Today on "Impossible Engineering"...
The littoral combat ships, the U.S. Navy's
fastest combat vessels.
If you're a pirate or you're a drug runner
and you see that ship coming towards ya,
it's time to shut down your engines
and put up your hands.
To create a vessel in a class all its own.
She's basically one of a kind as far as warships goes.
I am sailing a ship that's unprecedented.
Engineers had to turn to the pioneering
innovations of the past.
Here we go.
Yes!
If these engines were to cut out,
this boat would be in serious trouble.
Oh, ho, ho! This is really incredible.
What an amazing airplane.
That made the impossible possible.
... Captions by vitac... www.Vitac.Com
captions paid for by discovery communications
the U.S. Navy has the largest sea force on the planet.
Throughout its over 240-year history,
its ships have carried out operations
in the deep blue waters of the world's oceans.
But today the Navy's assignments are evolving.
Gone are the days of open-water blue Navy battles.
Many of the places where we need to be as a Navy
are in coastal regions.
To combat problems such as piracy,
people-trafficking, and aid distribution,
the fleet must operate in shallow coastal waters,
known as the littorals.
To navigate waters close to the shore,
shipbuilding program manager captain Tom Anderson
had to construct a particular type of ship.
To operate effectively in the littorals...
We need a high-speed ship, and it's gotta be adaptable.
It's gotta be capable of doing multiple missions.
That's our challenge.
It's a challenge that chief engineer
lieutenant Damon Gilbert also had to overcome.
The ideal ship for this environment
would be a ship that's light,
a ship that has a very shallow draft,
and a ship that can handle itself
and move very quickly.
The solution...
The littoral combat ship class.
Made up of both the mono-hull freedom variant
and the trimaran independence variant,
this revolutionary class of ship
is at the vanguard of marine engineering.
This is gonna change the face of how we operate inside
those waters for years to come.
Built for speed,
both the freedom variant semi-plaining hull
and the independence variant's trimaran design
create ultra hydrodynamic efficiency.
Using lightweight aluminum, powered by an innovative
propulsion system,
each ship can travel over 45 miles per hour
in only 14 feet of water.
It's capable of being reconfigured
for multiple missions,
and it's able to deploy smaller boats.
A vast helicopter pad also extends the crew's reach.
But to produce a high-performance,
fast-moving fleet for shallow waters,
the ship's designers had to create
the most effective propulsion system.
The problem was standard propeller systems
significantly push the ship below the water line
and require much deeper waters.
If you want to chase down a ship
or you want to elude another vessel
to get out of danger, you want to be able
to maneuver as quickly as possible.
So how do you propel a ship this fast
in near swimming-pool depths?
This would not have been possible
without a breakthrough innovation from the past.
Humans have always needed to navigate
the world's shallow waterways.
Initially, we used arm power to paddle.
It was effective, but tiring.
Arg!
Out of the way!
Oh!
The vikings added a sail to conquer the coastlines.
This worked well, but... Huh?
Only when there was wind.
Gah! for Odin's sake!
With its small draft, the paddle steamer seemed to be the answer.
Well, I do declare... vikings!
But they had significant problems.
Oh, my!
In the 1940s, the introduction of air boats
brought high-speed travel to the everglades.
Whee!
Oh, no!
Whoa!
But a better system was needed.
Show-off!
In the Grand Canyon, mechanical engineer Dan Dickrell
is riding upstream on the Colorado river
to reveal one of history's great engineering achievements.
The beautiful noise you hear
right now is two 550-horsepower
8.3-liter engines pushing this 20-ton boat
up these crazy, crazy rapids.
If these engines were to cut out,
this boat would be in serious, serious trouble.
But the key to driving against the current
isn't in the engines.
It's due to a pioneering propulsion system.
Getting to places where others can't,
in extremely shallow water,
was born out of the imagination
of someone whose childhood desire
was to challenge the rapids
and go where no one else could.
To do this, New Zealand-born
inventor William Hamilton
needed to overcome the limitations
of standard motorboats.
Now, Hamilton had a problem with this.
Because the waters he wanted to to go on were too shallow.
Huge rocks would effectively wreck this crude propeller.
So Hamilton got rid of the propeller altogether.
