Original subtitles

NARRATOR: Off the coast of France,

an international team is exploring

a hidden battlefield...

looking for the secrets

of how the greatest naval invasion in history unfolded.

Buried here is a treasure trove of ships, tanks,

and potentially unexploded mines.

These are the wrecks of D-Day... June 6, 1944.

For years, Hitler had devastated Europe, killing millions.

Now was the time for the Allies to make their move.

MAN: It was an all-out gamble.

It was nothing less than the history of Western civilization.

NARRATOR: But the odds were against them.

MAN: It's hell.

It's about as bad as combat can get.

NARRATOR: Three years in the making,

this was the most epic struggle of the 20th century.

These are the men who made the difference.

You should understand that.

NARRATOR: D-Day required the best minds in the military,

working with scientists and engineers...

MAN: D-Day is a triumph

of technology and engineering.

MAN: The guys that planned the logistics for this

were unbelievable.

NARRATOR: ...new machines

to break through Hitler's vicious defenses,

ingenious and untested ways to deliver an invading army.

MAN: I always knew it was big,

but I think this makes you feel how big it is.

NARRATOR: Today's expedition investigates

how the Allies tipped the odds in their favor.

Whoa, look at that.

NARRATOR: And brings veterans back

to the place where they nearly lost their lives.

MAN: Bet you never thought you'd see that again.

No.

NARRATOR: New technologies and veterans' memories come together

to reveal this hallowed ground.

The hidden battlefield is one of our most sacred charges.

NARRATOR: Right now on NOVA, "D-Day's Sunken Secrets".

Major funding for NOVA is provided by the following:

NARRATOR: Along the north coast of France

is the picturesque region of Normandy.

(birds chirping)

Charming villages,

farms with their patchwork of small fields,

and beautiful beaches where Parisians come for a holiday.

But few realize that just beyond these tranquil beaches

is evidence of the biggest

and the most dangerous naval invasion of all time.

The violence of that battle still lives

in the World War II wrecks that lie just off the coast.

These wrecks tell the story of D-Day.

(explosions)

June 6, 1944.

7,000 warships...

11,000 airplanes...

and 200,000 men...

Crossing at dawn from England to these beaches at Normandy

to liberate Europe from the Nazis.

Four years earlier, Hitler had conquered most of Europe,

killing millions

and setting up the most epic struggle of the 20th century.

All along the north coast of Europe, the Nazis had built

a vicious wall of defenses to stop just such an invasion.

D-Day took three years to organize

and was the Allied Forces' best chance to retake Europe.

But the odds were against them,

and the future of the free world hung in the balance.

It has now been 70 years

since this battle that changed history,

but the magnitude of that invasion still inspires awe.

How did the Allied Forces of Great Britain,

the United States and Canada, depleted by years of war,

manage to pull it off?

NICK HEWITT: One of the things we are learning

is to treat the evidence of 20th century battlefields

as proper archaeology.

NARRATOR: Nick Hewitt,

an historian at the National Museum of the Royal Navy,

says that these D-Day wrecks can tell us things

no official document can.

HEWITT: The beauty of the D-Day underwater battlefield

is the evidence is still there.

It's all laid out for us.

All we have to do is interpret the evidence to tell the story.

NARRATOR: What is the true story of this invasion?

It's referred to as D-Day,

but what do these wrecks reveal about the invasion

and how long it took to secure a foothold in Europe?

And what tales do they tell us about the necessary engineering

that made this all possible?

HEWITT: D-Day is a triumph of technology and engineering.

And what you see is specifically engineered solutions

to specific problems.

NARRATOR: Buried here are inventions

of scientists, engineers, and even maverick businessmen,

some of the unsung heroes

drafted into this immense war effort.

These wrecks comprise one of the largest

underwater archeological sites in the world,

and it is beginning to get the closer examination it deserves.

To understand this hidden battlefield

and these inventions, an international team

of oceanographers, historians and archeologists

has set out to examine the evidence buried here.

This is a new one, yeah.

It's right off of Utah beach.

NARRATOR: There are hundreds of ships,

as well as tanks, guns, and potentially unexploded mines.

The expedition team uses the latest in sonar technology

and even deep-water submarines

to investigate the remains of this epic naval battle.

Undiscovered evidence is being charted and explored,

like this American Sherman tank,

one of the iconic weapons of World War II.

How did this weapon, intended for a land battle,

end up here, intact and underwater?

It's mysteries like this that the expedition will investigate

over the next six weeks.

SYLVAIN PASCAUD: There are few areas in the world

where you have so many wrecks concentrated in one area.

NARRATOR: Sylvain Pascaud, the director of the expedition,

believes a systematic exploration

of this "lost fleet" is necessary

to give a true picture of what this battle really was.

Oh, look at that.

HEWITT: When we think of the D-Day landings,

we think of a land battle.

We think of great movies, we think of boots on the beach.

But actually, 6th of June 1944

was the biggest, most complex amphibious landing in history.

(explosions)

NARRATOR: The expedition starts off with a sonar-equipped catamaran

named the Magic Star.

Onboard is the latest neration sonar,

submerged underwater in the middle of the boat.

Sonar uses sound waves transmitted through the water

to image what is below on the ocean floor,

like this British ship.

For a solid month,

the Magic Star will sail back and forth

in up to 40 miles stretches...

...each pass revealing long strips

of this hidden battlefield.

It's like mowing a lawn...

a 200-square-mile lawn, that is...

with each pass overlapping the last

to make sure they don't miss a spot...

VoilÃ.

Très bien.

NARRATOR: ...or a ship on the ocean floor below.

This survey phase will reveal potential targets

for further investigation, like the mysterious sunken tank.

We're right at the edge of the caisson.

NARRATOR: Onboard is Andy Sherrell, who leads the team of sonar experts.

Ralph will run you through our target.

ANDY SHERRELL: We collect one line of data at a time,

but as you can see here, we're combing line by line by line.

We're trying to build a very large

underwater archeological map of the whole area.

NARRATOR: This area covers the site of the D-Day naval battle

where the Allied Forces,

led by Britain, the United States, and Canada,

sought to regain a foothold in Europe.

Four years earlier,

the Nazis had conquered France along with much of Europe.

(explosions)

Ever since, the Allied Forces had planned in secret

how to fight back.

They needed to win a toehold in France,

and then could drive up to Berlin from the west.

The Soviet Union would push in from the east,

choking Hitler in the middle.

The stakes could not have been higher.

HENRY HENDRIX: What is at stake

was nothing less than the history of Western civilization.

It was an all-out gamble.

It was pushing all your poker chips

onto the center of the table.

NARRATOR: Captain Henry J. Hendrix,

the chief historian for the U.S. Navy,

says what was involved in pulling off D-Day

is hard to even imagine today.

HENDRIX: The Germans had literally years

to prepare the defense of the beaches.

So they are ready.

They know if Germany is to be defeated,

the Allies have to reenter the continent somewhere.

So the question is really where?

NARRATOR: The options for the invasion were limited,

and they had already tried unsuccessfully

in other locations.

Two years earlier in France,

the Allies tried to capture a port in a town named Dieppe.

That battle against the fortified German positions there

was a disaster.

More than 60% of Allied soldiers were killed or captured.

This failure haunted British Prime Minister Winston Churchill

and changed the course of the war.

In response to previous failures,

President Roosevelt and Churchill

met several times in secret to create a new strategy.

The plan they devised

was to overtake the region of Normandy from the Nazis.

And the naval invasion was just the beginning.

The entire plan was codenamed Operation Overlord.

And the naval invasion It would be a surprise.

The Nazis had expected an invasion at Calais

because it was so close to England and had a port.

Instead, the decision was to go further down the French coast

where there were no large ports

and target the beaches of Normandy

with a massive amphibious landing...

a much more difficult operation.

RICK ATKINSON: In an amphibious operation,

generally, there's no middle ground.

You either succeed or you don't.

You get ashore and you move inland

or you get thrown back into the sea,

unlike most battles where you can retreat

and fight again the next day.

You can't retreat in an amphibious operation.

Overlord in Normandy is really the big gamble

about whether democracy as we know it

was going to continue and survive and grow and flourish

and that people would be free

as we thought that they should be free,

or whether Nazism

and the atrocities that Hitler was committing,

genocide, was going to succeed.

NARRATOR: In the end, five landing beaches were chosen:

Two American, one Canadian, and two British.

They were given code names

of Utah, Omaha, Gold, Juno and Sword.

But even its chief architect

wasn't sure this plan would work.

The night before the invasion,

General Eisenhower wrote a letter

taking the blame if it failed.

EISENHOWER (recording): My decision to attack at this time and place

was based upon the best information available.

The troops, the air, and the navy

did all that bravery and devotion to duty could do.

If any blame or fault is attached to the attempt,

it is mine alone.

