All language subtitles for Fatal.Engineering.S01E01.1080p.WEB.h264-FREQUENCY_track3_[eng]

[narrator] With over 100,000
flights departing each day

from airports around the world,

the aviation industry
has cemented itself

into our daily lives.

[Rob] Aviation is often quoted
as the safest form of transport,

but whenever there is
an accident, sadly,

they're often examples
of fatal engineering.

Japan, 1985.

520 people died when Japan
Airlines Flight 123 encountered

a terrifying and unprecedented
technical problem.

It's a single blow that causes
a chain reaction of disaster.

Four years later,
England, 1989.

An engine failure
and insufficient pilot training

resulted in the death
of 47 passengers.

If you're gonna shut down
an engine, you need to make

sure that you're shutting
down the right one.

In the summer
of 1996, off the coast

of New York, TWA Flight 800
explodes 12 minutes

after takeoff due to
a terrifying and unprecedented

chemical phenomenon aboard
a commercial airliner.

All it would take was a spark
to turn the central wing tank

into a bomb.

Were these accidents the result
of unavoidable circumstances?

Or were they examples
of fatal engineering?

[electronic theme music playing]

Wednesday, July 17, 1996.
It's 8:19 pm.

[suspenseful music playing]

TWA's flight 800 takes off
from New York, bound for Paris,

with 230 passengers
and crew on board.

-[suspenseful music playing]
-[engine roaring]

[pilot over radio]
TWA's lifeguard 800 heavy,

eight thousand, two hundred
climbing on one thousand.

This aircraft has been
in service for 25 years,

logging over 93,000
flight hours.

[Rob]
You could call it a real veteran
with an impressive track record,

but on this particular day,
none of those passengers

will reach
their final destination.

[suspenseful music intensifies]

Just 12 minutes later,
disaster would strike.

As air traffic control attempts
to reach out to flight 800,

they receive only silence.

As the TWA Boeing climbs
to its cruising altitude,

people on
the ground and an airline pilot

aboard a nearby aircraft

see the plane explode in
midair over the Atlantic Ocean,

some 15 kilometers
from Long Island.

[explosion blasting]

[Tower] Eastwind 507,
you reported an explosion.

Is that correct, sir?

[pilot] Yes, sir,
about five miles out.

[Tower] TWA 800 -- [indistinct].

-[pilot] I think that was him.
-[Tower] I think so.

What happened?

What caused the deaths
of the 230 people on board?

[Shini] Though many on the
ground have suspected terrorism,

claiming to have seen missiles
directed up towards Flight 800.

The reality is perhaps
far more terrifying.

Right now, the Coast Guard,
the National Transportation

Safety Board, the FAA,
and the FBI are on the scene

of the crash.

Using massive search equipment,
they located the wreck

at a depth of 37 meters.

In the wreckage,
they retrieved the cockpit

voice and flight data
recorders.

[indistinct speaking
over radio]

These two orange boxes are
the final moments of TWA 800.

They offer to the investigators
a valuable first clue

and point them
in a surprising direction.

[Michel speaking French]

It's a strange occurrence
that might provide a key clue.

The malfunctioning fuel quality
indicators might be

the smoking gun.

Additionally, the cockpit
recorder reveals two unusual

aircraft sounds, sounds
that pilots and mechanics

can't interpret.

It's 8:31 p.m., the time when
the flight recordings stop,

the moment the plane explodes.

Eventually, the experts manage
to bring to the surface almost

500,000 pieces of wreckage,

95% of the aircraft,

and reconstructed it
in this Long Island hangar.

It is here that they will come
to understand the drama

that has played out
in this aircraft.

[speaking French]

And what they discovered
was that the explosion

that occurred could not have
come from an external object.

This explosion started
on the inside and blew out.

[Shini] The fuselage of the
aircraft had been bent outwards

around the wing center section
of the aircraft.

The center section
of the aircraft is the area

between the wings.

This is one of
the strongest sections,

with the fuselage connected
to the wings through structural

elements like spanwise
beams and spars.

This section also houses
a critical component involved

in the accident.

In a large aircraft,
like the Boeing 747,

you need a huge amount of fuel
to fly the massive distances

that they do.

And the majority of that fuel
is stored within the wings

and within what's called
a central fuel tank, which sits

in between the wings
within the fuselage itself.

This is the largest of all
fuel tanks on the 747.

The central wing tank can carry
almost 50,000 liters of fuel.