In 1954, he commissioned a plywood boat
and attached a centrifugal pump to its engine,
creating a unique water-driven jet propulsion system.
How the Hamilton jet motor functions
is around the middle of the boat,
there's an intake that brings water in
from whatever body of water the vessel is navigating.
Hamilton's uses an impeller that's spinning very fast
to greatly accelerate this stream of water.
That water is highly turbulent and twisty.
And so the Hamilton passes the water through a series
of stator vanes, creating a uniform,
but high-velocity jet.
And in 1960, Hamilton tested his bold
water jet design at the Grand Canyon.
Hamilton vowed to be the first to take a vessel up
a 160 kilometer section of this
notoriously unnavigable Colorado river.
Now, it may look calm right here, but upriver,
the rapids are crazy.
He traveled against the current,
including the notorious Vulcan rapids in just nine days.
With his son John at the helm, Hamilton made history
and conquered the mighty river.
- Whoo! - almost 60 years later,
Hamilton's water jet's sheer power...
This acceleration is intense.
...And its ability to navigate shallow waters
with the added benefit
of mind-blowing maneuverability... Here we go!
Yes!
...Continues to open up new waters.
Whoo!
Thanks to this spectacular demonstration
of man versus rapids, this unique propulsion system
was embraced across the planet.
All right, let's go!
The ships' engineers have super-sized
Hamilton's water jet innovation
to create a revolutionary propulsion system,
capable of going 45 miles per hour in shallow waters.
The way that this ship achieves that speed is through the use
of two gas turbines and two diesel engines
that drive a propulsion train
that is propelled by water jets.
At Austal U.S.A.'s shipyard in mobile, Alabama,
the latest independence variant, u.S.S. Tulsa,
is having her jets inspected
and getting ready for launch.
When this ship is going full power,
there's roughly 24,000 gallons
per second passing through these four water jets,
which equates to the ability
to fill two Olympic-sized swimming pools
in less than a minute.
Not only do these massive jets
generate colossal power, they also act as a rudder.
Each water jet is capable of independently being steered,
which allows for a lot of flexibility and maneuverability.
Like Hamilton's water jet system,
water goes through four mighty impellers
and discharges at high velocity.
To steer, each jet's water flow is deflected
by a rotating nozzle,
enabling fast, agile maneuvers.
And to reverse, buckets pivot over the exit nozzles,
forcing the jet flow backwards.
Built into the hull, these massive ships
can operate in just 14 feet of water.
300 yards, turn.
Next course... 309.
Off the California coast,
commander Mark Stefanik is harnessing
this incredible power aboard the u.S.S. Montgomery.
The water jet system allows me to turn and maneuver the ship
with much more fidelity
and a great deal more responsiveness
than a traditional ship.
So by creating opposite forces on either side of the ship,
I can actually turn the ship almost on its own axis.
I can twist the ship in a perfect circle
because of the amount of control I have through the water jets.
The 100,000-horsepower propulsion moves this massive
ship over 45 miles per hour.
This is actually our full capacity right now.
You can tell there's quite a bit of turbulence back there.
And this vessel can practically stop on a dime.
I've pulled the ship to stern and go from full speed to zero.
It's a very, very smooth transition.
The entire ship just basically will stop in the water
within less than a minute.
By using water jet propulsion,
at 29 horsepower per ton,
compared to an aircraft carrier's
three horsepower per ton,
these combat ships are the most efficient
in the U.S. Navy.
It's basically like driving a jet ski.
This ship could actually maneuver sideways.
It could pivot itself by standing still.
That's something totally different
from any other warship out there.
This propulsion system is unrivaled.
But to be truly trailblazing,
the designers of these incredible ships
must overcome more hurdles
and turn to the innovations from the past.
To make the impossible possible.
The littoral combat ships.
These are the fastest and most agile combat ships
in the U.S. Navy.
And program manager, captain Tom Anderson,
believes they are unstoppable.
If you're a pirate or you're a drug runner
and you see that ship coming towards ya,
it's time to shut down your engines
and put up your hands.
But to operate fully armed and at full speed
without getting beached in shallow waters,
the ships must also be exceptionally light.
Every pound that goes into this ship is assessed,
because every pound that goes into this ship
is an increase in its draft
and a decrease in its speed.
