Original subtitles

Narrator: A flight over the Amazon

hits severe weather...

Man, translated: Everything was dark as night.

Narrator: And ends in disaster.

Man: The first impression that I got

was the terrible smell of fuel and blood.

Narrator: The search for answers...

Man: We need to take pictures of everything

before it's all gone.

Narrator: ...faces a unique obstacle.

Man: They were taking anything they could carry.

Narrator: A crash site scavenged by looters.

Man: Tires, oxygen bottles, doors,

parts of the landing gear.

Narrator: Missing valuable evidence,

investigators will need all their creativity and cunning...

Man: Got a calculator?

Narrator: ...if they hope to ever discover

why Tans Peru flight 204...

Man: 113 knots.

Narrator: ...fell from the sky.

Man: Keep pulling!

Pilot: Mayday, mayday!

Narrator: The shattered fuselage of a Boeing 737

lies smoldering in a Peruvian jungle.

Stunned passengers struggle to escape the wreckage.

Hector Chaparro Ugarte: Once I was outside

I tried to help those near the door

who knew they had to leave the plane.

Come on! Hurry!

I pulled them by their hair, by their shirtsleeves,

whatever I could get.

Narrator: The plane has gone down

three miles from the nearest airport.

It will take time for rescuers

to fight their way through the thick bush.

Leaking jet fuel could set off a massive fireball

at any moment.

Cesar Castillo Vargas: Fires can appear in a very fast way

not leaving passengers with the possibility to escape.

Narrator: The survivors scramble

to get as far away from the plane as they can.

Chaparro Ugarte: Ten minutes after we left it,

the plane exploded.

Narrator: Scattered wreckage is all that's left

of Tans Peru flight 204...

A flight that just an hour ago

was preparing to take off from the capital city of Lima.

Flight attendant: You'll have to move your seat forward, please.

Narrator: Carrying 91 passengers,

the flight is headed to the river town of Pucalpa

and then Iquitos, gateway to the Amazon.

Castillo Vargas: Taking off from Lima to Pucalpa

was a beautiful flight.

You see the snowcaps on top of the mountains,

the lakes, the little roads

and then you see how it changes color

to the beautiful forest green in the jungle.

Narrator: Hector Chaparro Ugarte barely makes the flight.

A government bureaucrat,

he travels regularly to Pucalpa on business.

Flight attendant: There is extra room three seats down

if that helps.

Chaparro Ugarte: You are too kind.

Chaparro Ugarte: I always have problems on planes

because my legs hit the seat in front of me,

so I always want to be in the emergency exit row

because there's more room.

Narrator: Today, a former Air Force Major

will be handling the takeoff.

Gonzales Chirinos Delgado

is training to become a first officer.

Gonzales Chirinos Delgado: You ready?

Narrator: His instructor is Octavio Perez Palma.

Octavia Perez Palma: Go ahead.

Narrator: A former military commander,

he's now an airline captain.

Chirinos Delgado: Set thrust.

Perez Palma: Thrust set.

Castillo Vargas: Pilots need to build up experience.

A non-experienced pilot would fly

sitting in the first officer position

together with an experienced first officer

sitting on the jump seat.

Narrator: On this flight, the experienced first officer

is Jorge Pinto Panta,

backup for trainee Chirinos Delgado.

Perez Palma: Positive rate of climb.

Chirinos Delgado: Gear up.

Set climb thrust.

Flaps up.

Narrator: Chirinos Delgado's takeoff is perfect.

The 24-year-old Boeing 737 lifts gently into the sky.

Perez Palma: Textbook, major.

Chirinos Delgado: Thank you, sir.

Perez Palma: You remind me of myself.

Narrator: In less than an hour, they should arrive in Pucalpa.

Raymundo Hurtado Martinez: Pucalpa is one of those

great tourist destinations in Amazonian Peru.

Narrator: Foreign tourists and local business people

rely on Pucalpa's small, one-runway airport.

It has no weather radar, so the controllers

rely on pilots flying in the area

to tell them about changing weather conditions.

Perez Palma: This is Captain Perez Palma.