But on this particular day,
it's almost empty.

[speaking in French]

That central fuel tank didn't
need to be full.

There was enough fuel in other
fuel tanks around the aircraft.

The central fuel tank on this
flight only had about 2%

of its maximum capacity.

It contains only 300 gallons
kerosene.

Kerosene is partly chosen due
to the fact that as a fuel,

if you took a match to it
and tried to light it as

a liquid, it's just
gonna put the match out.

It's not that volatile
as a liquid, but as a vapor,

it becomes much more volatile.

All that was needed to create
it was a heat source and time.

And that heat is not far away.

Beneath the central wing tank
lie elements responsible

for the drama to come.

[speaking in French]

In summer, temperatures
in New York can exceed

30 degrees Celsius.

On July 17, 1996, TWA Flight
800 was originally scheduled

to take off at 7 p.m.

However, it was
delayed at the gate,

with its passengers already
on board.

A fleet service vehicle,
which helps to load and unload

aircraft between flights,
has broken down,

blocking the aircraft
at the gate.

Meaning that it wouldn't be
able to pull back

to go out to the runways
and take off.

Secondly, there was some
confusion around

passengers' luggage.

As a result,
the plane remains grounded.

But throughout the wait
for takeoff, the cabin remains

air conditioned for the comfort
of the passengers.

[Shini] What seems like a fairly
routine, though frustrating,

inconvenience has created
a deadly situation

in the plane's center wing tank.

Soon, it will develop
into a fatal disaster.

July 17, 1996.

TWA Flight 800 was
originally scheduled

to take off at 7 p.m.

However, it was
delayed at the gate,

with its passengers already
on board.

Nobody knows it, but two
of the three air conditioning

motors are heating up
the 1,000 liters of kerosene

in the center wing tank.

This action creates
an unprecedented situation,

terribly dangerous
for the entire aircraft

and its passengers.

That central fuel tank,
with a small amount of fuel

in it, is getting warmer
and warmer and warmer.

Though the aircraft's center
wing fuel tank was only loaded

with 300 gallons of fuel
for the flight to Paris,

there was another substance
slowly building up inside it

that would prove fatal.

This substance is known as fuel
vapor, and in a kerosene tank,

it's an extremely
dangerous gas.

[Michel speaking French]

[Shini] All it would take
was a spark

to turn the central wing tank
into a bomb.

8:02 p.m.

TWA 800 is finally cleared
to leave its gate.

It receives its departure
clearance and joins the queue

of aircraft awaiting takeoff.

Between its arrival
and departure, the aircraft has

been on the ground
for two hours and 45 minutes,

with two of its three air
conditioning motors operating

at maximum capacity.

8:19 p.m., the pilot sets
the engines to full power

to take off from
the end of the runway.

[tower] TWA 800...
Climb and maintain one-three
thousand.

[captain] TWA's 800 heavy climb
and maintain one-three
thousand..

This is when a spark
is introduced.

The flight recordings show
that 10 minutes after takeoff,

at precisely 8:29 p.m.,
the captain of TWA 800

commented on the abnormal
movements of the fuel gauges.

He is then cut off when air
traffic control asked him

him to climb to 15,000 feet.

Unfortunately, he never reaches
this altitude.

The jittery gauges in front
of the captain reflect what's

going on in the central tank.

The hot, dense fuel vapor
disturbs the seven

probes inside.

[Michel speaking French]

These electric components
operate safely within close

proximity to volatile
substances like jet fuel.

Even if there was a spark,
it wouldn't have enough energy

to ignite a combustion of fuel.

But that wiring was also
bundled with other cabling

and other wiring systems
within the aircraft.

And those wires had larger
currents running through them.

This grouping of cables provide
the final element to complete

this explosive cocktail.

What's believed to have
happened was that those little

crackles that were heard by
the captain and the flight crew

up in the cockpit...

with a short circuit and
some of those cabling systems

that required a larger current,
there's your spark,

the third element needed
for combustion.

Fuel,

oxygen, spark.

The rest is inevitable.

The time is 8:31 p.m.

As the plane reaches
an altitude of 13,800 feet,

the fatal cocktail explodes.

A massive explosion takes place
within the central wing tank...

blowing out that central part
of the aircraft, a key part

for its structural integrity.

The plane starts to buckle,
and the front of the aircraft

tears itself away from the back.

The cockpit, with a few rows
of seats behind,

plummets down into the ocean.

