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Today on
"Impossible engineering,"
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the Shanghai Maglev...
The fastest passenger train
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on the planet,
with a top operating speed
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00:00:09,844 --> 00:00:12,811
of 268 miles per hour.
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The Maglev is faster than
the formula one car.
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It is flying along.
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A train that defies
the most basic laws of motion.
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The thing that's
different and very unique
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about the Maglev is the fact
that it floats.
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It took centuries of innovation
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and experimentation...
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Wow, it looks like something
out of the future.
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To make the impossible possible.
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Captions by vitac
www.Vitac.Com
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captions paid for by
Discovery communications
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China is a country on the rise.
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Its largest and wealthiest city,
Shanghai,
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attracts people
from all over the world
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with its ambition.
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As Shanghai's population
increases,
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so does its demand for space.
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The city faces
heavy traffic jams
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and congestion on a daily basis.
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Shanghai is busy.
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Cars, as well as buildings,
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fight for space on the ground.
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It can be very difficult
to move around.
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By the beginning
of the 21st century,
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Shanghai streets were
at maximum capacity.
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A heavily congested
eight-Lane highway
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was the city's only link
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to the Pudong
international airport.
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To get to the airport by car,
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it takes 45 minutes.
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You really need something
to cut through the city
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to get to the airport
without stopping
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and without encountering
any other vehicles.
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I, like most people
in this city,
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don't have time
to sit in traffic.
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China's solution...
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The Shanghai Maglev,
or transrapid...
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A cutting-edge,
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high-speed train,
the fastest in the world.
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The thing that's
different and very unique
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about the Maglev is the fact
that it floats.
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It hasn't got any wheels.
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It floats across the guideway
all the way to the airport.
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Now the Maglev is just about
to pull out of the station.
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When it's at its top speed,
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it'll be moving
at 431 kilometers an hour.
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That is just beyond belief,
incredible.
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To design a passenger train
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capable of reaching
268 miles per hour,
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the Maglev's engineering team
had to toss out
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many of the design features
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we've come to associate
with trains.
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First, their train
wouldn't have an engine.
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Huh?
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Then they would do away
with one of engineering's
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most fundamental inventions...
The wheel.
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Finally, they would defy
the most basic laws of motion.
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Ow!
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Ooh!
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Wow! Ooh!
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But before engineers
could design
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their futuristic train
with no engine or wheels,
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they had to figure out
a way to fit it
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into the already overcrowded
streets of Shanghai.
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Shanghai is one of
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the most heavily populated
cities in the world,
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and the population
is increasing.
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Now, building the infrastructure
it needs is very challenging
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just because there is no space.
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Like all the buildings
around here,
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the only place really to build
is to go up.
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Chicago is one of
the world's busiest cities.
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The logistical challenge of
moving around its inhabitants
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is a daunting task...
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But the city's early planners
came up with an idea
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over 100 years ago that still
keeps the city moving today.
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In the late 19th century,
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Chicago is one of
the fastest-growing cities,
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if not the fastest-growing city
in the world.
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In the 1840s,
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shortly after the city
was established,
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we had roughly about
4,000 people.
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And by 1900, we've got over
a million and a half.
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Our city is rapidly expanding.
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It's almost the Shanghai
of the late 19th century.
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So, how did engineers
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and planners deal with the need
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to transport the city's
growing population
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without clogging the busy
city streets even further?
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So this is the solution
that was developed,
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to elevate the city's rail lines
above the street traffic.
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Although it's not cheap to do
this type of infrastructure,
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it is cheaper, of course,
than building subways.
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Work began
on Chicago's train in 1892...
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But building tracks
30 feet above
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the city streets was not
welcomed by everybody.
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Third-floor apartment tenants
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now had to keep their curtains
closed if they wanted privacy,
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and young women were
warned to be careful
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of roving,
railborne Peeping Toms.
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Nevertheless, the system
was a big hit for most.
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It was lovingly nicknamed
the "I," short for elevated.
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We're here at Quincy.
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This "I" station
has been restored,
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and it gives us a sense of what
commuters would have seen
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00:07:04,258 --> 00:07:05,791
in the late 1890s.
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And the basic concept of moving
people in and out of the city
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at a different level
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than street level has not
changed since then.
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Elevating the city's train
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was a solution so successful
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that, more than 120 years later,
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the "I" is still transporting
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a half-million passengers
each day.
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The growth of the "I"
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and the growth of Chicago
are synonymous.
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The boom of population
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in the late 19th century
follows right along
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00:07:36,056 --> 00:07:38,190
with the growth of
this transit system.
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And I don't think, without
the "I," we would have had
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this great, vibrant American
city that we have today.
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Engineers of the Shanghai Maglev
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are taking Chicago's idea
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of an elevated
passenger train...
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Ooh!
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That was fast.
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...And giving it
a 21st century twist.
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Engineers of the Shanghai Maglev
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have taken Chicago's
century-old solution
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00:08:26,106 --> 00:08:28,740
of an elevated railroad
and created their own
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00:08:28,742 --> 00:08:31,943
19-mile guideway
high above the city streets.
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The advantage
a system like this has
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in already built-up urban spaces
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is it's very easy to install.
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It doesn't interfere
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with underground services.
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It doesn't interfere
with existing
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infrastructure at ground level,
which is really good.
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But building
an elevated guideway
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in this part of the world
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came with some
unique challenges.
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Shanghai sits in an area
of great seismic activity.
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It also has weak Clay soil.
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00:09:08,982 --> 00:09:12,250
The risk of liquefaction
is very high.
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Liquefaction is an unusual
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00:09:16,723 --> 00:09:18,390
and dramatic phenomenon
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that can occur during
an earthquake,
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when solid ground turns to mush.
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Aah!
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Physicist Andrew Steele
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has prepared a simple
demonstration
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to show how liquefaction works.
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So this water represents
the groundwater.
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This ground has got
a very high water table,
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so it's only got a thin layer
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of dry soil on top of
the saturated soil underneath.
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So, imagine you build
on this land,
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you construct
your beautiful city.
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But you built on Sandy soil,
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and you build on a fault line.
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So there's the danger
of an earthquake.
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You can see that,
as you shake it,
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then the groundwater
is forced up
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into the top layer of the soil,
and that changes its state
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from that of a solid to very
much behaving like a liquid,
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and the buildings are just
sinking straight into it.
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Earthquakes are
a constant threat in Shanghai.
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If the ground liquefies,
the Maglev's designers
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had to ensure the tracks
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wouldn't sink
into the soft soil.
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So engineers developed
a technique called piling.
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They built each support pier
on top of a giant concrete cap.
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Underneath the caps are concrete
piles,
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which are driven 200 feet
into the ground.
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If the soil near the surface
liquefies,
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the deep roots will hold
the Maglev's track in place.
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In less than nine months,
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Chinese engineers constructed
over 2,500 concrete columns
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to support the guideway.
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This would be
the fastest train in the world.
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But trying to get
a train up to speeds
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pushing 500 kilometers an hour,
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designers would be faced
with the problem
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of wind resistance or drag.