NARRATOR: Perhaps the best way to understand

why Eisenhower was so worried is to stand on Omaha Beach

and see what the Allies were up against.

Omaha Beach is an excellent defensive location.

If you're the Germans, what you want to be able to do

is kill anything on the beach.

NARRATOR: Adrian Lewis, a former Army Ranger,

is a history professor at the University of Kansas.

And he has taught military strategy to West Point cadets.

The geographic formations here,

the terrain, makes it excellent.

From one end where the landing takes place

to the other end here is about four miles long.

NARRATOR: Lewis says any fighting strategy

must begin with understanding the geography

of the battlefield.

Omaha Beach is banana shaped.

That banana shape is important.

So instead of having your weapon systems pointing out to sea,

what you would do

is actually have them pointing into the beach.

So if I put machine gun positions,

artillery positions on this flank,

and then I put more on this flank,

instead of having them point out to sea,

I'm actually having them pointing in,

and that's what the Germans did.

(gunshots)

NARRATOR: This inward pointing fire, or interlocking fields of fire,

created a deadly kill zone on the beaches.

This was a huge advantage for the Germans.

Excellent terrain for putting in a defense.

As a matter of fact, if I were doing this thing,

I'd rather be on the German side.

NARRATOR: In addition, the cliffs that surround the beach

gave the Nazis the high ground.

It seemed that nature gave them every advantage

in this crucial battle.

HENDRIX: You're up against the weather.

You're up against the tide.

You're up against the beach.

And when you are dealing with forces of that size,

it's hard to get it done in the right way.

NARRATOR: This area off the coast is known for unreliable weather

and some of the strongest ocean tides in the world.

Those conditions are even difficult

for today's expedition.

PASCAUD: We've got three challenges:

The weather, the tides, and the current.

I just cannot imagine 5,000 vessels with 200,000 men

in conditions like that.

If you disregard the weather, the current and the tide,

you will be going absolutely nowhere.

NARRATOR: Ocean levels here

can rise and fall up to 25 feet a day.

The effects can easily be seen

over the course of a few hours on the beaches.

Here when the tide is out, the width of the beach increases

a full 300 yards wider at low tide.

The significance of that is it meant the soldiers on D-Day

would be exposed for much longer to the deadly Germany crossfire.

D-Day planners needed to understand every detail

about the geography of this battlefield

to plan for the assault.

But how do you get that information

when the entire country is under enemy control?

Evidence of the incredible effort to figure this out

still exists at the United Kingdom Hydrographic Office,

one of the world's leading producers

of navigational charts.

This building was an important intelligence site,

its location a state secret.

In fact, the building was camouflaged

to hide it from Nazi bombers.

Inside, top-secret documents still exist.

"Neptune" was the code name for the naval operation.

These artifacts aren't quite like the sunken wrecks

off the coast of Normandy, but they are important evidence

of ways the D-Day planners found around the obstacles:

An effort that began long before the invasion.

CHRIS HOWLETT: You have mines here.

Barbed wire entanglement here.

NARRATOR: Cartographer Chris Howlett

explains that mapping the Normandy region

was an extraordinary top-secret operation

that required math, science and daring spy missions.

(cameras snapping)

Low-flying aircraft were dispatched over the beaches.

And surveillance photographs

were taken at intervals throughout the day,

documenting the changing tides.

(cameras snapping)

HOWLETT: These black lines are where the water line was

on different tides.

NARRATOR: Why was this useful?

Using those different tide levels,

mathematicians could calculate

the exact slope of the different beaches,

necessary to figure out what vehicles could be used.

Knowing every detail of the beach was crucial.

At Dieppe, the Allies discovered only after landing

that their tanks could not get traction on the beaches there.

Every way of getting information was used.

Even past vacation postcards were requested.

HOWLETT: They put out a public request for the people of Britain.

"Any postcards you collected

"in your holidays to France before the war,

send them in to us and they may be of use."

And millions of postcards were sent in.

NARRATOR: These postcards gave essential information

about what the coast of France,

by now in enemy hands for four years, looked like.

But not all the necessary information

could be gleaned from a safe distance.

Just off the Nazi-controlled beaches lurks an X-Craft.

Inside this mini-submarine are five underwater spies.

HEWITT: Perhaps one of the earliest phases of the battle

was the survey and preparatory work

carried out by men serving aboard miniature submarines...

the X-Craft... who were effectively secret agents.

NARRATOR: The X-Craft were 50 feet long and barely five feet high.

Some missions lasted two weeks in these cramped quarters.

The surveillance gathered was used in making these maps,

including some from the perspective of the sea,

showing visible landmarks on the beach

like church steeple or houses.

These were crucial for navigating the landings.

HEWITT: They came up with a novel idea.

The view at the bottom here

is the view that you would expect to see

if you were coming in from a landing craft

at any given point along this map.

NARRATOR: Jim Booth was a member of this elite submarine force,

venturing into mine-filled, Nazi-controlled waters

with barely any navigational guides.

BOOTH: Navigation of course was difficult

because then, there were no SAT and air.

A classic old-fashioned navigational trip:

Pencil and ruler and gyrocompass.

NARRATOR: Booth's mission was to go ahead of the invasion force

and set up light beacons

so the huge armada of Allied ships would know where to go.

His submarine was assigned to the British landing beach

codenamed Sword, the furthest east of the five beaches.

He would be one of the first soldiers in action on D-Day.

He was in position at 0100...

military terminology for 1:00 a.m.

Today, Jim Booth has come back to Normandy

to take part in the investigation.

(voice over radio)

This is no leisurely retirement cruise...

the D-Day expedition has brought in a team from Canada

with two deep-water submarines.

HEWITT: The veterans who stormed

the beaches of Normandy,

they're the most incredible people.

No one can bear witness with the same kind of emotional intensity

that someone who was there can.

We're losing about 600 veterans every day.

When they slip away, they are in the shadows forever.

NARRATOR: For the first time in 70 years, Jim Booth will go underwater

off the coast of Normandy, just like he did for D-Day.

There is a very small amount of worries

because he's 92.

I haven't been in a submarine at all since then, no.

HEWITT: I think you will find you can see a lot better

from that one than you could in yours.

Well, we had no windows of course at all.

NARRATOR: Ironically, this time

the submarine is even smaller than the X-Craft.

But Jim Booth will only have to stay in the submarine

for an hour

instead of the four days he did before D-Day.

Today's dive is in the exact same location

off of Sword beach.

His shipmate is military historian Nick Hewitt.

HEWITT: Any second now,

you're going to be underwater for the first time in 70 years.

Here we go.

Look at that!

Isn't it amazing?

It's reasonably clear today too, isn't it?

MAN: Pickup target straight ahead.

The wreck's about 15 meters below.

HEWITT: There's a shadow.

There is something here.

MAN: Roger, I've got visual.

HEWITT: Jim's role on the 6th of June

is to mark the safe channel through the enemy minefields.

So Jim has to go out with a small group of men

in advance of the landings,

navigate themselves to exactly the right spot,

surface alongside, we must remember, a minefield,

and light a beacon

so that the incoming ships can pass safely through.

So we need to keep our eyes peeled.

NARRATOR: It was in this spot off of Sword beach

that Jim Booth placed the beacons on D-Day.

HEWITT: Did you have an understanding

of how enormous the scale of it all was?

Almost everybody was just a tiny cog in this vast wheel.

NARRATOR: His sub surrounded by mines, Booth and the X-Craft crew

had to find the exact location to set up the beacons.

But with no lights on shore or radar, how did they do it?

It was very, very complicated.

One has to remember that all of the navigation aides

had been switched off because of security.

We knew we were in France.

It didn't take very long to recognize it was a church tower.

We did recognize that.

NARRATOR: In the end,

Booth and his X-Craft crew navigated using the landmarks

that had been mapped by the Hydrographic Department.

Booth says it was the Allies' attention to detail

in the planning that made the difference,

and that was a direct result

of the lessons learned from the disaster at Dieppe.

Dieppe was really intended to be a test run for Normandy.

It did all the things wrong.

Those lessons were learnt,

and this was put into good force for Normandy.

NARRATOR: But the one thing the Allies couldn't control

was the weather for the invasion,

and the forecast did not look good.

By May 1944,

two million soldiers were in southern England,

waiting for the go ahead from their commanders.

And with 11,000 airplanes and 7,000 ships involved

in this complicated operation, decent weather was required.

But the science of weather prediction

was not what it is today.

(thunder rumbling)

General Eisenhower and his Supreme Allied Command

had only limited information,

since satellites and weather RADAR

wouldn't be invented until after the war.

Instead, weather data was collected

at remote weather stations

and sent to the UK Meteorological Office

in Essex, England.

Records like these, dating back 150 years,

are still archived here,

including those for the D-Day landings.

