Original subtitles

Narrator: The war that defines a nation...

Hinges on a campaign waged at sea...

Captain: Fire!

Narrator: That transforms naval warfare forever.

James: The american civil war was not only the bloodiest conflict,

It was in many ways the first modern conflict.

Narrator: Secret weapons...

Shocking surprises and stories of raw courage,

All lost beneath the waves.

Crew: I think we might have a shipwreck...

James: We're on it.

Narrator: Imagine if we could empty the oceans...

Letting the water drain away

To reveal the secrets of the sea floor.

Now we can.

Using accurate data...

And astonishing technology to bring light once again

To a lost world.

How does this metal monster create a naval revolution?

Anna: It had to have been terrifying.

Imagine the horror.

Narrator: What does a mangled wreck reveal

About a top-secret arms race?

Michael: There are secrets still left to be discovered.

This was a legend.

Narrator: And at terrifying new weapon destroys one of the

Most powerful warships ever built.

(explosion).

(theme music plays).

Narrator: For four bloody years a nation tears itself

Apart in search of its destiny.

Anna: It was truly americans against americans.

Narrator: Between 1861 and 1865, the union and the confederacy

Are locked in combat across a 2,700 mile border.

But historians now understand that battles on land...

Tell only part of the story.

Craig: The war at sea dramatically affected the

Trajectory of the war.

Narrator: The naval conflict takes place on rivers, lakes

And all along the american coast.

Incredibly, over 2000 civil war wrecks survive.

And one of the most significant lies here

In the waters of virginia.

As the atlantic ocean drains away,

A broken battleship begins to emerge.

The result of a battle that sends shockwaves around the world.

Maritime archaeologist james delgado and historian

Anna gibson holloway are in hampton roads...

Searching for a body.

James: The fact that we are right at the spot.

Anna: It's an amazing scene.

James: Yes, this is a battlefield.

Narrator: They're in a stretch of water, that in March 1862

Is the most dangerous in america.

To the west lies the confederate capital, richmond.

To the north, the union capital, washington dc.

James: It's a critical point and so it is no surprise that

This is going to be the setting for the first great

Naval encounter of the american civil war.

Narrator: The confederates hold most of virginia.

But on the north side of hampton roads a lone union

Fortress is home to a squadron of warships.

One of them is the uss cumberland.

Sleek, fast and armed to the teeth.

When launched, 20 years earlier, she was the most

Powerful ship in the us navy.

But on the evening of March 8th astonishing reports

Reach the union base.

Eyewitnesses describe a strange vessel bearing down on the cumberland.

In minutes...

(cannon fire).

She disappears.

So, what sank her, and how?

Anna: They're going to be going right um, down the

Elizabeth river into the heart of hampton roads.

James: So, they're coming in right here and this where they hit.

Anna: It was such a scramble...

Narrator: James and anna's research is part of a

Comprehensive survey of the underwater landscape here.

But it's not easy.

James: This is very dark water, you've got a river

Coming down to meet the sea, its silty.

You really can't see your hand in front of your face.

Narrator: The team's multi beam sonar fires sound waves

To the sea floor...

Mapping the shape and size of anything on the sea bed in perfect 3-d detail.

Data from the scans begins to appear...

A ghostly outline.

Anna: Just amazing...

So, what are we seeing here?

James: Well we're right over the wreck now.

What we see are the timbers and the more or less intact

Hull of the cumberland.

Anna: So, we're looking at a war grave here.

James: Oh, very much so.

Narrator: To discover what happened here, we can combine

Data from the scans with powerful graphical software

And uncover one of the first naval casualties of the civil war.

An incredible scene emerges.

Corroded ironwork...

Then the twisted remains of a large wooden hull.

Anna: You can still see the outline, the form of cumberland.

James: Articulated wooden timbers, the sides of the ship.

You have this sense of this ship sitting down there,

Shrouded in mud.

Narrator: It's a haunting scene.

But does it contain clues?

There's cannon shot half buried in the mud,

Normal for a battle of this era.

But this isn't normal at all.

Debris spread over 350 feet.

Something much more destructive than cannonballs

Hits the cumberland.