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00:11:17,127 --> 00:11:21,162
The greater the speed,
the greater the resistance.
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And all this air movement has
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the potential effect
of slowing the train down
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and wasting valuable energy.
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To build a train
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that can break
300 miles per hour,
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engineers had to look back
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to the great innovations
of the past for the solution.
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The earliest evidence
of railroads
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can be traced back
to ancient Greece.
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Men and animals pulled wheeled
vehicles in limestone grooves.
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The grooves prevented the wagons
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from leaving
their intended route.
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Railroads were developed as
a way of reducing friction.
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00:12:06,643 --> 00:12:09,677
In 1805, the English discovered
that a good horse
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on an ordinary road could pull
a wagon weighing a ton.
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00:12:16,353 --> 00:12:19,020
But on rails,
that same horse could pull
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00:12:19,022 --> 00:12:22,490
12 wagons each weighing
three tons for six miles
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in just two hours.
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Oh.
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When steam power was introduced,
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continents could be
crossed with ease,
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00:12:33,069 --> 00:12:35,136
transforming the modern world.
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00:12:41,577 --> 00:12:44,679
Railroads dramatically
changed the way we live.
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00:12:44,681 --> 00:12:47,816
But throughout the 19th
and early 20th century,
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00:12:47,818 --> 00:12:52,187
train design was
at a standstill.
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00:12:52,189 --> 00:12:55,089
Train design fundamentally
hadn't changed for 100 years
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since this, stephenson's rocket.
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00:12:56,760 --> 00:12:58,593
You can see the classic
cylindrical boiler.
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00:12:58,595 --> 00:13:00,562
We got a smokestack
at the front,
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00:13:00,564 --> 00:13:05,233
and its completely snubbed,
flat, unaerodynamic nose.
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00:13:05,235 --> 00:13:08,136
It would take a radical thinker
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to shake things up.
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00:13:13,976 --> 00:13:17,345
And in the 1930s, england
steam locomotive engineer
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00:13:17,347 --> 00:13:20,915
Nigel Gresley designed a new,
sleek machine that would,
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00:13:20,917 --> 00:13:23,551
at the time, be the fastest
train in the world...
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00:13:25,888 --> 00:13:28,289
The Mallard.
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00:13:28,291 --> 00:13:31,092
Everything about this
locomotive is designed to go
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as fast as possible.
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00:13:32,796 --> 00:13:36,130
You've got these massive wheels
driving it forward.
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00:13:36,132 --> 00:13:38,500
We've got a double chimney
to suck out the exhaust
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00:13:38,502 --> 00:13:40,335
as quickly as possible
at high speed,
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00:13:40,337 --> 00:13:43,571
and then you've got this
beautiful streamlined shape
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00:13:43,573 --> 00:13:46,474
in stark contrast to the trains
that had come before.
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00:13:46,476 --> 00:13:49,110
Gresley used a wind tunnel
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00:13:49,112 --> 00:13:50,712
to develop the Mallard.
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00:13:50,714 --> 00:13:52,647
Wind tunnels
had been used on planes
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00:13:52,649 --> 00:13:54,682
but never on a train before.
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00:13:54,684 --> 00:13:57,619
He made some interesting
discoveries.
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00:14:01,557 --> 00:14:04,993
Andrew Steele is visiting a test
center called the train rig
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00:14:04,995 --> 00:14:07,161
to see firsthand the difference
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00:14:07,163 --> 00:14:10,398
a streamlined train design
can create.
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00:14:10,400 --> 00:14:13,167
This is the test track.
It's 150 meters long,
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00:14:13,169 --> 00:14:16,237
and we can accelerate trains
to 75 meters a second,
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00:14:16,239 --> 00:14:20,675
which is over
250 kilometers an hour.
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00:14:20,677 --> 00:14:22,277
Today we've got
two different trains
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00:14:22,279 --> 00:14:23,611
that we're going to be testing.
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00:14:23,613 --> 00:14:25,179
This is a flat-nosed
freight train,
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00:14:25,181 --> 00:14:27,215
which represents sort of
an unaerodynamic train
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00:14:27,217 --> 00:14:28,716
as they were
originally designed.
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00:14:28,718 --> 00:14:31,252
And this one here
is a high-speed train.
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00:14:31,254 --> 00:14:32,487
Got this sloped nose.
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00:14:32,489 --> 00:14:33,955
We're going to see what
difference that makes
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00:14:33,957 --> 00:14:35,290
to the speed the train
can travel at.
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00:14:35,292 --> 00:14:36,758
And this is what
we're going to be using
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00:14:36,760 --> 00:14:37,926
for the actual experiment.
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00:14:37,928 --> 00:14:39,327
These things here
are light gates.
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00:14:39,329 --> 00:14:40,762
And when the train
goes past this one,
257
00:14:40,764 --> 00:14:42,964
it interrupts the light beam,
and we can detect that time.
258
00:14:42,966 --> 00:14:44,766
Then, a fraction
of a second later,
259
00:14:44,768 --> 00:14:47,302
it'll go past this light gate,
interrupts this beam,
260
00:14:47,304 --> 00:14:49,771
and by measuring the difference
between two times,
261
00:14:49,773 --> 00:14:51,139
we know this distance here,
262
00:14:51,141 --> 00:14:53,908
so we can work out exactly
how fast it's going.
263
00:14:58,714 --> 00:15:00,248
The model trains are fired
264
00:15:00,250 --> 00:15:02,417
using giant rubber catapults.
265
00:15:04,119 --> 00:15:07,288
So I was just applying
some tension to the track now,
266
00:15:07,290 --> 00:15:11,092
and that's pulling the train
back into the firing position.
267
00:15:11,094 --> 00:15:14,495
I'm almost as tense
as the train is.
268
00:15:14,497 --> 00:15:16,998
Okay.
269
00:15:17,000 --> 00:15:19,467
So just...
Here goes.
270
00:15:26,909 --> 00:15:28,543
Ooh!
271
00:15:31,080 --> 00:15:33,181
That was fast.
272
00:15:33,183 --> 00:15:34,782
Ooh!
273
00:15:34,784 --> 00:15:36,484
And believe it or not,
274
00:15:36,486 --> 00:15:38,853
that was a sort of
slow test run.
275
00:15:41,490 --> 00:15:43,391
So now that we've done
that test run,
276
00:15:43,393 --> 00:15:45,493
the key thing is to find out
the readings that we got
277
00:15:45,495 --> 00:15:48,229
from these light meters.
278
00:15:48,231 --> 00:15:49,764
We've got two readings here.
279
00:15:49,766 --> 00:15:51,099
At the first set of light gates,
280
00:15:51,101 --> 00:15:52,834
it was doing about
36 meters per second.
281
00:15:52,836 --> 00:15:55,637
But then, by the time the second
set of light gates,
282
00:15:55,639 --> 00:15:57,639
just a couple of meters later,
it's only doing 34 1/2 meters
283
00:15:57,641 --> 00:15:59,307
a second, so you can see
it's lost some speed,
284
00:15:59,309 --> 00:16:01,042
the aerodynamic drag
has kicked in
285
00:16:01,044 --> 00:16:02,644
and slowed the train down.
