All language subtitles for Air.Disasters.S15E08.No.Warning.1080p.AMZN.WEB-DL.DDP.2.0.H.264-OGRE_track4_[eng]

Narrator: On approach to a remote town

in Indonesia's Papua province...

First Officer: Gear down.

Narrator:...a turboprop plane vanishes.

Controller: Trigana 267, Oksibil.

Do you copy?

[Man, Translated]
We tried to think positively

that there's a chance the
aircraft ended up landing

at a different airport
with limited communication.

News Anchor: Overseas a search is underway

for an Indonesian plane
carrying more than 50 people.

Narrator: A treacherous
climb up a steep mountain

leads to the worst possible news.

Investigator: We've reached the crash site.

No survivors.

Man: The number one
priority is to find the black boxes.

Narrator: With no clues, investigators hope

the damaged black boxes
will solve this puzzling case.

Man: Can you turn that up?

[Humming]

That's it?

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 into this tragedy.

Man: He's gonna crash!

♪

[Tires Screech]

♪

♪

Narrator: Sentani airport
in Papua province, Indonesia.

Trigana air service pilots

Captain Hasanuddin
and first officer Aryadin

are on a short layover
before their fifth flight of the day.

Hasanuddin: What have we got?
Like 20 minutes?

Aryadin: About that, yeah.

Hasanuddin: I think I'll
get up and stretch my legs.

Want anything from the terminal?

Aryadin: I'm okay, thanks.

Hasanuddin: Okay.

Narrator: The pilots have already flown

four short flights today.

This leg will take them
back to a remote airport

in the Oksibil area.

Todd Curtis: Typically,
the flights of a commuter aircraft

will be an hour or less.

So the typical duty day for a pilot

might include four
or more takeoffs and landings.

It's challenging in the
sense of taking off and landing

are the most risky
parts of any aircraft flight,

and doing so several times in a day

could put different
kinds of stresses on a pilot.

Dita Amelia Kurniawan: Hello.

Narrator: Flight attendant
Dita Amelia Kurniawan...

Kurniawan: Good afternoon.

Narrator:...has been
with Trigana Air Service

for three years

and knows many of the
regulars who fly this route.

Kurniawan: Good to see you again.

Narrator: 49 passengers
will be making the short trip

to Oksibil.

Gerry Soejatman:
Oksibil is a very remote area,

so most of the passengers
would be local government officials,

local businessmen.

Very few tourists go to Oksibil.

♪

Hasanuddin: Do you want
to switch on the way back?

Aryadin: No, I'm good for one more leg.

[Phone Rings]

Hasanuddin: All set back there, Dita?

Kurniawan: Good to go.

Hasanuddin: Thank you, Dita.

[Engines Revving]

Narrator: At 2:22 pm, Flight 267 takes off.

Aryadin: Landing gear up.

Hasanuddin: Landing gear is up.

Aryadin: Flaps set to zero.

Hasanuddin: Flaps zero.

Narrator: The flight
to Oksibil takes 40 minutes.

The estimated arrival time is 3:04 pm.

Hasanuddin: We're at 2,000 feet.
Want to turn on the autopilot?

Aryadin: Autopilot engaged.

Narrator: The pilots
are flying an ATR 42-300,

a twin-turboprop short-haul aircraft.

Curtis: The ATR 42 is

a medium capacity commuter-type aircraft.

They're popular because they
can get into smaller airports,

places where you
can't really get an airplane

that's a 737 or 747 size
into and out of the airport.

Narrator: Minutes later, the plane reaches

its cruising altitude of 11,500 feet.

[Ding]

Kurniawan: Water?

Narrator: The flight is so short...

Hasanuddin: I'll call Oksibil.

Narrator:...the captain
is already preparing

for the descent into Oksibil.

Hasanuddin: Oksibil, Trigana 267.

Controller: Trigana 267, Oksibil, copy.

Hasanuddin: We are beginning our approach.

We would like to descend from 11,500 feet.

Controller: Confirm descent from 11,500.

Let me know when you
are positioned over Oksibil.

Narrator: Oksibil is a small
airport situated in a valley.

