

The crew on board
the Virginia class

have an abundance
of cutting-edge controls

at the firingertips,

one of which is replacing
the most iconic feature

in submarine history.

The $2.7-billion
Virginia class submarine

is the U.S. Navy's most advanced
attack sub.

The 15th vessel of the class
is currently under construction

at Groton, Connecticut.

Ships manager Patty McDaniel

is in no doubt about
its engineering pedigree.

What we have now on Colorado
really incorporates the latest

and greatest of what's out
in industry.

We're always improving,
we're always getting better,

and we'll continue to evolve.

The crew on aboard
the Virginia class

have an abundance
of cutting-edge controls

at their fingertips,

one of which is replacing
the most iconic feature

in submarine history.

The periscope has been
a key component on the submarine

for over 100 years,

but engineers
on the Virginia class

are taking a bold step
toward the future

by replacing the periscope

with a state-of-the-art
photonic mast.

The photonic system is a mast

with a sophisticated
camera system

that allows what would normally
be displayed just in a periscope

to displayed on wide-screen
monitors throughout the ship.

I used to have to have

an optical periscope
that came down,

which drove the construction
of the submarine

and the orientation of all
of the rooms on the submarine.

Bulky periscopes force
most submarine control rooms

to be located
on a cramped upper deck.

On the Virginia class,

the compact imaging equipment

is housed in a part of
the submarine known as the sail.

This allows the sub's
control room

to be built
on the wider second deck.

My control room
that I'm standing in right now

houses all of
the important decision makers.

It really brings the crew
together to operate as a team,

as a unit.

I really believe
the Virginia class submarine

has set a benchmark
for marine engineering.

The designing and building
of the Virginia class

was a continuation of all
the great work we've done

for over a century.

It's not just
the photonic system

that makes the Virginia class
revolutionary.

A virtually silent propeller,
known as a propulsor,

drives the nearly 400-foot
submarine

and a sophisticated system
of sonar arrays

allows it to map its way

across the ocean floor.

The ability to
put literally tens of thousands

of horsepower into
the main engines,

into the propeller,
and yet be so quiet...

The level of technology
required to do that is amazing.

War shield here.
0-5-4 rate, almost 10 yards.

The Virginia class
is acoustically

the stealthiest submarine that
the U.S. Navy has ever produced.

The Virginia class
is virtually undetectable

as it travels through
the world's oceans.

But how do you construct
the perfect hull...

One that's optimized
for sub-surface speed

and maneuverability?

It's a task that would be
impossible without help

from some of history's greatest
naval engineers.

During world war ii, submarines
were essentially surface ships

that could submerge themselves
for up to 48 hours.

Underwater, the vessels
were cumbersome and inefficient.

Improving performance
meant a total redesign.

Naval engineering professor
Matt Werner

has come to the Webb institute
of naval technology

to see firsthand
what post-world war ii engineers

came up with.

So here we have
our world war ii submarine,

and if we compare it
to this model of a surface ship,

we see a great number
of similarities.

This hull form is really
about traveling on the surface.

Its sleek design creates

an extremely low bow wave,

resulting in a small wake
and low resistance.

Perfect for minimizing drag
on top of the water.

When we take this same hull form
and place it below the water,

we pay a penalty
for this type of hull shape.

Surface-mounted equipment
and an uneven hull shape

create two types of drag...

Frictional drag
between hull and water

and form drag as water
separates from the hull.

This leads
to resistance-inducing Eddies,

which dramatically reduce speed.

Admiral Charles Momsen
was determined to come up with

a more efficient design.

The U.S. naval officer

commissioned
over 25 large-scaled models.

Those models ultimately resulted
in the teardrop hull form

that became the standard
for all modern submarines.

To appreciate this
game-changing design in motion,

Matt analyzes
the hydrodynamic qualities

by injecting dye into the tank.

So, we've got the model
in the water now.