Using contemporary accounts and evidence from the drained wreck,

We can bring an extraordinary moment back to life.

As the cumberland lies at anchor she is suddenly

Challenged by a ship unlike any other.

A ship with no sails, but driven by steam...

A ship covered not in wood, but metal.

The first ever american ironclad: The css virginia.

The confederate ship bristles with weaponry.

Six heavy cannon and four large rifled guns.

It's no surprise that witnesses imagined it;

A horrid creature of a nightmare.

(gunshots).

Craig: They manned the guns and began firing.

Shots would bounce off her side.

Anna: Imagine the horror.

The virginia comes extremely close to cumberland, so close

In fact that the men on board the cumberland recall that

They could hear the taunts and the laughter inside the virginia.

(laughter).

Narrator: Near immune to the cumberland's broadside,

Virginia drives straight at her wooden enemy.

Deploying a tactic more familiar to the roman empire

Than the 19th century.

A huge metal ram.

Her sheer power and momentum do the rest...

The impact is devastating and sends 121 men to their deaths.

Virginia immediately turns her guns onto another union

Warship and smashes it to pieces too.

Craig: It was the most decisive defeat of the union navy

Until pearl harbor so this was an absolute shock.

James: What happens here at that moment is that that type

Of ship is rendered obsolete.

The age of the wooden wall is over, all hail the age of iron.

Narrator: But the confederates aren't the only ones working

On a secret weapon.

The union navy has one too.

This, the uss monitor.

A different kind of ironclad.

The day after the death of cumberland, the two metal warships

Will meet in one of the civil war's defining moments.

As the waters off north carolina begin to drain away,

The wreck of one of these iron monsters

Begins to emerge from the depths.

Narrator: Cape hatteras.

Here off north carolina lies a legend of the civil war,

The uss monitor.

The national oceanic and atmospheric administration,

Or noaa, leads an effort here to discover the secrets

Of this revolutionary warship.

The story of the monitor has long been clouded by wartime propaganda.

The team hopes the wreck can provide the truth.

Underwater filming only shows a fraction of what's spread

Across the sea floor.

But using decades of carefully gathered data, we can now

Drain the atlantic ocean away to uncover the last

Resting place of america's second ironclad.

Emerging into view,

All that remains of a ground-breaking warship.

Like a drowned alien being,

The monitor lies upside down, her hull in pieces,

Clearly made of metal, just like the css virginia

With a thick belt of armor.

James: The distinctive form of the iron armor belt is still there,

The tip of the bow is sharply defined.

Right there is the grave of the iconic warship of the

American civil war.

Narrator: The monitor's greatest challenge comes in

Hampton roads, when she confronts the css virginia,

Just a day after the confederate ship destroys the cumberland.

To find out how monitor fought that day,

Maritime archaeologists carefully bring key parts of her to the surface.

Their most important target?

The first gun turret ever used in combat.

James: The recovery of the turret was an incredible

Undertaking and in that, what was discovered was a time capsule.

Narrator: It is analyzed at the baton conservation laboratory, in virginia.

Will: That way.

If you consider the story of monitor like a puzzle.

It's easy to get the outside edges of the puzzle because

You can use historical record, but understanding the exact story,

That's where the archaeology and conservation comes in.

Narrator: They discover that the turret is 21 feet across,

9 feet high and wrapped in 8 inches of armor.

Thicker than on any other ship afloat, including its rival,

The css virginia.

Researchers scan the turret using lasers

Looking for battle damage...

And find evidence of confederate fire,

But also proof that monitor's armor keeps it out.

Inside the turret; two gun mounts.

Armed with these new findings from the laboratory we can

Return to the drained landscape below the atlantic.

And use computer graphics to lift the wreck of the monitor

From the sea bed...

Turn her right side up and replace her turret.

Now this ingenious technology can be seen operating as its

Designers intended.

The turret sits on a brass ring,

Allowing it to rotate 360 degrees.

At a time when guns are typically fixed...

This instant maneuverability gives the union sailors a huge advantage.

As does the second gun.

When one fires...

The other moves back inside the turret to be reloaded.

Will: So, they would just switch between the guns.

Narrator: So how does the monitor compare with the

All-conquering virginia?