The mountains surrounding
it can reach 11,000 feet.

Aryadin: Decreasing engine thrust.

Hasanuddin: 244 knots and dropping.

Curtis: Oksibil airport is
in a mountainous area.

It sits in a valley.

And on top of that,
they have very limited navigational aids

at that airport.

Narrator: Without the aid
of advanced landing systems

seen at bigger airports,

pilots flying into Oksibil
must keep the runway in sight

during the approach.

Curtis: A visual approach,
as the name implies,

is an approach where the flight crew

has to have the airport
and the surrounding area in sight.

Hasanuddin: Cabin crew prepare for landing.

Kurniawan: In preparation,

please straighten your
seatback and stow your tray.

I'll be coming around to collect
any garbage you may have.

Hasanuddin: Big plans with the family?

Aryadin: Yeah,
looking forward to some time off.

Hasanuddin: Yes.
It's been very busy these past few weeks.

♪

Aryadin: Flaps 15.

♪

♪

Gear down.

♪

♪

Controller: Wings Air 1250,
confirm descent from 12,000.

Report when you are
positioned over Oksibil.

Narrator: Five minutes later,

The air traffic controller
at Oksibil realizes

Flight 267 hasn't reported in as expected.

Controller: Trigana 267, Oksibil.

Do you copy?

Trigana 267, Oksibil.

Do you copy?

[Static Hiss]

Curtis: One of the
common things that happens

when an airplane doesn't
land at an airport for some reason

is they may divert to another airfield.

The crew landing the aircraft

may have been too busy to call the airport

before diverting to another airfield.

Controller: Hey, this is Oksibil.

We've lost contact with Flight 267.

Have you heard from the pilots?

You haven't?

We might have a problem here.

Narrator: Word of the
missing plane travels fast.

News Anchor: Overseas a search is underway

For an Indonesian plane
carrying more than 50 people.

The flight lost contact today

over a remote area of the country.

Narrator: As the news spreads,
investigators with Indonesia's

National Transportation Safety Committee,
the KNKT,

fear the worst.

Ray Nurcahyo: My first impression

was that something wrong had happened.

It's not looking good.

Ony Wibowo: Well, maybe they just diverted

and haven't checked in yet.

[Translated] We tried
to keep thinking positively

that there's a chance the aircraft

suffered from some damage

and ended up landing at a different airport

with limited communication.

Narrator: A search
and rescue team is assembled,

consisting of army soldiers
and search and rescue personnel.

Wibowo: They immediately began the search

around Oksibil airport

Because we learned from air traffic control

that its last location was
quite close to the airport.

Narrator: Flight 267 was
only 15 miles from Oksibil Airport

when it last checked
in with air traffic control.

But search efforts come up empty...

until a pilot flying out of Oksibil Airport

spots smoke billowing
from nearby Tanggo Mountain.

Woman, Translated: We
don't have a lot of information.

We can only hope that the
people on board have survived.

Narrator: The day after a
pilot reported seeing smoke

in the mountains surrounding Oksibil,
Indonesia,

the crash site of Trigana
Flight 267 is located.

[Phone Rings]

Nurcahyo: Yeah.

1-4-0 degrees, 29 minutes,

51.18 seconds east.

Okay, got it. Thank you.

Narrator: The wreckage is
at approximately 8,300 feet

on a ridge of Tanggo Mountain,

10 nautical miles from Oksibil Airport.

Wibowo: They went off course.

How did they end up over there?

Nurcahyo: We need
to get eyes on that crash site.

I'm gonna send one of our guys up.

♪

Narrator: A search and rescue team

takes a KNKT
investigator to the crash site.

At over 4,000 feet above ground level,

there are no roads, runways or clearings.

The only way to get
to the crash site is on foot.

Nurcahyo: To reach the area,
the team had to walk

for about four and five hours.

They had to climb in a quite steep,
the dense vegetation.

It's quite hard to get to the site.

Narrator: After climbing for five hours,

the team finally reaches the crash site.

A field of debris stretches
through Tanggo's thick forest.