286
00:16:02,646 --> 00:16:05,446
In the short distance
between gates,
287
00:16:05,448 --> 00:16:09,484
the flat-nosed train loses
around 5% of its speed.
288
00:16:13,355 --> 00:16:16,791
Next to be tested is
the sloping-nosed model.
289
00:16:16,793 --> 00:16:19,961
Ready, aim, and fire.
290
00:16:24,400 --> 00:16:26,834
Phew!
291
00:16:26,836 --> 00:16:30,038
Wow.
292
00:16:30,040 --> 00:16:31,806
Oh.
293
00:16:31,808 --> 00:16:35,009
The sloping-nosed
model's speed reduces by only 2%
294
00:16:35,011 --> 00:16:37,178
between the light gates.
295
00:16:37,180 --> 00:16:39,013
Phew!
296
00:16:39,015 --> 00:16:41,115
So these numbers,
they're quite subtly different.
297
00:16:41,117 --> 00:16:43,084
But when you scale it up
to a full-sized train
298
00:16:43,086 --> 00:16:45,486
and you're looking to propel it
constantly down the track,
299
00:16:45,488 --> 00:16:47,989
this can translate into a big
change of efficiency.
300
00:16:50,292 --> 00:16:51,793
A fact
301
00:16:51,795 --> 00:16:55,329
Nigel Gresley discovered
while designing the Mallard
302
00:16:55,331 --> 00:16:56,664
and exploited brilliantly.
303
00:16:56,666 --> 00:16:58,399
Gresley's engineering really was
304
00:16:58,401 --> 00:16:59,734
a complete step change.
305
00:16:59,736 --> 00:17:01,769
Although we'd used aerodynamics
in planes
306
00:17:01,771 --> 00:17:04,605
and hydrodynamics was known
about in boats,
307
00:17:04,607 --> 00:17:05,807
this was the first time
308
00:17:05,809 --> 00:17:07,642
those principles had been
applied to a train.
309
00:17:07,644 --> 00:17:09,310
And that is what enabled
the Mallard
310
00:17:09,312 --> 00:17:10,678
to travel at 126 miles per hour.
311
00:17:10,680 --> 00:17:14,482
In 1938, the Mallard
set the record
313
00:17:14,484 --> 00:17:17,752
for the fastest
steam train on rails,
314
00:17:17,754 --> 00:17:20,221
a record which
still stands today.
315
00:17:32,768 --> 00:17:34,535
The designers of
the Shanghai Maglev
316
00:17:34,537 --> 00:17:36,704
have learned from
the breakthroughs
317
00:17:36,706 --> 00:17:39,073
made by the Mallard
and created a train
318
00:17:39,075 --> 00:17:42,844
that travels at speeds that
innovator Nigel Gresley
319
00:17:42,846 --> 00:17:45,179
would have thought
to be impossible.
320
00:17:45,181 --> 00:17:49,984
In one test run, it exceeded
300 miles per hour...
321
00:17:51,353 --> 00:17:55,590
Almost three times what
the Mallard was capable of.
322
00:17:55,592 --> 00:17:59,160
You can see it has a very sleek,
323
00:17:59,162 --> 00:18:00,595
streamlined design
324
00:18:00,597 --> 00:18:04,398
with a very smooth,
sloping nose.
325
00:18:04,400 --> 00:18:08,236
Also the train wraps itself
around the guideway
326
00:18:08,238 --> 00:18:11,973
which reduces turbulence that
might otherwise be generated
327
00:18:11,975 --> 00:18:14,408
between the train and the track.
328
00:18:22,751 --> 00:18:24,085
But to build
329
00:18:24,087 --> 00:18:26,587
the fastest passenger train
on the planet,
330
00:18:26,589 --> 00:18:29,257
engineers would need more than
just an aerodynamic design,
331
00:18:29,259 --> 00:18:31,759
so they drew inspiration
332
00:18:31,761 --> 00:18:33,561
from a decades-old
engineering experiment...
333
00:18:33,563 --> 00:18:35,396
They combined the principle
of the hovercraft
334
00:18:35,398 --> 00:18:37,298
and a jet engine,
335
00:18:37,300 --> 00:18:39,534
and they smashed
the rail speed record.
336
00:18:39,536 --> 00:18:43,704
...To create their own
impossible engineering.
337
00:18:55,951 --> 00:18:58,586
The Shanghai Maglev
338
00:18:58,588 --> 00:19:01,022
is the fastest passenger train
on the planet.
339
00:19:03,792 --> 00:19:08,362
It travels at an astonishing
top operating speed
340
00:19:08,364 --> 00:19:10,498
of 268 miles per hour.
341
00:19:19,374 --> 00:19:20,975
The train has transformed travel
342
00:19:20,977 --> 00:19:23,578
between downtown Shanghai
and Pudong airport.
343
00:19:27,349 --> 00:19:29,584
The Maglev runs
344
00:19:29,586 --> 00:19:32,386
all the way from here
to Pudong airport,
345
00:19:32,388 --> 00:19:36,224
which is a 34-kilometer journey
in that direction.
346
00:19:36,226 --> 00:19:38,526
Now if I was to get the Metro,
347
00:19:38,528 --> 00:19:40,561
it would take me over an hour.
348
00:19:40,563 --> 00:19:43,998
If I got a cab, it would take me
40 minutes or so.
349
00:19:44,000 --> 00:19:46,901
But if I got the Maglev,
which I like to do,
350
00:19:46,903 --> 00:19:48,803
it takes me only seven minutes.
351
00:19:50,806 --> 00:19:53,441
But the development
352
00:19:53,443 --> 00:19:56,844
of the futuristic Maglev
took decades of experimentation
353
00:19:56,846 --> 00:20:02,683
before it reached its incredible
21st century performance levels.
354
00:20:02,685 --> 00:20:04,485
Created in Germany,
355
00:20:04,487 --> 00:20:07,088
the first
passenger-carrying prototype,
356
00:20:07,090 --> 00:20:09,957
the transrapid Maglev system,
was unveiled
357
00:20:09,959 --> 00:20:11,192
in 1971.
358
00:20:11,194 --> 00:20:12,760
It traveled at speeds
359
00:20:12,762 --> 00:20:15,963
where little consideration
to aerodynamics was necessary.
360
00:20:17,733 --> 00:20:19,267
But as experiments continued
361
00:20:19,269 --> 00:20:20,835
and speeds rapidly increased,
362
00:20:20,837 --> 00:20:24,038
the train car design
that now graces
363
00:20:24,040 --> 00:20:26,107
Shanghai's elevated track
took shape.
364
00:20:30,946 --> 00:20:33,180
However, increased speed
365
00:20:33,182 --> 00:20:36,884
means increased
engineering challenges.
