Original subtitles

Today, on "Impossible engineering,"

The Harmony of the seas,

the largest cruise ship in the world.

The oasis class of ships is in a class of its own.

Nothing comes even close, in terms of size.

Topping every ship that came before it.

Orit took revolutionary engineering...

To make the impossible possible.

Captions by vitac www.Vitac.Com

captions paid for by Discovery communications

Royal Caribbean's oasis class cruise ships:

maritime einngeering at an unprecedented alsce.

Since 2009, they've held the title as the largest class

of passenger ships on the planet.

And, today, a third oasis-class vessel

is under construction:

The biggest one, yet.

Longer, wider, and heavier than any other that's come before it.

A lot of technology, engineering, and design

that has been put into this ship class is quite extraordinary.

It's simply mindboggling.

Nothing like the oasis class of ships has been built before.

This is in a class of its own.

The complexity of it is really, really staggering.

Sitting next to her

makes me feel like standing next to the skyscraper.

When it's finished,

the Harmony of the seas will be almost 8 times longer

than the statue of Liberty is high

and 2 times heavier

than the world's largest aircraft carrier.

Building a ship this big would be impossible

without some guidance from the engineers of the past.

Boats have fascinated humans whee!

For thousands of years.

Thank you.

The ancient Egyptians built vessels from reeds.

They were perfect for cruising the nile.

Oh, hello.

But their absorbent nature meant they didn't last.

Wood!

For centuries,

wood was the boatbuilding material of choice.

Warfare led to the use of metals, like iron.

Aah! Aah!

But iron is brittle and prone to rust.

Oh, man.

A new material was on the horizon.

Steel.

And it would go on to revolutionize the world.

In the chamber behind me,

there's about 150 tons of liquid molten steel.

The temperature is phenomenal.

It's about 1,650° celsius.

Steel is made by mixing iron

with various metals and elements.

Oh, my god!

The crucial starting point of the steelmaking process

is to remove the carbon and the other impurities.

And then, it's being poured into the ladle

and it'll go to the next stage,

which is to take it to the converter.

The steel is modified by adding extra alloys

and blowing in oxygen.

What's going on here is the very basics of steelmaking

and this wouldn't have been possible today

without the pioneering work of one engineer that's known

throughout the world by all material scientists.

For centuries, steelmaking was

an incredibly difficult and lengthy process.

That was, until the 1800s,

when inventor Henry Bessemer came up with a solution.

Traditionally, the wrought iron

was layered with charcoal and heated over days

and the charcoal would diffuse into the iron

and that would produce the steel qualities.

Very complex and difficult to achieve

and, therefore, very expensive, historically.

Bessemer developed a way to mass produce steel.

The Bessemer converter.

It's a huge, vast, cylindrical chamber, about 6 meters high

and it would've held 25 tons of steel.

The converter's capacity is impressive,

but its real ingenuity is in how fast it creates steel.

Bessemer discovered that pumping air into iron

accelerates combustion,

increasing carbon reduction and burning off impurities,

resulting in quality steel in a fraction of the time.

To show oxygen injection

really increases the combustion process,

I've got a simple demonstration here.

I've got a tray of charcoal.

With my thermal camera,

I can see the temperature of these coals at the moment

is around about 450° c,

so, now, what I'm gonna do is start to blow pure oxygen

onto these coals and see the effect.

Wow. Look at that.

The impact is amazingly impressive.

Ah!

So, if I now look at the temperature,

it's gone up to 1,000° c, a hugely dramatic increase

in the temperature of these coals.

So Bessemer had found a really amazing process

to reduce the carbon in steel.

Mass production of steel took off.

Its elasticity and strength made it a hot commodity

for railroad- and shipbuilders.

And, although processes have become

more sophisticated and complex,

it was thanks to that engineering genius

of sir Henry Bessemer and his revolutionary machine

that over 1.5 billion tons of steel

are now produced annually right across the globe.

The Harmony of the seas

needs a staggering amount of steel.

When finished, the ship will be longer than

5 football fields back-to-back and weigh over 227,000 tons.

Ssive steel sheets are delivered

to the assembly plant by train.

Automated systems cut the sheets

into thousands of individual components.

The steel panels, girders, and smaller components

are welded into modular sections called blocks.

Individual sections are joined together,

forming what are called grand blocks.

There are 90 grand blocks on the Harmony of the seas.

A custom-built gantry crane

lifts each grand block into the drydock.

The 90 blocks come together

ftoorm the world's largest passenger ship.

