Original subtitles

A mission like no other.

A plane powered only by the sun.

Set to fly around the world without a drop of fuel.

What we do in the air, we can do on the ground.

And this is our message.

This journey will push the limits of technology.

It's made of fabric, it's made of carbon,

and you can break it with your finger.

It will test the endurance of its pilots.

Do something wrong,

just one thing, they could die,

and you carry that for your, for the rest of your life.

Flying solo day and night.

We never flew over the ocean.

Five nights in a row, that's the main challenge.

Switching on the solar generators.

They will risk their lives.

There's bad weather coming in

and then thunderstorms,

and afterwards it's turning northwest.

Either we divert,

or we take a big risk.

To realize a dream for our planet.

The decision we take

goes far beyond the flight itself.

"The Impossible Flight," right now on "NOVA."

"The Impossible Flight," right now on "NOVA."

To fly, fueled only by the power of the sun.

It's an audacious idea

that gave rise to an airplane unlike any other ever built,

now embarking on a revolutionary and risky mission.

The risk is really high.

I don't want to gamble with a pilot in the ocean.

A lot of people can be

a little bit afraid, scared,

by the unknown in which we are jumping.

A perilous journey, 26,000 miles around the world,

without a drop of fuel.

I think it's very dangerous.

You know, we never have the story of those who got killed.

We have to do it to demonstrate it works.

So someone has to do it first.

Someone has to try.

The zero-fuel flight begins in Abu Dhabi

in the United Arab Emirates,

where the sun's energy is in abundance

nearly every day of the year.

To have an airplane that could fly forever without fuel.

No noise, no pollution.

That was the dream from the beginning.

We can move up a little bit.

Just a little bit, just a little bit-- a little.

It was a dream that aviation experts quickly dismissed.

A solar plane capable of carrying a person

around the world

would have to be too big, too light,

and likely impossible to control.

There are moments where you have to take some risks

if you want to achieve something that has never been done.

Otherwise, we stay in the armchair,

and we wait until we're old and we do nothing.

We're in the early hours of the morning here.

The Solar Impulse 2 is ready to embark

on its ambitious round-the-world journey.

After weeks of flight tests over Abu Dhabi,

the airplane, known as Solar Impulse,

prepares for takeoff.

Over 3,000 miles away,

flight operations are run from a command center in Monaco.

Okay, André, everything is ready.

We still wait for the final go from the SRB.

The project is the brainchild of Bertrand Piccard,

psychiatrist, adventurer,

and heir to a family legacy of scientific exploration.

In 1969, I was 11,

and I saw Apollo 11 taking off to the moon.

And I said, "I want to have that type of life."

16 years I've been dreaming of that,

the art of flight around the world with no fuel.

There are doubts all the time, but...

When you're doing something that nobody has done before,

the doubts are important.

If you are on a straight line with your beliefs,

you never succeed in something new.

Solar Impulse from Solar Ground, confirm you get the clearance.

Okay, solar generator looks good.

Continue with engines, then.

Have a good flight, André.

Let's start the adventure.

Okay, finally.

It's the magic, magic moment.

Main wheel liftoff.

Thank you very much.

Currently altitude 5,300 feet.

To help make his dream a reality,

Bertrand turned to André Borschberg--

a man known for pushing boundaries,

both as a fighter pilot in the Swiss Air Force

and an engineer with a graduate degree from M.I.T.

The airplane was considered to be possible

to be built and flown.

The challenge is how?

I mean, to make something like this, huh?

Here is an airplane we designed, we dreamt about.

It's a big part of, part of me.

It's really a phenomenal sight, but crazy to believe

that it is just the sun powering that plane here...

Their dream is to show a way forward without fossil fuels

and spread a message about the need to fight climate change.

They are planning on about 12 flight legs.

With only one seat in the plane,

the pilots will have to take turns in the cockpit.

The most difficult will be the flights

over the world's two largest oceans,

lasting anywhere from three to five days.

At an average speed of just 45 miles an hour,

the 26,000-mile trip will be long and full of uncertainty.

Five months now, the plane,

starting this way,

if everything goes well, comes back this way in July.

It is so much more difficult

to use these clean technologies in the air

than to use them on the ground.

So if it works in the air,

I really hope people will understand

that they can replace all these old, polluting old stuff

by new, clean technologies.

What we do in the air we can do on the ground,

and this is our message.

When you fly with the sun as the only source of energy,

that's a completely different world, a different feeling.

The revolutionary plane

is powered by over 17,000 solar cells

that collect and transform the sun's rays into electricity.

That energy is distributed to four 17-horsepower engines,

each with the daily power output of a small motor scooter.

Any spare energy is stored in four lithium-polymer batteries,

which enable the plane to fly at night or under cloud cover.

The dilemma was how to build something

big enough to collect maximum sunlight,

but light enough to run on as little energy as possible.

The trade-off was instability in anything but perfect weather.

The plane is fragile and vulnerable to the elements.

Hello, André.

Below you, you have a small thermal inversion,

and below this thermal inversion,

you have all this dust and haze.

At mission control in Monaco,

a team of meteorologists, engineers,

and mission planners--

many of them also highly trained pilots--

monitors an array

of instrumentation and weather models

during flight.

You can put some more power...

Lead meteorologist Luc Trullemans

has guided long-range aviation and ballooning expeditions

across the globe.

But this mission presents a unique challenge.

This aircraft is so light, so fragile,

trying to find the places where he can fly

is not so easy.

When you have a downdraft or updrafts,

this aircraft can break in two.

Rain, humidity, and turbulence, forget it.

Only sun and quiet weather and tailwinds.

On this flight, they must steer clear of dust storms

and turbulence caused by heat rising off the desert.

Each flight leg will have its own difficulties,

like avoiding thunderstorms and crosswinds,

which could blow the plane off course.

We are excited, but there's a lot of fear, as well.

I think the overall round-the-world flight

you can compare to an Apollo mission.

If you do something wrong, just one thing, they could die,

and you carry that for your, for the rest of your life.

Two meters.

One meter.

The most dangerous part of every flight is the landing,

where the fragile wings are that much closer to the ground.

This pit stop in Muscat, Oman,

is just long enough to clean the dust off the solar wings

before the next leg to Ahmedabad, India.

The team back in Monaco plans on using high-altitude winds

to push the plane away from incoming clouds.

These thin and wispy cirrus clouds

could block a critical amount of sunlight.

For this 15-hour flight across the Arabian Sea,

Bertrand will take the controls.

Microphone and headphone,

and the cuffs-- when it starts to vibrate on your arm,

and this is to alert the pilot if the bank is too, too high.

With no heat in the cockpit,

the pilots must wear heated boots

and a sub-zero-rated parka.

Inside the cockpit, temperatures will range

from minus 4 degrees Fahrenheit

to 95 degrees when they descend during the summer heat.

Solar Impulse's ground crew readies the plane

to take off before sunrise to avoid turbulence

and stay one step ahead of the clouds.

When I was a child, I was afraid to climb in the tree.

Fear is there.

Either you have no fear at all,

which means you're completely crazy,

or you have some fear,

which means that you are not a daredevil.