Weather conditions for the flight are good,

but for your safety I'd appreciate

if you could stay in your seats with your seatbelts fastened.

You can sit in the cabin if you prefer.

Narrator: Cruising at 33,000 feet,

the crew contacts the air traffic controller

in Pucalpa for landing instructions.

Perez Palma: Pucalpa tower, Tans Peru 204.

Good afternoon.

We're at 3-3-0 174 DME.

We'll start our descent in ten minutes.

Can you provide conditions, please?

Juan Carlos Flores Peña: Tans Peru 204, tower.

Scattered rains at 3,000, southern quadrant.

Perez Palma: Thank you, Pucalpa tower.

Chirinos Delgado: That front's blowing our way.

Perez Palma: We'll make it.

Narrator: Captain Perez Palma is familiar

with the fickle weather systems of the Amazon,

and he's flown to Pucalpa many times.

52 miles from the airport, the plane hits a storm.

Chaparro Ugarte: I could not understand

why we had to fly through such a storm

because there was really a torrential downpour.

Narrator: In Pucalpa storm clouds are threatening,

but there's still no rain.

Flores Peña: Tans Peru 204.

Charlie Bravo is in the southern quadrant.

Begin final descent to 1,500 feet.

Perez Palma: Pucalpa tower, Tans Peru 204.

Thank you.

Descending to 1,500.

Narrator: As the captain sets the autopilot

to the new target altitude,

another jet arrives at Pucalpa Airport.

The crew reports conditions.

Pilot: Runway 20 looks good so far.

Weather shifting fast.

Suggest caution.

Perez Palma: Okay.

Look at that beast.

It's huge.

It looks like England.

We can get in through here.

Chirinos Delgado: Let's see.

20 miles.

Perez Palma: No, that's too far.

Look. Here's Pucalpa. Do you see it?

Chirinos Delgado: I see it. Maybe through there.

Perez Palma: No. We have to go in further ahead.

Narrator: Now 25 miles from the runway,

the crew has the option of flying to an alternate airport

or returning to Lima.

Perez Palma: Let's get under it.

Chirinos Delgado: Okay.

We're not going to our alternate?

Narrator: But Perez Palma is determined

to make it to Pucalpa.

Chaparro Ugarte: We felt the plane moving from side to side.

It was shaking.

Perez Palma: We are at 2,000 feet.

Castillo Vargas: Pilots would know the altitude to keep.

You would have to go to your minimum descent altitude

based on the procedure approved for Pucalpa at that time.

Narrator: 1,500 feet is the minimum descent altitude

on this flight.

Captain Perez Palma knows he can't go any lower

until he can actually see the runway.

Flores Peña: It's very important

at that altitude and that distance

that the pilot can see the runway so he can land the plane.

Chirinos Delgado: Is there some visibility over there?

Perez Palma: No, not that way.

Stay under the cloud.

Do not descend. Do not descend.

That's what I'm looking for... There. Right there.

Chaparro Ugarte: Everything was dark as night.

Even though it was just 2:45 in the afternoon,

it was so dark it looked like the windows were closed.

Narrator: Perez Palma can sense his trainee is nervous.

Perez Palma: Okay, keep it up.

Narrator: Then, a few miles from the runway....

Perez Palma: Or maybe I have it, okay?

Narrator: The captain decides to take control of the flight.

He turns off the autopilot.

Suddenly, hail hammers the plane.

Perez Palma: Look for the runway.

Look for the runway outside!

Chirinos Delgado: I'm looking. Looking.

Six miles.

Narrator: Captain Perez Palma desperately wants to land,

but he's unable to begin his final descent.

Flores Peña: Until the pilot notifies us

that the runway's in sight,

we cannot authorize him to land.

Perez Palma: Flaps five.

Chirinos Delgado: Okay.

Flaps five.

Perez Palma: Do you have the runway in sight?

Chirinos Delgado: No, I don't have it.

Chaparro Ugarte: I saw a flight attendant come running

and sit in an empty seat.

Flight attendant: We'll be fine.

Chaparro Ugarte: Then I realized that things were pretty serious.