But how do

such gargantuan structures move across the open ocean?

Designing an engine for the Harmony of the seas

will be impossible, without some help

from the great engineers of the past.

The biggest cruise ship on the planet

is almost complete.

The Harmony of the seas

will be Royal Caribbean's third oasis-class ship.

It eclipses every ship that came before it.

Sitting as tall as tower bridge,

it's as long as five jumbo jets

and as wide as a soccer field.

When I really look at her, I'm amazed, always,

always, every single time, by the size of the ship.

It's big, but it's beautiful.

It's awesome.

You can definitely call this ship a small city.

It can house almost 9,000 passengers and crew on board.

It's a fully self-sufficient island, if you will.

The Harmony of the seas

is a miniature city, complete with theaters,

restaurants, bars, and other attractions.

How does such a gargantuan structure move

across the open ocean?

The engines are the heart of the ship

and the electrical network is the veins

to provide the power forward to the ship.

Without the engine, a ship is not alive.

Building an engine powerful enough

for this megaship would be impossible,

without help from one of history's great innovators.

The industrial revolution gave birth

to the steampowered engine.

It increased productivity, but enormous boilers were needed.

Oh! Help, please.

To get rid of boilers, engineers broke the mold,

burning fuel within a new engine.

Whoo-hoo!

Compressing gasoline and air and igniting it

with a spark plug to drive a piston,

the internal combustion engine was an industrial gamechanger.

But as the 19th century drew to a close,

an even greater innovation was just around the corner.

Mechanical engineer Henrik Birkegaard

has come to Copenhagen, in Denmark.

A city which owes a debt of gratitude

to an engineering marvel...

Which was inspired

by a truly remarkable innovator: Rudolf Diesel.

This is the HC Oersted power station in Copenhagen.

And, inside, you'll find a giant version

of Mr. Diesel's early engine concept,

which changed the face of the industry globally.

When it first powered up in 1933,

the diesel-powered HC Oersted

was the largest engine of its kind.

It's 40 feet tall and weighs 1,400 tons.

Back in the day, it could produce

a mindblowing 15 megawatts of power.

It's absolutely huge.

Standing next to this 3-, 4-story-tall engine

is very impressive.

The real power of this engineering colossus

comes from Rudolph Diesel's brilliant design,

patented in 1894.

It's very hard to believe that the inspiration

to this piece of engineering came from an object

which actually fits into the palm of your hand.

The internal combustion engine

had already made a huge global impact by the early 1900s,

but Rudolph Diesel's design made it even more efficient.

It doesn't need a spark plug, using only compression

to ignite the fuel, thanks to a double-acting piston.

This is a fire piston

and this little piece of kit was what inspired Rudolph Diesel

in his development of the Diesel engine.

And it works like this.

You have a small cylinder where you add a bit of cotton wool.

The cotton wool will work as fuel.

You have a little piston.

When you push down the piston here,

the air will be compressed, the temperature will increase,

and it will finally ignite the cotton wool.

And it goes something like this.

Compressing the air created heat,

the heat forced the cotton wool to burn, turning it into energy,

which forced the piston back up again.

The perpetual motion

within the compression ignition engine

works almost exactly the same way.

Air is drawn into the piston

and rapidly compressed, creating heat.

High-energy diesel fuel is then added, causing combustion.

This pushes the piston out,

to start the process all over again.

Unlike spark-ignition engines,

the continual firing of the diesel-fueled piston

creates superior power and effiencicy.

This means that you're able to burn

not only many different fuels, but also cheaper fuels,

compared to a spark plug, antique concept.

This ingenious piece of engineering was supersized,

creating the HC Oersted engine.

Incredibly, it still works,

more than 80 years after it was first fired up.

We're now about to ask Arthur to start up the engine,

the engine which was once the largest one in the world.

The HC Oersted's 8 giant cylinders

throw out more than 22,000 horsepower,

operating at around 75% efficiency,

compared to the 10% achieved by steam engines.

Basically, what you see here

haven't changed dramatically in almost 100 years.

Diesel's innovation

transformed the industrial world.

Its unrivaled power and fuel efficiency

made a huge impact on the world of shipping.

The launch of the first Diesel-powered liner in 1912

transformed the maritime world.

Cleaner and more compact than its steam-driven predecessors,

its engine was up to 3 times more efficient, increasing range

and opening up new trade and travel possibilities.

I ulwod say, within mechanical engineering,

it's the most important leap.

No doubt of that.