These maps detailed weather patterns

and were meticulously drawn to chart moving storm systems.

CHRIS TUBBS: These were the weather maps that they used for that process.

The maps were produced every three hours,

whereas nowadays they would be only done

every six or 12 hours.

NARRATOR: High and low pressure systems...

the atmospheric conditions that determine the weather...

were charted and analyzed at the headquarters.

The low pressures are basically bad weather:

Strong winds, rain, a lot of clouds.

The high pressures are mainly fine weather:

Lack of clouds and quite warm temperatures,

in June anyway.

NARRATOR: At the center of the operation

was Group Captain James M. Stagg.

His responsibility was to track the weather data

and report it directly to General Eisenhower.

He kept a personal diary

that is still held at the Meteorological Office.

It shows the enormous pressure he was under.

The invasion was originally planned for June 5.

MAN: "Saturday June the 3rd.

"A day of extreme strain.

"The weather situation got worse.

"Two depressions below 98 millibars at one in June.

Who could have forecast this?"

(thunder rumbling)

This map was from June the 3rd, and this is showing

typical bad early summer weather in the UK.

NARRATOR: Before D-Day, there were several storms lined up.

TUBBS: We've got a succession of low pressures across the charts:

One here, one here, one to the northwest.

These are going to keep the weather what we call unsettled...

so, clouds, rain, gale force winds in the Channel.

Going to stir up very rough seas.

So anybody who is on a boat crossing the Channel

would be in danger.

MAN: "June the 4th, 1944.

"At 0415 conference this morning,

assault for tomorrow definitely cancelled."

NARRATOR: The bad weather would limit air support

and create treacherous conditions

for ships on the Channel.

The invasion force is put on hold,

but time is running out.

MAN: "Today, it began to appear

"that there might be a temporary fair interval Monday night.

Should we advise to make use of it?"

NARRATOR: The timing of the invasion had been selected

to correspond with the lowest tide of the month.

This would give the Allies maximum time

to unload men and equipment.

With the tide low and coming in,

ships can unload and be carried out to sea on the rising tide.

If the tide were high and going out,

boats would get stuck on the beach as the water receded.

HENDRIX: If you are on a ship

that makes land or gets close to land at high tide

and suddenly the tide turns against you

and the water is running out, you either need to leave then

or your ship is actually going to come

and ground in the mud flats.

NARRATOR: Because of the changing tides,

Eisenhower could only wait one more day.

If the weather didn't clear,

the invasion would have to be postponed for weeks.

MAN: "I'm now getting rather stunned.

It is all a nightmare."

NARRATOR: Every day they waited, there was an increased chance

that German intelligence would discover

the huge invasion force poised at the coastline

and realize that the invasion was coming.

If discovered,

the crucial element of surprise would be lost.

This is the chart for Monday, June the 5th.

This was the original D-Day.

There were some crucial observations

which made some of the meteorologists start to think

that the 6th could be possible.

And these operations were up here

in the north of the Atlantic.

And interestingly, they marked things on here

which we don't nowadays, called "col."

NARRATOR: Cols are a gap, or interval of calm,

that can exist between bad weather systems.

TUBBS: Cols exist between areas of low pressure.

And these were quite important for this situation

because they knew that if they could get into an area of a col,

the chances for getting the right weather for the landings

were better.

It wasn't a definite, but it was a possibility.

It's Eisenhower's decision.

The momentum had already built up.

"I've got everybody locked and cocked, ready to go."

The fact that the weather was so bad

actually made it one of his harder decisions.

MAN: "Monday June the 5th.

"After one hour's rest, met conference at 0300.

"Fair interval confirmed

"and invasion put on final and irrevocable decision.

Whatever the outcome, the decision is taken."

NARRATOR: Following this weather report from Stagg,

General Eisenhower ordered the invasion to begin.

Later, he broadcast his blessings to the troops.

EISENHOWER (recording): Soldiers, sailors, and airmen

of the Allied Expeditionary Force,

You are about to embark upon the Great Crusade

toward which we have striven these many months.

The eyes of the world are upon you.

Good luck,

and let us all beseech the blessing of Almighty God

upon this great and noble undertaking.

NARRATOR: D-Day had begun, and there was no turning back.

The armada of Allied ships left England

and would sail through the night

to five different landing beaches.

HEWITT: The scale of it is almost inconceivable.

It's 7,000 ships.

ATKINSON: And they include not only the ships

that are carrying the infantrymen

who are going to the beaches,

but they include bombardment ships.

HENDRIX: Battleship after battleship.

And destroyers.

ATKINSON: All of those have to be launched from Britain.

There's intense choreography.

"You will go here, you will go there,

you'll do it at this hour," and so on.

HENDRIX: It was the most massive naval force

that's ever been assembled.

HEWITT: D-Day is without doubt

the single biggest, most complex amphibious landing in history.

LEWIS: The naval plan Operation Neptune

encompasses 50 miles of beachfront,

hundreds of thousands of soldiers,

thousands of ships and landing craft.

The magnitude of it is incredible.

NARRATOR: The landings were set for 0630, early the following morning.

On the shores of Normandy,

the Germans could only see the bad weather

and thought that it would prevent any immediate invasion.

They also did not see that just off the coast

were a handful of small X-Craft submarines.

Onboard one was Jim Booth.

BOOTH: It was a hell of a time ago.

69 years.

Obviously, it is emotional, very, emotional.

It is very emotional indeed.

It was sort of in the direction of the yacht,

but where the last ripples are.

That sort of distance from here.

We saw the soldiers playing football.

Here, you know.

That was the day before, actually.

So they didn't know, did they, what was coming.

NARRATOR: Off the coast, Jim Booth and the X-Craft submarines

were not alone.

An 18-year-old Robert Haga from Virginia

was aboard the USS Chickadee,

one of the ships that left England ahead of the armada

to perform the essential task

of clearing the minefield that the Nazis had laid.

(explosions)

An extremely dangerous operation.

"June the 5th, 1944.

Underway for France."

NARRATOR: Haga kept a personal diary of these historic days.

HAGA: "The invasion will be early in the morning.

We are to go in first and sweep a channel clear."

NARRATOR: The Germans had heavily mined the English Channel

as part of their Atlantic Wall.

Mines in World War II

are like the IEDs of today's wars in Iraq or Afghanistan...

low-cost weapons, but highly lethal.

The Magic Star team

has not found any unexploded German mines so far,

since they were largely cleared for safety after the war,

but can the sonar reveal their effect?

This is pointed up here, so it looks like a bow.

It's broken off.

I think it hit a mine.

NARRATOR: They come across a Canadian ship called the Fort Norfolk.

Its bow was broken off by a mine.

SHERRELL: That is unbelievable.

That is a gorgeous, gorgeous wreck.

NARRATOR: One mine can have a disproportionately large impact,

sinking a whole ship full of soldiers and equipment.

HEWITT: The important thing about all naval warfare

is the equipment or the men contained in a ship

are an awful lot easier to destroy at sea

than they are once they've got ashore.

A single mine could drown all those men

and destroy all their equipment.

It would take days of fighting to do the same job on land.

NARRATOR: One place you can safely see some of these mines

and other military hardware is the Museum of Normandy Wrecks

in a little town called Port en Bessin.

It is a private collection of D-Day military equipment

salvaged off the coast here.

Axel Niestle, an expert on the German military,

says the Nazis used four different kinds of mines

in the ocean off Normandy.

The most common was a contact mine.

The whole body is filled with explosives.

Once it goes up close to the ship,

it can sink a battleship.

NARRATOR: These mines were anchored to the ocean floor

and floated just below the water's surface.

(explosion)

The horns are detonators,

something like a very large off/on switch.

And once the ship hits one of these detonators here,

a chemical reaction is started.

The detonator is ignited, which is a primer,

and then the full charge is going off.

NARRATOR: The Nazis had heavily mined the bay just off the beaches,

and so the Allies had to sweep lanes clear

just before the landings.

HENDRIX: We waited until the last instant.

Minesweeping tells you where the landing is going to occur.

If you begin too early,

then you have already tipped them off

on where the operation will be focused and concentrated.

NARRATOR: Haga's boat was third in a line

in the minesweeping operation off of Omaha beach,

next to the USS Osprey.

"At 1800, the USS Osprey was hit by a mine."

(explosion)

I was on the bow of the ship.

And when it hit,

the ship just lifted out of the water and exploded.

This mine hit the magazine

that carried all the ammunition in the ship.

NARRATOR: Six men on the Osprey were killed in the initial blast.

These were the first casualties of D-Day.

HAGA: A lot of the crewmen were blown out into the water

and they were badly burned.

We were throwing rope ladders over as fast as we could,

but they couldn't see.