And u.S.S. Freedom's chief engineer,
lieutenant Damon Gilbert,
had to strike the right balance.
The difficulty we find with the older ship designs
is the steel hull with the steel superstructure
makes the ship incredibly heavy.
The less weight we have equals a smaller draft.
Smaller draft equals a longer sustainability
without worrying about running aground,
without worrying about getting into situations
that we can't come back out of.
So how do you build a lightweight combat ship
without compromising on strength or size?
To resolve this conundrum,
the engineers looked to the past.
Humanity has always strived to find the perfect material
to stay afloat.
The Tamil fisherman of south Asia
only need a log under each arm.
Come here!
But when partially submerged, there was a catch.
Yow!
In the 9th century B.C.,
Assyrian soldiers lied on inflatable goat skins
to sneak up on the enemy.
Uh-oh.
Although they were lightweight...
The skins were vulnerable.
Oof! uh, hello.
And push.
For some, Clay was a cheap alternative.
A row of pots could buoy a raft easily.
Steady.
Look out!
Oh!
But avoiding the rocks wasn't always possible.
Oh, no!
Shipbuilders needed a more durable material.
Engineer Dan Dickrell is in Tulsa, Oklahoma,
unveiling a game-changing marvel
that sparked both a naval and aviation revolution.
Oh, wow! What a beautiful airplane.
Such an engineering icon.
This is the DC-3 flagship Detroit.
She was constructed 80 years ago,
the oldest flying DC-3 in the world.
Prior to this stunning machine,
most planes were made of wood.
Although lightweight, wood broke easily.
And in 1931, a Fokker F.10
lost an entire wing, crashing into the Kansas prairie,
killing all eight people on board.
As America reeled, wood-frame construction ceased,
and engineers had to turn to metal.
But this transition was only possible
because of a chance discovery
by German metallurgist Alfred Wilm.
Different metals also had different weights between them.
Here we have aluminum, and here we have steel.
For the same size, steel weighs about three times as much.
Because of aluminum's relative light weight,
it seems like the ideal material
to construct aircraft from.
The problem was 100 years ago, it just wasn't strong enough.
To strengthen it, Alfred Wilm experimented
with aluminum's chemical makeup.
He introduced different metals...
manganese, magnesium, and copper...
in different ratios to create an alloy.
He heated it to high temperatures then quenched it.
He repeated this process over and over again.
Unfortunately...
The aluminum was still very bendable.
Wilm gave up.
But when he returned to the lab a few days later,
something extraordinary had happened,
something so transformative
it would go on to revolutionize
military hardware across the planet.
It was very strong and quite literally changed
the face of aviation.
Making this impossible warship possible.
The littoral combat ships are the fastest
in the U.S. Navy.
But building attack vessels that are light enough
to navigate shallow waters
without compromising on speed
or size relies on a revolutionary discovery.
After experimenting with an aluminum alloy and giving up,
metallurgist Alfred Wilm discovered
something completely unexpected a few days later.
The aluminum... Had age-hardened.
It was much, much stronger.
Wilm's introduction of new metals chemically altered
the aluminum's soft crystals, and, over time,
new minute crystals had grown within
each one of the aluminum crystals,
reinforcing the overall structure.
Wilm called this new material duraluminium.
It was very strong,
and quite literally changed the face of aviation.
The new alloy became known as the winged metal,
and 80 years after its construction,
this iconic all-aluminum DC-3
is taking to the skies once more.
First launched in 1935, the lightweight DC-3s
became the world's first
commercially successful passenger planes.
Taking inspiration from aerospace,
L.c.s. freedom variant engineers have used high-grade aluminum
to create some of the lightest combat ships
of this size ever built.
The actual hull itself is steel, where the superstructure
or what we like to call sometimes the house
where people live and where all the facilities
are is actually comprised of aluminum,
thus saving literally tons of weight,
which has a direct effect on the draft.
Despite the freedom variant being 387 feet long
and 57 feet wide
and with a steel hull and aluminum superstructure,
the ship weights a comparatively light 4,000 tons
with a draft of only 14 feet.
But engineers on the independence variant
have gone one big step further.
So the "L" in L.C.S. Doesn't stand for little.
This ship is the largest all-aluminum vessel
operating on the seas today.