366
00:20:36,886 --> 00:20:39,520
The Maglev going to the airport
367
00:20:39,522 --> 00:20:41,422
and the Maglev
coming from the airport
368
00:20:41,424 --> 00:20:44,625
pass each other at
incredible speeds,
369
00:20:44,627 --> 00:20:48,195
potentially
a combined speed of over
370
00:20:48,197 --> 00:20:49,997
860 kilometers per hour.
371
00:20:49,999 --> 00:20:54,068
And this could cause
a potential problem.
372
00:20:54,070 --> 00:20:56,637
However sleek the design,
373
00:20:56,639 --> 00:21:00,308
any object passing
another at speed
374
00:21:00,310 --> 00:21:03,444
creates a change in pressure
between them.
375
00:21:03,446 --> 00:21:07,949
Lower pressure,
as the trains are together,
376
00:21:07,951 --> 00:21:11,585
followed by a return to a higher
pressure once they've passed.
377
00:21:11,587 --> 00:21:15,022
This could potentially cause
stresses to the cabin walls.
378
00:21:15,024 --> 00:21:16,590
So maglevs have been engineered
379
00:21:16,592 --> 00:21:20,428
with an aluminium
composite shell,
380
00:21:20,430 --> 00:21:24,699
light, but at the same time,
strong and stiff enough
381
00:21:24,701 --> 00:21:26,667
to support the pressure
382
00:21:26,669 --> 00:21:29,870
acting on the structure
by high-speed traveling.
383
00:21:35,010 --> 00:21:37,144
But there were
other design elements
384
00:21:37,146 --> 00:21:39,513
that the Maglev's engineers
had to consider
385
00:21:39,515 --> 00:21:42,917
if they wanted their train to
achieve record-breaking speeds.
386
00:21:42,919 --> 00:21:44,819
It's not just the wind
387
00:21:44,821 --> 00:21:47,188
that provides friction
on the train.
388
00:21:47,190 --> 00:21:49,890
One of the biggest
losses of energy
389
00:21:49,892 --> 00:21:52,827
that occurs
in a traditional train
390
00:21:52,829 --> 00:21:54,729
is produced by the friction
391
00:21:54,731 --> 00:21:57,264
between the wheels
and the track.
392
00:21:57,266 --> 00:22:00,835
The more friction there is,
the more power is lost.
393
00:22:00,837 --> 00:22:03,771
In a car like this, for example,
394
00:22:03,773 --> 00:22:09,176
1/3 of the fuel is spent on
overcoming friction.
395
00:22:12,247 --> 00:22:14,715
To limit the negative
effects of friction,
396
00:22:14,717 --> 00:22:17,151
engineers designed
the Maglev in a way
397
00:22:17,153 --> 00:22:20,921
that only some of history's most
daring engineers have attempted.
398
00:22:33,235 --> 00:22:35,169
Physicist Andrew Steele is in
399
00:22:35,171 --> 00:22:38,439
the French countryside looking
for the remains of a system
400
00:22:38,441 --> 00:22:40,775
that could have been
just as revolutionary
401
00:22:40,777 --> 00:22:42,877
as the Maglev.
402
00:22:48,316 --> 00:22:51,786
So here it is, over 50 years old
and covered in moss.
403
00:22:51,788 --> 00:22:54,622
This is what its creators
thought would be
404
00:22:54,624 --> 00:22:57,024
the future of
high-speed mass transit...
405
00:22:57,026 --> 00:22:59,894
A single concrete rail,
straddled by a train,
406
00:22:59,896 --> 00:23:01,228
capable of traveling
407
00:23:01,230 --> 00:23:04,231
at 422 kilometers an hour,
at a time
408
00:23:04,233 --> 00:23:06,167
when the speed record
for a conventional train
409
00:23:06,169 --> 00:23:07,368
was just half that.
410
00:23:07,370 --> 00:23:09,770
So what kind of vehicle
411
00:23:09,772 --> 00:23:13,674
was capable of overcoming
the forces of friction
412
00:23:13,676 --> 00:23:16,444
to travel over
250 miles per hour?
413
00:23:16,446 --> 00:23:20,414
The answer lies in
a closely guarded warehouse.
414
00:23:20,416 --> 00:23:23,551
I've come to
a top-secret location
415
00:23:23,553 --> 00:23:24,919
somewhere outside Paris
416
00:23:24,921 --> 00:23:27,455
to get a rare look
at what could have been
417
00:23:27,457 --> 00:23:29,557
the future of land
transportation.
418
00:23:32,727 --> 00:23:34,962
Hello.
Good morning.
419
00:23:34,964 --> 00:23:35,996
So, where's it kept?
420
00:23:44,439 --> 00:23:47,074
Hidden among
421
00:23:47,076 --> 00:23:49,043
an assortment
of military vehicles
422
00:23:49,045 --> 00:23:53,614
are the last surviving examples
of an extraordinary experiment.
423
00:24:04,059 --> 00:24:05,693
Wow.
424
00:24:05,695 --> 00:24:07,528
So this is the Aérotrain.
Yes.
425
00:24:07,530 --> 00:24:09,730
It looks like something
out of the future.
426
00:24:15,470 --> 00:24:19,073
Designed by engineer
Jean Bertin in the 1960s,
427
00:24:19,075 --> 00:24:24,011
the Aérotrain 01 and 02 are
the only surviving prototypes
428
00:24:24,013 --> 00:24:27,314
of a system that hoped to change
train travel forever.
429
00:24:31,052 --> 00:24:34,788
You can see the Aérotrain
doesn't have any wheels.
430
00:24:34,790 --> 00:24:36,891
Now that might seem strange,
431
00:24:36,893 --> 00:24:38,759
but although the wheels
have been the basis
432
00:24:38,761 --> 00:24:40,594
for land transport
for thousands of years,
433
00:24:40,596 --> 00:24:42,363
they come with a big
disadvantage,
434
00:24:42,365 --> 00:24:44,465
because the wheels
rub against the ground.
435
00:24:44,467 --> 00:24:45,833
They create friction,
436
00:24:45,835 --> 00:24:47,768
and the Aérotrain
tries to get around that.
437
00:24:51,406 --> 00:24:54,441
Engineers and scientists have
been toying with the idea
438
00:24:54,443 --> 00:24:56,110
of frictionless travel
for some time.
439
00:24:56,112 --> 00:24:57,778
The idea is that,
if you can remove
440
00:24:57,780 --> 00:24:59,480
that frictional resistance
to motion,
441
00:24:59,482 --> 00:25:01,649
then you can make things travel
faster and more efficiently.
442
00:25:01,651 --> 00:25:03,951
The simplest way
to do that might be
443
00:25:03,953 --> 00:25:05,719
to levitate it
on a cushion of air,
444
00:25:05,721 --> 00:25:08,322
and that's the principle behind
how a hovercraft works.
445
00:25:08,324 --> 00:25:10,491
We've got our own very simple
model of a hovercraft here.
446
00:25:10,493 --> 00:25:12,493
It's just a cd with the top
of a drinks bottle on it
447
00:25:12,495 --> 00:25:14,061
and then a balloon.