So we were having to sometimes hook onto each other

to pull them up, and the skin would come off their arms.

I still have bad memories about that.

NARRATOR: Haga has returned to Normandy as part of the expedition

and wanted to see

the newly installed Navy Memorial at Utah Beach

that honors many of his fellow minesweepers.

The mine sweeping operation went on

in view of the German- controlled beaches

in the hours leading up to the invasion.

Everyone was haunted by the possibility

that the soldiers there would sound the alarm.

But that never happened,

perhaps because as part of the operation,

the Allies made a massive effort to mislead Hitler

into thinking that the invasion

would be further north, along the coast near Calais.

Fleets of fake military gear

were positioned in England across from Calais,

and an extensive counterintelligence campaign

was organized to deceive the Nazis.

ATKINSON: It's one of the most

brilliant deceptions in the history of warfare.

It's right up there with the Trojan horse.

NARRATOR: Not the Trojan horse,

but on the night before the invasion,

another wood vehicle was slipping behind enemy lines

unnoticed under the cover of darkness.

There are two large rivers that cross the road

between Normandy and Paris:

The Caen Canal and the Orne River.

The Allies realized they needed to capture these bridges

and other strategic targets before the landings

or risk getting trapped on the beaches.

It was urgent to get men behind enemy lines

and secure these targets.

But how do you do that without modern Apache helicopters?

One possibility was dropping paratroopers.

But loud airplanes could alert the Germans,

giving them time to blow up the bridges.

So instead, the job fell to men like Kermit Swanson,

a farm boy from Minnesota

trained to fly a silent wood glider

behind enemy lines.

Our mission was to fly that glider over there and land

and try to keep from killing ourselves.

If we did, we completed most of our objective.

NARRATOR: The objective was made more dangerous

by the landscape of Normandy.

This farming region is known for its patchwork of small fields,

with fences formed out of a dense hedge of rocks and trees.

The plan was to land in the cover of darkness,

and those hedges would not be visible.

You couldn't see because it was dark.

NARRATOR: The gliders could carry 12 men or even a jeep,

land, and jump right into action.

If they landed safely.

These planes were made of wood and fabric

with a thin metal frame,

and would easily break apart if they hit an obstacle.

DON PATTON: It was terribly dangerous to fly a glider.

It was dark, it was overcast,

you were having to land into the little small fields.

I don't think anyone would want to be going 90 miles an hour

and crash into a tree with only plywood as a barrier.

NARRATOR: The commander for Allied air forces

predicted in a letter to General Eisenhower

that the gliders could suffer casualties

of up to 70% on D-Day.

The plan was to tow them across the English Channel

with C-47 planes just after midnight.

When they reached the drop zone, their tow rope would be cut.

Then the pilots had about three minutes before they had to land,

no matter what obstacles were in their way.

You're now traveling at about 80 miles an hour.

Now you make a turn, downwind.

And you've got three minutes

and the wheels are going to be on the ground.

Probably got three minutes of your life left.

NARRATOR: Swanson, now 94 years old,

says it was the last 30 feet of the descent

that was the most dangerous because you might hit a tree.

SWANSON: I must have been 20, 30 feet off the ground.

I didn't even see the tree.

And I hit the ground like that, and that took the wheels off.

And then you slid until you stopped

and everything got perfectly quiet.

And perfectly black.

And I said, "Anybody hurt?"

The guys behind me said, "Nobody back here."

And about that time, a cow bellowed real loud.

I said, "Now you know where you're at."

We were in the pasture.

NARRATOR: Once on the ground, these troops moved into position

to take the strategic targets.

What you're trying to do with these troops

is to prevent the Germans from counterattacking in your flanks

(gunshots)

before you've got enough combat power ashore

to repel these attacks.

NARRATOR: The glider operation went better than expected,

with less loss of life than predicted.

The troops took control of the strategic targets

without alerting the German command.

Along with the gliders,

13,000 paratroopers were dropped into France

with a mission to disrupt the German defenses.

These men were the very first Allied soldiers

to touch French soil on the morning of D-Day.

(gunshot)

Back at sea, the armada of ships was approaching the coastline

behind the minesweepers, with Robert Haga aboard.

Jim Booth and X-Craft crews were at work setting up the beacons.

The next obstacle was getting 150,000 troops on shore,

something that the Nazis had spent years

making sure would not happen.

LEWIS: Germans were good engineers.

They knew how to build bunkers, I tell you.

The thickness is from there to about here.

NARRATOR: Ever since invading Europe,

the Germans worked to build massive fortification

all along the north coast of Europe,

including 15,000 bunkers overlooking the beaches.

LEWIS: Just take a look at this.

You can see the entire beach,

and if you can see something, you can destroy it.

NARRATOR: At this point in the war,

the Germans knew their troops were stretched thin,

so defending their hold on the beaches

was essential to their strategy.

LEWIS: The defense is the strongest form of war.

If your defense is well done...

if you have enough obstacles,

enough mine fields, enough firepower...

.you can reduce the number of troops you need.

NARRATOR: Along the coast of France,

these bunkers held powerful guns that could shoot 20 miles.

And the beaches were covered with a series of mined obstacles

hidden just below high tide

that would destroy any ship that tried to land,

including the famous hedgehog: Crosses of steel

that could rip open the bottom of a ship.

All of this was part of one the most fearsome

military fortifications ever built.

It was known as Hitler's Atlantic Wall.

LEWIS: The Atlantic Wall was strong

and it was getting stronger day by day.

In the six months before June 6,

Hitler allowed almost unlimited resources to be thrown into it.

So it's pretty serious.

NARRATOR: One of Hitler's top generals, Field Marshall Erwin Rommel,

was sent to the front by Hitler himself

to fortify this powerful death trap.

The beach obstacles dictated a terrible choice to the Allies.

Do you land at high tide

so your soldiers spend less time on the beach

exposed to enemy fire,

or do you land at low tide

to protect the ships from these obstacles?

HENDRIX: Operation Overlord runs on the back of ships.

So the men are coming,

the tanks are coming, the supplies are coming,

and so it's important that the ships survive.

It's all to preserve the logistic ships,

because those are the irreplaceable items

of Operation Neptune.

Without them, Neptune fails.

NARRATOR: General Rommel knew that landing at high tide

would offer the shortest run to safety for the soldiers.

At tide high, these deadly defenses would be hidden.

But the decision had been made to land at low tide.

The ships would be protected from the deadly hedgehogs,

but how do you protect the soldiers?

The answer would come from an unlikely place...

a town better known for music than the military,

New Orleans.

Andrew Jackson Higgins was a colorful, local boat builder

who believed he had the solution for the Navy.

He already had a boat called the Eureka

that was built to navigate

the shallow waters of the Mississippi River...

not Rommel's deadly mines, but the logs and sandbars here.

So why not use them for beach landings?

The Navy was skeptical.

It seems Higgins didn't always follow military protocol.

JERRY STRAHAN: As the Depression was going on, business was bad,

and then he started building boats for rum runners.

Then he went to the Coast Guard and said,

"I don't know if you noticed it,

but the opposition has a lot better and quicker boats,"

and then he would build faster boats for the Coast Guard.

Then he would go back to the rum runner and say,

"The Coast Guard has newer vessels.

We need to build you something a little faster."

So he did play both sides of the fence.

NARRATOR: Today, at the National World War II Museum in New Orleans,

they're working to rebuild some of Higgins' famous boats.

Tom Czecanski, the chief curator at the museum,

is an expert in military hardware.

He says to understand what makes the Higgins boat work,

you have to look under one

to see the unique engineering of the hull.

CZECANSKI: The important thing here is that the hull

churns up the water at the front,

gets lots of air in it.

That's getting the boat up just that little bit more

that gets you on to the beach.

NARRATOR: At the back of the boat,

there was a specially designed metal structure

that ran below the propeller

to protect it when the boat ran aground.

Bring the boats on in, and damn the obstacles.

NARRATOR: The Eureka boat was designed

for unloading cargo over the sides of the boat,

like illegal liquor.

But the Navy's cargo of soldiers would need

to climb over the sides, making them vulnerable to enemy fire.

Was there a way to get the men out faster?

Naval engineers had seen Japanese boats

with front-loading ramps,

but no one knew how to build them.

And so they asked Higgins to draw up some plans.

STRAHAN: The Navy had been trying it for over two decades,

had been unsuccessful.

They wanted drawings.

Higgins said, "Drawings, hell.

You be here in three days and I'll have one in the water."

Which he did.

NARRATOR: Without a ramp, it took 57 seconds to unload troops.

With a ramp, it took only 19 seconds.

FILM NARRATOR: But they could land quicker,

exposed for a shorter time to enemy fire.

And with them, they could land their vehicles

for a fast mechanized assault.

Which saves you 38 seconds from being shot at on an open beach,

which saved incredible numbers of lives.