It might not go well, but the only way to know is to try.

Solar Impulse-- Solar Control.

Bertrand's passion for exploration

has deep family roots.

What interests me the most

is not to break a record, but to do a first.

My father and my grandfather

were the first to the bottom of the ocean,

showing there was life in the deepest trenches.

The first in the stratosphere,

to see with his own eyes the curvature of the Earth.

When you do the first, you establish the first benchmark.

And from there, a lot of new things can come out.

I flew 20 days nonstop with a balloon.

Every day I was afraid to fall short of fuel.

And it was almost a failure.

We just succeeded because we had two hours of margin

with the propane after 20 days.

And that's when I made the promise

that I would fly around the world with no fuel.

Flying balloons is one thing.

Flying an experimental solar-powered plane

is quite another.

Bertrand only got his pilot's license in his 50s

and he couldn't have picked a more difficult airplane

to learn how to fly.

Because it is so big and light, it's particularly unwieldy.

Banking more than ten degrees

will throw the plane into a tailspin.

And because it's underpowered,

there's no quick way out of danger.

After 12 hours in flight,

as he approaches the airport in Ahmedabad,

Bertrand runs into trouble.

I have oscillations like hell.

It's crazy.

I never saw Solar Impulse do so unstable.

You said the aircraft is unstable,

and I don't see any turbulence at all.

It's unstable on the heading.

Did you see what happened just now?

Yeah, I see it.

It's a heading change of 15 degrees,

- without any problem from outside. - Yeah, yeah.

From what I see on the data,

it looks just perfectly calm.

Alarmed,

and puzzled by what's causing the problem,

mission control in Monaco sets up an emergency call with André,

who is already at the Ahmedabad airport.

There he is-- André, hello.

Bertrand started to say the aircraft is unstable,

and the autopilot cannot be connected

and had a few times sideslips of up to 15 degrees,

and he said it's...

15?

15, 1-5 degrees, and he said it's really hard to control.

Should we start looking for a helicopter

just in case?

I mean, first of all,

I think he should be ready to jump, right, yes?

Here we are looking for a bailout area

in the area he's flying for the moment.

If it's a pilot problem--

you know, pilot-induced oscillation,

I think we should take time, do everything very calm.

Unsure whether it's a problem with the plane or pilot error,

the mission team performs a series of handling checks

before landing.

No, now it's completely stable.

Okay

...because now I can keep the heading without the autopilot.

Okay, Bertrand, then the next thing,

I'd like you to extend the outriggers

and we slowly go down.

How was the flight?

It was fantastic flight.

Fantastic flight.

Any challenges or difficulties?

Always challenges with an experimental airplane.

You always discover, you always learn.

The bigger challenge lies ahead.

You have to cross the Pacific.

Are you looking up to that challenge?

Ah, yes, well,

it's going to be really impressive,

I tell you,

to cross the Pacific, to cross the Atlantic.

It's not done yet.

You can imagine that?

It's not done yet.

This plane has the capacity to take the rays of the sun.

I got the chance to see this plane,

and it's a once-in-a-lifetime moment.

Wow.

After each flight

the plane must be meticulously cleaned and inspected.

Even minor damage could pose a serious threat.

I think it's enough.

We had a little delamination on one of the solar panels.

No, don't push too much.

No, it's perfect.

This white spot can overheat one of these individual cells.

If one cell gets damaged,

like with the light bulbs in a Christmas tree,

you break down all the others, as well.

To build the "impossible plane"

required some unconventional thinking.

André pulled together a diverse team of engineers

from aerospace, Formula One racing,

even elevator manufacturing.

A lot of time where we thought

it would be impossible to finish the project--

it's too crazy, it's too hard.

Over 13 years of design and testing,

weight was the archenemy for lead designer Peter Frei.

I just knew from the beginning

that it must be a super-light aircraft.

13 years ago, the thrill, "Wow, is it possible?

Is it not possible?"

And it was an up and down,

you know, fighting, success, failures.

What they ultimately came up with

was a plane with a structure that's ten times lighter

than the best gliders.

More than 17,000 solar cells, each as thin as a human hair,

make up the top surface of the wing and fuselage.

These lightweight, flexible cells

store nearly 50% more sunlight

than solar panels on average homes.

They built a skeletal structure that was largely hollow,

like the bones of a bird,

using carbon fiber three times lighter than paper.

But there was one major design hurdle they'd have to overcome.

Know exactly the capacity of a battery,

it's a really difficult story, not only for us,

for everybody who tries to implement batteries

in a car or in a bicycle or something.

To store enough energy

to keep the plane aloft through the night,

they calculated that the four batteries

would weigh nearly 1,500 pounds--

a quarter of the plane's total weight.

So every other component on board had to be lightweight

and extremely energy-efficient.

The efficiency of the electric motors, we have 97%.

Only three percent of losses,

and if you compare this with a piston engine--

the efficiency of the system

is between 30%, 40%, maybe 45%.

The engineers, the team, has done an incredible job.

I mean, that's a Swiss watch of a size of a 747.

With far fewer moving parts

than an internal combustion engine,

the four electric engines lose very little energy through heat

and generate almost no friction.

Like a smart grid,

the network of solar cells connects

to the four motors and batteries sitting behind the propellers.

The cells capture the sun's energy

and convert it into electricity,

which flows through the grid to power the engines.

Any excess charges the batteries.

We charge the batteries in nine to ten hours

and we extract the energy in eight to nine hours.

So this is a very low rate,

and that's why we have losses

in the region of one to two percent.

But with a power output only slightly more

than the Wright brothers' first plane,

the aircraft teeters right on the edge of flight.

Failure is a real possibility,

especially on the multi-day solo flights over the oceans.

And both pilots had to train for the worst-case scenario.

We never flew over the ocean five nights in a row.

That's the main challenge.

The last measure we can take is to bail out,

but of course you want to bail out

when you really have to bail out.

If you do this mission, you have to be on the positive side,

or you will never do it.

Building the airplane, I think I'm realizing a dream

I had when I was really a little boy,

thinking about these pilots who were discovering aviation,

these pioneers.

I met Bertrand at the right moment with a great idea.

Radar from Hotel-Bravo-Sierra- India-Bravo, good morning.

I always have been a little bit rebellious against authority.

I left home when I was quite young.

What I learned as a fighter pilot which was useful,

I think you are trained to better appreciate the risk,

can come up with the right decision.

But decisions are made on the ground,

as well as in the air.

To find the best possible route around the world,

the mission control team pores over computer models

and global satellite data.

I am working on this since five years,

so I was watching all the airports.

There we have less rain,

less windy conditions, less cloudy conditions.

That's the reason that we will fly around the world

in a tropical area during the dry season.

Their route follows a broad tropical band around the Earth--

between the monsoons to the south

and cold storm fronts in the north.

After leapfrogging across India to Myanmar,

the plan is to get to China

in time to make their first ocean crossing in early summer,

when the hours of sunlight are reaching their peak.

But no matter how much they map out beforehand,

the pilots must be ready to change course

at a moment's notice.