While constructing these trimaran mega-ships
in Austal U.S.A.'s Alabama shipyard,
at 415 feet long and a colossal 100 feet wide,
every pound counts.
Aluminum has great strength-to-weight ratio.
It's a third of the density of steel.
And for the volume of ship we're building here,
aluminum structure was the only way
for us to meet speed, range,
and draft requirements.
Taking Alfred Wilm's approach to the next level,
engineers have adjusted the aluminum recipe,
preparing the ship for salty waters.
Aluminum alloys that we used in construction of this ship
have good corrosive properties,
which means, unlike other Navy ships
where exposed steel needs to be painted,
this ship is not painted above the water line.
That saves us money and it also reduces the weight of the ship.
This weight reduction helped decrease the independence
variant's draft to a mere 14 feet.
And that enables us to go into waters and visit ports
that traditionally our Navy ships
have not been able to get into.
The designers of these revolutionary ships
are pushing the limits of marine engineering,
but to effectively carry out multiple missions,
they had to draw on more innovations from the past...
Here I am, aboard the ray gun.
This can manage speeds of up to 28 miles an hour.
...To make the impossible possible.
The littoral combat ship,
built to patrol the shallow coastal waters
called the littorals.
Program manager Tom Anderson has helped take
the U.S. Navy's fastest combat ships to a whole new level.
Operating in the shallows require high-speed ships
with shallow drafts.
The answer to those challenges is the littoral combat ship.
Made up of the mono-hulled freedom variant
and the trimaran independence variant,
the L.C.S.'S power-to-weight ratio
is more than double that of a typical destroyer,
and there's a reason the ships need such flexibility.
We need to have a ship that's capable of doing
multiple missions,
whether it's searching for submarines,
finding minefields and detonating those mines...
all these things are required for the future Navy.
But to be truly adaptable,
not only must these ships carry equipment
for multiple assignments,
they must also provide an effective platform
for air-based missions.
We're conducting helicopter operations.
Their are limitations as far as how much pitch
and roll a ship can have based on the weather and environments
in order to conduct those helicopter operations.
So how do you marry the performance of a speed boat
with the volume and stability of of an aircraft carrier?
To solve this seemingly impossible problem,
the U.S. Navy's designers had to seek
more inspiration from the past.
Off the south coast of England,
science communicator Kate Mulcahy
is investigating the origins of one of the fastest,
but most stable sailing vessels ever built.
Here I am, aboard the ray gun.
This is a 24-foot boat that can still manage
speeds of up to 28 miles an hour.
It has not one, but three hulls that are designed to cut
through the water to provide minimum resistance.
In 1946, Ukrainian engineer Victor Tchetchet
unveiled this trailblazing shape
at Marblehead race week in Massachusetts,
calling it a trimaran.
Although revolutionary in the yacht-racing world,
his design was inspired by pacific islanders
looking to improve the humble canoe.
You can still see why this design has endured
for so many years.
It's thin and long, which means
it moves easily through the water.
Also, it doesn't have a keel,
so it sits quite high in the water.
That means it's perfect for exploring shallow,
narrow waterways.
Despite all of this, it can only go as fast as I
or anyone can paddle in it,
which means its speed is limited.
Secondly, as you can see, it's not very stable.
So imagine this out on the open water
contending against waves.
So if I was to try and get in this...
If I try and... oh!
I don't even think... It would be possible...
Oh! ...without it capsizing.
So not ideal.
To island-hop across the open ocean,
the pacific islanders needed a new design.
And what they came up with was this.
This is the same long fin, central hull,
but with two outriggers lashed parallel on either side.
Now, when we were making this, we used plastic tubing,
but they would have been using just logs.
The addition of outriggers
instantly transformed this simple canoe.
So you can see this boat is much more stable.
It's practically impossible to capsize it.
The addition of the outriggers has increased the stability
and also increased the buoyancy.
That means that it sits higher up in the water
and means it's easier to explore the shallows.
And, finally, allowed me to add a sail,
so no more paddling for me.
With these clever additions, islanders
could access countless islands
throughout the pacific ocean.
Improving on the ideas of the islanders,
Tchetchet used the wide stable base to create
a gracious spread of sail.
