All language subtitles for Air.Disasters.S05E10.Terror.In.Paradise.1080p.PMTP.WEB-DL.AAC2.0.H.264-maldini_track3_[eng]

Man: Cleared for takeoff
for Tahiti, runway 1-2.

Narrator: One of the most rugged
planes ever built...

Man: Pilots all called it
the Jeep In The Sky.

Narrator: ...crashes into
the sea near Tahiti.

Man: A plane doesn't just crash
for no reason.

Narrator:
Air traffic controllers

have no idea what happened.

Controller:
We're a small airport here.

We're not equipped with radar.

Man: It looked like
it was going to be

a very difficult investigation.

Narrator:
Was it a medical emergency?

Man: The pilot might have had
a physical breakdown.

Narrator: An act of sabotage?

Man: No!

Narrator: Or something
even more alarming--

a hidden threat that lurks
at commercial airports

around the world?

Flight attendant:
Ladies and gentlemen,
we are starting our approach.

Pilot: We lost both engines!

Flight attendant:
Put the mask over your nose.

Emergency descent.

Pilot: Mayday, mayday.

Flight attendant:
Brace for impact!

Controller: I think I lost one.

Man: Investigation starting...

Man: He's gonna crash!

Narrator:
Pilot Michel Santurenne

cruises low over the islands
of French Polynesia.

Michel Santurenne: Air Moorea
requesting clearance

for approach, runway 1-2.

Narrator: It's one of
up to 40 flights a day

between the islands of
Moorea and Tahiti.

Controller: Air Moorea,
you are cleared for final.

Runway 1-2.

Narrator: It's a route
Eric Limore knows well.

Eric Limore, translated:
Moorea is an island

that's really close to Tahiti.

The distance between them
isn't even 20 kilometers.

There's just the channel
to cross.

Narrator:
Tahiti and Moorea are two

of more than a hundred islands
that make up French Polynesia,

halfway between Australia
and South America.

Pristine beaches and
lush mountain peaks

attract thousands of
tourists a year.

Air Moorea specializes
in the short flights

that provide a vital link
between the islands.

Limore: Air Moorea and
its planes were really part

of the daily landscape
for the Polynesians--

people working in Tahiti
and living in Moorea--

and for the tourists.

It really was the quickest
and most efficient link.

Santurenne: Me again.

Narrator: Michel Santurenne
joined Air Moorea

just three months ago.

Santurenne: I'll take the
passenger list and load sheet

if it's ready.

Narrator: After a career
in the military,

he's beginning a new life
in paradise.

Limore: He had taken care
of everything

to welcome his family.

His wife was joining him soon.

Santurenne:
Ah, another full one.

Just the way we like it.

Narrator: Santurenne flies
these short hops on his own,

with no co-pilot or cabin crew
to help out.

Santurenne: Ok.

Time to fly.

No time to waste in paradise.

Narrator: Every 30 minutes
he needs to be ready

for another takeoff.

Limore: The captain would
quickly check the plane

to see if there was anything
alarming, a deflated tire,

anything that might
call their attention.

Narrator:
The twin otter turboprop

is a rugged 19-passenger
aircraft built in Canada.

Limore: In fact, we pilots all
called it the jeep in the sky.

Santurenne: Nice shirt.

Limore: We would greet the
passengers quickly and reboard.

It was very, very short,
let's say.

Man: How are you doing?

Santurenne: Just put the luggage
in the seat in front of you.

A beautiful day to fly.

Narrator: After less than
15 minutes on the ground,

Santurenne is ready to go again.

Santurenne: Tower,
we're ready to taxi.

Controller: Air Moorea, you are
cleared for takeoff, runway 1-2.

Santurenne: Cleared for takeoff
for Tahiti, runway 1-2.

Narrator: The twin otter
has little automation.

Santurenne flies
this plane by hand.