In places like Mandalay in Myanmar,

the problem is that a hangar big enough to house the plane

isn't easy to come by.

So the team has to be self-sufficient.

They came up with a waterproof, windproof mobile hangar

that inflates like a giant bouncy castle.

This 7,000-pound shelter

takes the 20-person ground crew five hours to set up.

On the ground, the aircraft has a lot of weak point.

It is big, it is light, and therefore it is fragile.

It's made of fabric,

it's made of carbon, and you can break it with your finger.

The five-day, solo Pacific flight

will be the ultimate test,

not just for the experimental airplane,

but also for the pilots.

If successful, it would beat the existing world record

in any plane by nearly two days.

Five minutes before departure.

Okay.

In the lead-up to the mission,

the pilots spent three straight days

crammed in a flight simulator.

While doctors monitored their brain waves and vital signs,

they performed mental vigilance and stress tests.

The long duration of the ocean flights is a concern

for mission director and veteran pilot Raymond Clerc.

Shut down engine number two and...

And wait.

This operation is really pushing

the human performance to the limits.

The airline pilots, they fly always two in the cockpits.

You know, the normal flights, they last already 12 hours,

and they can sleep during the flight.

Our pilots, they don't have this chance.

Because they'll be alone,

the pilots can't risk falling into a deep sleep,

which would make them too groggy to take over the controls

in an emergency.

So the pilots practice a resting technique

used by the military and NASA:

20-minute cat naps throughout the day,

adding up to around three hours of sleep every 24 hours.

Now in Myanmar, it's nearly a month into their journey,

and they are halfway across Asia.

These shorter-duration flights serve as the final test

as they get closer to the first ocean crossing.

But first, Solar Impulse's safety review board

must make a final call on which pilot

will fly the critical leg to Hawaii.

Bertrand's difficulty flying at night

on his first flight to India

raises doubts about his readiness

during a mission control debrief meeting in Monaco.

Now, Bertrand, I really would like to have more details

on this phase before landing in Ahmedabad-- what happened there,

because, you know, we had really some stressed situation

on the ground.

I made a mistake in flying the plane in an unstable way,

and I really scared everybody,

so I was really, I was very embarrassed.

Not being prepared good enough.

Pilot condition must be better than what it was.

Now, of course,

I don't have the same reactions

than a jet plane pilot, so you also need to understand...

No, which is not necessarily a bad thing.

While in Myanmar, the safety review board ultimately decides

that Bertrand needs more training

before making an ocean crossing.

André is chosen to pilot the dangerous flight to Hawaii.

I was extremely disappointed not to make the Pacific.

That was my dream from the beginning.

I think I underestimated the difficulty to fly it.

On this airplane, it's not like in a normal airplane.

You have to be really more precise.

I initiated the project to fly in that airplane,

but then the same time, it's true I'm not the best pilot.

I'm the explorer who became a pilot.

I had to learn to fly that airplane.

And it's not easy for me.

This decision was extremely difficult for everybody, huh?

Especially when there are a lot of emotions

and, and so much at stake.

If I would do the Pacific,

I knew that I had to prepare myself very well.

When I will be in this cockpit,

there will be moments when it will be too intense.

We will sleep, but for very short time

of 20 minutes' resting period.

Yoga, meditation, breathing,

it's a way to reboot the system, which is start to be congested.

When you fly jet fighters,

you have whatever power you need to go against the winds,

to fly in turbulence and bad weather.

Here, it's just the other way around.

This airplane is like a leaf pushed around by the wind.

You have to make nature as a partner, and not as an enemy.

I think that's an attitude in life.

In some ways, I discovered when flying this airplane.

From Mandalay, Solar Impulse moves on to Chongqing, China--

one of the largest and fastest- growing cities in the world.

People say there is too much pollution,

there is climate change,

but it's not enough to complain about problems.

We have to bring solutions.

The same technologies

that can make an airplane fly day and night with no fuel

can be used to divide by two the emissions of CO2.

After seeing this, I think in my future, my future job,

maybe I will do something like this.

We have to think about our children, our grandchildren.

This thing is for them.

With Solar Impulse, we are only at the first phase.

Our goal is not to transport passengers.

Our goal is to transport a message.

With André, we've done six legs from Abu Dhabi to here.

Now it's time to go to the next level, and it's the ocean.

This is why Solar Impulse is built.

It's five days and five nights, solo flights over water.

It's like going to the moon.

Everything is under control,

but you still have to go to the moon.

The challenge with the solar energy

is to fly through the night.

The energy of the airplane is the critical factor.

During the day, we climb very high altitudes,

but we collect energy directly from the sun.

And we use this altitude at the beginning of the night

to slowly fly down-- this saves the batteries.

Minimum battery charge is-- if everything goes on plan--

is not more than ten percent in the morning at sunrise.

It's about an hour.

So there is not much margin, huh?

To conserve energy, the wings are designed for maximum lift,

and to create a high glide ratio and low sink rate.

If the engines were turned off at 28,000 feet,

a jumbo jet would glide for 20 minutes,

compared to four or five hours for Solar Impulse.

They had to thread the needle of aerodynamic design.

The larger the wingspan, the more energy they capture,

but the more unstable the plane is in choppy weather.

But if the wingspan were just ten percent smaller,

they might not have enough energy to make it to sunrise.

Everything okay there?

Okay, let's move forward.

We are removing each gram that we can in this airplane,

because each gram of course is consuming energy.

I did the most weight saving

because I lost four kilos during the last four months there,

so I did my contribution, huh.

We were never able to prove that the airplane

can fly through the night, so far,

and reducing weight is reducing risk.

The lighter you are, the further you get.

Who knows?

I mean, maybe this is the minute which counts.

Yeah, exactly.

The Pacific is the largest ocean on the Earth.

It's something that is always moving,

developing, dying, depressions, typhoons.

It's like a soup.

Since Solar Impulse must climb over 25,000 feet each day,

the weather team has to forecast 16 different layers

of wind, humidity, and temperature.

The most difficult part of this Pacific flight to Hawaii

is the crossing of a classical cold front

that acts like a wall--

cloudiness that gives precipitation,

so all things that you have to avoid.

And we have to find a hole in that frontal system.

Every day, we are looking for a hole there.

We're even dreaming about a hole.

The hard part is that after three days,

the reliability of their forecast drops below 70%.

Flying to Hawaii takes five, maybe six days.

When you cross that front, you have to be sure about details.

And five days ahead,

it's difficult, it's difficult to say.

Weather is posing a big problem

for the Solar Impulse plane...

The Solar Impulse has been grounded in China

due to bad weather brewing over the Pacific Ocean.

Simon, the white.

If it happens that you have bad weather,

pilot tired, and technology problem,

there is the biggest risk we have.

You dream of it almost all night,

because if there is a failure, there is a person in there.

So from the alt to end...

It's not only that we have the risk of losing the pilot,

but it will also change the life of every engineer,

which André maybe doesn't realize all the time.

Yes, I can hear you, loud and clear.

Yes.

How much, how much?

The closer we get now, more intense it is.