[Shini]
The rest of the plane continued
in the air, the wings still

connected to what remained
of the aircraft's fuselage.

[speaking French]

It took four years
and $35 million to complete one

of the largest air
investigations in history.

Following the accident,

modifications were made to
the aircraft's internal wiring

to prevent such a scenario
from happening again.

[Rob] Firstly, the wiring was
reconfigured so that no longer

would you have those
low current wires bundled

with higher current.

The chance of a spark
and an energy being transferred

into the fuel tanks
was eliminated.

Secondly, regulations were
introduced to make sure

that never again would you be
allowed to take off

with a small amount of fuel that
could easily turn into a vapor.

And finally, increased
insulation was installed

between the air conditioning
units and the central
fuel tank.

The flight of TWA 800
turned into one

of the world's greatest
air disasters.

But what happens when
you combine new aircraft

engineering design with old
ways of thinking, human error

can often also be the cause
of fatal engineering.

On January the 8th, 1989,
British Midlands flight 92

takes off from London Heathrow
on its way to Belfast

in Northern Ireland,

a flight it would have done
many times before.

[Shini]
This flight would be flown
by a brand new aircraft and had

been delivered to British
Midlands Airways one month

prior to that date,
Boeing's brand-new 737-400.

Major changes from previous
versions of the 737

include its modern dashboard
with the introduction

of digital functions
and its revolutionary

new CFM56 engines.

When the 126 passengers
and crew board Flight 92,

they have no doubt about the
reliability of this aircraft.

However, they will never
reach their destination.

27 minutes after takeoff,
this masterpiece

of aeronautical engineering
loses the use

of one of its engines.

Diverted for an emergency
landing, it crashed 900 meters

from the runway
at East Midlands Airport,

South of Nottingham,
in the small town of Kegworth.

[sirens wailing]

Despite the violence
of the impact that kills

47 people, 74 passengers
and crew miraculously survived

this terrible crash.

I was suspended upside down,
just with my safety belt

holding me on and my wife
just down below me.

The captain is
among the survivors.

Injured in his back and legs,
he is hailed for his courage

and decision making.

[speaking French]

To understand this,
we need to go back 30 minutes

before the crash.

8:52 p.m.

British Midland Flight 92
departs from Heathrow Airport

in London.

13 minutes after takeoff,
precisely at 9:05 p.m.,

as the plane nears its cruising
altitude, a worrying phenomenon

occurs on board.

[Rob] The pilots and a number
of the passengers realize

that something's not
quite right.

There's some vibrations
that feel more than what you'd

normally expect, and you can
feel it in the aircraft.

What they don't know is
that there's a problem in one

of the two engines.

The CFM56 is made up of two
inseparable elements that will

be the key components
in this deadly accident.

[speaking French]

The essential component
for making an aircraft fly

is the fan.

It is made up of 38 blades,
each 1.5 meters long.

These blades turn and they draw
in a huge amount of air

and thrust it out the back
that propels the engine forward.

But as the investigation will
reveal, one of the blades will

be the source of the problem.

Blade number 17 has suffered
a crack and it's shifted

its position slightly
within the configuration.

Not only does Blade 17 crack,

but as the engine continues
to rotate, it begins to twist.

As a result, the gap between
this blade and the one adjacent

to it widens, allowing more air
to pass at that point

through the engine.

As the fan continues to rotate
at a speed of 20,000

revolutions per minute,
this excess airflow

destabilizes the fan
and threatens the proper

functioning of the engine.

[speaking French]

That blade, having shifted
just a few millimeters, is now

touching the outer casing
of the cowling

that contains the engine.

As passengers look through
the windows, they see sparks

coming from the left engine.

Then they experience a second
terrifying event,

smoke in the cabin.

[speaking French]

At this point,
everyone understands

that the situation is abnormal,
and there is

a problem with the aircraft.

The passengers begin to panic.

The captain and his copilot
are highly experienced.

They have over 16,000
flight hours between them,

including 1,000 hours
on the Boeing 737.

Critically, however,
only 76 of those hours

are on this new model
of the 737.

Only one day of training was
required by the manufacturer

to obtain their certification
to fly the Boeing 737-400.

This included all the new
features of the aircraft,

as well as the nuances
of the aircraft

in emergency situations.

Relatively new to the Boeing
737-400, they're about to make

several fatal assumptions
and miscalculations.

The two pilots understand that
there is an issue with

one of the engines and begin
to assess the situation.