Limore: The majority of
modern commercial planes

are loaded with help
for the pilots--

electronics, screens--

but on this type of plane,

you have the pleasure
of handling the plane

and fully controlling it.

Narrator:
At this island airport,

the ocean is just off the edge
of the 1,300-yard runway.

Limore: When we fly over there,
it's magical--

blue lagoons,
magnificent islands,

the greenery,
the mix of colors--

it's certainly paradise.

Narrator:
Vacationers get to watch

the regular takeoffs
and landings.

The flight is one of
the shortest on earth--

just seven minutes from
takeoff to touchdown.

Santurenne: Huh?

Damn it!

Narrator: But on flight 1121,
something is wrong.

The twin otter
is losing altitude fast.

Woman: Oh, my god!

Narrator:
It falls into a steep dive.

Less than two minutes
after takeoff,

flight 1121 crashes
into the pacific.

Woman: Oh, my god!

Woman: Look!

Narrator: The tower is told
what people have seen.

Controller: Is it floating
or has it gone under?

Narrator: Local fishermen
rush to help.

But they find no survivors,
only bodies.

All 20 people on the flight
are dead.

Limore: I will always remember.

It was terrible, because
we were still hoping

that despite what happened,
people would come out alive,

or at least a couple.

Narrator: The disaster touches
nearly everyone

in the tiny island community.

Limore: In Polynesia
everyone knows each other.

Everyone is someone's cousin
or knows their family,

so people were hit very hard
by this accident.

Narrator: The Air Moorea fleet
is grounded

when pilots refuse to
fly the twin otter

until they know
what caused the crash.

Limore: A plane doesn't just
crash for no reason.

It was either due to pilot error
or a mechanical problem.

So before continuing to fly,

we asked that the whole fleet
be checked out.

Man: Bonjour.

Narrator: Because Moorea is
a French territory,

a team from France's accident
investigation bureau,

the B.E.A.,
is sent from Paris.

It's their job to figure out
what went wrong.

Alain Bouillard:
Tell me there's more.

Narrator: Alain Bouillard leads
the investigation.

Bouillard, translated:
The twin otter was
an extremely robust plane

that was used in
all the difficult places

where other planes can't
normally take off and land.

That made us wonder, what could
have happened to this plane

that would have made it
hit the water?

Narrator: Investigators usually
rely on clues from the wreckage.

Bouillard:
This tells us nothing.

Narrator: But most of this plane
is at the bottom of the ocean.

Bouillard will have
little to go on

unless he can get vital pieces
back on dry land.

Bouillard: We are going to need
a lot more wreckage than this.

Narrator: There's another reason
to find the plane.

Unlike large airliners,

twin otters are not required to
carry cockpit voice recorders.

But Air Moorea
installed one anyway.

It could hold the answers
investigators are looking for.

Arnaud Desjardin:
We were hoping to get,

in addition to the voice
in the cockpit voice recorder,

any kind of alarms
that would sound.

Narrator: But recovering the CVR
from the deep waters

off the coast of Moorea
will be a huge challenge.

Desjardin: Way too deep
to send down divers.

The sea depth at this area
was around 700 meters,

so obviously,
we cannot send any diver.

You need to send

a remote control-operated
submarine.

Narrator: Investigators arrange
for a ship

equipped with
a remote-controlled submersible

to assist in the recovery--
the ile de re.

There's just one catch--

it's more than 2,400 miles away
off the island of New Caledonia.

It could take weeks for the ship
to get to Moorea.

Flight 1121's CVR is equipped
with a locator beacon,

or pinger, but the battery
that powers it

will only last 30 days.

Desjardin: We tried to send
that recovery ship

as soon as possible

and within the 30 days of
the battery life of the pinger.

Bouillard: It looked like
it was going to be

a very difficult investigation

if we couldn't recover
the cockpit voice recorder.

Narrator: Meanwhile,
investigators talk

to the controller
at the airport.

A radar track could
provide some clues

about what brought
the plane down.