How much, how much?

The first time I will fall asleep will be over the ocean.

We all know that falling asleep when you are stressed,

not easy, huh?

I mean, of course, if I end up in the water,

it will be a shame,

but I'm ready for a lot of things to happen.

There will be moment of actions,

there will be moment of reflection.

I hope not moment of regret.

This inner voyage is really what I'm looking for--

to go through these different experiences.

This is the gift of all that.

You put breaking news, take-off tonight.

Starting to be exciting.

Finally.

I'm getting emotional a little bit.

Sorry.

I'm so happy.

Do we have a good corridor to get to the hole,

or we do not have a good corridor to get to the hole?

The hole's still there, yes, it is there.

It's more or less confirmed.

But a few hours later, there is a change.

Take-off, we have cirrocumulus which are new.

They were not seen before.

High-altitude clouds that block sunlight

have moved in around Nanjing

and will reduce their energy right from the start.

That front, that hole is moving a little bit to the east.

I think, yeah?

On top of that, tailwinds are decreasing.

The flight is getting longer,

and they'll have to cross the cold front

later in their journey,

when the forecast is less certain.

What's the flight time?

Flight time is six days and a half.

Six plus.

Having a seventh day, it's not acceptable for me.

If it's five-and-a-half, okay, on the edge.

But if it's six and something, it's-- oh.

- I - mean, if I look at everything now,

I have the impression

we are pushing a little bit too far there.

We are at seven hours from departure.

It's tight there, it's tight.

And uncertainty due to energy.

We have too many issues, that's the problem.

We have too many issues now.

Game over.

After working around the clock for days on end,

it's a huge blow to the team.

They are exhausted, but they must keep going.

The guys fighting each other because they are nervous,

they are under tension, they are tired.

If it's the window of the year, we just have to do it.

We're not going to do it for tomorrow.

I'm sorry, huh, but I think we'll not have a solution

for tomorrow evening.

The time to prepare a distance of such a huge window,

the weather maps and so on, it's not done in three hours.

He's tired, he's tired.

They are tired.

Don't forget that the distance from Nanjing to Hawaii

is almost two times Europe, and then you're asking us,

"What's the clouds going to be like in Poland

and in Greece and in Ukraine?"

In three hours? With two people!

I mean... I like my job.

I like my job.

But?

But it was hell.

I would prefer that we take some rest,

and tomorrow morning we start to fight for the next one.

Fresh and rested.

It worries me very much.

If you look in the history of exploration,

most of the big attempts have failed several times

before the success.

While the flight team waits in Nanjing,

temperatures inside the hangar reach around 100 degrees.

Lead engineer Robbi Fraefel is using portable air conditioners

and jerry-rigged tubing

to pump cold air into the battery compartments.

Inside each of the four custom- built lithium-polymer batteries

are 70 individual cells,

laid out like squares of a chocolate bar,

where the chemical reactions take place.

The cells are similar to those used in mobile phones,

but their chemistry has been optimized to boost performance.

The challenge with batteries

is that they rely on chemical reactions,

which are sensitive to temperature.

A battery likes to stay always

in the same temperature, same pressure,

and if we change both all the time,

it's not good for the battery.

With every ten degrees higher temperature,

the aging is about double.

So it makes quite a difference.

Only the Pacific flight will show the truth.

All right.

Working day and night shifts at mission control,

they struggle to find a way through the front,

running hundreds of computer simulations

to come up with the best course.

In the simulation, you play with the aircraft,

you play with the possibilities of flight,

like if it was a game.

There are many variables to take into account:

weather, air traffic restrictions,

and energy demands of both the plane and the pilot.

From one simulation to another one you see things are moving,

so it's not good.

After a month of striking out,

the weather team finally sees their chance.

There's a weak cold front five days out,

but the team is confident that the plane can cross it.

Is this now what we were dreaming of?

We will have a nice corridor

behind this system out to the ocean.

Three, even four days flying in sunshine.

Now it's the moment of truth.

The first time that this airplane

will fly with such a long time.

Okay, we move.

For the time being, looking good.

With nothing but open ocean ahead of him,

André will face 120 hours alone in the cockpit--

longer than any human has sustained before.

He's doing this really with a lot of his heart

and all his being.

I don't think anything else matters.

The Solar Impulse 2 plane

is currently tackling the most ambitious leg

of its round-the-world journey.

Once midway across the Pacific, there's no turning back,

with no airports to land at

and no boat capable of trailing the plane fast enough.

Even to get one man across an ocean

will push him and his machine to the limits.

We have now entered the first really critical part

of the flight.

He is now starting to reduce the power of the engines.

He starts to glide down,

and he needs to save his energy as much as he can

until the next sunrise.

During the night, André will slowly descend,

relying on the potential energy he gained from altitude,

and the plane's highly efficient glide.

But at dawn, they'll be down to their last energy reserves.

Just a thin layer of clouds

could throw a wrench into all their energy calculations.

And if André comes up short,

his only option is the inflatable raft under his seat

and the hope that his GPS beacon

will guide a passing ship to his rescue.

Wednesday there is bad weather coming in, thunderstorms,

and afterwards it's turning northwest.

It's a...

It's a wall in front of us?

And we have one or two layers

where we have stratocumulus.

We will reach the point of no return

in approximately ten hours,

so we have to have a decision by that point.

They are fast approaching the point

at which they can no longer turn back

because of the prevailing winds.

The good side is that the plane flies well,

André is in a good shape,

and probably we can make it through the first night

with enough energy.

On the other hand, we're in deep,

because we don't know how to cross the bad weather front

in five days.

It's a big deception, actually.

The problem is that cold front over the ocean.

And at take-off, we were confident

we had solutions to cross it,

and then we didn't have a solution anymore.

André has now made it through his first night,

but the cold front predicted for day five

appears to be intensifying and becoming more hazardous.

So you can confirm that it's blocked now.

At that position, yes. At that position, yeah.

The updated weather models

now show that there is no clear passage

through the cold front.

André would have to descend

through multiple layers of cumulus clouds,

which likely contain moisture

and will produce turbulence-- a dangerous one-two punch.

The aircraft is going through all those clouds,

not close, you know, with layers.

But turning back to land also carries its own risks.

Japan is their best option to divert,

but they have no logistics in place for an unplanned landing.

André is in a holding pattern over the Sea of Japan--

as they negotiate with several potential airports.

Well, for me, it's clearly red to continue.

It's no way.

The earlier we announce this diversion,

the higher is the rate of success, I would say,

to save the airplane and the pilot and the mission.

My personal opinion is that we have more risk

of losing the airplane in Japan

than if we try to reach Hawaii.

I don't see how we can get permission

to inflate a mobile hangar in Japan.

The airplane is not made

to cross a front and fly in cumulus clouds.

Until when can we still say we try to cross?

Now.

Either we divert

or we take a big risk.

Nobody is confident to continue,

so our position would be

to make a diversion on Nagoya.

If no window,

no go.

The green energy plane, Solar Impulse 2, stopped moving

towards its make-or-break next destination, Hawaii.