They decide to shut down
the engine that's causing

these vibrations.

Now, that in itself
isn't a big deal.

It happens fairly regularly.

When something's wrong
with an engine,

you can shut
it down.

The aircraft, like the Boeing
737-400, can fly safely

on one engine.

But if you're gonna shut
down an engine, you need

to make sure that you're
shutting down the right one.

British Midland Flight 92

departs from
Heathrow Airport in London.

The pilots can clearly see
on their instruments

that something is wrong.

However, they are not used to
the brand-new digital screens

on the dashboard.

The pilots can clearly see

that something's wrong
with the left-hand engine.

Their instrumentation
is showing it.

They can also
feel the vibrations.

However, as strange as it may
seem, the pilots will make

a mistake that will
prove fatal.

[engine whirring]

[speaking French]

The left-hand engine
that's causing

vibrations is now
the only thing providing

thrust, keeping the plane
in the sky.

The flight continues flying
on a single failing engine.

However, they do not yet
realize their mistake.

When they shut down the working
engine, the cockpit gauges

return to normal.

The vibrations
and the smoke stop.

[speaking French]

[Rob] And so it feels to the
cockpit that everything is fine.

The right decision has been
made, and we're going to land

in East Midlands Airport off
of the power from one engine.

At this point, they still have
time to realize their mistake

and restart the engine,
but they take no

further action.

The passengers can clearly see
that smoke,

and flames and sparks are still
coming out from this engine.

As flight 92 aligns
with the runway, the throttle is

pushed forward,
increasing the power demanded

from the left engine.

That is the turning point.

[speaking French]

It is 9:18 p.m.

The flames and vibrations
reappear.

During the investigation,
part of the outer casing

of blade 17, as well as
fragments from blades 4 and 5,

were found during flight 92's
final approach

to East Midlands Airport.

Blade 17, which had already
suffered fatigue damage

and came loose within
the engine's fan, had possibly

been ingested by the engine,
released from a trapped

position, damaging other
fan blades as it's drawn

through the engine.

[speaking French]

It becomes clear they will not
make it to the runway.

They're forced to make
the decision that no pilot ever

wants to make.
Forced to make a crash landing.

Between the plane and the
runway is one of the busiest

motorways in the UK,
the M1, and the plane's heading

straight for it.

The pilots don't have
many options.

In fact, they only have
two choices.

[speaking French]

The pilot chooses to crash onto
the slope near the highway.

30 minutes after taking off
from London, the captain makes

the most dreaded announcement
a commercial pilot can make.

Captain Hunt uses the intercom
to ask passengers to prepare

for a crash landing.

Some passengers manage
to get themselves

into the brace position.
Others do not.

Violent vibrations inside
the cabin cause the overhead

compartments to open,
and luggage falls

onto the terrified passengers.

The plane loses thrust
and begins to dive.

The plane makes contact
with the ground on one side

of the motorway, crashing
through fields and some trees,

crosses the motorway.

[Shini] The forward section
splits and continues onwards

up the embankment, while
the tail of the plane separates

and folds up on top
of the midsection

and the passengers in the main
cabin section of the aircraft.

British Midland Flight 92
crashes just 900 meters

from the runway
of East Midlands Airport.

Miraculously, no one
on the highway is injured.

You might argue that this was
a case of fatal engineering

because of the errors
that occurred in that left-hand

side engine, the cracks,
the movement

of the turbine blades
that caused the fire

and the vibrations.

But in this case, the pilot made
the wrong decision.

[speaking French]

Because of this fatal error,
47 people died, and 74

will carry the lasting effects
of their severe injuries.

This avoidable tragedy caused
a shockwave throughout

the aviation industry.

Due to Captain Hunt
and First Officer McClelland's

relative inexperience
in the Boeing 737-400

under such dire
circumstances and Boeing's

inadequate pilot training,
recommendations were made

to ensure all pilots
are thoroughly prepared

before taking control
of a new aircraft variation.

[Rob] Undoubtedly, the catalyst
for the British Midlands

aircraft disaster was a fault
within the engine.

But what happens when
your engines are working fine,

but you lose the ability
to control the plane in the air?

We're in Japan
at Tokyo's Haneda Airport

on August 12, 1985.

Japan Airlines flight 123
departs for Osaka.

It's 6:12 p.m.

This is a 54 minute flight,
so a relatively short flight.

But in Japan, the number
of people wanting to make

this flight is huge.