At first sight, the favorite seems to be the confederate ship.

She's over 100 feet longer than the monitor with 10 huge

Guns compared to the monitor's two...

And four-inch thick steel armor, although her fearsome

Ram was lost when she sank the cumberland.

In contrast, the monitor appears puny.

But she's faster and has even thicker armour on her turret.

And, although she only carries two guns,

They are superbly maneuverable.

March 9th, 1862.

A day after sinking the cumberland,

The virginia still threatens the union fleet.

So, the monitor is unleashed to challenge her.

In command is lieutenant john worden.

Anna: There was fear.

The men on the monitor recall an overwhelming feeling of silence.

Will: It's like the astronauts going into space, it's the

First time they did it, so sure there's fear but at the

Same time, you're on the cutting edge.

Captain: Fire.

Narrator: John worden's turret guns follow his enemy's every move...

(gunshots).

Firing shot after shot.

But virginia's armor does its job.

Monitor's shots bounce into the water.

For four hours, the ironclads duke it out...

Each failing to land a decisive blow.

Until a lucky shot from virginia manages to injure

The monitor's commander.

Anna: The pilot house is struck by one of the virginia's guns.

Sailor: Sir!

Anna: Immediately john worden is temporarily blinded.

There is sudden chaos on board monitor because he falls back

And says I am blind I'm blind.

Narrator: Monitor withdraws for a damage report.

When she returns, she finds the battlefield empty.

Virginia, also damaged, has returned to her base.

Anna: Neither could figure out how to kill the other vessel.

It was likely a draw.

Narrator: But by stopping virginia's killing spree,

Monitor becomes the most celebrated warship in the

Northern states.

James: It is the ship that has saved the union.

It becomes an icon.

It is a symbol of national pride.

Narrator: The battle of the two metal monsters fascinates

The world but they never fight again.

Two months later, union troops close in on virginia's home-port.

To keep her out of enemy hands, her own crew

Sends her to the bottom.

The fate of the monitor is more tragic.

Nine months after fighting virginia,

She's off cape hatteras, north carolina,

Under tow by another union ship.

It's a notoriously rough patch of sea known as

'the graveyard of the atlantic'.

Out of nowhere, a storm hits.

Anna: Monitor sailed right into this maelstrom.

Narrator: The waves badly damage her structure.

Water rushes into the hull.

The sheer weight of monitor's armor does the rest.

Will: It is kind of ironic that there's a potential that

What was meant to keep the monitor crew safe could have

Been its ultimate undoing.

Anna: The distress signal was a red signal lantern, and it

Would appear and disappear and then appear again and

Disappear and this, this went on for a while until finally

It appeared and was seen no more.

Narrator: Despite frantic rescue attempts, the monitor

Takes 16 men down with her.

Nearly a century and a half later, navy divers recover the

Remains of two sailors from inside the turret.

They are buried with full military honors at arlington national cemetery.

James: For a brief moment, the entire country stood united,

Long after the passions of that war, to honor these two men,

Who had come back to us from the depths and from

The turret of the monitor.

Narrator: The epic battle of the ironclads points the way

To the future.

The union navy builds 64 new monitor-class ships

During the next two years and on the confederate side,

The idea of metal warships

Is taken a decisive and deadly step further.

As the waters of charleston harbor begin to empty, the

Shattered remains of another lost union warship come into view.

The result of a terrifying new confederate weapon.

Narrator: Maritime archaeologist michael scafuri is investigating

One of the civil war's greatest mysteries

Outside charleston harbor, south carolina.

Michael: People were fascinated by the story and

Wanted to find out more.

To really understand what happened we needed to

Investigate from an archaeological point of view.

There are secrets still left to be discovered.

Narrator: In February 1864, charleston is a confederate stronghold.

Craig: South carolina was perceived as the heart and

Soul of the rebellion and charleston itself was the

Black heart of that rebellion.

Narrator: It's being blockaded by a squadron of 20 union

Warships, including six ironclads...

Part of a plan to squeeze the south economically.

One of them is the uss housatonic.

Made of wood but powered by steam, she is one of the

Union's most heavily armed ships.

On February 17th, at 8:40 pm, the bay is calm.

Suddenly there is a huge explosion...