He also streamlined the light, buoyant hulls so they cut
through the water and created minimal drag.
All of this is what makes the trimaran
as one of the fastest class
of sailing boat in the world today.
Employing a trimaran on a yacht is one thing,
but integrating this design onto a 4,000-ton
combat ship is quite another.
Trimarans are really important
when you're doing surface warfare type events.
To super-size this technology,
the Navy's engineers
had to make the impossible possible.
The littoral combat ships
are the U.S. Navy's fastest warships.
To achieve maritime speeds of 45 miles per hour,
engineers super-sized the principles
behind Tchetchet's racing yacht
to create the Navy's first
high-performance trimaran combat ship.
And at Austal U.S.A.'s shipyard in Alabama,
the u.S.S. Tulsa is receiving its finishing touches.
You see it has a very fine-tuned bow, designed to Pierce waves.
As we go further back, you see the hull widen.
And just here to the right, you can see the outrigger.
And, again, just like those canoes with the outriggers,
which give us that added stability,
we get high speed.
The stabilized central hull
with two outriggers moves the ship
displacement point upwards.
This reduces drag, allowing the ship
to reach speeds of over 45 miles per hour.
Additionally, the ship's vast width allows
for an 11,000-square-foot flight deck,
and the vessel can accommodate smaller boats below,
extending its capabilities across the world's oceans.
Trimarans are stabile platforms, and those are really important
when you're doing things like operating helicopters,
launching vehicles,
and conducting high-speed maneuvers
when you're doing surface warfare type events.
At sea level, this unique engineering is clear.
You get a really good perspective of just
how wide the ship is
and how that trimaran design provides for stability.
Commander Douglas Meagher is traveling
between its outriggers, also known as amas.
We've got over 200 feet worth of ama tunnel here.
Were as the ship transits through the water at high speed,
you get the very slender main body hull,
and you have this ama that's cutting the water
and maintaining the ship's stability
at 40-plus knots.
Any other ship in the Navy,
you're not gonna be underneath the main
hull form of the ship like this.
This is a one-of-a-kind design.
In its home port of San Diego, California,
both the freedom and independence
variants of these combat ships
are changing the face of nautical design.
The littoral combat ships allow us
to operate at high speeds in shallow water
with stability unmatched by
any other naval ship of this size.
And now commander Mark Stefanik
is setting off in the u.S.S. Montgomery
to patrol the California coast.
Well, he is definitely cutting the channel.
Let's give him the five short.
Five short.
But in these busy waters,
unforeseen hazards lurk everywhere.
Got a jet ski off the port side, 350 headed forward aft.
All right, I think we have a good shot
at taking them down our starboard side.
- 60 yards, right? - All right, steady as she goes.
Steady as she goes, 178.
So there's a number of sailboats that we had to maneuver for,
as well as some other small craft.
So that did add to the complexity of the ship
trying to get underway.
Crowded coastal waters are just the start.
Out in the open ocean, it's pretty easy to determine
what kind of traffic you're gonna deal with,
'cause there's very little of it.
When you're in a littoral environment,
you're operating in the vicinity
of very dense commercial traffic.
But in more hostile shallow waters,
determining friend from foe
can be the difference between life and death.
Nothing is more critical to the captain,
the decision to either engage
or not engage a potential adversary.
So how do you identify an enemy in a split second
in some of the world's busiest seas?
To do this, engineers had to turn to one of history's
most vital innovations...
to stand any chance of successfully defending
the country, the R.A.F. Needed a way of knowing
if an attack was imminent.
This was a huge problem.
...To make the impossible possible.
The littoral combat ships.
As the U.S. Navy's fastest war vessels,
these pioneering ships can patrol
the shallowest coastlines across the planet
with incredible dexterity.
But to determine friend from foe,
engineers had to turn to a revolutionary
breakthrough from the past.
Oh, ho ho!
Engineer Luke Bisby is flying in the British royal
air force's iconic biplane, the tiger moth.
He's here to reveal an ingenious secret
behind wartime engineering.
One amazing airplane.
In the mid 1930s, around the time that this aircraft
was being used to train R.A.F. Pilots,
the skies around the south coast of Britain
were actually a fairly empty place.
But with another war looming on the horizon,
the air ministry was facing a serious problem.