448
00:25:14,063 --> 00:25:15,963
Before we inject
that cushion of air,
449
00:25:15,965 --> 00:25:18,632
the cd only moves a very small
distance across the table
450
00:25:18,634 --> 00:25:19,967
when I tap it.
451
00:25:19,969 --> 00:25:21,302
However, what we can do
452
00:25:21,304 --> 00:25:23,237
is attach a balloon
to this drinks bottle top
453
00:25:23,239 --> 00:25:25,406
and see if that makes
any difference
454
00:25:25,408 --> 00:25:27,241
to the way that the cd moves.
455
00:25:27,243 --> 00:25:29,843
So here we go.
456
00:25:29,845 --> 00:25:31,879
You can see that now,
with a tiny tap,
457
00:25:31,881 --> 00:25:33,547
the cd moves a long way.
458
00:25:33,549 --> 00:25:35,950
And just as long as the balloon
has got some pressure
459
00:25:35,952 --> 00:25:37,885
to force that air down
underneath the cd,
460
00:25:37,887 --> 00:25:39,787
then it'll keep on
moving around freely.
461
00:25:39,789 --> 00:25:41,388
But when the balloon runs out,
of course,
462
00:25:41,390 --> 00:25:43,424
the cushion of air vanishes
and the cd is just as hard
463
00:25:43,426 --> 00:25:45,893
to move across the table
as it was before.
464
00:25:48,029 --> 00:25:51,031
In here, we've got the guts
of the Aérotrain.
465
00:25:51,033 --> 00:25:52,866
And incredibly,
there were just two regular
466
00:25:52,868 --> 00:25:54,902
car engines
which power massive fans.
467
00:25:54,904 --> 00:25:56,570
And that blasts air downwards
468
00:25:56,572 --> 00:25:59,373
to lift the train up off
the ground and then inwards
469
00:25:59,375 --> 00:26:01,041
to keep it centered
on the track.
470
00:26:01,043 --> 00:26:02,977
That means the train isn't
in contact with the ground
471
00:26:02,979 --> 00:26:05,012
or the track, and so that source
of friction is removed,
472
00:26:05,014 --> 00:26:06,614
and that means that
more of the energy
473
00:26:06,616 --> 00:26:07,948
from this engine up here,
474
00:26:07,950 --> 00:26:10,384
the propeller, can be used
to power the train
475
00:26:10,386 --> 00:26:12,353
to move forwards.
476
00:26:12,355 --> 00:26:15,990
It's 11 meters long,
weighs 2.6 tons,
477
00:26:15,992 --> 00:26:18,559
and yet the air gushing
out of these nozzles
478
00:26:18,561 --> 00:26:20,894
is enough to keep it floating
two or three millimeters
479
00:26:20,896 --> 00:26:23,163
above the track.
480
00:26:27,335 --> 00:26:29,136
By 1967,
481
00:26:29,138 --> 00:26:31,505
the Aérotrain was proving
its potential
482
00:26:31,507 --> 00:26:33,340
on the test track
as the next generation
483
00:26:33,342 --> 00:26:34,608
of passenger transport.
484
00:26:34,610 --> 00:26:37,344
A plan to build a track
485
00:26:37,346 --> 00:26:39,747
for the Aérotrain between
Paris and Orléans...
486
00:26:39,749 --> 00:26:41,148
65 miles in 35 minutes.
487
00:26:44,587 --> 00:26:47,354
For Aérotrain mark 02,
488
00:26:47,356 --> 00:26:50,190
Jean Bertin went
all out for speed.
489
00:26:52,794 --> 00:26:54,295
The Aérotrain 02
490
00:26:54,297 --> 00:26:57,731
was a futuristic combo
of fighter jet, race car,
491
00:26:57,733 --> 00:27:00,501
train, and hovercraft.
492
00:27:01,903 --> 00:27:04,371
It looks like something
out of a Sci-Fi movie,
493
00:27:04,373 --> 00:27:07,074
but the technology itself
is actually pretty simple.
494
00:27:07,076 --> 00:27:09,143
I think my favorite control
495
00:27:09,145 --> 00:27:11,145
is this one that goes marché
and arret.
496
00:27:11,147 --> 00:27:13,847
So it's basically stop and go
just by flicking a switch.
497
00:27:13,849 --> 00:27:16,984
Nevertheless,
it was the combination
498
00:27:16,986 --> 00:27:18,385
of engineering ideas
499
00:27:18,387 --> 00:27:21,689
that made Jean Bertin's
Aérotrain groundbreaking.
500
00:27:21,691 --> 00:27:24,892
Bertin's ideas
really were revolutionary.
501
00:27:24,894 --> 00:27:27,761
They combined the principle of
the hovercraft and a jet engine.
502
00:27:27,763 --> 00:27:30,130
This was the first time
it had ever been done.
503
00:27:30,132 --> 00:27:32,466
Combined, they smashed
the rail speed record.
504
00:27:32,468 --> 00:27:34,601
An aircraft jet engine
gives initial thrust
505
00:27:34,603 --> 00:27:38,072
up to speeds of around
185 miles per hour.
506
00:27:38,074 --> 00:27:42,276
An additional rocket motor
boosts the mph to 235.
507
00:27:50,352 --> 00:27:52,119
Sadly,
508
00:27:52,121 --> 00:27:54,254
Jean Bertin's dream
of friction-free travel
509
00:27:54,256 --> 00:27:56,690
died in the 1970s
510
00:27:56,692 --> 00:27:59,226
when the French government
abandoned the experiment.
511
00:28:03,631 --> 00:28:05,866
But almost a half century later,
512
00:28:05,868 --> 00:28:09,670
the Aérotrain has
a familiar-looking cousin
513
00:28:09,672 --> 00:28:12,639
over 3,000 miles away in China.
514
00:28:23,084 --> 00:28:24,585
The Shanghai Maglev...
515
00:28:24,587 --> 00:28:27,654
The world's fastest
passenger train,
516
00:28:27,656 --> 00:28:29,957
a unique engineering feat
517
00:28:29,959 --> 00:28:33,727
situated in one of China's
most ambitious cities.
518
00:28:36,598 --> 00:28:38,332
This Maglev here is the only
519
00:28:38,334 --> 00:28:41,335
high-speed Maglev in the world,
and that kind of
520
00:28:41,337 --> 00:28:43,437
chimes in with
the ambition of Shanghai.
521
00:28:43,439 --> 00:28:47,508
People come here to design
daring buildings
522
00:28:47,510 --> 00:28:49,176
and daring systems.
523
00:28:49,178 --> 00:28:51,712
And one of
the most daring of them all
524
00:28:51,714 --> 00:28:52,946
is the Maglev...
525
00:28:54,516 --> 00:28:58,385
Traveling at a staggering
268 miles per hour,
526
00:28:58,387 --> 00:29:02,189
appearing to defy physics.
527
00:29:21,743 --> 00:29:24,912
The first time I
traveled in the Maglev,
528
00:29:24,914 --> 00:29:27,714
we hit 400, and I thought,
"oh, my goodness."