(explosion).

The housatonic is gone.

The only clue: Eyewitness reports of a dark shape

Moving in the water.

Michael scafuri knows where the housatonic lies,

Now he wants to understand what happened to it.

But in these turbulent seas, visibility is nearly zero and

Underwater photography very difficu.

So powerful sonar probes the seabed.

Using this and other data, it's possible to see what no

Diver ever could and drain away the atlantic

To uncover an iconic wreck.

First, two iron water tanks emerge...

Next broken timbers, half-hidden in the sediment

But then, blowing away the silt uncovers the seabed of 1864.

And here she is...

The remains of the uss housatonic.

Whatever fate she suffered has been erased by the ravages of time.

Even fully revealed there are almost no clues.

But what if we could return to the moment just before she sinks?

By combining historical salvage records, and survey data we can.

Rebuilding the housatonic exactly as she was.

A towering fighting warship in perfect condition...

Except for this!

A hole in the hull deep below the water line.

This is still the age of the cannon ball and they usually

Shatter masts and punch holes above the waterline.

So, what caused this fatal wound?

For over a century, archaeologists scour

The area around the wreck site.

And eventually, about 1,000 feet from the wreck...

They find this.

The team recovers the remains and when they get them ashore they realize.

They've found the confederate's first

Operational submarine...

The hl hunley.

And it is what took the housatonic down.

In the warren lasch conservation center in charleston,

Michael scafuri and his team pour over every inch.

Michael: The techniques you use to investigate a site,

Are very much like a crime scene investigation.

You record everything and then you try and use that evidence

To figure out what happened here.

It was a product of the american civil war and spurred

On by the needs of that war to develop new technologies.

Narrator: First question, how did it move?

The archaeologists find no sign of an engine.

But they do find this...

Johanna: This is a wrought iron crank and that's how they

Moved the submarine.

They hand-crank it.

The hand crank moved a flywheel, the flywheel moved a

Series of mechanisms, and then that moves the propeller.

Narrator: Next, how did the crew breathe underwater?

There's no evidence of any way to refresh the air...

Which means that eight men crammed into this metal tube

Must rely solely on the air already inside.

The team calculates that there's enough oxygen for just two hours.

Severely limiting their range of operations.

Finally, the most important question of all?

Just how did this hand-cranked short-range submarine manage

To ambush and destroy such a powerful enemy?

Narrator: The confederacy's ground-breaking submarine,

The hl hunley.

Inside, there's no sign of a weapons system.

But outside, it's a different story.

Johanna: We have clues all over the submarine that tell

Us what happened.

This is the spar, it was attached to the bow of the

Submarine, the lower part of the submarine.

Narrator: The 16-feet long spar presents a puzzle.

Michael scafuri thinks it isn't a weapon itself...

But the delivery mechanism for a weapon and that weapon

Is an underwater bomb.

In the civil war, they call such weapons by a very modern name, torpedo.

James: In the 21st centu we think of a torpedo as

Something that fires out of the submarine, when originally

Invented in the early 19th century the torpedo was an

Underwater explosive charge.

Narrator: If this is how the hunley attacked, then she

Would need to get within touching distance of her prey.

But how exactly?

For years, historians believe the rebel submariners

Physically attach the bomb, with a barbed spike then

Detonate it from a safe distance.

But other evidence found near the wreck site suggests that

This isn't what happened.

A copper sleeve, which looks like it was created to hold

The explosive in place.

Michael: The copper sleeve was peeled back from the force of

The explosion, clearly showing us that the torpedo was in

Fact on the end of the spar when it went off.

Narrator: Based on the evidence from the drained

Wreck and work in the laboratory it's now possible

To piece together what likely happened.

The confederates are desperate to smash the union's naval

Blockade of charleston.

Craig: The confederacy, because they knew they were

Inferior in the conventional weapons of war, had to turn to

New, creative devices.

James: You try to out-smart the enemy, you try to out-innovate the enemy.

Narrator: The housatonic lies at anchor.

Suddenly, the crew spot a ghostly shape.

Michael: They weren't entirely sure what it was at first.

It looked like a log on the water, maybe a porpoise.