We're towing it
below the surface.

We put dye in front of it,

and the model will pass
through that dye field,

and hopefully,
what we'll be able to see

is a nice, smooth flow
across the stern of the moDel

as it passes by,
so let's see how it goes.

It's coming into the window now
and right into the dye field.

And the bow goes through
the dye.

Wow, look at it!

Look how smooth
the flow is off the stern

as it passes through
that dye field.

That's showing me
we have very low resistance.

The hull's teardrop shape

dramatically reduces
both frictional and form drag.

So after countless
hours, tests, and calculations,

admiral Momsen and his team
had done it,

and this is three sult...
The U.S.S. Albacore.

The albacore changed
the face of submarine design.

By getting away
from that ship-type hull form

and going to a true
submerged-type hull form,

we have the fastest thing
in the water,

the most maneuverable sub ever
to that point,

and the baseline
for all subs to come.

It's been 60 years

since the albacore
first set sail,

and the U.S. Navy's latest
and greatest submarine,

the Virginia class,

is using admiral Momsen's
game-changing teardrop hull.

We have very strict
circularity requirements

to ensure the hull sections
are very circular.

And when we join them together
to form the pressure hull,

it must be extremely straight
so that our travel

through the water uses
the minimum amount of energy.

And this manufacturing center
is where it all comes together.

We have
3,600 dedicated men and women

who take raw steel plate, pipe,
and cable

and create completed
2,000-ton modules.

The U.S. Navy's Virginia class

is pushing the boundaries
of submarine design.

Program vice president
Ken Blomstedt

has been at the heart
of its engineering since 1996.

When I saw
the original requirements

for the Virginia class,

there were several requirements

that I thought were
pretty challenging.

But as we started to build
the ship,

it really came together

and turned into just
a great platform.

Each submarine is made
up of four super-sized modules

that, when combined,
measure almost 400 feet.

The vessel contains
around one-million components

and requires
10-million man-hours to build.

We have
3,600 dedicated men and women,

who take raw steel plate, pipe,
ancad ble

and create completed
2,000-ton modules.

Raw steel plate is brought in.

The cut machines
automatically cut the plate

to the right dimensions.

In the case
of pressure hull structure,

it's rolled to get that circular
shape for the pressure hull.

It takes 5,000 tons
of force to form the steel

into the iconic submarine shape.

Engineers take a sideways
approach to assembly.

Hull cylinders
are turned axis vertical

and outfitted with structural
shapes like internal tanks

and large piping assemblies.

It allows us to use cranes
and vertical picks

to drop those assemblies in

and more cost-efficiently
install them.

Next, each cylinder
is placed horizontally

so the decks can be slid in.

The completed modules are then
shipped off for final assembly.

When you pair up
the last hull section,

and you actually have
the ship look like

a whole ship together in a bay,

it's really exciting
to see it all come together.

Transporting
this monumental structure

to its natural habitat
is an impressive sight to see.

We actually have
78 of these transfer cars

moving in unison.

It's one individual
flipping one switch,

and all of the cars
start moving together.

And it drives the whole ship
out along the tracks

on the floor right
onto the pontoon,

and we float off.

It's really been amazing

seeing these systems that
I did the calculations on

be built and tested

and then actually eventually
go out on sea trials.

It's really a privilege

to be able to see it all
come together.

For the Virginia class to be
successful in its wide variety

of surveillance
and reconnaissance missions,

it must be able
to stay underwater

for long periods of time.

This crew of 135 sailors

have to be able to go anywhere
in the world,

deploy from their home port,

and be operating in any ocean

and not be concerned about
the amount of fuel consumption

that they are using.

So how do you propel a submarine
to the most remote parts

of the globe without refueling?

It would be impossible

without help from the innovators
of the past.

The Virginia class
is the U.S. Navy's latest

and greatest submarine.