529
00:29:27,716 --> 00:29:30,851
And then it continued
to travel even faster.
530
00:29:30,853 --> 00:29:34,054
I could not believe what I was
seeing and experiencing.
531
00:29:34,056 --> 00:29:37,458
And it is currently doing
a top speed,
532
00:29:37,460 --> 00:29:42,162
flying pretty much at
431 kilometers an hour.
533
00:29:42,164 --> 00:29:45,265
And it still feels
very comfortable
534
00:29:45,267 --> 00:29:47,134
for the speed at which
it's traveling.
535
00:29:47,136 --> 00:29:49,970
The Maglev is faster
than the formula one car.
536
00:29:49,972 --> 00:29:51,705
It is flying along.
537
00:29:53,041 --> 00:29:56,310
The Maglev's record-
breaking speed is possible
538
00:29:56,312 --> 00:29:57,945
because it's levitated
above the track
539
00:29:57,947 --> 00:29:59,346
by powerful electromagnets
540
00:29:59,348 --> 00:30:03,150
instead of a hovercraft design
like the French Aérotrain.
541
00:30:08,823 --> 00:30:10,991
But levitating
a train with magnets
542
00:30:10,993 --> 00:30:14,795
would be impossible without one
of science's great innovators.
543
00:30:25,640 --> 00:30:27,774
Born in 1791,
544
00:30:27,776 --> 00:30:30,110
Michael Faraday was the son
of a blacksmith
545
00:30:30,112 --> 00:30:32,346
and received little
formal education,
546
00:30:32,348 --> 00:30:34,448
but he would go on
to revolutionize
547
00:30:34,450 --> 00:30:35,949
the engineering world.
548
00:30:37,952 --> 00:30:39,786
His original laboratory
549
00:30:39,788 --> 00:30:43,724
still exists at London's
royal institution...
550
00:30:43,726 --> 00:30:45,492
I'm going to give it
a little push.
551
00:30:45,494 --> 00:30:46,827
Where physicist Andrew Steele
552
00:30:46,829 --> 00:30:49,897
is exploring how Faraday's
discoveries
553
00:30:49,899 --> 00:30:52,699
made magnetic levitation
possible.
554
00:30:52,701 --> 00:30:54,535
Faraday's discoveries
revolutionized
555
00:30:54,537 --> 00:30:56,303
our understanding
of the interplay
556
00:30:56,305 --> 00:30:58,071
between electricity
and magnetism.
557
00:30:58,073 --> 00:31:00,407
And one of the things that this
understanding allows us to make
558
00:31:00,409 --> 00:31:01,742
is an electromagnet.
559
00:31:01,744 --> 00:31:04,311
So an electromagnet is made
of a coil of wire.
560
00:31:04,313 --> 00:31:06,313
You then need to get the ends
of those pieces of wire
561
00:31:06,315 --> 00:31:07,981
and plug them into
a power supply.
562
00:31:07,983 --> 00:31:10,317
And, finally, to magnify
the magnetic effect,
563
00:31:10,319 --> 00:31:12,653
you often place a core
of a material like iron
564
00:31:12,655 --> 00:31:13,987
in the middle of the magnet.
565
00:31:13,989 --> 00:31:16,957
Let's connect this up.
566
00:31:16,959 --> 00:31:20,661
And to prove to you that
that's magnetic,
567
00:31:20,663 --> 00:31:21,895
you can see...
568
00:31:21,897 --> 00:31:24,097
That even with this extremely
simple setup,
569
00:31:24,099 --> 00:31:26,500
we can actually get a piece
of metal to stick to it.
570
00:31:26,502 --> 00:31:28,402
Another crucial factor
about electromagnets,
571
00:31:28,404 --> 00:31:30,571
if you want to use them
for levitation,
572
00:31:30,573 --> 00:31:32,639
is that we can change
their strength,
573
00:31:32,641 --> 00:31:34,241
and we can do that very easily.
574
00:31:34,243 --> 00:31:35,909
Just by changing
the electric current
575
00:31:35,911 --> 00:31:37,344
passing through this magnet,
576
00:31:37,346 --> 00:31:38,712
I can turn the current down
577
00:31:38,714 --> 00:31:40,380
and make the attraction
much weaker.
578
00:31:40,382 --> 00:31:42,716
Or I can turn the current up
and make that attraction
579
00:31:42,718 --> 00:31:44,785
get stronger again.
580
00:31:44,787 --> 00:31:47,321
Not only can
electromagnets be adjusted
581
00:31:47,323 --> 00:31:48,989
and turned on or off at will,
582
00:31:48,991 --> 00:31:54,828
but they're also significantly
stronger than ordinary magnets.
583
00:31:54,830 --> 00:31:56,496
If you want to suspend
an entire train,
584
00:31:56,498 --> 00:31:58,498
you're going to need a pretty
powerful electromagnet.
585
00:31:58,500 --> 00:32:00,334
And actually, electromagnets
are pretty strong.
586
00:32:00,336 --> 00:32:03,971
This little one is enough to
suspend my entire body weight.
587
00:32:03,973 --> 00:32:06,173
And actually,
588
00:32:06,175 --> 00:32:08,875
this thing needs surprisingly
little electric current.
589
00:32:08,877 --> 00:32:11,478
There's less electricity
flowing through this device
590
00:32:11,480 --> 00:32:14,481
than there is through your hair
dryer or your kettle at home.
591
00:32:14,483 --> 00:32:15,949
We've got an electrical current
592
00:32:15,951 --> 00:32:17,751
flowing through this
electromagnet.
593
00:32:17,753 --> 00:32:20,721
If we connect it to the piece
of metal on my back,
594
00:32:20,723 --> 00:32:24,291
then, hopefully, there should be
enough strength
595
00:32:24,293 --> 00:32:26,360
to hold me above the floor.
596
00:32:29,564 --> 00:32:31,064
And there you have it.
597
00:32:47,348 --> 00:32:49,149
On the Shanghai Maglev,
598
00:32:49,151 --> 00:32:50,484
powerful electromagnets
599
00:32:50,486 --> 00:32:54,121
are installed into the underside
of the train cars,
600
00:32:54,123 --> 00:32:56,823
allowing them to float.
601
00:32:56,825 --> 00:33:00,027
Guidance magnets
keep the train centered,
602
00:33:00,029 --> 00:33:02,195
and support magnets pull
the unit
603
00:33:02,197 --> 00:33:06,867
to the underside of the track,
lifting the train above.
604
00:33:06,869 --> 00:33:08,969
The entire train floats,
605
00:33:08,971 --> 00:33:12,105
suspended 10 millimeters
below the track.
606
00:33:16,044 --> 00:33:17,878
Not only does this reduce
wear and tear,
607
00:33:17,880 --> 00:33:20,080
but it also makes for
608
00:33:20,082 --> 00:33:23,283
extremely fast,
friction-free travel.