Narrator: In fact the hand-cranked submarine

Is headed straight for the union warship.

Michael: Something like this had never been seen by the

Crew before they would have been terrified.

Narrator: Historians don't know if the hunley's crew tries

To attach their bomb and escape...

But they do know that with the hunley just 16 feet from its prey.

(explosion).

The torpedo does its fatal work and the housatonic

Sinks in minutes.

A new age of naval warfare has begun.

James: Hunley proves to be the first submarine ever to

Sink an enemy warship in combat.

Narrator: But there's a final mystery here.

The hunley never returns to its base.

No-one has ever been sure why.

Michael: With the discovery of the h l hunley a great mystery

Had been solved.

However, the real work begins with discovery, we could then

Begin to investigate from an archaeological point of view.

Narrator: The most obvious explanation...

The hunley is destroyed by her own bomb.

(explosion).

Ken nahshon is a us navy engineer;

His job is to test underwater explosives.

Ken: It's been a historical mystery for well over

100 years and really people have always wondered

What happened to it.

Narrator: How big is the blast and what damage could it have

Done to the hunley?

Ken: We constructed a full-scale replica of hunley's torpedo,

Filled the torpedo with black powder that matches

The black powder used at the time and then set off the explosion.

(explosion).

Narrator: Packed with 135 pounds of gunpowder...

The torpedo is seriously powerful, but the results are unexpected.

Ken: Once the explosion goes off, it generates a

High-pressure wave emanating from the explosion,

As well as a bubble.

That bubble expands and contracts what would happen

Is a high velocity jet would occur, where basically the

Bottom of the bubble comes in on itself and forms this high

Velocity water column that would have punched a hole

Right through housatonic, while leaving hunley

Completely unaffected.

Ken: The most surprising conclusion we had was the

Submarine heaved quite substantially...

However, it was not substantial enough to cause injury.

Narrator: And there is other evidence that

Hunley survives the explosion...

The bodies of all eight crewmen found by archaeologists

Inside the wreck in an excellent state of preservation.

Before they are removed for burial, they are scanned,

Photographed and analyzed.

Michael: We have their remains and we didn't find any injury to the crew.

Narrator: So, if the explosion didn't kill them, what did?

Could the pressure wave have cracked the hull causing flooding?

The evidence suggests not.

Michael: There was no sign of panic on board.

No-one is out of position,

Nobody tried to climb over their neighbor

And you would expect that in a drowning scenario.

Narrator: Michael scafuri believes that there could

Be anotherxplanation.

Michael: There's a strong case to be made for them simply

Staying on the bottom too long, miscalculated how much

Air they had and uh simply went to sleep,

Not to wake up again.

Narrator: Today, the investigation continues.

Johanna: How they were able to hand crank a submarine

Four miles attack a big ship.

The fact that they thought they could do it and they

Did it, that's, that's a most remarkable thing.

Narrator: In charleston's magnolia cemetery,

A poignant memorial to a pioneering crew.

Michael: The fate of the hunley crew was a mystery

For 136 years, so it was appropriate for them to

Eventually be given a proper burial after

136 years of being lost at sea.

This is an archaeologic project but this is also the

Story of a number of people...

8 crew in hunley and five on housatonic who lost their

Lives and it's important that we get their stories straight.

Narrator: The world's first successful fighting submarine...

(explosion).

Is at the forefront of a civil war arms race.

Draining the oceans around mobile, alabama,

Reveals astonishing evidence

That the race isn't over yet.

Narrator: By 1864, two years after the game-changing

Development of the monitor...

This is the face of naval warfare.

The uss tecumseh.

A bigger, better ironclad.

Designed to be impregnable to enemy fire,

It's 50 feet longer than the monitor,

Has thicker armor and two massive 15-inch guns.

Tecumseh is one of 4 ironclads in a fleet of 18 union warships.

Their target is mobile bay, alabama.

One of the last confederate ports in the south.

If the union can capture it, the war could be over soon.

As the fleet enters the bay, there's an explosion...

(explosion).

And the mighty tecumseh is hit.

Almost all her crew are lost.

The only union ironclad ever sunk in battle.

Maritime archaeologist james delgado is in mobile bay,

Studying the wreck of tecumseh and trying to work out what sank her.