But for it to be successful
on its many missions,

it must be able
to stay underwater

for long periods of time
without refueling,

a task that would be impossible

without help from the innovators
of the past.

Early submersibles
relied entirely

on human power for propulsion.

Accounts from 1620 show that
Dutch engineer Cornelis Drebbel

submerged a fully crewed vessel
into the river Thames

and then rowed it
from Westminster to Greenwich.

And stroke.
And stroke.

But historians now believe
a semi-submerged tidal drift

may be a more accurate
version of events.

Useless!

In 1863, the first mechanical
submarine was launched.

The Plongeur
ran on compressed air

and had an impressive top speed
of 4 knots.

Ooh, la, la!

But the ship had to be
incredibly long

to fit its 23 air tanks.

It also needed a support ship.

Ow! Watch it!

Cracking the submarine
propulsion code

came down to one colossal
scientific discovery.

Dr. Rhys Morgan is at
a secret decommissioned location

in Austria to find out more.

This is a nuclear reactor...

The core of a nuclear power
plant.

The core itself is a whopping
20 meters deep.

If up and running,

this reactor alone would
produce enough electricity

for 1.8-million homes.

This is an incredible moment.

What an amazing feat
of engineering.

The world's first
peacetime use of nuclear power

occurred when
the U.S. government switched on

the experimental breeder reactor
in Idaho in 1951.

It temporarily powered the town
of Arco,

paving the way
for domestic nuclear power.

But captain Hyman Rickover
of the United States Navy

had other ideas.

He saw the potential

for using this technology
in a submarine.

Rickover was
an incredible pioneer.

The problem with powering
submarines is that most forms

of power for propulsion
require air,

so the submarines
had to resurface,

or the alternative
would be battery,

but they just didn't last.

Rickover was convinced

that the fundamental process
of a nuclear reaction

to boil water and create steam
could be a source of power.

Nuclear reactors are just very
large ways of boiling water.

And here I've got
a steam cleaner

that's going to represent
my nuclear reactor.

I've got some water,
and when I pull the trigger,

it boils the water,
turning it into steam.

As I direct the steam
towards my turbine...

It starts
to generate electricity,

and that turns on my light.

The difference
between my little reactor here

and this enormous one here

is in the way
that the water is heated.

And the answer lies at the very
heart of the core itself.

Nuclear fuel rods contain
thousands of uranium pellets,

and it's the uranium atoms
that split,

causing a chain reaction

that generates vast amounts
of energy in the form of heat.

The result
is an almost limitless supply

of power that can keep
on producing for years.

The problem Rickover faced
was scaling down something

as huge as a nuclear reactor

down to the size of something
that could fit into a submarine

and still provide the power.

What Rickover came up with

was the world's first
pressurized water reactor.

The core
inside his reactor vessel

heats a loop
of pressurized water.

This in turn vaporizes water
in a secondary loop,

creating steam to drive
the main turbine,

which produces electricity.

After vigorous testing in 1954,
the nautilus was launched.

This pioneering nuclear vessel
traveled 1,300 miles

in less than 90 hours
fully submerged.

This was a huge game changer
in submarine engineering.

Previously, submarines
could only stay underwater

for up to 48 hours.

Now there was absolutely no need
to resurface.

Rickover
and his incredible engineers

had made the impossible
possible.

Captain Rickover's
nautilus reactor

needs to be refueled
every two years.

The designers
of the Virginia class submarine

are taking this technology
to an unprecedented level.

The Virginia class submarine
has a life-of-ship core.

It never needs to be refueled.

Previous submarines had
to be refueled during its life.

The Virginia class submarine
is powered by a nuclear reactor

that has been designed
to last the life of the ship

for all 33 years.

Converting seawater to steam,

this top-secret reactor plant

is capable
of powering the vessel

for nearly one-million miles
without refueling.

The ship
has amazing capabilities.

In fact, the only limiting
factor for me when I go to sea

is the amount of food
that I can bring onboard.