The HC Oersted may have been a monster, in its day,

but the Harmony of the seas's engines

are 6 times more powerful.

Fitting these massive engines inside the ship

is an engineering feat in its own right.

A team of nautical designers and engineers

have set themselves an extraordinary challenge:

Build the largest cruise ship in the world.

The Harmony of the seas

dwarfs anything that came before it.

When finished, it will be the largest passenger ship

on the planet.

The huge vessel is getting six Wartsila diesel engines,

the largest of which is almost 43 feet long

and weighs well over 200 tons.

Fitting them into the ship

was an engineering feat in its own right.

Now, we're in the main engine room of the ship

anwed are going to test Diesel number 1, this baby here.

This is one of the most exciting days of the boat.

Yo, eivel, let's start her up.

Without these supersized engines,

the Harmony of the seas won't make it out of the shipyard.

The starting of the main engine is one

of the main milestones on the shipbuilding project.

The enormous size of the Harmony of the seas

is allowing its designers to do something truly remarkable.

The sh hipas a split superstructure.

That means there's a vast, open space in the middle.

Its upper structure is impressive,

but, for the ship to be seaworthy,

it has to deliver beneath the waves, too.

So there are a few factors that are very important

for the fuel efficiency on the ship.

And, clearly, the biggest one is the hull shape.

The hull shape needs to be extremely well-designed,

so that you have a good, hydrodynamic shape.

So how do you design the perfect hull shape

for the largest passenger ship in the world?

It would be impossible, had it not been

for an innovative breakthrough made over 150 years ago.

Dr. Andrew Steele is in the British seaside town

of torquay, getting a taste of the power

behind a perfectly designed ship hull.

This is a phantom 19

offshore circuit-racing- class power boat

and it's built for one thing:

Speed.

The shape of the hull has been precisely matched

to the power of the engine and that means

that this thing can cut through the water

at incredible speeds,

in excess of 100 kilometers an hour.

This really is incredibly exciting.

The ability of this boat to cut through the water

would not be possible without the pioneering work

of one man here in the seaside town of torquay.

Over 200 years ago,

engines were transforming the maritime world,

but boatbuilders still had a lot to learn about ship design.

For centuries, shipbuilders had a kind of

one-size-fits-all notion about ship hulls.

There was one generic shape

that was considered the most efficient.

But there was no real way of testing this,

of working out how much drag, how much resistance,

a hull would encounter as it moved through the water.

In 1870, engineer William Froude

built a groundbreaking, hydrodynamic testing facility.

It was here, at his home in torquay,

that Froude built the world's first tow tank.

Froude's 250-foot-long water tank allowed him

to carry out precise tests at controlled speeds.

He mounted handcrafted models on a carriage,

then dragged them through the water

on a steam-driven pulley.

Froude's original tank, out there in the garden,

is, sadly, no longer in existence,

but we do have this lovely swimming pool

and, here, we're gngoi to try

to explain Froude's revolutionary discovery

and how it changed the world of shipping forever.

We've got three different-shaped hulls:

A flatfaced square box,

a slightly streamlined rubber duck,

and then this sleek speedboat.

After making sure each object is equally weighted,

Andrew tows the objects with a rope attached to a scale,

measuring the amount of hydrodynamic drag.

You can see this isn't slicing through the water.

It's sort of making a lot of turbulence.

If you look at the scales, 3, maybe even 4 kilos.

That's a lot of drag, a lot of restaisnce.

Next up, a slightly more streamlined rubber duck.

Well, that feels much lighter and the scales bear that out:

Maybe 1.5, 2 kilos of force there

and you can see the pool, much less disturbed.

There are far fewer of those Eddies.

The duck's just skimming across the top of the water.

But I still think we can do better.

Let's try the powerboat.

This is almost effortless, maybe 600 or 700 grams, tops.

You can see much, much less disturbance to the water.

The pool's almost still and, even from this scale model,

you can see why we make boats in this streamline shape.

The key to Froude's discovery lies

in a model's wake pattern.

Froud's real Eureka moment was when he realized

that he could use a lure to relate the drag

on a scale model of a boat to one that was full-size.

Froud developed a formula,

now known as the froud number.

That froud number can then be used

to compare a model ship to a full-size one.

By making sure they've got the same froud number,

you can work out how much drag the larger ship will experience,

work out how big an engine you need to install,

and it was this discovery that revolutionized

hydrodynamics and the shipbuilding industry.

Froud's hydrodynamic testing facility hosted

over 46,000 experiments.