Desjardin: The first evidence
that we like to get

when the investigation starts,
of course,

is a sense of the trajectory,

the last departure point
and the impact point.

So we try to get
this type of information.

Narrator: But they're not going
to get what they hope for.

Controller:
We're a small airport here.

We're not equipped with radar.

Narrator:
It's yet another setback.

Desjardin: When we discovered

that we did not have
any radar data,

we were slightly disappointed

in the sense that we knew
it was going to be harder

to recreate the trajectory
of the aircraft.

Woman:
I saw the plane climbing,

and then suddenly
it dove into the water.

Narrator: Until the ile de re
arrives,

investigators must rely on
the only evidence they have--

witness reports of the crash.

Bouillard: We thought
it was critical

to gather all
the eyewitness accounts

to help us understand
what happened.

Desjardin: Most of the witnesses
were either on the beach

in Moorea,
or on the boats, fishing.

All of them stated that they saw
the aircraft climbing normally.

Narrator: Every day more than
500 twin otters navigate

some of the most challenging
routes on earth--

from the Australian outback

to the frozen tundra
of the far north.

If there's a fatal flaw in
the famously sturdy twin otter,

the aviation world needs to know
as soon as possible.

Investigators are under pressure

to figure out what brought down
flight 1121.

Bouillard:
He was climbing normally,

then seems to lose control
of the plane.

Maybe it was their weight?

Desjardin: When you have
a weight imbalance issue,

you usually have your troubles
right after takeoff.

Narrator:
Correctly calculating the weight
of cargo, passengers and fuel

is critical
on small commuter planes.

Getting it wrong can be deadly,

as a crash in the United States
demonstrated in 2003.

U.S. Airways Express flight 5481

departs from
Charlotte, North Carolina.

Just 30 seconds after takeoff

the pilots lose control
of their beechcraft 1900.

The commuter plane
plummets to the ground,

hitting an airport hangar and
killing all 21 people on board.

Investigators discover the plane
was dangerously overloaded--

more than 550 pounds over

its maximum allowable
takeoff weight.

The crew used
incorrect estimates

for passenger
and baggage weight.

Desjardin: It's very important
to know the weight

of your aircraft
before you take off.

And therefore, we did
investigate this issue

very, very soon
into the investigation.

Bouillard: 19 passengers
with fuel and cargo.

Narrator: The B.E.A. Team checks
the load and balance sheets

from the air Moorea flight
and finds no issues.

Desjardin: We found out that
everything was within

the manufacturer's limits.

Bouillard:
They should have been fine.

Narrator: Whatever brought down
the plane,

it had nothing to do
with weight.

Until help arrives to search

for the plane's sunken
cockpit voice recorder,

there is no more evidence
to go on.

Bouillard decides to take
a chance on an unusual tactic

to try to figure out
what went wrong.

Bouillard: I need a small plane
and a good pilot.

Merci.

Narrator:
Above the island of Moorea,

Alain Bouillard takes
an unusual flight

aboard a small commuter plane--

a flight he hopes
will enhance the memory

of those who witnessed
the crash of flight 1121.

Bouillard: Ok, let's make
a pass over the lagoon.

Narrator: Pilots have
a specific task to do

at each stage of the flight.

If witnesses can identify
how high santurenne climbed,

it might help investigators
figure out

what he was trying to do when
he lost control of the plane.

They ask witnesses to watch

as Bouillard's plane climbs
from the airport.

Desjardin: If you ask them
what was the maximum altitude,

they might not
be able to tell you,

oh, this was 500 feet or
1,000 feet or 2,000 feet.

But if you actually show them
an aircraft in the air,

and say, this is 500 feet.

Did it match what you saw?

They can say more easily,
yes or no.

Woman: No, it's too high.

Bouillard: Ok, let's make
one more pass,

this time a little lower.

Desjardin: We asked
the witnesses to tell them

which one of the recreated
flights matched the most

what they remember from
the day of the accident.