There's no telling how long they're going

to spend in Japan waiting on the weather conditions.

It is an unwelcome diversion.

A small emergency crew is now in Nagoya with the mobile hangar,

but they don't have enough people to set it up.

And the forecast calls for rain and heavy winds.

We need to be able to get the mobile hangar assembled tonight.

If we did not succeed,

the risk is that we lose the airplane completely,

and the risk is extremely high.

It's not a ten percent chance, it's 90.

Well, what we need now is our hangar, you know,

to prevent it from sun, wind, and rain.

We're pretty much struggling to keep it on the ground.

We need to put full speed on it.

Maximum speed, maximum efforts.

Just ahead of the rain, the rest of the ground crew

finally arrives and jumps into action.

Un, deux, trois!

The aircraft was not just a little bit wet,

it was completely wet,

with water dripping from every single part of this aircraft.

Well, we want to avoid a short circuit,

because that would blow very probably the main fuse

inside the battery.

Oh.

I didn't see that.

I hope it will be okay, but I don't know at this stage.

Maybe in three months we're still in Japan,

and then it would be a disaster for our flight around the world.

The team is grounded in Nagoya for over a week

to fix the wing spar that broke in the heavy wind

and ensure the airplane is completely dry.

Checking if there is a little bit of water

left in the structure.

Parts which have water inside explode

if the water gets frozen when we climb very high.

André would take all the risks.

Yes.

We from the engineering,

we want to reduce as much as we can to make his life safe,

but he is a risky guy.

No panic, no panic, no panic.

Meanwhile, at mission control,

the diversion to Japan poses a problem

for the air traffic control specialists on the team:

a crowded airspace with many restrictions,

which they have to negotiate.

Flying at 35 knots

in the midst of traffic which flies at 500 knots.

So it's a little bit an obstacle, huh?

The Japanese insist that Solar Impulse

avoid red zones of peak air traffic and militarized areas,

limiting their exit strategy.

We always want to wait for better windows,

but now we have passed the 21st of June,

and it's going to be worse and worse in term of energy.

We are not on the safe side if we wait.

In preparation for take-off,

the ground crew begins taking apart the mobile hangar

as the press stands by.

But the forecast takes an unexpected turn for the worse.

There is no high pressure there.

It's complete weather.

There is absolutely no way to go through.

To follow something

for three days,

and ten minutes before the take-off.

Crazy.

It was a bit...

There's a really a problem somewhere

in our way of working.

Okay.

We're checking if we should proceed or not.

How are you feeling?

Detached.

That's the best way.

I think we really need it now,

because the spirits are sort of not very well.

And if we now take the plane back,

assemble the mobile hangar again, and stay here for longer,

it's going to be quite bad

for the general mood of the team, I think.

So that's why I believe we're going to take off.

It's going to happen.

This afternoon I was confident.

Now I feel more like gambling.

And if he has to bail out here, okay.

The water's maybe already warmer,

but I don't want to gamble with a pilot in the ocean.

I'm not confident to letting, taking the risk of your life.

It's very difficult

to go against the inner, inner feeling.

There are two terrible situations.

The worst is to be in the middle of the Pacific

and see that it closes,

and to lose the plane and you jump.

The other one is to be on the runway

and to see that it closes, and this is exactly what we have,

but it's not as bad as if you are

in the middle of the Pacific.

I feel that you went over the tipping point

in terms of feeling, and so it must be right.

But it's a terrible situation, and I imagine for you...

I'm so sorry for you, André.

You... you cannot imagine...

Don't be sorry, huh?

You cannot imagine how sorry I am for you.

You are in that cockpit, you are ready to go.

When I said we have to stop, Michael told me, "Thank you."

Yeah.

So confirm, flight is canceled.

We go back to the tents, unfortunately,

but that's-- that's life, huh?

A lot of hurdles.

Big hurdles.

We tried everything we could.

And we, we just...

We just failed the last centimeter.

The last centimeter.

Always trying to make it, to make it work,

and then you see that all that work is kind of for nothing.

I have to admit that the last weeks, I was...

I was losing, losing faith.

With the Summer Solstice now behind them,

the daylight hours and available energy to cross the Pacific

are steadily decreasing.

The monsoon is really picking up here in Japan,

which means rain, it's also the risk of a typhoon.

So what we are facing if we cannot leave

over the next few days to Hawaii

is being hit by a typhoon, lose the mobile hangar,

and of course, lose the airplane.

We will always have an unknown thing.

I think this is the nature of a forecast.

It's a forecast, it's not the truth, yeah?

Either we try to cross an ocean or not.

At last, it looks as though they can.

A promising five-day window of clear weather opens up

from Nagoya to Hawaii.

You know, it was so embarrassing to have André ready to take off,

all the press watching,

we had to cancel at the last minute.

And this time we want to avoid this.

So we're not telling anybody.

And once we're in the air, if it works,

then we say, "Hey-O, coco, here we are.

This time it's going well."

Okay.

Third attempt, ladies and gentlemen.

Third time that we try to move.

Whatever happens, we go.

I am committed.

Completely committed to this flight.

Point of no return is already passed long time ago.

Friday, we were both super-, super-depressed in Tokyo.

This might be the end.

And I'm, it's not sure we're going to still make it,

but if we make it to Hawaii,

at least we've done the hard thing.

We are just getting ready,

and we try to take off at 3:00 a.m. sharp.

This time it seems better, so we try again.

Looking fine from Nils.

Go to standby now.

Then, just minutes after take-off, they hit a snag,

this time with the plane's autopilot surveillance system,

known as the M.A.S.

There was a short M.A.S. failure.

Okay, copy.

There was a short M.A.S. fail.

If we do not find out why it happened or what triggered it,

we should not continue for the Pacific.

The biggest concern is...

The problem is the M.A.S.

That's the, that's the killer one.

The M.A.S. is the system

controlling the autopilot,

which is giving false alarms and waking up André

each time he wants to sleep.

The M.A.S. wakes up André if there is a significant change

in the airplane's heading or bank angle.

The false alarms are not just annoying,

they keep André from getting the rest he needs.

If the system fails completely,

he will have to rely on mission control to wake him up.

But there's a chance he could lose satellite communication

out in the middle of the Pacific.

So you want to continue to Hawaii?

Yeah.

Knowing that the monitoring is not working?

Yeah.

And you still... you...

It makes life a little bit more complicated.

We'll need monitoring from the ground.

The risk is really high.

The risk is really, really high.

We have 55 minutes before the point of no return,

and we don't know what is causing this,

and we have no idea.

I mean, it could degrade.

We still don't know the cause of the problem.

No.

If we go back to Nagoya,

I'm sure we would find another window,

but the season is not over.

A bloody situation.

If we go back to Japan,

I think it's the end of the project.

With the electronics malfunctioning,

the engineers have serious concerns about continuing.

But the pilots are concerned

about what another aborted flight could mean

to the future of the project.

Now we just need to know if André wants to continue or not.

And what do you think it will take for him to decide?

Guts.

Not only as a pilot, but for the project.

It's the most serious crisis they have faced,

leading to a sharp division within the team.