And so Japan Airlines regularly
use a Boeing 747, crammed full

with 500 passengers,
shifting people

between Tokyo and Osaka.

Specifically designed
for the Japanese market,

this Boeing 747-SR46

is the largest airliner
of its time, it can accommodate

up to 550 passengers.

With 524 passengers and crew
members aboard, it is nearly

full when it takes
off from Tokyo Airport.

[Rob] Twelve minutes
into this particular flight,

something goes devastatingly
wrong with the aircraft,

and it never makes
its destination in Osaka.

An explosion occurs
at the rear of the plane,

depressurizing the cabin,
and destroying both the tail's

rudder and hydraulic systems,
making the aircraft

uncontrollable, a nightmare
for every passenger.

For over 30 minutes,
the pilots fight

with the aircraft,
repeatedly informing ground

crews that they have
lost control.

-[pilot yelling over radio]
-[engine roaring]

[alarms beeping]

At 6:56 p.m., 44 minutes after
its takeoff, the plane crashes

into the slopes
of Mount Osutaka,

100 kilometers from Tokyo.

[suspenseful music playing]

The crash results
in 520 deaths.

Never has an aviation disaster
involving a single aircraft

claimed so many victims.

Incredibly, rescue teams
managed to find four survivors

within the wreckage
of the plane.

[Shini] But was such a tragic
loss of life avoidable?

Were warning signs missed?

Was flight 123 a case
of fatal engineering?

[Rob] In order to understand
what's happened here,

we need to go back in time
seven years back.

When, on one occasion,
when this plane was taking off,

it suffered a tail strike.

In aviation, a tail strike
refers to the moment when

the tail of the aircraft
touches the ground

during takeoff or landing.

This is what happened
on June 2nd, 1978,

at Osaka Airport.

[speaking French]

As an airplane climbs higher,
it enters a zone where the air

is thinner, colder, and
unsuitable for the human body.

To maintain a comfortable
atmosphere for the people

on board, the cabin is kept
at normal pressure.

It is pressurized with air
taken from the aircraft's

engines and pumped
into the cabin.

This disc-shaped bulkhead
is the essential shield

that separates the pressurized
rear cabin from the tail

of the aircraft,
which is not pressurized.

[Shini] Without this bulkhead,
pressure would be lost through

the back of the aircraft
and would be unable to maintain

a suitable atmosphere
at a plane's cruising altitude.

This is why all repairs
must be done meticulously,

but in this case, it was not.

Once the repair was finished,
inspectors discovered

an alarming situation.

There were significant gaps
between parts of the new

bulkhead that threatened
its proper functioning.

To solve this major issue,
engineers decided to install

a junction to serve as a seal
between the two parts involved.

However, the junction plate was
difficult to install due

to the curvature of both
the plate and the bulkhead.

Boeing engineers decided to cut
the plate to install it

and used half as many rivets as
needed, a choice that would be

fatal for Japan Airlines
Flight 123.

[speaking French]

And over a period of time,
those repairs started

to suffer cracks and started
to become unstable.

On this flight, that instability
became disastrous.

It was a ticking time bomb.

August 12, 1985.

The Japan Airlines Boeing 747
has been in flight

for 12 minutes
and is approaching

its cruising altitude
of 24,000 feet.

[Shini] As passengers and crew
settled into the flight,

a loud boom thunders
through the plane.

Over time, cracks in the
weakened area of the bulkhead

created an air gap
that disrupted the balance

of the cabin's pressurization.

The bulkhead could not
withstand this influx of air.

Inevitably, it explodes.

Suddenly, the cabin is
no longer pressurized.

It is exposed to the atmosphere
and the air pressure

at the altitude where the plane
found itself, which is much

lower than what we find
when we're on earth.

As such, there's not
as much oxygen.

The oxygen masks drop
from the overhead compartments.

The captain realizes the cabin
is undergoing rapid

depressurization and that the
passengers' lives are at risk.

[captain speaking Japanese
over radio]

He descends to a lower altitude
so the air becomes breathable

for those on board and requests
an emergency landing

at Tokyo Airport.

[captain speaking Japanese
on radio]

[tower speaking Japaense]

[Rob] The crew knows something
has happened, but they can't see

the entirety of the plane.

They don't know exactly
the extent of the damage that's

been caused by this loud bang,
this explosion somewhere

in the aft of the plane.

[speaking French]

This photo was taken during
that hellish flight

by a witness on the ground.