♪

♪

♪

♪

[Phone Rings]

Nurcahyo: Go ahead, Oksibil.

Investigator: Jakarta,
we've reached the crash site.

No survivors.

Nurcahyo: Okay.

Once you catch your breath,

the number one priority
is to find the black boxes.

Investigator: Okay.

Hey, guys.

Check it out.

We're looking for the FDR and the CVR.

Narrator: Because of the remote location,

bringing much of the
wreckage down from the mountain

will be impossible.

So the investigator at the scene
must document as much as he can

and send photos back to headquarters.

[Click]

While the search and rescue team

retrieves the remains of
the 54 people who died...

The KNKT investigator tries to determine

exactly how the plane hit the mountain.

The trees surrounding the crash site

provide an important clue.

They are sheared off in a straight line,

indicating the plane flew
head-on into the mountain.

Investigator: That's right.
There's no sign they pulled up.

Narrator: How could the crew have flown

straight into a mountain
that's so well known to pilots?

The investigation
team's top priority will be

to figure out what was
happening in the cockpit

at the time of the crash.

♪

The plane's flight data
recorder and cockpit voice recorder

can be invaluable
tools for the investigation.

♪

♪

The damaged black boxes
are shipped out for analysis.

♪

♪

In the days that follow...

family members mourn

while they wait for the
recovery of loved ones.

[Speaking Indonesian]

Man, Translated: Search and rescue,

along with the local help,

have been successful
in retrieving the 54 bodies.

Narrator: They are desperate
to know what caused the crash

that killed everyone on the flight.

It's up to KNKT
investigators to figure that out.

They first need to determine
why the plane ended up off course.

Nurcahyo: Blue's the flight
path in the approach chart.

Here's where they crashed.

Narrator: Flight 267
crashed about 10 miles west

of the approach path into Oksibil airport.

Nurcahyo: They went
right and ended up here.

Wibowo: I'd like to know more
about the terrain around here.

Narrator: To determine
the height of the terrain

along the flight's path,

investigators use special software

That generates
topographical data for the area.

Wibowo: When we learned
about the location of the crash,

we had some difficulties.

We realized it would be a challenge for us

to identify the terrain
height of the plane's debris.

[Sighs]

Narrator: The topographical map reveals

that the pilots were
flying a treacherous route.

Nurcahyo: They were surrounded by mountains

as high as 9,000 feet.

Wibowo: Why didn't they fly above them?

Narrator: Investigators wonder

if there was a mechanical
problem with the plane

that caused it to plow into a mountain.

Nurcahyo: Maybe the FDR can tell us.

Curtis: Certainly there
would have been something

in the flight data recorder

that may have given an indication

that some system on the aircraft

wasn't operating as it should have.

Narrator: When the
recovered flight data arrives,

Nurcahyo and Wibowo
are eager to get their first look

at how the plane was
functioning at the time of the crash.

Nurcahyo: Wait a minute.

This doesn't make any sense.

This says the plane was going east,
not south.

[Speaking Indonesian]

Wibowo: We were able to download this data

that contained all the flight information,

but the flight data we
recovered didn't correlate

with what might have
happened on the day of the crash.

And the time of day is wrong.

So is the speed.

The flight data was not
from the day of the accident.

Narrator: Digging
even deeper into the data,

the investigators come
to a disturbing realization:

the recorder wasn't
working at the time of the crash.

Nurcahyo: Useless.

We found that the FDR

had been experiencing
several problems since 2012.

It had been installed on that aircraft

and found fault and then offloaded,

went to the shop for repair,
back again to the aircraft.

Narrator: The malfunctioning FDR

had no connection to the accident,

making it much harder
for Nurcahyo and Wibowo

to figure out what caused it.

Investigators still don't know

why Flight 267 slammed
into the side of a mountain.

In the Indonesian province of Papua,

the families of the 54 people
on board Trigana Flight 267

lay their loved ones to rest...

including flight attendant
Dita Amelia Kurniawan.

Overcome by grief,
they want answers as to what happened.

News Anchor: Authorities
have released new pictures

showing the wreckage from the
Indonesian passenger plane

that crashed in the
country's remote eastern region

over the weekend.