- We have an aircraft, which is not nominal. - Yeah.

Things will break during this journey,

and if we start the journey

already with one redundancy down,

that's not a good starting basis.

I would recommend to go back.

Going back to Nagoya

in the season of typhoons

with the possibility of destroying the airplane

on the ground,

in term of overall project,

it's more risky to come back than to continue.

Personally, I have a very good feeling I can do it.

We have an airplane which has a very good source of energy.

Very good storage.

If you decide to continue, as a friend,

you have all of my support,

but as an engineer,

I would say we have to go back as we have the choice.

A lot of people can be a little bit

afraid, scared,

by the, by the unknown in which we're jumping.

I was very often in my life

in these type of situations,

and I tell you it's worth it.

But the decision we take goes far beyond

the flight itself.

We have now the possibility

to do what nobody has done.

When Chuck Yeager

broke the speed of sound, he had a broken rib.

All these things were absolutely incredible feats.

I think it's very dangerous, too, with this heroic speech

to encourage people to take a wrong decision

because we never have the story of those who got killed.

This is a hard project.

These are difficult situations.

I guess I do it because I do this airplane quite well,

and what can be done and what cannot be done.

Nobody in the future will understand

that two managers can go against a whole team,

and you really force us to support something

that nobody wants to do.

I just want to make one point very clear.

There's only so much we can do to support you

from here, from the ground.

So when you decide to go on,

you will be on your own up there.

This is Capcom speaking.

We have to start the climb now if we want to have a chance

to respect the profile.

Go!

Climb!

From an engineering point of view,

it was the wrong decision.

That you still can make it is, like, I don't know,

driving with a flat tire.

We have to be lucky, from a certain point of view.

But it's...

It's their decision.

We saved the project by deciding not to return to Japan.

On the other hand, we have some of the engineers

who are so pissed off

because we did not follow their recommendation.

They want to leave the project,

and I don't know what will happen after Hawaii.

As morning comes,

André continues to be awakened by false alarms.

So I lost one source of information.

Well, let's see,

we are currently rebooting.

A lot of wake-up calls in this, in this airplane.

This M.A.S. system, which monitors the aircraft

while the pilot is resting, is behaving erratic.

We had it working

in the beginning,

then it produced a failure, so we shut it down.

We tried again.

We don't really know what the status of the system is.

The first night was about digesting,

I mean, the emotion of the first day.

It was really intense.

When I look out, you know, I see the moon,

I see the clouds, and here I am over the Pacific.

I think a feel a bit higher.

On day two, there's a worrying new development--

the plane's batteries are overheating.

We need to burn more energy.

It is a risky game to...

I know.

Due to the flight profile we did on the first day,

the batteries got too warm.

If it sums up over the days, it can become really too hot.

They can start to burn.

Climbing too quickly on the first day

increased the demand on the batteries,

and they began to overheat.

The risk is that this could degrade their performance.

Today the challenge

is to keep the battery temperatures low,

as low as possible.

So we will adjust the climb profile

to not have too much current going into the batteries.

It's turbulent since I think about one hour.

We are climbing again at 9-0, and we'll see if it's better,

but it costs energy.

That's exactly what I was afraid of.

Still some time until the next sunrise.

Turbulences during the night, which means a lot of work,

of course no auto-pilot, of course no sleep.

I really started to work hard to see how we could get out.

So we climbed again, and when you climb,

you use the energy that you need for the night

so it's a little bit stressful.

We're monitoring everyday

how many resting periods is he getting.

For the first two nights, he had three hours of sleep.

That's okay,

but we don't know what's going to happen

on day four if you keep that rhythm,

and day five.

So we climb every day the equivalent of sea level

straight up to Mt. Everest.

No acclimatization.

If you don't have enough oxygen,

there's the risk of hypoxia.

Within 60 seconds,

will lead to a severe degradation

in your ability to understand what's going on around you.

You become euphoric.

So not only are you in a dangerous situation,

you're not able to recognize the situation

and you feel good about not recognizing the situation.

Then very quickly you will pass out.

We're watching to see how his body is absorbing the oxygen.

Is it actually getting enough?

You're constantly listening to this...

You hold your breath.

And hope he breathes.

And then you keep going.

Pilot status.

Mood, he is exhausted.

Not as good as it was.

We have a pilot that is starting to show signs of fatigue.

We have batteries that will not take a lot more abuse.

We see that all the systems are stressed, yeah?

The flight is not over.

Quite intense.

You have to perform because it's real-time, you know.

As an engineer, you are used to,

"Okay, I solved the equation today,

"and if I don't solve it today,

then I'm going to solve it tomorrow."

And this is totally different.

I'm kind of happy that it's soon over.

So now a preparation for landing.

I was thinking about all this, and I cried.

Cried loud.

It was a little bit ridiculous, you know,

alone in the cockpit crying, everything was going well,

but it was so, so intense.

And André,

you have some kind of headache?

No, not headache,

but something has been growing on my head.

Really strange.

Okay, but I cannot see it.

Do you have the face view?

And now-- oh, okay.

He looks terrific, yeah.

I don't know what happened.

I spent too much time in this damned plane.

Ça va bien, ça va bien.

He can feel every, I think, element in the plane.

He knows which wings is vibrating.

I think he was a bird in another life.

A plane powered only by sunlight

makes history today

in a five-day journey across the Pacific.

This will be the furthest a solar plane has ever flown,

as well as the longest-lasting solo flight in aviation history.

I've never been to something

this historical before.

Too young to see other things,

just the right age to see this.

It's absolutely beautiful,

and the latest wind from the ground crew is 0-4-0-3 knots,

in the axis.

Okay.

To confirm, you have the landing and promotion lights on.

It's nice to put them on.

Yippy!

Flight path secure.

André!

To fly with the sun,

you need to be extremely energy-efficient.

And this efficiency can be used everywhere.

This is why it's a historic first for aviation,

and a historic first for renewable energies.

Will you make it around the world?

Are you confident of that?

It's an attempt.

We cannot be overconfident.

I received so much support from people I didn't know,

and the beautiful message.

So when you read this, you know,

you know that people are supporting you.

And I was carried by all this, I'm sure.

All of us were very lucky to have the pilot back,

but when this decision came up that André and Bertrand

want to continue,

it hurt us in the soul that somebody decided against us.

I was fully in opposition to André and Bertrand.

André is pushing.

We always had these discussions and fights,

"Why do you tend to go beyond limits all the time?

"We, engineers, tried to set reasonable limits

"that you survive,

"and you, your target is always

to sort of prove us that we set the limits too narrow."

If everybody is telling you that you are a hero,

I think it's good also for them that there are people

who try to pull them back and on the ground from time to time.

Despite the divisions and problems with the plane,

they are still hoping to get around the world this year.

Their immediate worry is the health of the batteries.

The concern about the batteries is that they are damaged.

We heated up the battery in only one hour by about 20 degrees.

At the moment,

we are on the worst-case scenario

where we have to exchange some cells in the batteries,

which is... this is a nightmare.

We have overheated the batteries.