Woman: Yes, that's exactly
where I saw the plane.

Man: The right height.

Bouillard: Excellent.

We're at an altitude
of almost 400 feet.

Ok. Let's go back.

Narrator: The test flights
give Bouillard a good idea

of how high Michel santurenne
managed to climb.

Bouillard: The flights we did
allowed us to estimate

the altitude at which the plane
changed its trajectory.

Whatever went wrong, it happened
when he was still climbing.

Narrator: But he still
doesn't know

what caused the plane's
sudden dive,

or why the pilot
couldn't recover.

Desjardin: When you have
an airplane going nose-down

after takeoff, you can think of
engine failure, obviously.

Dual engine failure.

Narrator: A twin otter can fly
safely with only one engine.

But if both engines fail,
that could cause a steep dive

like the one the witnesses saw.

Desjardin: That was
a possibility.

It would match,
in terms of trajectory.

Narrator: But having two engines
fail at the exact same time

is an extremely rare event.

Desjardin: Dual engine failure
could be caused, of course,

by fuel starvation,

but that's quite unlikely
right after takeoff.

Or, it can be also, let's not
forget bird ingestions

in both engines, but that's
quite unlikely also.

Narrator: Most witnesses also
report hearing engines

as the plane dove
towards the sea.

Dual engine failure now seems
even more unlikely.

Sounds captured by
the cockpit recorder

could confirm if
the engines were running.

But until it's recovered,

Bouillard only has the unusual
flight path to go on.

Bouillard: This information was
certainly important,

but it didn't explain
what happened.

It seemed to us that the pilot
might have had

a physical breakdown,

some kind of incapacitation that
put the plane into a descent.

These are planes that are flown
by a single pilot.

When a pilot is physically
incapacitated,

there's no one to take over
control of the plane.

Desjardin: If the pilot
had been incapacitated,

and then would have just,
you know,

leaned over on
the flight controls,

indeed it would then match
the trajectory of the aircraft.

Narrator: The captain's body
has been recovered

and sent for autopsy.

The coroner checks for any signs
of a medical condition

that might interfere with
the captain's ability to fly.

But when Bouillard
reads the results...

Bouillard:
It wasn't a heart attack.

Narrator:
...he's back at square one.

Limore: There was nothing
to suggest

that he had a health problem.

We have regular
medical checkups.

He passed without
any difficulty.

Bouillard: We closed the door
on pilot incapacitation

as the cause of the accident.

Narrator: Bouillard must
consider every possible cause

for the crash.

He explores
a terrifying possibility.

Bouillard: What about
a deliberate act of sabotage?

Narrator: Did someone
board the flight

intending to commit murder?

Bouillard:
Intrusion into the cockpit,

it's something that
was plausible.

Narrator: Bouillard knows that
it's happened before.

December 7, 1987.

A disgruntled airline employee
smuggles a handgun

aboard Pacific Southwest
Airlines flight 1771.

In mid-flight he shoots
his former boss,

then rushes towards the cockpit,

where he shoots a flight
attendant and both pilots.

He then forces the plane
into a steep dive.

There's no hope for any
of the 43 people on board.

The small jet slams
into a california hillside

and disintegrates.

Santurenne: I'm sorry, sir,
you can't be...

What? What are you doing?

Narrator: If someone on
Air Moorea flight 1121

entered the cockpit
and attacked the pilot,

the sound of the struggle

would be on
the cockpit voice recorder.

Bouillard: At this stage
of the investigation,

it was pretty obvious
that we had to find the CVR.

Narrator: On August 26th,
17 days after the accident,

the French research vessel
ile de re finally arrives.

The team knows the approximate
location of the wreckage,

but ocean currents may have
shifted the sunken debris.

Desjardin: We had narrowed down
the search zone

to a circle of about
260 meters in diameter.