The nuclear power
provides us the ability

to operate anywhere in the world
in any ocean environment.

Its unlimited power source
also allows the vessel

to hover motionless in one
location for weeks at a time.

The reactor
on the Virginia class

is the most advanced reactor
that the U.S. Navy has produced.

But sustaining a crew
underwater for months at a time

is no easy feat.

We have to monitor
the atmosphere controls on board

and the levels of the oxygen
to make sure

that it remains habitable
for the sailors.

It's a challenge

that requires even more
impossible engineering.

For more than two decades,

an army of designers
and engineers

have been working
on the Virginia class,

one of the most sophisticated
submarine fleets

ever built for the U.S. Navy.

It is wonderful
to wake up every day,

to come to work.

Everyone takes a lot of pride
in what we do.

And it's a joy
to see it come together.

12 Virginia class subs
are in service,

each equipped with a
state-of-the-art nuclear reactor

that allows the vessels
to remain underwater

for months at a time.

But keeping the crew safe during
long-term sub-surface missions

is a huge challenge.

In the submarine,
we have an enclosed environment,

and so, clearly,
we have to monitor

the atmospheric controls
on board

and the levels of the oxygen,
the carbon dioxide,

and other trace gases
to make sure

that it remains habitable
for the sailors.

So how do you keep
over 100 crew members

happy and healthy for months
at a time underwater?

The answer lies with the work
of a genius chemist

from over 200 years ago.

To appreciate the challenges

behind creating a habitable
environment underwater,

Dr. Rhys Morgan is exploring
a naval test facility

in Portsmouth, England.

This is a hyperbaric trials unit
used by navies around the world

to test undersea
and high-pressure systems.

This hut can uniquely re-create

the kind of immense pressures
experienced by submarines

at the very bottoms
of the ocean.

Rhys is using
this technology to put himself

in the shoes of early submarine
passengers to experience

how quickly the atmosphere
on board can change.

This is a potentially dangerous
experiment,

so I'm here with Jules,
who's gonna look after me

inside the chamber.

Outside, there's
a whole team of medics

looking after both of us.

This is a completely sealed
unit now.

Rhys and his crew now replicate

the physically demanding work
on board a submarine.

It's amazing how you do
start to feel

slightly more out of breath
than if you were just outside

on a normal exercise bike.

Co2 makes up just 0.04%
of our normal atmosphere,

and in this quantity,
it's completely harmless.

But in a sealed unit,
the level builds as we exhale

and can become
dangerously toxic.

We're about five minutes in now,
and we've already created

half the maximum permissible
co2 levels in the chamber.

So we're really starting
to use up the oxygen.

Whoo! A bit hot.

Okay.

We're opening.

After nearly
six minutes in the chamber,

the oxygen and co2 levels
are completely unbalanced.

It's too dangerous
to remain inside.

Exhausted.

I don't know how those early
submariners did it.

I could really feel
the oxygen content lowering

and the carbon dioxide
increasing in there.

Submarine engineers
in world war ii

tackled high carbon dioxide
levels

using a chemical
scrubbing process.

They spread large quantities
of soda lime around the sub

to absorb the co2
in the atmosphere.

But by far,
the bigger challenge...

How do you replenish
oxygen levels

in a completely enclosed vessel?

The Virginia class submarine

is one of the most advanced
fast-attack submarines

ever produced for the U.S. Navy.

Its missions require it to be
underwater for months at a time.

How does the sub
replenish oxygen levels

without ever going
to the surface?

The answer comes from the early
1800s through the work

of English chemist
William Nicholson.

Inspired
by the electric battery,

Nicholson experimented with
placing battery leads in water.

The result
was a chemical reaction

now known as electrolysis.

This is a simple demonstration
of electrolysis.

I first have my water
for the electrolyzer.

Okay.

Two water-filled test tubes

are placed over the submerged
negative and positive electrodes

before the electrical current
is switched on.