Narrator: KNKT investigators
are facing intense pressure

to determine why Flight 267 crashed.

Without recorded flight data,

the plane's cockpit voice recorder

is investigators' last hope
to learn what was happening

in the air at the time of the crash.

Curtis: They would be able to understand

what was said
to and from air traffic control,

and they can also understand
any kind of communication,

formal or informal,
that was taking place within the cockpit.

That can be a huge indicator

of something going wrong with that flight.

Narrator: Fortunately,
the CVR data is successfully recovered.

Nurcahyo: Alright, we're ready?

Okay, play it.

Narrator: The CVR
contains two hours of audio,

including from the two
flights prior to the accident flight.

Hasanuddin: I'll call down and let
them know we're coming.

Narrator: Investigators first listen

to the pilots' flight
into Oksibil from earlier in the day,

in the hopes of finding clues.

Aryadin: Oksibil, Trigana 267.

Controller: Trigana 267, Oksibil, copy.

Aryadin: We are beginning our approach.

We would like to descend from 11,500 feet.

Controller: Confirm descent from 11,500.

Let me know when you
are positioned over Oksibil.

Aryadin: Uh, Oksibil,
we won't be over the airport.

We're going to fly direct
to a left base leg to runway 11.

Controller: Copy that.

Nurcahyo: Left base leg?

That's not what it says in the charts.

Wibowo: They took a shortcut?

Narrator: The CVR reveals that the pilots

made an intentional
deviation in their approach

during their prior flight into Oksibil.

The official approach directs aircraft

to fly over the airport
and then circle back and land.

But on the earlier flight, the pilots flew

directly to runway 11...

without looping around.

Aryadin: 500 feet.

Landing flaps and propeller
speed are set and confirmed.

Narrator: After flying
the shorter approach,

the pilots landed
on the runway at Oksibil...

without incident.

Investigators wonder if the pilots tried

to repeat that shorter
approach a few hours later,

but with a very different result.

Nurcahyo: Let's skip
ahead to the accident flight.

Hasanuddin: We're at 2,000 feet.

Want to turn on the autopilot?

Aryadin: Autopilot engaged.

Controller: Confirm descent from 11,500.

Let me know when you
are positioned over Oksibil.

Hasanuddin: Oksibil, we're flying direct

to a left base leg to runway 11.

Controller: Copy that.

Nurcahyo: So they take the same shortcut

for the accident flight.

Narrator: The last flight proceeds

much like the crew's
earlier flight into Oksibil.

Hasanuddin: Big plans with the family?

Narrator: Investigators listen
closely for any signs of danger.

Aryadin: Yeah,
looking forward to some time off.

Hasanuddin: It's been very
busy these past few weeks.

Narrator: It's what they
don't hear that raises questions.

Wibowo: They're not doing their
approach briefing and checklist.

Curtis: Briefings and checklists
serve several functions.

One of the key functions
is to give the flight crew

a better understanding
of their environment.

Not doing that makes it less likely

that the pilot will
remember to do certain things,

or to take certain precautions,

or to be aware of certain hazards

that could be happening
on that particular flight.

Narrator: The team now knows that the crew

missed a crucial step on their approach.

But can the recording reveal anything

about how the plane was
functioning mechanically

just before the crash?

Nurcahyo: Can you turn that up?

[Humming]

Picking up anything with the engines?

Wibowo: We tried to analyze
the sound of the engine.

Hasanuddin: Flaps 15.

Gear down.

Wibowo: Based on the
frequency and amplitude

of the sound of the propeller,

we concluded that the engine and propeller

were both in good shape.

Nothing unusual.

Nurcahyo: On the last phase of the flight,
the CVR recorded

that the condition
in the cockpit was normal.

Narrator: While listening
to the final moments of the crash,

investigators make a baffling discovery.

[Recording Stops]

Nurcahyo: That's it?

Normally at the last second of the flight

the pilot would have
been scream or do something.

It happened so fast.

It sounds like they didn't
even see the mountain.