We were fairly confident
it was going to be in that zone,

but we didn't know
if it was gonna be

laying by itself on the seabed,

or if it was still in
the fuselage of the aircraft.

Narrator: They zero in on
the recorder's locator beacon.

Bouillard: That's the sound
we're looking for.

Narrator: Technicians on the
ile de re

launch a remotely operated
underwater vehicle, or rov,

towards the sound.

Bouillard: We quickly we located
the area on the sea floor

where the wreckage
was dispersed.

There's our twin otter.

Narrator: The remains of
Air Moorea flight 1121

lie more than 2,000 feet
below the waves.

Bouillard:
We saw the detached wings.

We saw the engines.

We saw part of the cockpit.

See if you can find the tail.

The decision was quickly made
to focus on the tail,

where the cockpit voice recorder
could be found.

Ok, let's cut it open and
get the CVR out of there.

We decided to cut through
the fuselage

to recover the flight recorder.

Narrator:
It's a delicate operation.

One false move, and the sub
could damage or destroy

the crucial recorder.

Bouillard: Nice and easy.

Desjardin: We were really hoping
to find it there undamaged,

or just slightly damaged,

and therefore increasing
our chance of success

for the readout process.

Narrator: The salvage operation
demands incredible patience.

Bouillard:
This job of cutting out,

or of the rov chewing open
a hole in the plane

took five or six hours of work

before we could get to
the cockpit voice recorder.

Narrator: Finally the team
frees the CVR.

Bouillard: We got it.

Excellent work.

We felt a great sigh of relief.

Desjardin: So it was a sense
of satisfaction,

and then also worries, because
if you have the recorder,

that's a very good thing,

but then you have to have
the data in it.

So the next phase to organize

was shipping the recorder
back to the lab at the B.E.A.

For a readout
as soon as possible.

Narrator: Along with
the voice recorder,

the salvage effort brings up
other key pieces of wreckage.

Bouillard: We decided to recover
some of the pieces

that we thought would be needed

in addition to the information
from the CVR.

Desjardin: We wanted to get
the engines.

We wanted to get as much
cockpit panel as possible.

Narrator: They quickly download
the CVR data.

A lone pilot hardly
speaks at all.

Investigators must listen
for other sounds

that could provide leads.

Desjardin:
On the cockpit voice recorder

we could hear
the normal takeoff roll,

and then the climb phase
seems to be rolling normally.

Narrator: They can hear
the sound of the plane

as santurenne lifts off
and adjusts his controls.

Bouillard: An intrusion
into the cockpit

was still an open hypothesis.

We waited for the CVR
to close that door.

Narrator: There's no sound of
an intruder in the cockpit.

Bouillard: The first impression
we got from listening to the CVR

was that there was no intrusion
into the cockpit,

there had been no other
people in the cockpit.

Narrator: Then they hear
the pilot cry out in surprise.

Santurenne: Damn it.

Bouillard: Everything was
perfectly normal,

until the moment
when the pilot swore.

Narrator: The sound recorded
in the cockpit

allows investigators to rule out
another theory as well.

Desjardin:
The engines sound fine.

The CVR proved they are at
their maximum takeoff power

all the way to impact.

It sounds like
he's pulling in the flaps.

Narrator:
The pilot's cry of surprise

comes just after he adjusts
the flaps on his twin otter.

Desjardin: Again, please.

You could hear on the CVR
the flap being retracted.

You can also hear the pilot
breathe a little bit heavier,

like he was pulling on the
flight controls at that time.

And then immediately after that,

we hear him being
very surprised.

Santurenne: Damn it.

Narrator: Moments later,
the plane slams into the sea.

Desjardin: Even with
a lot of experience,

cockpit voice recorders
always are hard to hear,

especially when you know there's
a tragic, tragic ending.

It's connected to the flaps.

Just, I don't understand how.

Narrator: Investigators learn
that on flights to Tahiti,

twin otter pilots
retract their flaps

when they reach about 400 feet--

the same altitude where
flight 1121 began to dive.