His work paved the way for the hundreds

of state-of-the-art tanks in existence today,

many of which have been christened with water

from froud's original tank.

Engineers of the Harmony of the seas

are using huge, 30-foot models

to simulate a variety of sea conditions.

The result? A superefficient bow design,

a design that will be enhanced even further,

using a cutting-edge system known as air lubrication.

Micro bubbles create an air stream under the ship.

This cushioning effect significantly reduces friction

and the amount of power needed to propel the ship.

Air lubrication will increase

the Harmony of the seas's efficiency by 5%.

This colossal cruise ship may be streamlined underwater,

but above, its sheer stature poses a huge challenge.

It's got a sort of big wind profile on the ship.

It's almost like driving a skyscraper at the seas.

We have to be able to control her.

Engineers will have to look to the innovators of the past

for the solution.

In a shipyard in France,

the third addition to the largest class

of cruise ships ever built is almost ready.

The Harmony of the seas is a recordbreaker.

Designing a system that can control

such a huge ship in unpredictable weather

is a seemingly impossible challenge.

It's got a sort of big wind profile on the ship.

It's almost like driving a skyscraper at the seas.

We have to be able to control her

to the direct position what we want her to be in.

Their solution can be found

in an accidental discovery made nearly 180 years ago.

Naval architect Lucy Collins is on t ehenglish coast,

on a boat equipped with an innovation

that dominated shipping in the 19th century.

The paddle wheel.

Once the steam engine came along,

the paddle steamer was born

and it was unrivaled as the main form

of ship propulsion across rivers and the seas.

By the 1800s,

paddle-driven ships, like the SS Savannah,

had the ability to cross the Atlantic.

But it wasn't an efficient process.

So the paddles are on the side of the ship

and, as it goes over waves and, particularly,

in rough weather, the paddles are gonna start

coming out of the water on either side

and this is gonna reduce efficiency and speed.

Paddle steamers dominated the seas for decades,

but engineers were looking for a viable alternative.

Their inspiration came from an ancient invention.

For most of those early innovators,

the focus of their attention was this:

The Archimedes screw.

Dating back to the 3rd century bc,

this crank-operated contraption was used

to transfer low-lying water into irrigation ditches.

So we can see, if we turn the drill...

We start to get water transferring up the pipe

and then overspilling at the end of the pipe.

So inventors realized that they could apply this to a ship.

If you put the screw surface on the ship,

it can push the ship through the water.

In 1836,

engineer Francis Smith patented a revolving screw

that could be used to power a 6-ton ship.

But Smith accidentally snapped the 3-foot-long screw

during testing, leading him to a surprising discovery:

The shorter piece drastically increased the boat's speed.

It was the precursor to the modern-day propeller.

Even after his finding, the Navy believed

that paddle power was the future.

Adamant about the advantages of his design,

Smith decided he needed to prove his doubters wrong.

He decided to pit his screw-driven SS Rattler ship

against the paddle-driven SS Alecto

in a tug of war and a race.

Both ships weighed the same and had identical engines.

Smith's lifelong work was on the line.

Today, Lucy is recreating this famous event.

She's taking on a propeller-powered bike

in her paddle-powered vessel.

So the paddle wheel's got quite a good acceleration

straight from the start.

But, it seems like the propeller blade

is just reaching its full efficiency.

And, unfortunately, the paddle wheel just can't keep up.

The paddle wheels are slipping

and it seems like the race is lost.

Smith's screw-driven vessel

blew its paddle-powered opposition out of the water,

ushering in a new chapter in propulsion.

That was the start of the propeller

being the primary means of propulsion for ships

from then until now, almost 180 years later.

In order to drive the largest cruise ship

in the world, the opprellers

on the harmonofy the seas need to be of epic proportions.

Each of its 3 bronze propellers are 20 feet wide

and weigh almost 45 tons.

T buthe designers of this megaship

can't just make it go fast.

They need it to have the ability to maneuver through small ports.

The Harmony of the seas,

the largest cruise ship in the world.

Three massive, bronze propellers

move this behemoth through the open seas

quickly and effiencitly.

But this megaship can't just go fast.

It has to be able to maneuver in and out of port.

Their solution lies with an invention developed

in the 1950s by German engineer Josef Becker.

He designed something called the rudderpropeller.

His propeller could both move and steer the ship.

It was revolutionary in its design.

The modern incarnation of Becker's concept

is being installed on the Harmony of the seas.

It's called a potted propulsion system.

The three pods act like airplane propellers,

pulling the ship through the water, rather than pushing.