More cells are damaged than the spare parts we have,

so the logical consequence

is that we will stay here until next April

where we can continue.

The flight from Japan to Hawaii

left scars on many of the engineers.

I think, for everybody,

to complete this flight around the world

is extremely important.

It's part of their life.

I mean, they all stayed.

During the break, new batteries had to be manufactured in Korea.

The engineers realized that the batteries were over-insulated

against the cold

and heating up too much in warm conditions.

So they engineered a two-way valve system

that allows the pilot to let the heat out.

Last year, I was too much emotionally involved.

Ça, c'est bon.

I was thinking, "It's now or never."

I was completely the head under the water,

which is really not good

for flying an airplane over oceans, you know?

I've flown 20 days in a balloon, but we were two.

Flying alone, it's something different.

To prove he could fly safely over several nights,

Bertrand trained to rely more on instruments

than on the horizon.

One, two, three, the fourth one.

I will never be as precise as a jet fighter pilot.

This you cannot get at my age, but at least to do it correctly.

Climb 174.

After studying potential routes from Vancouver to Mexico,

the team locks in on a three-day flight path to Moffett Field,

home of NASA, just south of San Francisco.

We see a weather window for Moffett right now.

It looks good, it's a short flight.

Okay?

We'll only confirm really tomorrow,

even on the day of take-off.

It comes from the house of Charles Lindbergh, in Maui.

A beautiful gift.

This is more for the Americans than for the Europeans,

and it's "Star Trek," Captain Picard,

who is inspired from the twin brother of my grandfather.

It was a challenge to be an explorer

that would be different

than my father and my grandfather,

not to just redo the same.

The wind is at the limit,

so for the time being, we don't go out.

I was doubting sometime, is it my way?

Because I'm also interested by psychology, spirituality.

Good Morning, Bertrand.

This is Christophe.

How are you?

I'm fine.

I had four hours of good sleep.

I woke up before the alarm clock.

I'm in perfect shape.

Very good, very good.

My father and my grandfather gave me the drive

to be an explorer,

but my mother showed me the need to give it meaning.

We were extremely close,

like two human beings in quest of understanding

why we were on this Earth.

Wonderful.

Have a great flight, Bertrand, and enjoy it!

And don't forget to come down!

People are always thinking, I am the wife,

I should have this fear.

When Bertrand did his round-the-world balloon flight,

our children were very small.

At this age, children, they don't have any fear.

They are just living the present moment,

and I just realized I should not give them this fear.

The flight is long for him, huh?

This was one of his main question:

If I don't sleep, how can I survive?

First sunrise over a sea of clouds.

That's the sunrise I will remember all my life.

Switching on the solar generators.

I can show you my little house.

That's the kitchen where I prepare my food.

The toilet inside the seat.

That's the cellar.

Breakfast.

The family: Estelle, Oriane and Solange, Michèle.

Hello.

Hello, Solar Impulse, hello, Captain Piccard.

Good afternoon, Mr. Secretary-General.

I speak to you from the cockpit of Solar Impulse

in the middle of the Pacific,

flying on solar power.

All this airplane is like

a smart grid, collecting energy, distributing energy,

with very, very high efficiency.

And this is exactly what the world needs.

Wonderful.

You look like an astronaut in the moon.

Thank you, Mr. Secretary-General,

and congratulations for what you are doing.

The world will remember it.

While you are making history,

we have also made history today.

More than 175 countries signed the climate change agreement.

Thank you for your leadership and inspiration.

All the best to you-- bon voyage.

I think I had more butterflies in the stomach

before that live transmission than when I took off

with Solar Impulse three days ago.

The sun's going to arrive in a few minutes

to carry me to San Francisco.

It's beautiful.

Moment extraordinaire.

14 last years of attempts, of setbacks, of problems,

it was worth going through all these moments

just to be here, now.

Il est où, Stéphane?

The thing that amazes me is the size,

and especially given the low weight.

This is the moment

where you start to see electric power taking off.

Sometimes, you know, there are people who will say,

"Why do you fly with a solar airplane

"like Solar Impulse?

"It's expensive, it's big, it's slow, only good weather

and only one person in it."

Silicon Valley, nobody ask.

Everybody knows, understands.

When Solar Impulse landed yesterday in Phoenix,

it was just in front of a cemetery of old airliners.

It's very sad.

A lot of these airplanes will never fly again.

You know, they get dismantled.

This one lost, you know, the left eye.

Crazy.

Of course, it's normal.

All this will be replaced by better technologies.

But still, in fact, I feel emotions when I'm here.

An airplane is not just a piece of metal.

It represents much more.

When people think fuel is forever,

they forget the Gold Rush 100 years ago,

and the ghost towns.

I'm not saying Solar Impulse

will replace an airplane like that very soon.

In ten years' time, we have airplanes

flying electric with batteries,

plugged in the grid before take-off,

and they will transport 50 people.

Today you make electricity with solar panels in Dubai

cheaper than with gas.

Ladies and gentlemen, you are now doing your last flight

on the combustion-engine airplane.

In the future, you will be flying electric.

At mission control, there is no time off.

The team has one focus: getting across the U.S.

as fast as possible so they can cross the Atlantic

during the peak energy days of summer.

They will have to navigate around the turbulent air

over the Rocky Mountains,

the unstable thermals of the Southwest,

and the Midwest's infamous Tornado Alley.

Well, we arrived in the tornado season.

Every two or three days there are thunderstorms,

and those thunderstorms, they can lead to tornadoes.

The local news

came on and said this was landing,

so I went outside and watched the skies

to try to see something weird. All night long.

I don't buy into the global warming deal,

just to be honest.

We've had oil and gas for all these years.

But if they can make stuff battery-powered,

then I'm all for that.

They can obviously make it go faster.

Because I think you can drive faster

from Phoenix to Tulsa than he flew,

but it's a start.

Just as the Wright brothers did before them,

this team hoping to show anything is possible

with the right resolve.

But in Dayton, Ohio, a problem with the mobile hangar

reminds them just how fragile their plane is.

Today, we had a failure in the electric system

of the mobile hangar.

It deflated.

Touched the airplane,

it can destroy the airplane, huh?

The mobile hangar was laying on the tail of the aircraft,

slowly going down onto the wing.

I just would like to hear if there is a visual defect.

We have no idea what, especially here,

I'm not so afraid, but from the wing.

Until we see there is a problem,

it's stupid to cancel the flight of tomorrow.

Don't even think about it.

I hope we can fly again.

I think that's where we are.

Even though there may be no signs of external damage,

the weight of the collapsed hangar

may have cracked the plane's internal structure.

What we try to avoid is that we get into a panic stage.

Bertrand is pushing, of course.

Don't push this.

Don't push, this is not the moment.

We try, we go step-by-step.

So for me, for me, it's a non-event.

It's not a non-event, yeah?

Be careful what you say.

We are in deep.

In really deep.

Maybe there is nothing on the airplane, but we don't know.

This is an airplane which is certified

to fly over the major cities,

and you don't play with safety.

That's the responsibility of the engineers.

And I don't think we'll come with an answer

which is black and white.