♪

♪

[Crash]

Narrator: Investigators have a theory

about the crash of Trigana Flight 267.

They believe that weather

may have obscured the
pilots' view of the mountain.

The team scrutinizes weather data recorded

less than an hour before the crash.

Wibowo: Oksibil was
covered by dense clouds.

Narrator: The data reveals
that at the time of the accident

Flight 267 would have been flying

through an area of low clouds.

Nurcahyo: The clouds could
have been quite dense here.

The pilots wouldn't
have been able to see much.

Wibowo: Yeah, but you know Papua.

You never really know what
the weather is gonna be like

unless you're looking
out the window yourself.

Soejatman: It is difficult to determine

whether the flight was
in cloudy conditions or not.

In the mountainous area it
can be cloudy in one valley,

it can be perfectly
clear in another valley,

and you go into another
valley and it's completely covered.

Narrator: To get a firsthand account

of the weather conditions
on the day of the accident,

investigators speak
to the controller on duty.

Nurcahyo: What was the weather like

on their first flight into Oksibil?

Controller: It looked mostly clear.

Nurcahyo: And did the weather
change on their second flight?

Controller: Yeah. The clouds rolled in.

It was so dense that I
couldn't even see the mountains.

Narrator: The controller
tells the investigators

that he did inform the pilots
about the cloudy conditions.

Hasanuddin: Oksibil, Trigana 267.

Controller: Trigana 267, Oksibil. Go ahead.

Hasanuddin: How's the
weather looking for our approach?

Controller: You've got a
cloud base of 8,000 feet.

Narrator: The pilots'
decision to continue flying

with so much cloud
cover surprises investigators.

Wibowo: In principle,
when flying using visual rules,

only one rule applies:

to arrive safely

you must maintain
visual contact at all times.

Aryadin: Gear down.

Nurcahyo: The visual
approach is not allowed to be done

in a cloudy condition,

so when the cloudy condition

and they're unable
to see the whole mountain,

they should follow the procedures.

Narrator: But instead
of following procedure...

Nurcahyo: They knew the
base of the clouds was 8,000 feet.

Narrator:...they took a gamble

that they would eventually
catch sight of the runway.

Nurcahyo: They were descending,

expecting to drop out
of the clouds at any minute.

Wibowo: Instead, they crash into a mountain

at 8,300 feet.

♪

♪

We still don't know why they didn't know

they were in the path of a mountain.

Narrator: With modern aviation technology,

even if the pilots didn't see the mountain,

the plane should have.

So why didn't they know they
were heading straight into one?

Nurcahyo: We need
to check their warning system.

[Speaking Indonesian]

Wibowo: When a plane is
in close proximity to terrain

or about to hit an object,

there's a warning
system that warns the pilot

when the plane is very close to terrain.

Narrator: The warning system
uses GPS and a terrain database

to monitor an aircraft's height

above the surrounding terrain.

If the plane comes too close to the ground,

the system will warn the
flight crew with audio messages...

Computer: Terrain, terrain. Pull up!

Narrator:...so pilots know
to increase their altitude.

Nurcahyo: This is the
profile of the mountain.

This is our flight
descending through clouds,

and the pilots can't see
the ridge in front of them.

Their proximity to the terrain

would have activated
the terrain caution here,

60 seconds before impact.

Now, the pull-up warning
should have gone off here,

30 seconds before.

Were there any warnings
going off in the cockpit?

Wibowo: No.
There's nothing in the transcript.

Narrator: The absence of audible alerts

leads investigators to wonder

if the plane's warning
system was working properly.

The team knows the FDR
wasn't properly maintained.

Could the same be true
for the warning system?

Wibowo: We tried to dig
deeper to see if the warning system

had been properly installed in Trigana 267.

Nurcahyo: Last maintenance
was performed on August 14th,

two days before the crash.

It appeared to be working normally.

Wibowo: When we looked
into the maintenance record,

We did not find any significant mention

of something broken in the warning system.

Narrator: With a faulty
warning system ruled out,

investigators now wonder

if the terrain data used
by the system was accurate.

Nurcahyo: This area
is not very well mapped.