Utilizing 5.5-kilowatt bow thrusters,

they allow the captain's unparalleled control.

The pods can be turned in an instant,

getting the vessel into locations

that were previously off-limits to megaships.

As the Harmony of the seas's

inaugural voyage draws closer,

making sure the ride will be comfortable

for all 6,000 passengers is a top priority.

The clearest issue we have is that the ship is not stationary.

It moves. It rolls. It heaves.

There's all kinds of movements and acceleration on the ship,

which makes it a little bit more complicated.

How do you keep such an immense vessestl eady,

in even the roughest seas?

This is a gyroscope.

And, to explain how it works, we're gonna need one of these.

A motorcycle's wheels do more

than just power and steer it.

A gyroscope works

by conservation of angular momentum, which means that,

when it's spinning around very, very quickly,

it doesn't wanna change the direction of that SPiN,

and this can give some pretty counterintuitive effects.

These physical reactions can be extraordinary,

an effect known as ghost riding sometimes occurs

when a bike crashes and loses its rider,

but then rights itself and continues its journey.

This phenomenal sight comes down to gyroscopic forces

acting on the bike

as it tries to maintain its original orientation.

So how does it work? Aah!

Well, I'm gonna try and show you

with this piece of apparatus here.

What we've got is an ordinary bike wheel,

but we've filled the inner tube with concrete,

just to make sure it's nice and heavy.

So, currently, this thing isn't spinning,

and that means it hasn't got any angular momentum.

And that means it's pretty easy just to make it SPiN around.

It's not very stable.

However, if we get this electric drill

and get the bike wheel spinning

and as we add more speed to t dherill,

we're increasing the angular momentum.

Now, it's moving very fast and, now, if I give it a whack...

You can see this thing is stabilized.

And that's why, in extreme circumstances,

a wheel can refuse to lie down.

It's the stabilizing effect of a gyroscope

that maritime engineers are interested in.

If I get it spinning nice and quickly,

I can just balance the spinning wheel on my hand.

Gyroscopes can do this for a ship.

In 1917, American inventor Elmer Sperry

took advantage of gyroscopic forces

for the first time in a large vessel.

He equipped the USS Henderson with two enormous gyro wheels.

Each wheel weighed 60 tons.

Inside, 10-foot flywheels spun

at an incredible 1,100 revs per minute,

creating huge amounts of angular momentum

in order to minimize the ship's roll.

It was a huge engineering breakthrough.

But his brute force approach was impractical.

As technology has developed, so has the use of gyroscopes.

Over the years, pioneering scientists

and engineers have experimented with these gyroscopic forces

to the point where, nowadays, we can fit tiny gyroscopes

on the surface of a computer chip, like this one.

And they're used everywhere,

from mobile phones to aircraft, and even ships.

The Harmony of the seas

takes the magic of the gyroscope into the 21st century.

Instead of using giant, spinning wheels

like those employed on the USS Henderson,

the Harmony of the seas uses a small gyroscope as a sensor,

which controls mechanical stabilizers via computer.

So, in rough seas, what we can use to minimize

the roll and the movement of the ship are stabilizer fins

and they are actually fins that emerge laterally

from the ship's hull.

This is the location we are in now.

And what it does:

It's sort of like a wing that comes out of the ship.

It emerges laterally, like this,

and then it turns around its axis.

A stabilizer blade is recessed

into each side of the ship.

They're deployed when seas get rough.

Stabilizer mostly counteracts the roll,

so, the sideways movement of the ship.

So if the gyroscope feels the ship starts moving this way,

it asks the fin to exert force

so that it counteracts the movement here,

so it tries to always right the ship.

It's been a century

since the first cruise ship set sail on the world's oceans.

Now, by drawing on the innovators of the past...

standing next to this 3-, 4-story-tall engine,

it's very impressive.

Adapting their ideas, honing them,

and making trailblazing innovations of their own,

the engineers, designers, and workers constructing

the Harmony of the seas are making history.

When first these plans were thought of,

I'm sure there were a lot of people who thought

that we were absolutely nuts, absolutely crazy,

to think of even building a ship this large,

but, you know, we are not afraid to think large, think big,

think outside of the box, and that's what you need.

You need a little bit crazy thinking, at times,

to really make great things.

They've succeeded in making the impossible

possible.

When we started this project, more than 2 years ago,

we had only design on the paper.

But as we now see it, the dream come true,

I feel really proud of what we have achieved.

Repair and Synchronization by Easy Subtitles Synchronizer 1.0.0.0