To be sure the plane has no structural damage,

they must calculate the suspected load

on the tail and wing.

This project is too big

to be run just by personal wishes,

but this is very new for me.

After crunching the numbers through the night,

the engineers finally decide that the plane is safe to fly.

We had a couple of explosions,

very often because of our character,

maybe because of our egos.

And it was a hard process.

I think we understand that we bring to each other

much more than the difficulty that the relationship creates.

I don't think we're ever going to laugh

at the difficult moments we went through.

With André, we are together since 13 years in this project.

We're very proud that we didn't split apart,

that we didn't have any divorce.

That we could learn so much from each other.

As they arrive in New York, Bertrand is reminded

of the triumphs and struggles of his father, Jacques Piccard.

In 1969,

my father arrived with his submarine.

After the drift mission of one month in the Gulf Stream,

he arrived in front of the Statue of Liberty.

I was 11 years old,

so happy and proud.

You know, altogether, he had 50 projects of submarines,

and only five got some fundings.

I saw my father worn out by all these disappointments.

He told me, "Don't feel obliged to continue my work."

Now the Atlantic Ocean looms large.

Bertrand faces perhaps the biggest challenge of his career.

It's smaller than the Pacific,

but with notoriously harsher weather.

There's a cold front in their way--

a wall of clouds and unstable air

that's risky for the airplane.

After days searching, mission control in Monaco

notices a narrow corridor of clear skies starting to form,

leading to Sevilla, Spain.

The corridor that we've been following,

and that's really, it's really small.

Between all the bad weather to the north, to the south.

But they only have so much time before it closes.

Let's go for the Atlantic, my friends.

The Atlantic is going to be

probably the greatest flight of my life.

I don't want to put the pressure and say,

"Oh, I met Charles Lindbergh when I was a child,"

and imagine how important it is and how symbolic it is.

I want it to be natural.

I want it to happen in a peaceful way.

When you are in the middle of the unknown,

you have these moments of grace.

You are, at that moment, like you would like to be forever.

So now you are challenging your fighter pilots.

I love my fighter pilots.

Did I show you my map already?

Maybe André will not like this map as much as me

because the Pacific is very small on this map,

but the Atlantic is very big.

In front of you, the window is still open.

Behind you, the window has closed.

Bertrand makes it through the corridor just in time.

Next, he must harness the powerful winds of the Jet Stream

to propel him towards the coast of Spain.

Jet Stream is the conflict

between cold air in the upper levels

and warm air,

and they are pushing against each other.

At 20,000 feet, we may have 50 to 60 knots

pushing the aircraft

to the east to Europe.

And now we will fly very fast, huh?

An airplane powered solely by the sun

has made aviation history after an almost three-day flight

across the Atlantic from New York.

From Seville, the aircraft will continue its journey

back to Abu Dhabi, where it all began

for this extraordinary project.

When I flew yesterday over the pyramid,

they were just emerging out of the haze.

I guess it was exactly the same as they were 4,500 years ago.

They believed in eternal life,

and for me, it's a symbol of eternity.

Solar Impulse is also intended to be a symbol:

a symbol about sustainability,

a symbol about the potential of renewable energy.

If you build something like this,

which is done to be forever,

it's not necessarily the solution which we would go for.

Sustainability means that you stay in line with nature.

And I'm not sure in fact the way we build

takes this into account.

If you don't change the situation,

the world will dictate you the future

and not the other way around.

There are so many mixed thoughts and feelings right now

that it's difficult.

After this flight, it's over,

so it's like a family that's going to split.

But there is the message,

and what we have to do out of this flight,

and I'm working since years for that, and for that moment,

and I want to be sure not to waste it.

After 16 months and nearly 25,000 miles,

the last leg to Abu Dhabi

presents an unexpected final challenge.

They knew it would be hot in this desert region,

but now an extreme heat wave is posing a dangerous threat.

We never flew

with such a light aircraft in such conditions.

Extreme conditions.

Above the Saudi Arabian peninsula,

night temperatures at 3,000 feet hover around 90 degrees.

Mission engineers worry that critical systems on board,

which are not certified for such heat,

could completely shut down.

But their bigger concern is energy.

As the hot air cools during the night,

it creates strong downdrafts of wind

that push the plane to lower altitudes.

I didn't expect such an issue at the end, with the last leg.

The downdrafts are so strong

that he cannot fly through the night.

He will use so much energy to stay at this level

that he cannot survive during the night.

Take-off conditions on Sunday

are not good,

and we will have extreme thermals overhead.

I believe that each of the problems can be solved.

There is a danger that you overheat equipment,

and at the end, you have a failed aircraft.

After several days waiting,

the severe downdrafts appear to be subsiding.

It looks like the flight is back on.

As we are quite tight on energy,

timing is critical.

Every day there are cumulus clouds

that are really, really high.

Is the, is the pilot healthy?

This time the pilot is a little bit green, I have to say.

You mean it's stomach problems, or...?

Yeah, yes.

I'm a little bit weak,

but the general...

General situation is good.

Okay, then drink a lot of water, but you're the doctor, not me.

Keep in mind that the flight is not easy.

Yeah.

No, it's a difficult flight.

I know.

Absolutely.

Everything is different from what we have planned.

It's adventure.

It's not a business plan.

Nicolas Lugeon.

Claude, Staub, Jerome, Paige, Eoin.

Bertrand, are you okay?

It's not the moment I'm the healthiest in my life,

but it's still under control.

Still under control.

I hope it's the last taxi.

Because if it is, then it's fantastic moment right now.

I've never been in a project

that gave as many moments of elation

and moments of disappointment.

It's really strange.

It's really difficult.

As we told you, the night might be quite tough for you.

I would like to drink, I would like to pee,

I would like to hopefully re-evaluate my clothing

because I'm too hot,

but I just can't do anything else.

During the night, Bertrand must try to ride the updrafts

and avoid the downdrafts that will sap his energy reserves.

Once you have an updraft, just go with it,

and don't fight the downdraft with power.

Just let it go.

It was not such a bad idea that you had 17 years ago, huh?

You know what, it became a good idea

thanks to all the people who supported it.

We can't save the planet with one plane

flying around the world, but maybe it inspires

many people to start solving problems instead.

Then maybe it was worth all this stress.

We are late.

We really have to move, gentlemen.

How you will enter?

I don't have a...

You don't have a permit to enter.

I will go, I'm the pilot.

I tell you I will go.

You can shoot me, I will go and I will take my team.

When André took off the ninth of March last year,

I was thinking, "We are completely crazy."

And a year and a half later, you see the result

of what our team has achieved

because they accepted to dream.

And when you see the state of the world today,

it is a crime not to try something.

Not to try to increase quality of life

on this planet.

We love to fly.

For others, it's an art, in science,

in the community, but we have to try.

What I remember is to be on this runway 15 months ago

exactly at this position,

ready for the flight around the world.

Not knowing what will happen,

not knowing how much time it would take, just go.

Just go and start.

And seeing the airplane coming,

it's like slowing down the time.

It's really, really strong.

Whoa, God, we did it!

Wonderful!