Perez Palma: Tell the tower to confirm visibility

on the other side of the runway

so that we can come around and land.

Narrator: Until he can see the runway,

he's stuck at 1,500 feet.

Chirinos Delgado: Pucalpa tower, Tans Peru 204.

What is the visibility on the other side of the runway?

Flores Peña: Tans Peru 204.

Visibility is getting worse,

now less than two and a half kilometers.

Chirinos Delgado: I can't see it. I can't see anything.

Narrator: An altitude alarm sounds a grave warning.

Inexplicably, the plane has dropped

hundreds of feet in just seconds.

It is now less than 500 feet from the ground.

Chirinos Delgado: Pull it.

Perez Palma: Okay. Pull with me.

Pull!

Narrator: The crew has only seconds to avoid disaster.

Perez Palma: Help me pull!

Flores Peña: Tans Peru 204.

Perez Palma: Pull!

Flores Peña: Tans Peru 204.

Perez Palma: Pull!

Chaparro Ugarte: I believed that these were

the last few minutes of my life.

And as the lights flicked on and off,

I directed myself to god.

Perez Palma: Pull with me.

Pull!

Pull!

Narrator: Tans Peru flight 204

has cut a one-mile-long swath through the jungle,

scattering bodies, luggage and torn pieces of fuselage.

Flores Peña: Tans Peru 204?

Tans Peru?

Tans Peru 204?

Narrator: Flight 204 has not responded to calls

from controller Juan Carlos Flores Peña.

Flores Peña: I had a feeling something bad had happened.

Narrator: The controller's fears are confirmed

when he gets a call from the local fire chief.

Flores Peña: A friend of his was a passenger

who survived the crash, and he called him.

He said the passengers in the front of the plane

were all dead, but there were many survivors in the back.

Narrator: A growing cloud of smoke can be seen for miles.

Many local villagers rush to help,

but some only want to help themselves.

Woman, translated: It makes me so mad.

You know why? They're like rats.

When I went there, I had one thing on my mind--

to help, to help these people, not to steal.

Chaparro Ugarte: Instead of helping people

and finding out whether they were alive,

whether they were dead and seeing how they could help,

they began to loot.

Narrator: Survivors are powerless to stop the looting,

they can only sit and wait for help.

Chaparro Ugarte: And then something incredible happened.

Over here!

A man came out of the trees.

It was like a person coming out of a wall.

Over here!

Narrator: 45 minutes after the crash,

rescuers arrive from Pucalpa.

Chaparro Ugarte: Each minute there was more pain,

and the adrenaline was wearing out.

Narrator: Local reporter Gino Marquez Alvarez

is one of the first journalists on the scene.

Gino Marquez Alvarez: It was incredible to see suitcases

thrown all over the place,

clothes that belonged to the passengers.

It was my first time covering a plane crash as a journalist,

and it affected me deeply.

Narrator: The rescue effort carries on throughout the night.

By morning, the full scope of the disaster becomes clear.

Of the 98 people who boarded the plane,

40 are dead, including all three pilots.

There is no one to explain what happened in the cockpit

during the final seconds of flight 204.

Perez Palma: Pull!

Narrator: This is the fifth fatal crash for Tans Peru

in the last thirteen years.

Julian Palacin Fernandez: Tans Peru was an airline

founded by the government in 1962.

Narrator: The airline has one of the worst safety records

in South America.

Just two and a half years earlier,

all 46 people aboard another Tans Peru flight

died during a failed descent.

Patrik Frykberg: They were flying

from a city called Chiclayo

to another city that is called Chachapoyas,

and just like five minutes before the landing

they crashed against a hill.

Marquez Alvarez: All these facts

turned this into a very big story.

It attracted a huge amount of public attention.

What people wanted were answers.

Why did the accident happen?

Narrator: A team from Peru's

aviation accident investigation commission

must answer that question.

Patrik Frykberg is in charge.

Frykberg: The first impression that I got,

it was the terrible smell of fuel...

And blood.

It was still burning 24 hours after it crashed.

It amazed us that somebody had survived.

Chaparro Ugarte: Thanks to my seat change,

because I couldn't fit into the seat because of my size,

they changed me to row ten, the emergency exit row.