James: There are still amazing secretbeneath the waters of

Mobile bay that most people don't see...

Sunken vessels lost in the battle.

Narrator: The team prepares to use side scan sonar and a

Magnetometer to probe the seafloor.

Anna: Ready?

James: Okay, so we're in, what altitude are we flying the head at?

Crew: We're about 15 feet off the bottom.

James: Okay and speed's running at about?

Crew: At about 4 knots. James: Yeah, good.

Crew: Returns looking smooth.

James: Whoa, whoa, whoa okay, what are we coming up on here?

Crew: Does that look like something?

There we go, I think we might have a shipwreck.

James: We're on it.

Narrator: The scanner detects a large iron object.

It's in the right place.

James is convinced it's tecumseh!

James: But there's a lot of mud here, looks like given

Stuff coming on it, I think this thing's buried.

Narrator: The mud and silt of 130 years

Obscures much of the wreck.

Only emptying mobile bay of water can reveal

What's really down there.

And using the expedition data we can do just that to try and

Solve one of the final mysteries of the american civil war.

As the water drains away...

A tantalizing sight emerges...

A section of an iron hull buried in the seabed...

And based on the survey data,

We can drain away the mud as well.

Underneath...

An incredible sight.

A massive iron monster, 223 feet long

Lying upside down.

Its spine slowly corroding away.

Once one of the world's most powerful vessels,

The pride of the union fleet...

Now seen in the clear light of day for the first time

In over 150 years.

A closer look reveals a clue.

Under the waterline, a large dent in the hull,

8 feet long and 5 feet wide

And more evidence...

Metal seams split apart, broken with explosive force.

So, could it be the victim of another confederate submarine?

Union spies reported rebel subs under construction,

But there are no records of them being active here.

What else might have caused it?

Lying all across the bay...

Piles of junk, hundreds of yards long.

Shipwrecks, bricks, and wood pilings.

James: If you were to drain mobile bay you would see still

To this day, a number of obstructions, that were placed

There by the confederates to keep the union navy out.

Narrator: None of these could cause the severe damage

Discovered on the tecumseh.

But that's not all that the confederates place here.

They also deploy these...

A terrifying new weapon; known today as a sea-mine,

But back then, also called a torpedo.

A torpedo unlike the one carried by the hunley submarine.

Instead held just under the surface by a weight and chain:

Primed to detonate on contact.

(click and explosion).

This underwater killer is one of the confederate's

Most successful maritime weapons,

Sinking or damaging 43 union ships.

And in mobile bay, there are up to 180 torpedoes...

Laid row after row, in a dense, checkerboard pattern.

James: By August of 1864 the confederates had built,

Not only an obstacle course but a gauntlet, through which the

Union navy was going to have to fight its way through.

Narrator: With information from the drained landscape,

And the latest historical research,

It's clear what happens here.

Commanding the union fleet is admiral david farragut

On the steam and sail-powered uss hartford.

Farragut knows he faces underwater torpedoes,

But he doesn't know where they are.

He sends in the ironclads first...

Carefully, in single file.

Leading the line, the tecumseh.

She fires the first shot at the rebel-held fort.

Then, as the fleet enters the bay...

(explosion).

Craig: Gigantic explosion, the bow wheeled up,

Then down into the bay,

The ship plunged downward, it's stern rising in the air,

The bronze propeller still spinning.

Anna: Within the space of about 30 seconds,

The tecumseh went bow down and sank.

James: It's a shocking moment, but for farragut history is

Made when he reportedly says,

"damn the torpedoes full speed ahead",

The order was given to keep going.

Anna: They report hearing the fuses of torpedoes clicking as

They're moving through but none of them go off.

Narrator: The union fleet breaks through and despite losing the tecumseh,

Farragut's boldness is rewarded.

Mobile bay falls.

For the rebels, it's the beginning of the end.

Craig: The size of the confederacy was quite literally shrinking.

Narrator: Nine months later, peace returns to america.

Draining the secrets of the american civil war reveals the

Courage of those on both sides, who risked everything

For their cause.

And a technological revolution that transforms

The navies of the world.

Captioned by cotter captioning services.