And you can start to see
immediately the gas bubbles

forming on the electrodes here.

The negative electrode
is generating hydrogen.

And the positive
electrode is generating oxygen.

And so each of these jars

now has displaced
the water with the gas.

This reaction is caused

by the positive
and negative electrodes

attracting
and separating the oxygen

and hydrogen molecules
in the water.

Now what we're gonna do
is test the purity of the gas.

And this jar here
has got oxygen in.

And if I blow this splint out,

with the pure oxygen
inside, it should glow.

So there we have it.
We've produced,

in just a few seconds,

enough oxygen to fill
this test tube.

What we need to do
in a submarine is to scale up

this whole process to provide
enough oxygen

for all the submariners
deep beneath the waves.

The engineers
of the Virginia class

are using Nicholson's
groundbreaking work

to create life-sustaining
conditions underwater

for months on end.

In order to maintain
that environment

without coming up for more air,

we create oxygen
through electrolysis.

We have pure water.

We then use electricity to split
the hydrogen from the oxygen.

We distribute the oxygen
throughout the ship

and then remove the hydrogen

so that we can maintain levels
right at 20%,

just like normal air.

The U.S. Navy's advanced

integrated low-pressure
electrolyzer

can create over 200 cubic feet
of oxygen per hour.

Potentially toxic carbon dioxide

is removed by a sophisticated
amine-based removal plant.

You expel carbon dioxide,
and that builds up in the ship.

I have atmosphere-control
equipment onboard that absorbs

that carbon dioxide.

I then compress it

and can either store it
or discharge that, as well.

The crew on board
the Virginia class

will experience seemingly
normal living conditions,

but they'll be up to 800 feet
below the ocean,

so safety is a top priority.

Every possibility
must be prepared for.

In the unlikely event
of a submarine sinking,

we definitely have
the capability to escape.

In case a sub's internal
atmosphere is ever compromised,

Chief warrant officer
Eric Nabors

trains the crew to perform
a pressurized escape,

using an ingenious piece
of equipme

nt trains the crew to perform
a pressurized escape,

called a seie suit.

It's designed to provide
the occupant fresh breathing air

through the compression
and ascent phases.

It provides 75 pounds of
positive buoyancy in the water.

It travels
at 625 feet per minute

through the water column.

Topside, request permission
to fill and equalize.

You have permission
to fill and equalize.

As the regulated
lifting force of the suit

propels the students
safely through

the 37-foot escape trainer,

they must follow
one golden rule.

The number-one rule
of submarine escape is never,

ever hold your breath.

Because the escapee is breathing
compressed gas at depth,

when they travel through
the water column,

the pressure
around them decreases.

We are concerned with pulmonary
over-inflation syndrome.

This potentially fatal
condition can cause the rupture

of air sacs
in a crew member's lungs.

If a student
were to hold their breath,

that would occur, so we teach
them to breathe normally

or exhale the entire way
to the surface.

Are you okay?

I'm okay.

In open water,
the seie suit can withstand

up to 250 pounds of pressure
per square inch.

These suits have been tested

to depths up to 600 feet
of seawater.

The seie suit itself is an
incredible piece of engineering.

It's been more than a century

since the first
self-propelled submarines

plunged into the oceans.

Now, by drawing
from the innovators of the past,

adapting their ideas,
up-scaling them,

and making trail-blazing
discoveries of their own,

the engineers, designers,

and workers constructing
the Virginia class

are making history.

To come down the waterfront,

to see these submarines
being built,

to see the crew starting
to take over system by system

as we turn it over to them
and bring this ship to life,

it is truly a magical thing.

The Missouri just returned
from six months of operations,

and if you could imagine
driving your car

for six months straight,
24 hours a day,

it's truly a testament to
the engineers who designed it,

the people who built it,

and those 135 sailors
who operate and maintain it

on a day-to-day basis.

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