NARRATOR: Adolph Hitler knew of Higgins' famous boat

and is said to have called him "The New American Noah."

Not unexpectedly, the sonar operators are unable to find

any of these wooden boats.

It would have been difficult for them to survive

the strong currents of the English Channel for 70 years.

But there were many other landing craft made of metal,

which did survive, and they come in all shapes and sizes.

RALPH WILBANKS: All of these wrecks,

they're just out here and you don't know it.

If you could drain this, people would go,

"God, look at all of that," you know?

But you can't.

NARRATOR: In World War II,

there were dozens of different kinds of landing craft,

all engineered for specific tasks.

The famous Higgins boat carried soldiers, called personnel,

or possibly a jeep, so the boat was labeled

"landing craft vehicle, personnel," or LCVP.

There were landing crafts with powerful guns,

appropriately called "landing craft gun," or LCG.

The list went on:

LCI for infantry, LCM for mechanized, LCR for rockets.

And there was a whole class of larger ships,

like the LST, or landing ship, tank.

WILBANKS: I can't even imagine.

You know, we're sitting here looking at something,

trying to decide whether it's an ISM or an LST

or an LSVP.

I mean, there's massive amounts of LSs.

The guys that planned the logistics for this

were unbelievable.

NARRATOR: Today the sonar team sees the signal of an enormous ship,

longer than a football field.

All right.

NARRATOR: Even though the ship is buried beneath 100 feet of water,

this new multibeam sonar is accurate within half an inch.

Looks like it's busted up.

NARRATOR: Millions of sonar points are detected

and then translated into a three-dimensional image

that reveals intricate details of the engineering.

We'll go by it again.

NARRATOR: This level of visualization allows the team

to make precise measurements that help identify the ships.

Maybe the front door is here.

NARRATOR: They make out what looks like a bow door

and what the sonar team thinks is a vehicle

still on the ship's deck.

See that?

NARRATOR: These features help them identify the type of ship,

which they can cross-reference with a military manual.

The ship they've discovered today is an LST...

a landing ship, tank...

the workhorse of the Allied naval forces.

LSTs were some of the largest landing vessels in the fleet

and played an essential role in the D-Day invasion.

They addressed one of the biggest problems

created by the new amphibious landing strategy:

How do you get all the gear the Army needs onto the land?

LEWIS: One of the ways to look at an amphibious assault

is that it's a race.

The race starts the minute you hit the beach there,

and it's a race for buildup,

who can build up the most forces the fastest.

HENDRIX: World War II, tank warfare dominates,

and so you are bringing a lot of tanks across the channel.

They're not flown in, they can't drive there.

And so tanks, jeeps, other vehicles

all had to be brought by ships.

HEWITT: You didn't need a port to use an LST.

These are the chess pieces

that get moved around that global board.

And they are probably the single most important type of ship

used in assault landings

anywhere in the Second World War,

massively important piece of technology.

NARRATOR: The U.S. manufactured so many of these LSTs,

they didn't even bother to give each ship a name, just a number.

HENDRIX: These ships were built in the United States

and then sent to England, hundreds of them.

We had to change virtually every bridge on the Ohio River

and on the Mississippi to allow these combatant ships

to make it out to the ocean,

and we did it and we did it very rapidly.

One of the key elements in our technology

was our ability to build overwhelming numbers.

That production was an amazing factor

in our victory over Nazi Europe and Japan.

American production, American capacity to produce volumes

is what made the difference, you know?

We could produce 50 to their ten.

Eh, we win, you know?

NARRATOR: On the morning of D-Day,

these LSTs ferried men across the English Channel.

But they were too big to land

before the German defenses had been cleared.

That's where the Higgins boats came in.

HEWITT: In the early assault phases,

you don't want to put all your eggs in one basket.

You don't want to put a big, vulnerable ship on the beach,

so you have the famous Higgins boat

and the British equivalents,

which were small craft, capable of carrying 30 men,

who could get into action immediately.

And to be really crude about it,

if you lose one, it's not the end of your operation.

It's 30 guys, not 800.

NARRATOR: This landing chart shows

where the large ships like the LSTs pulled up

on the morning of D-Day, 11 miles off shore.

Then there are smaller paths into the beach

for the landing craft, like Higgins boats.

For Ralph Wilbanks, mapping these wrecks on the ocean floor

is more than just sonar science.

His father fought in the Pacific,

which makes these two-dimensional images

really come alive.

WILBANKS: These boats that are blown up

and pieces missing from them

and, you know, even one they dived on the other day

had big holes in it.

You could see where something happened violent

that caused that boat to go to the bottom,

which had to have been really... catastrophic

for the crew that was on the boat when it happened.

That's the reason they were the greatest generation.

MAN: It's very present to you even today?

Yeah, yeah, yeah.

Tough place.

NARRATOR: And as dawn broke on D-Day, it was about to get a lot tougher.

The massive fleet appeared just off the German beaches,

a scene made famous in the 1962 film The Longest Day.

If you've seen that classic scene in The Longest Day

when the German is in the pillbox.

HENDRIX: And the morning mist begins to lift

and then stretched out in front of him

from as far on the, you know, from the east

to as far on the west as he can see,

are ships, and they're emerging out of that fog.

Invasion.

It was the most massive naval force

that's ever been assembled.

NARRATOR: At 0530, it was time for the Allies

to bring out their biggest guns.

And the naval bombardment began.

HENDRIX: You have to imagine battleships

standing maybe a mile, two miles off shore.

ATKINSON: This is going to happen right around sunrise,

because you've got to be able to see what you're shooting at.

HENDRIX: So you are hurling these large bunker-penetrating projectiles

about the weight of a Volkswagen.

It's tremendously loud.

It's loud unlike anything that you can possibly imagine.

The smell...

The smell of cordite burning, of gunpowder burning

is something that you won't forget.

NARRATOR: The Air Force bombers also joined in.

ATKINSON: The Americans had made the decision

that they were going to have

a very truncated preparatory fire.

It only lasted 35 minutes.

If you were invading an island in the South Pacific,

sometimes the naval gunfire would last for days,

but because we were invading an area

where the enemy can reinforce quickly, the decision was made,

let's do it quickly, let's try and get on the beaches quickly.

The British preparatory fires lasted closer to two hours.

I think the British were right, as it turned out.

BILL ALLEN: The channel was full of boats.

The pillboxes were up on the cliffs

and they were firing continuously.

NARRATOR: Bill Allen was on an LST

bringing soldiers into Omaha Beach

and remembers this brutal start to the day.

I remember all the firing, the noise.

All the disasters, the death.

You'd see someone who had been killed floating on the water.

NARRATOR: Allen was a medic

with an overwhelmingly difficult assignment.

ALLEN: I was on the death detail.

Started bringing casualties out to us,

and we loaded casualties over the side of the ship.

By the time we would get them, they'd be dead.

But, uh, we'd clean them up the best we could,

identify them, to the fact... put the dog tags.

And you tried not to really dwell on it, I guess.

NARRATOR: Painful memories like these prevented Allen

from talking about his D-Day experiences until recently.

But today he has come back to Normandy

for the first time since 1944.

MAN: Welcome on board.

NARRATOR: He is once again on a ship off the coast of Normandy.

This time he isn't tending to casualties,

but instead he has brought his wife, Idalee, two daughters

and two of his grandchildren.

When I was here before,

everything was so confused and noisy.

Now it's so calm and peaceful,

it's hard to realize the difference between the two.

NARRATOR: Allen's LST delivered men into Omaha Beach

on the morning of D-Day.

Then, on their fourth trip into the beaches,

they hit a mine and the boat sank.

Today the sonar crew can show Bill just what happened to it.

Oh, look, here comes something.

There's the stern.

Boy, that is something!

CHARLES BRENNAN: I have been doing multibeam survey work

for over 25 years.

And when we had Bill, the veteran, on,

as soon as he saw that image,

his stories, his memories came back.

It was a way I had never seen multibeam data before.

Look at that big hole there.

You think that's from the mine, here?

Oh, as far as I know, it would almost have to be.

BRENNAN: Because he could see fully

the vessel that was blown out from under him on the sea floor.

You had a galley in here,

down below.

There's where we ate.

BRENNAN: It was the first time

I felt that the multibeam data had a soul.

NARRATOR: After 70 years of holding back his World War II memories,

Bill Allen, now at 88, is brave enough not only to return,

but to go down in the small submarine

to see the ship he was on when it sank.

Okay, Bill, I'm going to get in the sub first.

I'm going to get myself into the pilot seat.

We've got a ladder that we are going to drop down in.

Not to brag on him,

but I can't think of too many 88-year-old men

who would go down to... where they almost lost their lives

and revisit it and be excited about it like he is.

It's exciting.