Some of the Papua area was very rough data.

The precision of the data

was not as close to the actual conditions.

Soejatman: If you fly
in a mountainous area,

the database itself might not detect

the fine details of the
contour of the terrain around you.

Narrator: Did the lack of
accurate terrain data mean

the system wasn't able to warn pilots

when they were too close
to the mountainous terrain?

The Trigana 267 investigators

decide to speak with Trigana pilots

who regularly fly in the Oksibil area

to find out if they
received terrain warnings.

The pilots report that not only
did the system provide warnings,

It gave an excessive
amount of false warnings

due to the poor quality terrain data.

Soejatman: If you're flying
within a mountainous area,

it can give you a false
warning or unnecessary warnings.

Wibowo: Was this
area prone to false alarms?

Soejatman: Imagine you are trying to land

in a small airport
in the middle of the valley.

You can see the airport in front of you.

You're in visual conditions,

and then the system
starts giving you a warning.

Computer: Terrain, terrain. Pull up!

Soejatman: You think, well, I can see

the airport in front of me.

I can see the terrain behind it.

That, that warning is, is annoying.

Wibowo: And what do you normally do

when you keep getting these false warnings?

Hold on.

He says sometimes

they deliberately pull the circuit breaker.

Sorry, go on.

Narrator: It's an astonishing finding.

Curtis: It might have
been because of spurious

or inappropriate warnings by the system.

That is, it's telling you
that you're close to the ground

when in fact you're not.

This is what I like to call the
"Boy Who Cried Wolf" syndrome.

Computer: Terrain, terrain. Pull up!

Curtis: You know,
the other flights we've done,

we've had no problem.

Let's just turn this thing off.

Computer: Terrain.

Soejatman: But if you
pull the circuit breaker,

you might forget that you've pulled it.

And that's not good,

because if you're going
into a valley when it's still cloudy,

you still need your systems

no matter how unreliable that is.

Any warning you get,

if you don't have visual
contact with the ground,

You follow it.

Wibowo: Okay, thank you.

They just pull the breaker
to get rid of the false warnings.

Apparently it's common practice.

Nurcahyo: Are you kidding me?

Narrator: This revelation
leads investigators

to ask themselves a difficult question.

Did Flight 267 lack terrain warnings...

because the pilots
intentionally turned the system off?

Curtis: Both the
captain and the first officer

were very experienced.

In fact, I think these pilots
were much more experienced

than the average turboprop pilot.

Hasanuddin: We've
reached cruising altitude, 11,500.

Wibowo: Is it possible
the pilots were overconfident

because they had flown this route so often?

Nurcahyo: We also asking
questions to some pilots,

particularly pilots that had experience

flying with these two accident pilots.

Wibowo: Will you excuse me?

I now have a pilot on the line

that says he's personally
seen Captain Hasanuddin

pulling the circuit breaker.

Nurcahyo: We found some information

that some co-pilots flying with the captain

knew the captain had the
habit to inactivate the system.

Hasanuddin: Decreasing engine thrust.

Computer: Terrain, terrain. Pull up!

Hasanuddin: Yeah, yeah, yeah.

Computer: Terrain, terrain.

Curtis: Overconfidence and complacency

are two of the issues
that are common in aviation,

and what it leads to

is certain equipment could be turned off

because the pilots
think that their experience

in other aspects of flight
will more than compensate.

Computer: Terrain, terrain.

Hasanuddin: Yeah, yeah, yeah.

Curtis: When a flight
crew operates deliberately

with an aircraft that's not fully capable,

They're increasing the risk of that flight.

♪

Narrator: Looking
through the captain's records,

investigators discover
that the airline knew about his habit

of pulling the circuit breaker.

Nurcahyo: Hmm.

It says here that they scheduled

a briefing with him to address it.

Based on this information,

we assumed that that day,
on the accident day,

the captain also inactivated the system.

Computer: Terrain, terrain.
Pull up! Terrain, terrain.

Hasanuddin: I got this.

Computer: Pull up!
Terrain, terrain. Pull up!

