The Assassin (Sha ren zhe Tang Zhan)

Today on "Impossible Engineering"...

The international space station,

the largest structure ever built in space.

The engineering that's gone into the international space station,

it is phenomenal.

To create a base that's out of this world...

To see this amazing invention fly

into the international space station

is the most incredible thing I could possibly hope for.

Engineers must turn

to revolutionary innovations of the past...

Oh, my god, it's actually flying!

To make the impossible possible.

captions paid for by discovery communications

space exploration is entering a new era.

After decades of innovation, aerospace engineers

are preparing to send the first astronauts

to Mars and beyond.

And this giant leap could provide the key

to colonizing the galaxy.

And central to making this possible

is the International Space Station.

The International Space Station's hugely important

in the future of human space flight and exploration.

We have to master a number of things, though,

so we can go further into space.

For astronaut major Tim Peake,

his first visit was career-defining.

I had a huge "wow" moment when you look and see it

in all of its glory in the sunlight.

It is a marvel of human engineering.

Orbiting the planet every 90 minutes,

the $100 billion cosmic laboratory

is the largest human-made object in space.

Measuring over 320 feet end to end

and weighing around 450 tons,

it has the same habitable space as a Boeing 747.

Powered by over 32,000 square feet of solar arrays

and producing its own air and water,

the I.S.S. can host six astronauts in a completely

unique working environment.

And the interplanetary work being done here

has never been more crucial.

We're conducting research into how humans and robots interact.

This is going to be very important moving forward

for lunar missions and for our martian missions.

So, five plants from the top.

We're also growing food in space.

We're trying to learn how can we make

a closed life-support cycle.

This is the kind of research that's going to help us

with those future space exploration missions.

But as research intensifies,

so too must the journeys to the station.

And back on Earth, private aerospace engineers

like John Curry must overcome a specific problem.

The space shuttle was retired in 2011.

And when we lost the space-shuttle capability,

we lost a huge amount of capability

to service the space station.

To make the journey, astronauts must now travel

to Kazakhstan for a costly ride

aboard the Russian's Soyuz rocket.

So NASA is turning to the private-space-flight industry

for a more cost-effective approach.

Re-usability of hardware can play a really important role

in trying to reduce the cost

and improve access to space.

So, how do you build an inexpensive reusable spacecraft?

To do this, engineers must look to the pioneering

innovators of the past.

Space historian Amy Shira Teitel is exploring Edwards air force

base deep in California's

Mojave desert to discover the breakthrough engineering

that seemingly defies the laws of physics.

Oh, wow.

Okay, this is awesome.

Nicknamed "the flying bathtub,"

the M2-F1 was a prototype plane built in 1963.

If you look at, it doesn't look like it should be able to fly.

But in reality, it actually pioneered

a whole new way of flying.

American engineer Dale Reed designed this unusual aircraft.

Because of the high cost of disposable space capsules,

NASA wanted a reusable vehicle that could land on a runway.

But the wings of a traditional aircraft

would burn up during reentry from space.

So engineers had to completely rip up the aerodynamics handbook

and start again.

The shape of a conventional wing

is what gives an aircraft its lift.

As air flows over the curved top, it speeds up,

creating an area of low pressure

while airflow underneath remains constant.

This pressure difference between the two airflows produces lift.

But Reed got rid of the wings altogether.

And in April 1963, he tested a prototype that relied

on the turbulent airflow underneath the body,

hoping to generate lift.

Now, because the M2-F1 didn't have any motor,

he had to find an alternate power source...

A Pontiac Catalina.

The plan was to tow the lifting body behind the car

to see if it would actually generate lift.

So even though the vehicle itself doesn't have wings,

Reed hoped that because the body is shaped like a wing,

it would fly under the same principles.

During the original test,

the Catalina towed the M2-F1 across a dry lake bed.

All right, we're rolling.

And it's rolling, and that's exciting.

It looks like it's trying to nose up every so slightly.

Ooh!

Come on, come on!

It looks like it might get off the ground.

It's flying!

Oh, my god, it's actually flying!

I can't believe it actually got off the ground.

As the M2-F1 reached 86 miles-per-hour,

it lifted off the ground.

Although only by a small amount,

Reed's theory stood up to the test.

John Curry and his team

at the Sierra Nevada corporation in Colorado

are taking Reed's concept to a whole new level.

This design is one of the most incredible pieces of engineering

I have ever been lucky enough to be part of.

It is going to change the world of space transportation.

The all-new dream chaser is revolutionary.

This reusable lifting-body spaceplane will carry both cargo

and up to seven crew to the space station.

To make this epic journey,

it will launch on an atlas V rocket.

Once in space,

it will make the two-day voyage to the I.S.S.

Using it's own propulsion.

We use our thrusters to get us there.

Nitrous and propane, 22 of them that can both orient the vehicle

and can actually push the vehicle through space.

Wonderful capability.

But the return trip into the Earth's atmosphere

is where Reed's innovations come into play.

When you start in space, you're moving at 17,500 miles an hour.

As you go through the atmosphere now,

the dream chaser then is able to take

that 17,000 miles-per-hour

and absorb all that heat that the atmosphere creates

onto this shape

and protect the cargo and the crew inside the vehicle.

The wings here, they're just on the edges

and they're just providing the control

like sails on a sailship.

Whereas all the lift is being provided by the body itself.

And in October 2013, that theory is put into practice.

Engineers conduct a series of drop tests high above

the California desert.

Three, two, one, release release release.

When the dream chaser returns from its first mission in 2020,

this new spaceplane will touch down

using a unique nose skid landing system.

The great thing about the lifting-body design

is it does so well at the high altitudes

and then also does well at the low altitudes

such that we can touch down at about 200 miles-an-hour,

and then roll out to a wheel stop on any conventional runway.

Because of its transformative design,

each dream chaser will be used for at least 15 missions.

The opportunity for us to get to see this amazing invention fly

into space to the international space station

and back again is the most incredible thing

I could possibly hope for.

But to ensure regular cost-effective missions,

NASA needs more than one type of spacecraft.

And to design them safely, engineers must look to

the trailblazing innovators of the past...

Oh, my god!

It looks like it could potentially break his neck.

To produce more impossible engineering.

The international space station...

The largest structure built beyond Earth.

Travelling over 17,000 miles-per-hour,

this cosmic laboratory

orbits the world every 90 minutes,

providing a staging area for deep-space exploration.

Liftoff of Tim Kopra, Yuri Malenchenko,

and Timothy Peake.

That 8-minute 48-second ride into space

is just the most thrilling ride you could possibly imagine.

But with increased demand for travel to the I.S.S.,

cost-effective spacecraft are crucial.

And the American aerospace company Boeing

is rising the challenge.

Aerospace engineer Melanie Weber is helping to design

the company's first reusable space capsule.

The Boeing CST-100 starliner is a space-transportation system

which is comprised of a pressurized crew module

and a service module.

But unlike NASA's capsules that landed in the water,

the starliner will be the first U.S. crew module

to land on solid ground.