German's long-range zeppelin bombers
had terrorized London during the first world war,
and Britain's air defenses
struggled to cope with the attack.
To stand any chance of successfully defending
the country, the R.A.F. Needed a way of knowing
if an attack was imminent
so they could get their own fighters into the air.
This was a huge problem.
Scottish physicist Robert Watson watt
needed to overcome this hurdle.
Working as a meteorologist during the first world war,
watt detected the signals emitted
from lightning by bouncing radio waves
off of storm formations.
And in 1935, with another war looking increasingly likely,
he theorized that rather than bouncing radio waves
off of thunderstorms,
he could use them to detect incoming aircraft.
He named his invention radio detection and ranging,
eventually shortened to radar,
and it dramatically changed the outcome
of the second world war.
This is how watt's system worked.
In front of me, I have a slinky, which is stretched out
between me and a potential incoming aircraft.
And to work out the position of that incoming aircraft,
a radio wave would be sent out into the sky,
and I can simulate that by shaking this slinky.
So you can see that when I send out a radio wave
and it hits the aircraft, it gets reflected back,
and I can detect the aircraft's presence.
Because we know that radio waves travel at the speed of light,
by working out the time difference
between the time that the signal is sent out
and the time that it comes back,
I can determine how far away an aircraft is.
And this was something that had never been done before.
In 1935, watt successfully demonstrated
his new system to the air ministry, and by 1938,
the first five radar stations
covering aerial approaches
into London became operational.
The system was code named chain home,
and it relied on huge masts like this one to send
radio waves out into the sky.
By the outbreak of world war ii,
a network of 21 steel transmitters
and wooden receivers
were constructed along the Southern
and eastern coasts of the U.K.
all right.
Ah.
Oh.
That is a pretty amazing view.
The chain home system was the first application
of a radar air defense system anywhere in the world,
and it gave the British a vital edge over the Germans.
It was so powerful, it could even detect
a German aerial formation over 150 miles away.
And in 1939, the chain home low system was added,
which allowed observers to detect not only distance,
but also height.
And this is a really incredible piece of engineering.
80 years later, these incredible combat ships
are patrolling the world's
challenging coastal environments.
- Captain's on the bridge. - Carry on.
And crews aboard the independence variant
have the next generation of watt's engineering
breakthrough at their disposal...
the sea giraffe radar.
We need a radar that kind of packs a big radar punch,
but in a small package.
And that's what we get with the sea giraffe radar.
You want to come over here, sir, we will...
First, it goes through the nav plan.
Okay.
In congested, potentially-hostile waters,
this state-of-the-art radar system
helps the u.S.S. Independence
determine friend from foe.
Once we get here, we've got our critical points
in for contacting harbor control.
Okay.
There could be potentially several different small craft
coming in, up to 40 or 50 knots at the ship.
You need to have that capability,
where there's a lot of ambiguity
between the good guys,
the bad guys, and the in betweens.
The sea giraffe radar can detect 200 airborne
and up to 400 seaborne targets simultaneously.
But to simplify this complex picture,
its advanced radar technology
analyzes characteristics
such as altitude and speed to determine
if there's a threat within seconds.
Its ability to provide a very clear picture
to the operator is what makes it special.
We can separate the weak from the chaff from a radar picture
much better than a traditional radar would.
Even more incredible, this advanced radar system
is both smaller and lighter than a typical destroyer's.
It all is in keeping with our desire
to maintain speed and agility,
and it's a perfect fit for L.C.S.
the littoral combat ship fleet
navigates parts of the planet the U.S. Navy
once considered impossible.
I feel like we're doing something
that we haven't done before.
I truly think that this is pushing the boundaries.
And this inspired engineering will continue
to open up new horizons.
The opportunity going forward is limitless
with what we can do with these ships.
I'm just so extremely excited for the crew
that's gonna get the opportunity to sail in this ship
and take her around the world.
By learning from the pioneers of the past... Yes!
...up-scaling and developing innovations of their own,
engineers have written a new chapter in nautical design,
making the impossible... Possible.
She's basically one of a kind as far as warships goes.
I am sailing a ship that's unprecedented.
You can't find another ship in naval history
that's able to achieve similar features
as a littoral combat ship.