609
00:33:23,285 --> 00:33:26,153
Because there's no contact
610
00:33:26,155 --> 00:33:28,955
between the train
and the guideway,
611
00:33:28,957 --> 00:33:32,025
there is no friction,
and this means that the train
612
00:33:32,027 --> 00:33:34,394
can have a lifetime
of up to 50 years
613
00:33:34,396 --> 00:33:36,430
with minimum maintenance
required.
614
00:33:40,702 --> 00:33:42,035
But while designing
615
00:33:42,037 --> 00:33:43,770
China's futuristic
passenger train,
616
00:33:43,772 --> 00:33:46,740
developers couldn't just
focus on speed.
617
00:33:46,742 --> 00:33:48,909
They had to ensure the Maglev
618
00:33:48,911 --> 00:33:51,178
was environmentally
friendly, too.
619
00:33:51,180 --> 00:33:55,082
China,
like all modern economies,
620
00:33:55,084 --> 00:33:57,951
is worried about
its carbon emission quota.
621
00:33:57,953 --> 00:33:59,886
As development continues,
622
00:33:59,888 --> 00:34:04,024
the demand for oil
will also likely increase,
623
00:34:04,026 --> 00:34:07,928
but China has a limited
domestic oil supply.
624
00:34:07,930 --> 00:34:12,766
With its current gas-guzzling
congestion problems,
625
00:34:12,768 --> 00:34:15,902
greener transport initiatives
are drastically needed.
626
00:34:15,904 --> 00:34:18,739
Otherwise, the city will choke.
627
00:34:18,741 --> 00:34:21,374
Their environmentally
friendly solution
628
00:34:21,376 --> 00:34:25,112
came from one of history's
great engineering innovators.
629
00:34:31,686 --> 00:34:33,253
In the late 1940s,
630
00:34:33,255 --> 00:34:36,022
a British engineer's
groundbreaking experiment
631
00:34:36,024 --> 00:34:37,657
would earn him the nickname
632
00:34:37,659 --> 00:34:41,528
"the father of the Maglev."
633
00:34:41,530 --> 00:34:44,631
This is a sheet of aluminium.
634
00:34:44,633 --> 00:34:48,468
When I put it on the motor
and switch on the magnets,
635
00:34:48,470 --> 00:34:51,571
something pretty
dramatic occurs.
636
00:34:51,573 --> 00:34:54,841
Electrical genius
Eric laithwaite
637
00:34:54,843 --> 00:34:58,645
developed the first practical
linear electric motor,
638
00:34:58,647 --> 00:35:03,183
creating an effect he later
dubbed the magnetic river.
639
00:35:03,185 --> 00:35:05,552
First of all, it will levitate,
640
00:35:05,554 --> 00:35:08,355
or support, an aluminium plate.
641
00:35:08,357 --> 00:35:10,857
It will guide it sideways,
642
00:35:10,859 --> 00:35:13,360
and it will also
propel it along.
643
00:35:13,362 --> 00:35:15,962
The linear motor
644
00:35:15,964 --> 00:35:20,567
takes a traditional coiled
electric motor and unrolls it.
645
00:35:20,569 --> 00:35:24,538
Instead of spinning a rotor,
what was the coil, or stator,
646
00:35:24,540 --> 00:35:28,308
provides a bed that drives
the object along its length.
647
00:35:32,313 --> 00:35:35,715
And there you have your modern
648
00:35:35,717 --> 00:35:40,320
vehicle being guided,
lifted, and propelled,
649
00:35:40,322 --> 00:35:42,756
all by means of
the same set of coils.
650
00:35:42,758 --> 00:35:45,525
Laithwaite's experiments
651
00:35:45,527 --> 00:35:49,362
provided the key that unlocked
the potential of the Maglev.
652
00:35:59,807 --> 00:36:02,375
The builders of
the transrapid Maglev system
653
00:36:02,377 --> 00:36:05,812
constructed a series
of stator blocks.
654
00:36:05,814 --> 00:36:07,981
They are the main component
of the linear motor
655
00:36:07,983 --> 00:36:10,150
and act as the propulsion system
for the train.
656
00:36:13,287 --> 00:36:15,488
Once installed,
they were tested in Germany,
657
00:36:15,490 --> 00:36:17,991
and in combination
with the support
658
00:36:17,993 --> 00:36:22,796
and guidance magnets, enabled
the Shanghai Maglev to levitate.
659
00:36:30,238 --> 00:36:35,242
The train can travel
over 300 miles an hour
660
00:36:35,244 --> 00:36:37,711
without an on board engine.
661
00:36:39,914 --> 00:36:44,117
A linear motor
is embedded into the guideways.
662
00:36:44,119 --> 00:36:47,420
But don't be fooled
663
00:36:47,422 --> 00:36:52,092
into thinking this whole track
is electrified all the time.
664
00:36:52,094 --> 00:36:54,995
What is so brilliant
about this system
665
00:36:54,997 --> 00:36:58,098
is that only the sections
of the track
666
00:36:58,100 --> 00:37:00,133
on which the vehicle moves
667
00:37:00,135 --> 00:37:02,469
is powered at any time.
668
00:37:06,107 --> 00:37:11,611
So as it sets off, the track
ahead of it is dormant,
669
00:37:11,613 --> 00:37:15,048
and only the section in front
of the Maglev turns on.
670
00:37:15,050 --> 00:37:19,586
As soon as the Maglev has passed
over the short section of track,
671
00:37:19,588 --> 00:37:22,222
it turns off again,
672
00:37:22,224 --> 00:37:25,892
as the job of pushing
the Maglev along is taken up
673
00:37:25,894 --> 00:37:28,929
by the next section of track.
674
00:37:28,931 --> 00:37:32,832
And so on and so on,
all the way to its destination.
675
00:37:39,140 --> 00:37:41,741
But with less than six inches
676
00:37:41,743 --> 00:37:43,843
between the Maglev
and its guideway,
677
00:37:43,845 --> 00:37:46,713
even the slightest malfunction
could be catastrophic.
678
00:37:46,715 --> 00:37:49,082
It is critical to maintain
679
00:37:49,084 --> 00:37:53,019
an even gap between
the train and the track,
680
00:37:53,021 --> 00:37:55,922
no matter how many
passengers are on board.
681
00:37:55,924 --> 00:37:57,757
To do this,
the Maglev's builders
682
00:37:57,759 --> 00:38:01,795
had to create one last piece
of impossible engineering.
683
00:38:13,774 --> 00:38:16,176
Traveling at an astonishing
684
00:38:16,178 --> 00:38:18,011
268 miles per hour
685
00:38:18,013 --> 00:38:21,948
while floating on
a magnetic field,
686
00:38:21,950 --> 00:38:25,018
the Shanghai Maglev is the only
high-speed train of its kind
687
00:38:25,020 --> 00:38:27,520
operating commercially
in the world.
688
00:38:31,726 --> 00:38:34,594
But having a levitating train
fly through Shanghai
689
00:38:34,596 --> 00:38:38,031
at such high speeds comes with
several engineering challenges.