It illustrates the horrifying
tragedy of Japan Airlines

Flight 123, carrying
524 passengers and crew.

Unbelievably, the tail is
missing from this aircraft.

The tail will be found
in Sagami Bay, 60 kilometers

from Tokyo Airport.

When the partition exploded,
the air pressure inside

the cabin rushed toward
the tail of the plane.

This extremely violent
decompression is the trigger

for the worst case scenario.

[speaking French]

[Rob]
Without those two controls,
as the pilot, you have very

little input to dictate
the movement of the aircraft.

6:28 p.m.

Four minutes after the
partition rupture and the loss

of cabin pressure,
the captain informs air traffic

control that the plane
is uncontrollable.

They are given permission
to land at nearby airports.

[tower speaking Japanese
on radio]

[captain responding in Japanese]

However, the aircraft begins
to perform maneuvers

that are, at once,
dangerous and terrifying.

The phenomenon is known
as phugoid motion.

It occurs when the aircraft
repeatedly gains and loses

altitude in several phases.

The plane comes down through
gravity, builds up speed,

the lift in the wings
increases, and the plane

goes up again.

As it goes up, it loses
its speed, and so gravity

dictates that it comes down,
almost like it's

on a roller coaster.

6:48 p.m.

JAL flight 123 is now only
7,000 feet above the mountain

ranges of the Japanese Alps.

The mountains are getting
closer, and the crew

desperately tries to find a way
to control the plane,

as the flight controls are
no longer responding.

When the bulkhead ruptured
and the pressure exploded

in the tail of the aircraft,
it wasn't just the vertical

stabilizer and rudder
that were destroyed.

The tail also contains
components of another critical

system onboard the aircraft,
the hydraulic system.

[Shini] The Boeing 747,
like most planes, uses a series

of hydraulics to power flaps
on both the tail and the wings

of the plane.

By tilting these flaps
with ailerons, the pilot can

then control airflow
around the plane,

and therefore the plane's
direction and speed.

However, when the explosion
of the pressurization bulkhead

tore off part of the tail,
it also damaged hydraulic

system pipes located there.

The fluid they contained,
vital for the system

to function, gradually
began to leak out.

Within 60 to 90 seconds
following the explosion

at the rear of the aircraft,
hydraulic pressure was

completely lost.

6:50 p.m.

The crew of JAL flight 123 has
lost control of the aircraft

for 26 minutes.

[speaking French]

[Rob] No matter how hard
he tries,

his efforts
will be unsuccessful.

For 30 minutes,
the pilots fight courageously

to keep this 260-ton aircraft
in the air, a 30-minute

nightmare for everyone on
board, during which passengers

record their final moments.

[speaking French]

6:55 p.m.

43 minutes after takeoff,
the airports of Haneda

and Yokota confirm
they are ready to receive

flight 123
for an emergency landing.

[captain speaking Japanese
over radio]

The crew on board
confirms the message,

but it's their last
transmission.

Despite the heroic efforts
of the pilot, inevitably

the plane crashes.

-[pilot yelling]
-[engine roaring]

-[alarm beeping]
-[yelling continues]

And it crashes
into a mountain ridge.

[Shini] The plane continued
forward with the passengers

in this section experiencing
forces greater than 10 to 20 G.

[explosion rumbles]

According to onboard seismic
sensors, it is 6:56 p.m.

when the plane the plane makes
its final movements

on the ground,
and the debris settles

into its final position.

What we know is that there were
no survivors in the front

of the aircraft, but there were
dozens of survivors

in the rear.

Despite the power
of the impact, some passengers

have survived.

However, they are in
a remote area

in the Osutaka Mountain Range,

over 1,600 meters
above sea level in the middle

of the night.

They have to wait 12 hours
before rescue teams reach

the crash site,
12 hours that will be fatal

for the majority
of the survivors.

Only four would survive
until the following morning.

In addition to the four
survivors, the rescue teams

find a camera.

On it were photos
from the final moments

inside Flight 123.

[speaking French]

Aviation is often quoted as
the safest form of transport,

and the statistics
play that out.

But whenever there is
an accident, sadly,

they're often examples
of fatal engineering.

After the accident, Boeing took
steps to modify the hydraulic

systems of its planes in order
to prevent such a tragic

scenario from happening again.

This disaster also served as
a true lesson on the importance

of aircraft maintenance,
a lesson for the entire

aviation industry.