They wonder if the flaps
malfunctioned.

Before takeoff, pilots routinely
extend their wing flaps

to increase lift
while they climb.

Limore: Once the plane
approaches cruising altitude,

extended flaps increase drag.

So pilots must retract them when
they approach cruising altitude.

Narrator: Investigators study
the mechanism

that operates the flaps.

Desjardin: We did recover
the flap actuator,

and we were able to analyze it.

Narrator: They find that
it's in the correct position

and shows no sign
of any malfunction.

Bouillard: Flaps are fine.

Desjardin: The results of
the examination showed

that the flaps were retracted
at impact.

Narrator: After weeks of work,
Bouillard still can't explain

why flight 1121
fell out of the sky.

Bouillard: Now let's take
a good, close look

at these cables.

Narrator: He focuses on
the cables that operate

crucial control surfaces
in the tail of the plane.

Bouillard: We were left
with the possibility

of a mechanical breakdown
or failure.

Narrator: The control surfaces
in the tail of a twin otter

are activated
by just four cables.

Two move the plane's rudder
right and left,

and two move the elevator
up and down.

All four were damaged
in the crash.

Bouillard looks for anything
that might tell him

when and how they snapped.

Aviation cables are made up of
multiple strands of thin wire

that are twisted and
then braided together

for extra strength.

Three cables have unraveled--

clear indication that they were
ripped apart suddenly on impact.

Bouillard: Impact damage.

Narrator: But one cable
looks different.

Bouillard: Now, this,
this is interesting.

This one did not snap on impact.

Desjardin: One cable was broken
in a different manner

than the three other ones.

So that was something
that we had to investigate.

Narrator: Two cables run
to the elevator on the tail.

One pulls it down
to pitch the nose down.

The other cable pulls it up
to pitch the nose up.

That's the one that broke
before impact.

If it snapped in flight,

the plane would have been thrown
into a severe dive.

Santurenne: Damn it.

Bouillard: The failure of
the pitch-up cable

was consistent with
the trajectory

that was described
by the eyewitnesses.

Narrator: Finally investigators
understand why

Michel santurenne lost control
of his twin otter--

an extremely rare
mechanical failure

that came without warning.

It's a revelation that leads
to a more urgent question.

Bouillard: Ok, let's send these
to Estelle in Paris

and see what she thinks.

Narrator: They must now
figure out why the cable snapped

before it happens
to someone else.

When the pitch-up cable
arrives in Paris,

materials specialist
Estelle Bancharel

examines it closely.

She sees something strange.

The cable shows clear evidence
that different strands broke

at different times
and for different reasons.

Estelle Bancharel, translated:
The external strands were worn,

and those on the inside
were not.

They had snapped.

Narrator: Distinctive damage
on the outer strands

suggests something has been
rubbing against the cable.

Bancharel: It looks like
50% worn down over time.

When we looked at this cable
under the microscope,

we were able to see that
every external strand

showed these signs of wear,

which added up to
very substantial damage.

Narrator:
The pitch-up cable runs

from the control column
in the cockpit to the elevator,

passing through a series
of plastic guides.

Every time the pilot
pulls the nose up,

the cable rubs against
the guides.

Planes experience
the most wear and tear

during takeoff and landing.

It's important for mechanics to
monitor the number of flights

to help assess wear.

Bouillard: 48...

Narrator: Airline records
provide a troubling clue.

Bouillard: More than
50 flights here.

Controller: Air Moorea,
you are clear for final.

Narrator: Air Moorea planes
make frequent short hops

and make many more
takeoffs and landings

than most large airliners.

Limore: On average, it performed
50 to 70 takeoffs a day,

and landings, too--
the same plane.

Narrator: Investigators
need to know

how all that
back and forth movement

could have affected
the pitch-up cable.

They devise a test
that replicates

the friction on the cable.