I'm looking forward to it.

Okay.

HEWITT: One of the most important aspects of looking at this now

and not waiting any longer

is that we still have veterans with us.

We can still hear the testimony of those who were there

while we investigate the battlefield they fought on.

If we wait any longer, there simply won't be anyone left.

NARRATOR: The details of that horrific day slowly come back

during his dive with sonar expert Andy Sherrell.

Hard to believe, huh?

Oh, I tell you.

SHERRELL: Think we should go and try to find the bow?

Yeah, I'd like to see it.

I'd like to see it, too.

ALLEN: We made three trips in, successfully...

and started on our fourth trip.

How old were you?

I was just barely 19.

I had finished lunch, come out on the topside

and it was about 1:00.

I don't even know how to describe the noise that it made.

It sort of reminded me of when you step on a banana peel

and, you know, how you flip-flop

and expect to hit the ground sooner or later.

NARRATOR: LST 523 was sailing in rough waters

when it came down mid-ship directly on a German mine.

Allen was at the bow of the ship

in front of where the mine exploded.

ALLEN: It just blew the ship completely in half.

And it happened so quick?

Yeah.

A real state of panic.

Everyone began to jump off.

NARRATOR: On today's dive, Allen wants to see where that mine hit.

Looks like we're coming up on some debris here, Bill.

ALLEN: Uh-huh.

NARRATOR: And it doesn't take long before the expedition's submarine

is right on top of it.

Topside, we are on the wreck at this time. Over.

NARRATOR: This is all that remains of the LST 523,

a rusting hulk of metal

overgrown with barnacles and algae.

SUB PILOT: There's a tank.

Oh, yeah, look at that.

ALLEN: Oh, yeah.

NARRATOR: They can barely make out a tank on its surface.

SHERRELL: I bet you never thought you'd see that again.

ALLEN: No, uh-uh.

NARRATOR: The explosion tore through the ship,

and the bow that Allen was on was sinking.

Everyone began to jump off.

I knew I wasn't too good of a swimmer,

but I knew that something had to be done pretty quick

because our bow was going down.

What it boiled down to was which way I wanted to drown.

Did I want to go down with the bow

or did I want to drown swimming?

NARRATOR: Just at that moment,

Allen saw a life raft with a medic he knew from Mississippi.

ALLEN: And he hollered at me, he said, "You can't swim out here.

Stay there, I believe I can get in there to you."

He got within, oh, I guess 12, 15 feet of me,

and I said, "I can jump that far.

I know I can."

And I took off and made it.

We both just had one arm hung over the raft.

We picked up four more Army personnel.

NARRATOR: Allen and the others were saved

when a passing ship spotted their raft

and pulled them to safety.

ALLEN: Every time you close your eyes,

you're just reliving the same thing, a blast,

and seeing those same sights.

Sometime after midnight, I rolled over and Jack said,

"Bill, have you been asleep yet?"

I said, "Jack, I don't think I'll ever go to sleep."

NARRATOR: They say farewell to the 523.

SHERRELL: Ready to say farewell to 523?

ALLEN: Yeah.

On the ship we had a complement of 145.

The final count, 28 of us got off.

117 were killed or lost.

NARRATOR: For Bill Allen,

another powerful way to reflect on his time during D-Day

was taking his wife and family

to the American cemetery that overlooks Omaha Beach.

DAUGHTER: Daddy, what's the name you are looking for?

ALLEN: Stabile.

It's just never-ending.

NARRATOR: There are more than 9,000 American soldiers buried here.

One of them was Allen's commanding officer,

Vito Stabile.

There's Stabile, Bill.

Yeah?

That's him.

NARRATOR: A young doctor just out of medical school.

ALLEN: He was an officer

and the rest of us were enlisted men.

But we were all shipmates.

There wasn't that much distinction between us then.

Had a great life ahead of him, but it got stopped.

But I appreciate being able to come to his grave very much.

(bugle playing "Taps")

LEWIS: In World War II, 70 million people are killed.

70 million people.

It is the most significant event in the 20th century bar none.

Nothing comes close to it

in terms of shaping the world that we live in.

And so, when you stand at that cemetery,

these are the men who made the difference.

These are the men who did more to shape the world

that you live in right now

than anybody else, and you should understand that.

NARRATOR: The loss of life weighed heavily on D-Day planners.

Minimizing casualties was a solemn duty

and strategically essential.

One way to reduce casualties on the beach would be to make sure

the bunkers of the Atlantic Wall were taken out

before the infantry landed.

But doing so would prove to be

one of the biggest challenges on D-Day.

The naval and air force bombing just before the landings

were the first steps to dismantle the bunkers,

but then the guys on the beach also needed

to have the big firepower of tanks.

LEWIS: One of the attributes of a tank is firepower.

Main gun of a tank can destroy bunkers,

machine gun positions.

It could penetrate some of those concrete positions.

Small arms fire, even machine gun fire from infantry,

will not do that.

NARRATOR: The Allies had tried to put tanks in landing craft

at the battle for Dieppe,

but the process of unloading made them sitting ducks

and contributed to the slaughter.

So for D-Day the Allies needed to figure out

how to get the tanks to the beach quickly

without putting them in boats.

So the engineering question was, can you turn a tank into a boat?

Nicholas Straussler specialized

in engineering military equipment in England.

He had immigrated from Hungary, now under Nazi control.

Straussler took inspiration from the ancient Greeks.

Archimedes discovered that any object could float

if it displaced enough water

to offset the volume that's submerged.

Archimedes' principle was engineered

into Straussler's design by deploying an inflatable skirt

that came up on the sides of the tank about four feet.

It turned the tank into a rather poorly designed

but adequately floating boat, at least in calm waters.

You can see how Straussler pulled off his design

on this tank, retooled by Bob Gundy,

a military vehicle expert.

There is a framework made up of inflatable support tubes

that are then wrapped by a canvas skirt.

They were called duplex drive tanks, or DD tanks.

With the push of a lever,

the support tubes deflate and the skirt would drop.

So the tank was ready to roll into action.

These floating DD tanks were to hit the beaches

five minutes before the troops went ashore.

But on the morning of the invasion

the seas were dangerously rough,

with swells recorded at six feet high.

When the tanks off Omaha Beach were launched,

they immediately started to sink, wave after wave.

LEWIS: Let's say that you're one of these guys in a DD tank.

Put yourself in their place.

So four of them in the LCT.

First one goes off into the water

and immediately starts to sink

and the second one rolls off into the water

and starts to sink.

You're the third guy.

What are you going to do?

I don't know, I don't know.

You ask yourself why.

ATKINSON: It's pretty hard to understand 70 years later.

It was pretty hard to understand then.

These were their orders.

It was critical to get these tanks ashore.

Even though you saw that the guys in front of you

were having trouble, in some cases had gone under,

they kept pushing.

NARRATOR: There is a mystery about how many DD tanks

are still buried underwater.

The definitive answer will come

from the expedition's comprehensive sonar survey.

Once we close the hatch, the submersible is pressure-proof.

LEWIS: I am a retired soldier.

I spent 20 years in the Army,

but I haven't done much with the Navy.

Going down in the sub was a unique experience for me.

MAN: All right, Adrian, time to go.

All right, sounds good.

NARRATOR: Today Adrian Lewis and Andy Sherrell

are going down in the submarine off Omaha Beach

to investigate what happened to the DD tanks.

Sherrell has located a group of tanks not far apart.

SHERRELL: The bottom in sight.

The tank's over there.

NARRATOR: Two battalions of 32 DD tanks

were supposed to lead the way onto Omaha Beach.

Yeah, most of them are gone now.

NARRATOR: Without them the infantry would inevitably suffer

from an unrelenting German attack.

SHERRELL: Visibility, it's hard to see.

Got something straight ahead.

Oh, there we go.

You can see the main gun now.

Yeah, that's it.

That's nice, that's it.

NARRATOR: The water in the English Channel is so murky,

it is only with the help of sonar coordinates

that Sherrell and Lewis finally locate one of the lost DD tanks.

LEWIS: You don't see the skirt on it anymore, though.

SHERRELL: No, right around that edge, though.

LEWIS: Right, so that would have deteriorated, gone away.

When we first saw the DD tank, I didn't recognize it.

That's pretty cool, huh? Yeah.

NARRATOR: These swimming tanks were not engineered

for the six-foot swells they found on D-Day.

In all, 27 tanks sank off of Omaha Beach.

LEWIS: Looks like the hatch is open.

Yeah, one of the front hatches is open.

Which would make sense, so that they could get out.

LEWIS: My first thought is,

you know, the men in this tank, soldiers in this tank...

who they were, and did they get out?

Those tanks are burial places, essentially.

You have to keep that in mind.

NARRATOR: Despite the loss of tanks,

the Higgins boats full of soldiers arrived on the beaches

right on time.

