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So how does a General Electric
GEnx engine work?

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The GEnx engine specialties
are that only 10 percent of the air

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actually gets ignited with the fuel;

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the rest just gets blown out
of the back of the engine.

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Each engine is worth $34 million.

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That's as much as, probably,
two tons of gold.

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It is the most expensive kind of engine.

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I already said that.

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This engine is only used on two aircraft.

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It's the safest type of engine ever built.

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The engine's insides -

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I'll explain the parts
from the front to the back.

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So first, there's a sharp nose cone
on the front of the engine.

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This is to improve the aerodynamic
flow into the engine.

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This is to improve the aerodynamic
flow into the engine.

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Next are the fan blades.

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Each fan blade is made
out of four sheets of carbon fiber,

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a strong but lightweight material.

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It is also what the revolutionary
787 Dreamliner is made up of.

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Then there's a huge pipe-looking
cylinder called the housing.

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This part keeps the fan blades
from falling off

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and gives the engine its unique shape.

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Then there's the low pressure compressor.

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This part receives a short burst of air
from the fan blades,

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which drives the combustion fan.

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Then there's the high pressure compressor.

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It receives a massive burst of air
from the low pressure compressor

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to drive the low pressure turbine,
which I'll explain later.

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Then there's the compressor.

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This is where the fuel and the air
are mixed and ignited with each other

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to create forward motion
to the rest of the engine.

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Then there's the high pressure turbine.

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This is where the mixed air
gets blown into, to create -

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it sends forward motion
to the fan blades at the front.

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Then it also drives the fan blades
in the low pressure compressor,

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which forces the combusted air
into the rear cone and out the back.

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So how does the engine work?

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The engine works by sucking in air
through the front.

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It's compressed to 1/10 its original size.

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Then the air and the fuel
are mixed and ignited.

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This creates a small, controlled explosion

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that turns the fan blades in the turbines.

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And the mixed air
gets blasted out the back,

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which creates the forward motion
to the bigger fan blades,

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which shoves the uncompressed
air out the back.

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So why do we need this engine?

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Because it emits less greenhouse gases,

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it has reduced
the number of safety issues,

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it has saved a lot of fuel costs,

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and it's extremely quiet
compared to other engines.

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This engine is only used
on two types of aircraft:

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the 787 Dreamliner,

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the world's most luxurious
and advanced aircraft of the 21st century,

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and the 747-8, the world's largest
passenger airliner

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and the greenest too.

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Both are made by Boeing.

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But there are some problems.

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Even though this engine
is sending us in the right direction,

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there are a few drawbacks.

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It is extremely expensive to make,

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to build, and maintain.

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It still emits greenhouse gases,
but not as much as others.

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It is extremely easy to freeze up
or get too cold to produce thrust -

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and are easy to break
if not maintained for properly.

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Even though these problems are bad,
there are a lot of solutions.

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As one of my favorite inventors said -

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Wernher von Braun -

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"I've learned to use the word
'impossible' with great caution."

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So [we need] to create engines
that do not have any of these problems:

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engines that do not get too cold
to produce thrust or to freeze up,

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engines that are cheap
and easy to manufacture,

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engines that are really tough
and hard to break,

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and engines that have detailed
maintenance manuals with the construction.

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Have a safe and fun time flying.

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See you in the air.

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(Applause)