But there's another factor that
must be taken into account.

Bouillard: This is the only
plane in the Air Moorea fleet

with stainless steel cables.

Desjardin: And we found out that
there was a different type

of control cable used
for this particular aircraft.

Narrator: The accident plane
is a new addition

to the Air Moorea fleet.

The airline's other planes
have control cables

made of carbon steel,

but flight 1121's cables
are made of stainless steel.

Stainless steel withstands
salt corrosion

better than carbon steel.

Desjardin: It would make sense
to make the decision

to use stainless steel, so that
your cables would corrode less

in a very saline environment.

Cables could be susceptible
to corrosion more

than if you would
operate over land.

Narrator: But stainless steel
cables also have a disadvantage.

They wear down more quickly
from friction--

something Air Moorea
failed to take into account

when drawing up
the maintenance schedule

for the twin otter that crashed.

Bancharel: A stainless steel
cable contains chrome,

which makes it better
at resisting corrosion.

It also contains nickel,

which can make it
more sensitive to wear.

Narrator: Lab results confirm
that the frequent short flights

helped wear away the outside
of the stainless steel cable.

Bancharel:
The stainless steel is worn,
just like on Air Moorea.

The wear was the result

of rubbing against
parts of the plane.

Narrator: It could be
a crucial discovery--

one that finally explains why

a critical control cable
broke in flight.

Investigators suspect friction
weakened the cable

on the twin otter
so much that it snapped

as the pilot was pulling
his elevator up to climb.

Bancharel: At first we first
thought that the cable broke

because of the wear.

That was our first impression,

because the wear
was significant.

Narrator: Bancharel puts
the theory to the test.

She recreates the force
used by santurenne

to pull up the nose
of the plane.

If she's right,
the worn cable should snap.

But it doesn't break.

Bancharel: Once we performed
this test,

we saw that with 50% wear, you
still needed much more force,

a force ten times stronger
than what you'd find in flight

during this phase
of flap retraction.

Bouillard: Thanks to the tests,

we realized that even a cable
worn down by 50%

could have withstood the stress
of the entire flight.

Cable remained intact.

We had to figure out
what phenomenon

could weaken the cable.

Something else helped
to snap that cable.

What?

Narrator: Investigators know
that planes sometimes sustain

hard-to-detect damage from small
impacts with ground vehicles.

If an airport vehicle
accidentally
ran into the plane's elevator,

the impact may have
broken more wires

in the already worn
pitch-up cable.

Bouillard checks the records
at both airports

on the twin otter's route--

Moorea and the larger airport in
Tahiti where it parks overnight.

Bouillard: Thank you.

Narrator: He needs to know if
the plane was ever involved

in an accident.

Bouillard: Nothing.

No impact reported.

We didn't find any evidence of
impact on the control surfaces,

which eliminated the possibility
of contact with another vehicle

during overnight parking.

Narrator: It's another dead end.

There seems to be
no way to explain

why a cable would snap
in flight--

until Bouillard notices
something on the taxiway

at the busy Tahiti airport.

Bouillard: Tell me,
how close do those jets get

to the Air Moorea planes?

We targeted the phenomenon of
the exhaust from a jet engine,

a phenomenon called jet blast.

Narrator: Jet blast is
the powerful exhaust

expelled from jet engines.

The hurricane force winds
can reach speeds

of over 100 miles per hour.

Limore: A plane at full power,

a plane like an Airbus
or like a Boeing,

whose power can flip a plane
a few dozen feet behind it,

it's a phenomenal force.

Narrator: Investigators study
the layout of Tahiti's Airport.

They need to know
if the Air Moorea planes

could have been damaged
by jet blast.

Bouillard: Ok.

The Air Moorea twin otters
are parked here.

Narrator: They learn that
Air Moorea parks its planes

very close to a taxiway
used by powerful jets.

Airports routinely set up
jet blast barriers

to protect planes from
the dangerous force.