But the battlefield they faced

was not what they were expecting.

(machine gun fire)

If you're an infantryman on Omaha Beach

at 7:30 in the morning,

you're really sorry you don't have more armor with you.

(heavy gunfire)

Because it's hell.

It's awful.

It's about as bad as combat can get.

And there are men by the dozens, then by the hundreds,

who are being slaughtered all around you.

And so, the fact that you don't have the protection

of a 33-ton Sherman tank next to you,

firing back at that pillbox over there

or firing at that machine gun nest over there,

all you've got is your rifle,

means that you've got a difficult row to hoe

for the next several hours.

NARRATOR: Combat engineers trained with explosives

to blow up beach obstacles like mines and hedgehogs

landed in the first wave.

ATKINSON: The job of those engineers was to blow gaps in these defenses.

They were to blow 12 gaps on Omaha Beach.

About half of all those combat engineers were killed,

wounded or missing.

NARRATOR: Along with the floating tanks, the plan had counted

on air force and naval bombings to take out the German bunkers.

But it did not work,

and so the men on the beach faced the Germans alone.

LEWIS: I've made the argument

the generals failed.

The generals failed.

The plan did not work at Omaha Beach.

This is why the cost was so high in terms of American lives,

in terms of numbers of soldiers killed,

because they had to generate the combat power necessary

to get over the bluff there at Omaha Beach.

ATKINSON: No, there was no failure.

In fact, the failure is entirely on the side of the Germans.

Omaha was a lot harder than they thought it was going to be,

but look, the Germans had four years

to build the Atlantic Wall.

It took less than four hours to crack the Atlantic Wall,

including at Omaha Beach.

Once those initial soldiers had scaled the bluffs

at the back of the beach, and they are up on the escarpment,

even though the war is not over,

the battle of Normandy has hardly been won,

the Atlantic Wall has been cracked.

NARRATOR: Wave after wave of infantry kept coming.

By 12:00 noon, after several hours of brutal fighting,

the first Americans had fought their way onto the bluffs

overlooking Omaha Beach.

The cost of that victory was very high.

Even today there is confusion among experts

as to the total casualties, with estimates ranging from 2,000

to more than 4,000 in the battle for Omaha.

The landings at the other four Allied beaches

went more smoothly with far fewer deaths,

although they were not without significant valor

and casualties.

It is argued that one reason things might have gone better

on the British beaches were a group of inventions

that the American Army decided not to use.

Ian Hammerton, a tank driver on Sword Beach,

still has the landing map from the hydrographic department

that he carried in his pocket on D-Day.

HAMMERTON: It suffered a bit

from seawater, but that was taken...

that's top secret.

NARRATOR: Hammerton's unit is famous because of its leader,

Major General Sir Percy Hobart.

HAMMERTON: He was an innovative character

who wouldn't take no for an answer.

NARRATOR: Hobart was known as a brilliant but eccentric character,

who Churchill specifically called back into service

for the preparation of D-Day.

His unit was known as Hobart's Circus.

HAMMERTON: Hobart's Circus, it was called,

because from time to time

all sorts of ideas were dreamed up for dealing with situations

and we acquired all sorts of strange equipment.

NARRATOR: Hobart's goal was

to engineer a way around the Nazis' deadly obstacles.

One of his most famous inventions was the flail tank,

used to clear mines.

HAMMERTON: This is a model

of a flail tank made by my son.

NARRATOR: Ian Hammerton, who piloted one of the flail tanks on D-Day,

shows how it worked.

It's an ordinary Sherman tank,

but it has this apparatus on the front.

The chains on the front would spin around on this drum

.

They're like this.

That's a part of a chain that got blown off.

The British actually have a more inventive approach

in some cases.

The Americans have the attitude,

"We don't really need those on our beaches.

It complicates our training."

And there's a bit of a "not invented here" quality to it.

Those are British gadgets; Let the British play with them.

NARRATOR: Hobart's engineers invented all sorts of clever ways

of overcoming the German obstacles,

which became known as Hobart's Funnies, though their purpose

was anything but that...

Flame throwers for incinerating

anyone inside the concrete bunkers;

Devices to fill anti-tank ditches

or create an instant bridge.

On June 6, Ian Hammerton's flail tank

did successfully break through the defenses at Sword Beach

and helped clear the terror mines.

Bill Allen's LST 523 unloaded men bound for Omaha Beach

in the morning,

and that afternoon they began to receive the casualties.

And Robert Haga, the minesweeper, kept working

to clear the lanes through the German underwater minefield.

By nightfall on June 6, 1944,

all five landing beaches were under Allied control.

Determining the exact cost in lives lost is difficult,

but it is estimated that there were at least 10,000 casualties,

including 2,500 deaths.

But more death and destruction was yet to come,

as the D-Day Expedition will reveal.

The goal of Operation Overlord, the D-Day invasion,

was not just to gain a foothold in Europe,

it was to secure all of Normandy

and ultimately drive through to Berlin.

Carver McGriff, who landed on the other U.S. beach, Utah,

says to understand the difficulty of fighting

in Normandy, you need to walk around the small farms

that lie just off the coast here.

Imagine you're a young second lieutenant

leading 25 kids like me

and your job is to take that next hedgerow.

What do you do?

NARRATOR: Despite all the years of planning for the invasion,

the Allies were not prepared for the obstacles they would face

in the battles here.

The problem was easy to overlook.

It was the ancient fences which surround farms in Normandy,

called hedgerows.

They seemed so unassuming.

One aerial photograph of eight square miles revealed

nearly 4,000 small fields.

There's a kind of terrain known as the hedgerow country.

This is fields that basically have turned

into mini fortresses.

The French have been farming that area for a millennium,

and every farmer has cleared his land

by pushing the rocks and debris and trees and whatnot

to the edges of his fields.

And consequently walls have been built around the fields.

McGRIFF: The hedgerows were a virtually perfect defensive way

for the Germans to fight the battle

and we had to find a way over them or around them.

LEWIS: There was so much focus, so much energy on getting ashore

that the follow-on tasks, the advance,

were not given the attention that they deserved

in terms of figuring out

how you need to break through this stuff.

NARRATOR: The battle for the hedgerows consumed the Allies

for much longer than expected.

By the time Normandy was securely under control

six weeks later,

another 200,000 Allied soldiers had been wounded or killed,

including McGriff's squad leader.

McGRIFF: He died while lying next to me.

In fact, he tried to talk to me

and then was not able.

It's a long time ago.

The memories don't hurt like they did for a while.

But they're always there.

ATKINSON: It's important not to think

that once June 6 turns into June 7

that somehow the war becomes less intense.

The fighting in the hedgerows is as awful, in some cases,

as anything that has occurred on Omaha Beach.

So the intensity that we see on June 6 is simply a foreshadowing

of what's going to come over the next three months in Normandy.

NARRATOR: So what did it take

for the Allies to win control of Normandy

in terms of men and supplies?

SYLVAIN PASCAUD: One of the things

that amazed us the most, I think,

was the amount of wrecks we found, the targets.

And we ended up finding 400 targets during our survey.

That's a lot of wrecks.

Can you look at the back of it?

NARRATOR: The most astounding revelation by the sonar experts

inside the Magic Star

is that the vast majority of those 400 wrecks

were sunk after D-Day,

revealing the extent of the enormous effort required

to reclaim Normandy.

HEWITT: The really exciting thing for me as a historian is

we can peel back the water and expose the playbook of Normandy,

just like assembling a huge jigsaw puzzle.

And it's just fascinating.

So we have evidence of when the troops went ashore,

and then we have evidence of the support phase

that took place for months afterwards.

All of that is there.

NARRATOR: Today, the divers have found

a barge carrying unusual crossbeam structures:

Components used to replace bombed-out bridges in France.

The barge was headed

to one of the most extraordinary engineering projects

of World War II...

something designed to make it possible to unload

all the necessary gear and men.

It was, in fact, a pet project

of British prime minister Winston Churchill.

In London, just down the street

from Churchill's wartime headquarters

is the Institution of Civil Engineers,

where evidence still exists of this ambitious plan.

These reams of detailed drawings all resulted

from a short, angry memo written by Churchill himself.

That memo got passed along to Tim Beckett's father, Allan,

a young military engineer.

TIM BECKETT: My father was working at the time

in the bridging department of the War Office.

Colonel Everall came to him with this memo and said to him,

"Beckett, you're a yachtsman.

See if you can make something out of this."

NARRATOR: The memo resulted from a disagreement

between President Roosevelt and Prime Minister Churchill

about possible locations for the invasion.

Churchill was worried that there was no port in Normandy,

so these landings could turn into another Dieppe.

His solution was as bold as it was daring.

If the Allies couldn't take a port by force,

then they would need to build one and take it with them.