Narrator: Investigators
now believe that the pilots

intentionally disabled their warning system

on an earlier flight that day...

and then never reset it.

Nurcahyo: If the system was active,

I'm sure that the accident
would have been avoided

Because the last seconds
of the flight before the impact,

the system will scream "Pull up, pull up!"

The pilot would have
taken action to save the flight.

[Crash]

Narrator: No wreckage
relating to the warning system

is recovered from the crash site.

Investigators can't know for sure

if the circuit breaker had been pulled.

But even if the pilots
were overly confident

they could make the approach

without the aid of the warning system,

there's still something
else that doesn't add up.

Nurcahyo: The pilots flew
into this area all the time.

Why were they flying
so close to the mountains

in the first place?

Narrator: Investigators
are trying to determine

why pilots who were very
familiar with the Oksibil area

would risk flying so close
to the mountains below them.

Nurcahyo: Can you pull
up this approach chart?

♪

Narrator: A diagram in the
corner of the approach chart

informs pilots about the
safe minimum altitudes

in areas surrounding the approach path.

Nurcahyo: The approach chart
says the minimum safe altitude

in this area is 8,000 feet.

Flight 267 crashed at 8,300 feet.

Curtis: They were adhering
strictly to the information

that was there in the approach chart,

but the information was wrong,
and that wrong information

put them at risk
for colliding with terrain.

Hasanuddin: We're good to 8,000 feet.

Narrator: Investigators
believe the pilots were aware

of the minimum safe altitude
published on the approach chart.

It's the last piece of the puzzle.

Nurcahyo: The crew thinks
they're safe down to 8,000 feet.

And on the accident day,

the base of the clouds is 8,000 feet.

Wibowo: It makes the pilots feel

as long as they're in the clouds,
they're safe.

Aryadin: Decreasing engine thrust.

Hasanuddin: 244 knots and dropping.

Cabin crew, prepare for landing.

Curtis: What struck me more than anything

was that this was so very preventable.

This was a controlled
flight into terrain event.

Narrator: The investigation has uncovered

a confluence of factors
that led to the crash of Flight 267.

Hasanuddin: Big plans with the family?

Aryadin: Yeah,
looking forward to some time off.

Hasanuddin: It's been very
busy these past few weeks.

Narrator: At the core:

two pilots who had grown overconfident

flying the route so many times before.

Computer: Terrain, terrain. Pull up!

Terrain, terrain. Pull up!

Terrain, terrain. Pull up!

Terrain, terrain.

Hasanuddin: I got this.

Computer: Pull up! Terrain, terrain.

Narrator: Because the
captain had a reputation

For pulling the ground proximity
warning system circuit breaker,

investigators suspect
he disabled the system

on an earlier flight that day.

Then, on the last flight into oksibil...

Aryadin: We're beginning our approach.

We would like to descend from 11,500 feet.

Controller: Confirm descent from 11,500.

Let me know when you
are positioned over Oksibil.

Aryadin: Gear down.

Narrator: The pilots failed
to do their approach briefing

or safety checks and relied
on faulty approach charts.

Curtis: There are three key things

that could have avoided this accident:

adherence to standardized procedures,

the use of warning systems,

and the use of cockpit
resource management techniques,

which could be as simple as,

is there a checklist that should be used?

♪

[Crash]

Three very clear areas

where any one of them would
have prevented this accident.

None of them happened.

Narrator: In the aftermath of Flight 267,

the KNKT makes a series
of safety recommendations

that will make the
skies of Indonesia safer.

Soejatman: First of all,
the charts needed to be updated.

Wibowo: We also asked the airline operator

to request the database
for the warning system

to be updated with a more accurate version.

Up to now we noticed a significant drop

in warning system violations.

Also, since the approach
chart for Oksibil has been fixed,

we've seen a positive impact
in terms of flight safety in Papua.

[Speaking Indonesian]

Curtis: The lessons from this accident,

the insights from the
investigation won't go away.

They'll be here decades from now.

I'm confident that the
insights in this report

will influence design of equipment,

Will influence the design of procedures,

will influence the kind of hazards

that flight crews will
look out for in the future.