690
00:38:38,033 --> 00:38:43,269
There is a carriage
hurtling along
691
00:38:43,271 --> 00:38:46,239
at over 430 kilometers per hour.
692
00:38:46,241 --> 00:38:49,409
So it is critical to control
693
00:38:49,411 --> 00:38:52,012
fluctuations in
the magnetic field
694
00:38:52,014 --> 00:38:54,047
and maintain an even gap
695
00:38:54,049 --> 00:38:56,649
between the train and the track,
696
00:38:56,651 --> 00:39:00,120
no matter how many passengers
are on board
697
00:39:00,122 --> 00:39:02,956
or what variations there are
in the load it's carrying.
698
00:39:02,958 --> 00:39:05,792
With just six inches between
699
00:39:05,794 --> 00:39:09,929
the Maglev and its guideway,
any errors could see the train
700
00:39:09,931 --> 00:39:11,698
crunch into the track.
701
00:39:17,238 --> 00:39:19,339
The engineering team's solution,
702
00:39:19,341 --> 00:39:21,174
as physicist Andrew Steele
demonstrates,
703
00:39:21,176 --> 00:39:22,942
relies on sensors
constantly regulating
704
00:39:22,944 --> 00:39:26,179
the current flowing through
the electromagnets.
705
00:39:26,181 --> 00:39:27,514
There we go.
706
00:39:27,516 --> 00:39:29,749
You can see this
permanent magnet
707
00:39:29,751 --> 00:39:32,519
is suspended underneath
this electromagnet.
708
00:39:32,521 --> 00:39:34,187
Whenever
the permanent magnet moves
709
00:39:34,189 --> 00:39:35,688
slightly imperceptibly closer,
710
00:39:35,690 --> 00:39:38,024
this little sensor on
the bottom here detects that,
711
00:39:38,026 --> 00:39:39,959
sends a message down
to these electronics,
712
00:39:39,961 --> 00:39:42,295
and tells the electromagnet
to become a little bit weaker.
713
00:39:42,297 --> 00:39:43,797
It turns down the current.
714
00:39:43,799 --> 00:39:46,066
That allows the ball to fall
away a little bit.
715
00:39:46,068 --> 00:39:48,334
As it falls away,
the sensor detects that again
716
00:39:48,336 --> 00:39:50,603
and increases the strength
of the electromagnet
717
00:39:50,605 --> 00:39:52,372
and pulls the ball
back towards it.
718
00:39:52,374 --> 00:39:54,040
So one complication
of this system
719
00:39:54,042 --> 00:39:56,576
is that your feedback system
always needs to be working,
720
00:39:56,578 --> 00:39:58,378
and it needs to be
working very fast.
721
00:39:58,380 --> 00:39:59,479
You can see this ball
722
00:39:59,481 --> 00:40:00,980
is spinning and wobbling
a tiny bit,
723
00:40:00,982 --> 00:40:02,649
and that's fine for a little
demonstration like this.
724
00:40:02,651 --> 00:40:03,850
But if you got a train traveling
725
00:40:03,852 --> 00:40:05,351
at hundreds of kilometers
an hour along the track,
726
00:40:05,353 --> 00:40:06,820
you're going to need
a very, very sensitive
727
00:40:06,822 --> 00:40:09,622
and accurate feedback system.
728
00:40:17,932 --> 00:40:20,066
The Shanghai Maglev
729
00:40:20,068 --> 00:40:24,871
takes this simple concept
to a whole new level.
730
00:40:24,873 --> 00:40:30,810
There are 128 sensors in each
section of the Maglev vehicle.
731
00:40:30,812 --> 00:40:33,680
They feed back the distance
between magnets and track
732
00:40:33,682 --> 00:40:35,849
thousands of times a second.
733
00:40:38,052 --> 00:40:40,787
Powerful computers adjust
the electromagnet's current
734
00:40:40,789 --> 00:40:45,024
constantly
with microscopic accuracy.
735
00:40:45,026 --> 00:40:47,227
This is the guideway,
736
00:40:47,229 --> 00:40:52,298
and the train floats one
centimeter from the guideway.
737
00:40:52,300 --> 00:40:54,234
Now, that is incredible
precision.
738
00:40:54,236 --> 00:40:56,703
Now, there's a computer system
that makes sure
739
00:40:56,705 --> 00:40:58,838
that, all of the time,
the train floats
740
00:40:58,840 --> 00:41:02,308
at one centimeter
from the guideway.
741
00:41:06,313 --> 00:41:08,214
An advanced computer system
742
00:41:08,216 --> 00:41:10,450
regulates the operation
of the train service.
743
00:41:10,452 --> 00:41:13,786
Each journey's travel time
is predictable to the second.
744
00:41:13,788 --> 00:41:16,890
Now, this is
the ambition of the Maglev,
745
00:41:16,892 --> 00:41:18,558
with computer systems
746
00:41:18,560 --> 00:41:23,429
able to achieve
an extremely precise service.
747
00:41:35,943 --> 00:41:38,144
It's taken decades of planning,
748
00:41:38,146 --> 00:41:40,480
design, and testing to create
749
00:41:40,482 --> 00:41:44,784
the world's only commercially
operating high-speed Maglev.
750
00:41:49,256 --> 00:41:52,125
It's a unique concept that
throws away the rule book
751
00:41:52,127 --> 00:41:53,793
for traditional train travel
752
00:41:53,795 --> 00:41:58,731
and makes high-speed journeys
possible in engineless vehicles.
753
00:41:58,733 --> 00:42:02,168
A system like the Maglev
754
00:42:02,170 --> 00:42:05,505
points to the future of
transport in our world,
755
00:42:05,507 --> 00:42:08,074
incredible things
to be achieved.
756
00:42:08,076 --> 00:42:10,777
This shows us that
we can get people moving
757
00:42:10,779 --> 00:42:13,713
from "a" to "b" in short
periods of time,
758
00:42:13,715 --> 00:42:17,050
which is great.
759
00:42:19,119 --> 00:42:21,754
By drawing on
the innovations of the past,
760
00:42:21,756 --> 00:42:24,891
adapting, improving them,
761
00:42:24,893 --> 00:42:27,093
and making breakthroughs
of their own,
762
00:42:27,095 --> 00:42:28,761
the designers and engineers
763
00:42:28,763 --> 00:42:30,663
of the Shanghai Maglev
764
00:42:30,665 --> 00:42:33,666
have realized the dream
of a super-fast train
765
00:42:33,668 --> 00:42:35,501
that flies without wings
766
00:42:35,503 --> 00:42:40,006
and have succeeded in making
the impossible...
767
00:42:42,042 --> 00:42:44,978
Possible.
768
00:42:44,980 --> 00:42:47,981
It's kind of unbelievable
769
00:42:47,983 --> 00:42:52,318
that there's a train that goes
over 400 kilometers an hour.
770
00:42:52,320 --> 00:42:55,488
It is a vision of the future,
771
00:42:55,490 --> 00:42:57,223
and it's here right now.
59878
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