BECKETT: It's astonishing,

the scale of it and the new organization required.

NARRATOR: Tim Beckett, a port engineer himself,

says the plan was astoundingly ambitious.

Certainly the engineering challenges were.

No one had ever conceived of building a portable port.

Any port must first provide shelter for ships

from the fury of the sea, and it must also have a way

to dock and unload the ships.

How could they engineer around the notoriously rough seas

and changing tides on the coast of France

and anchor a port onto the sandy beaches there?

Churchill didn't want to hear about the problems,

so he dashed off his short angry memo.

BECKETT: Churchill's memo is very famous.

It says: "Piers for use on beaches.

"They must float up and down with the tide.

"The anchor problem must be mastered.

"Let me have the best solution worked out.

"Don't argue the matter.

The difficulties will argue for themselves."

Well, I think you can read into that

that Churchill was pretty frustrated, shall we say,

when he wrote that.

It's a bit terse.

NARRATOR: The challenge of figuring out

how to solve these engineering problems fell, in part,

to the young Allan Beckett.

His initial idea was to build a road

that would float up and down with the changing tide.

The problem was basic physics.

How do you control the movement of a floating road

on a rough sea?

BECKETT: Most bridges have

typically four bearings,

and they like their bearings to stay

more or less where they are.

When you put a floating bridge on,

you've got a whole load of movements.

Obviously it's pitching, and going up and down, and rolling.

And then you've got all the load going on it as well.

Now, you either try and resist that

with a rigid structure, trying to hold it all together,

or you go with it.

NARRATOR: Beckett decided to go with it.

He designed a floating road

that consisted of pontoons sitting on the water

with roadways, like a bridge, spanning between them.

Another part of the design were massive structures

that are still visible today at low tide

off the coast of Normandy.

Like a jetty, these huge concrete blocks were used

to hold out the rough sea.

See the caissons that are submerged now?

NARRATOR: Seen on sonar, these structures make up

some of the largest wrecks off the coast here.

But to see what his father created,

Tim Beckett goes just outside of Paris

into the world of virtual reality.

MAN: I think you recognize this place?

I certainly do.

NARRATOR: A French engineering company called Dassault Systems

has recreated one of these artificial harbors in 3D.

We are walking along it, aren't we?

It's as if we could touch it.

NARRATOR: The code name of the project was Mulberry,

and so these were known as Mulberry harbors.

Two harbors were built: One for the Americans at Omaha Beach

and one British at the town of Arromanches.

This is really very good.

(chuckling)

Take your 3-D glasses and we'll jump into the 3-D.

NARRATOR: The basic design of the Mulberry harbors

was to create the needed breakwater

to block out the rough seas.

This was done in two steps.

First, old ships were sailed over from England

and then dynamited and sunk.

(explosion)

Next came concrete structures,

each the size of a five-story building.

They were built in England

and pulled across the English Channel.

These massive concrete blocks, called caissons,

created the jetty that held out the waves.

I think the floating roadways he was particularly proud of.

NARRATOR: Then came Alan Beckett's roadway that stretched from the beach

over floating pontoons to piers where ships could dock.

These roadways needed to be strong enough to carry

a 33-ton Sherman tank

and yet flexible enough to accommodate the water's motion.

Engineering around this was the key to Beckett's plan.

BECKETT: You can see that the pontoons are pitching and rolling.

And the bridges are following it.

The bridge spans are not rigid; They can go with the motion.

They do it by a rather clever detail.

Can we go underneath the bridge?

We've got a rigid connection on the central member here.

And all the other ones are pinned

and that allows the bridge to twist tortionally.

I always knew it was big, but I think this makes you feel

how big it is and how busy it was.

It was the busiest port in the world for a few weeks.

HENDRIX: There are such things as war-altering technologies

that once it's revealed that you have that capability,

it changes the face of battle.

To take an LST, a landing ship, tank,

and land it on the beach and put the ramp down,

it would take it ten to 12 hours to offload.

NARRATOR: That's because huge ships have to work around the tides,

and all of that takes time.

HENDRIX: When we established the Mulberry harbors,

where we put piers out,

we were able to offload a ship in one hour and 40 minutes.

NARRATOR: And all of this was anchored by a clever system

that held the roadways in place, designed by Alan Beckett.

Astonishingly, the first of two massive harbors were functional

in only three days after the landings.

But then not even two weeks after the harbors were built,

disaster struck.

One of the worst storms of the century blew down hard

on the coast of Normandy.

The American harbor at Omaha Beach was completely destroyed.

But despite being designed to last only three months,

the British Mulberry was in use for nearly ten,

during which time it became known as Port Winston

for the man whose angry memo got it built.

In all, two-and-a-half million men

and half a million vehicles

passed across these floating roadways.

They are just one of the many engineering feats

and innovations that helped the Allies prevail

in this crucial battle of Normandy.

The seas off the coast of France remained dangerous

for months after the landings.

The Germans still had control

of ports to the east and west of the landing beaches,

and so they could send in submarines

or drop mines from the air.

HEWITT: All it takes is one aircraft to fly through fast at night

and drop half a dozen pressure mines,

and your nice, safe passage area is suddenly lethal again.

This is quite well preserved.

NARRATOR: Today the Magic Star crew

has found a German U-boat submarine

that operated in the English Channel after the landings,

finally being sunk in July.

The German navy, of course,

put all its means it had available into the game.

NARRATOR: George Bigelow was an Army private headed to the front.

On Christmas Eve, six months after D-Day,

he boarded the Leopoldville,

a requisitioned cruise ship bound for France.

A German U-boat submarine lurking off the coast

torpedoed his ship.

It sank, killing nearly 800 men.

GEORGE BIGELOW: If you can imagine Coney Island full of people swimming,

that's just what it was like.

It was just horrible.

Guys were floating by

with their heads down.

You could tell they were dead.

Other guys were praying to their mother.

I couldn't talk about it for 20 years.

It was that bad.

NARRATOR: Today, Bigelow has joined the expedition

with his daughter Robin.

My father, George.

Enchanté.

Welcome on board.

Nice to meet you.

NARRATOR: Instead of going down in submarines,

they sent a robotic vehicle.

And George could watch the dive

on a video feed from the safety of the ship's cabin.

Looks like a porthole there, huh?

Yeah.

BIGELOW: Yes, it's a very, very humbling experience for me

to be able to see this.

The railing is just like the railing that I had a hold of

when I let go.

Right now I feel just very thankful and humble.

NARRATOR: When the Leopoldville sank,

Bigelow was thrown into the cold waters off of Normandy.

He was one of the lucky ones.

He was rescued and taken to a French hospital.

BIGELOW: They put me in bed,

and it's funny the things you remember,

because this nice-looking red-headed nurse,

she took her hand and brushed my hair back, just like that,

like my mother did when I was real young.

It was the most peaceful feeling

and it put me to sleep just like that.

HENDRIX: The decades are sliding by,

and we have fewer and fewer eyewitnesses.

And soon, the only eyewitnesses we'll have are these wrecks,

and they will still tell us their stories.

NARRATOR: The D-Day Expedition is providing new evidence

of the scale and difficulties of the Normandy invasion,

as well as helping to clarify the historical record.

By the time the Allies stopped landing on the beaches

in Normandy, months longer than ever planned,

millions of men and vital equipment had crossed here

and joined the battle to liberate Europe.

For the last 70 years, the cemetery overlooking Omaha Beach

has been the most powerful memorial

to the incredible battle here and the high cost of freedom.

Today the D-Day expedition is providing another way

to see and to honor this sacrifice.

I would make the argument for Americans

there is a cemetery that's underwater also.

Americans should be knowledgeable of that.

HENDRIX: The hidden battlefield of the tanks...

and the ships...

and the things that are scattered on the bottom

is a cemetery in and of itself.

There are literally hundreds of sailors and soldiers

that have their final rest in the waters that lie beneath.

And this is one of our most sacred charges.

NARRATOR: The sonar data collected on the expedition can now be used

to reveal this place that is, for so many, hallowed ground.

HENDRIX: It's important that we maintain them, that we respect them,

but that we also have this opportunity to examine them

for the story that they still have to tell to us.

NARRATOR: Perhaps the importance of the Normandy invasion

is best summed up by a story about General Eisenhower,

who asked to be reinstated in the Army

after serving as president of the United States.

HENDRIX: Why?

Because in Eisenhower's own words, "500 years from now,

"no one will remember that I was president of the United States,

"but they will always remember

that I commanded the troops at Normandy."

And when Eisenhower was carried to his grave

in Abilene, Kansas, in 1969, he went in an $80 soldier's coffin,

wearing a military uniform with only three ribbons...

the ribbons he earned at Normandy.

Captioned by Media Access Group at WGBH access.wgbh.org

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