There should be barriers to
protect the twin otters

at Tahiti's Airport,
but they've been removed.

Bouillard: Now look at this.

Narrator:
It's an important discovery.

Bouillard:
The jets, they back out here.

These barriers were removed

to make it easier to go from
one parking lot to another.

There was no longer
this physical barrier

to protect
the twin otter planes.

Limore: The Airbus
or Boeing jets were found,

let's say, about 50 meters away
from Air Moorea's parking--

very close.

Bouillard: The Air Moorea planes
are parked

right in the path
of the jet blast.

This plane had been
parked in an area

that was prone
to receiving blasts

from the large carriers
during their departure.

We therefore arrived
at this hypothesis--

that there was
a very high probability

that the cable was weakened
by jet blast.

Narrator: Alain Bouillard learns
that Air Moorea's planes

are especially vulnerable
to jet blast

because of an airline policy
designed to prevent accidents.

The twin otters are parked
with the elevators locked

in a nose-down position.

It makes it impossible
to get off the ground

with the elevators locked.

Limore:
It was locked by a device

that stopped the cables
from moving

and prevented
the elevator from moving.

Narrator: But the nose-down
position likely increased

the damaging effects
of the jet blast.

Investigators suspect that,
like a sail in the wind,

the tilted elevators caught
the full force of the blast,

putting extra strain on
the locked pitch-up cable.

Bancharel:
If the controls are locked,

it pulls and transfers this
energy directly to the cable.

Narrator: They now wonder
if the force of the jet blast

is enough to damage a worn cable
even further.

Another cable test
provides the answer.

Bouillard: There was a cable
worn down by 50%--

a cable that was still able to
resist a hefty amount of strain.

And then a jet blast phenomenon
left the cable so fragile

that it only had one or two
strands left intact.

Narrator: Rather than tearing
the cable completely apart,

the jet blast left
a few strands of wire--

just enough for flight 1121
to take off,

but not enough to survive the
rigors of a seven-minute flight.

Bancharel: They were hanging
by a thread.

Narrator: If the jet blast had
severed the cable completely,

Captain Santurenne would not
have been able

to get his plane off the ground.

But once Airborne,

Captain Santurenne
and his 19 passengers

are one thin strand of wire
away from disaster.

Investigators reproduce
the forces created

as the pilot adjusts
his controls.

Captain santurenne reaches
400 feet and retracts his flaps,

causing his twin otter
to pitch down slightly.

He adjusts his elevator
to pitch back up.

It's enough to snap
the final strand

of the worn and damaged cable.

Bancharel:
He didn't have a chance.

Bouillard: We determined
that the force needed

to correct the pitch
of the plane

was strong enough
to break the last strand.

Narrator: There was nothing
the pilot could have done

to save his plane
and his 19 passengers.

Limore: You can imagine
his reaction--what's going on?

The cable broke,
the control column came back,

and by the time
you analyze what happened,

the plane drops very quickly,

and a few seconds later
you hit the earth.

Narrator: The Air Moorea
accident killed 20 people

and forever changed the lives
of the victims' families.

Bouillard and his team
leave French Polynesia

determined to make it safer
to fly on twin otters.

Bouillard:
The first recommendation

was an urgent request
to check the cables

on all planes equipped
with stainless steel cables.

Narrator: Today there are
tougher maintenance

and inspection standards
around the world

for stainless steel
control cables.

Desjardin: The main lesson
from this investigation,

yes, is the risk of jet blasts
at airports.

Narrator:
The Air Moorea disaster

raised awareness
throughout the industry

of the vital safety role played
by jet blast barriers--

especially at airports that
handle both large jets

and small commuter planes.

Eric Limore hopes
it will be enough

to stop such an accident
from happening again.

Limore: I dare to hope.

If not, what purpose did
this accident serve?

To have 19 passengers die and
have the same thing happen again

without learning anything?

It would be a shame.