And that's why I had a chance to survive.

Narrator: Frykberg is also amazed by the looting.

Frykberg: They were taking anything they could carry

from the wreckage site.

They took tires, oxygen bottles, doors, metal pieces,

parts of the landing gear.

Maybe there was an interest of exchanging them for money.

Narrator: The small troop of government soldiers

at the crash site...

Frykberg: Excuse me. I'm with CIAA.

I'm gonna need your help, please.

Narrator: ...can't protect all the evidence.

Frykberg: It was huge as well,

so it wasn't that easy of a situation to control.

Frykberg: Hey, I need both these engines

guarded around the clock.

No exceptions.

Narrator: Frykberg is forced to preserve

the most important pieces.

Frykberg: We could distinguish the engines,

but everything else was into small pieces.

We need to take pictures of everything before it's all gone.

Let's go.

Narrator: What he can't guard he tries to document.

Frykberg: I mean, the pieces were there,

the flight controls were there.

We found the cockpit, parts of the cockpit.

We found the seats.

We were mainly worried about recovering

the flight data recorder and the cockpit voice recorder.

Narrator: While the team at the crash site

searches for the vital black boxes,

other investigators interview survivors.

Woman: The last thing that I remember

was just this fire coming from the front end of the plane.

Chaparro Ugarte: It sounded like the engines were struggling.

Woman: I have never seen hail that big.

Narrator: The survivor accounts of the flight confirm reports

of a severe hailstorm that pounded the region...

Perez Palma: It's huge!

Narrator: ...just before flight 204 went down.

Frykberg wonders if the hail somehow disabled the engines.

Frykberg: It can severely damage

the whole aircraft and its systems.

It can shut down the engines.

It's very dangerous for an aircraft

to fly into a hailstorm.

Narrator: In 1988, another 737

flying through a thunderstorm to New Orleans

suddenly lost power to both its engines.

The captain managed to save the plane

with a remarkable emergency landing

on a grass-covered levee.

A storm simulation at an engine test facility

later revealed that intense rain and hail

had caused the engines to fail.

Investigators suspect the same thing may have happened

to flight 204--

that the sheer volume of hail and rain caused a dual flameout.

Castillo Vargas: An engine flameout

is almost like a candle being blown by the wind.

Narrator: A visual inspection of the engines

should help determine if that's the case.

Though the engines' outer casings

have suffered heavy damage,

the turbines are largely intact.

Frykberg: We had to see if they sucked in some debris.

Narrator: A close inspection reveals plant debris

deep inside the turbines.

It means that the engines were spinning

when the plane hit the jungle canopy.

Frykberg: We found that nothing abnormal

had happened to the engines.

They were operating until they crashed.

Narrator: It's conclusive evidence.

An engine flameout did not bring down flight 204.

Frykberg: We didn't know at that time

what had caused the accident.

Narrator: Hope of getting some answers is renewed

when within hours they find one of the plane's two black boxes.

Since Peru lacks the technology to read the data,

the cockpit voice recorder will be shipped

to the NTSB in Washington for analysis.

Frykberg: It's like a rush

because okay, we have something to work with now.

Narrator: But the second black box,

the flight data recorder, is still nowhere to be found.

Frykberg: Any sign of the FDR?

Well, I can guess what happened to it.

Keep looking.

Narrator: It's more than likely that looters have taken the FDR.

Frykberg: Watching that some of the evidence

was being taken away,

we were very, very frustrated

that we could not have a better control of the crash site.

Narrator: With the evidence they need disappearing by the minute,

they post a $500 reward

for the return of the flight data recorder.

Frykberg: It tells us how the engines were

or the systems were performing until they crashed,

until the aircraft crashes,

so it's pretty necessary information to have.

Narrator: Whether they ever get that valuable information

is now up to the people of Pucalpa.

In the meantime, Frykberg gathers information

on what the Pucalpa tower controller witnessed

as he waited for flight 204's arrival.

Flores Peña: At that point, I informed the pilot

of the presence of the cumulonimbus.

In the aviation world, everybody knows

it is the most dangerous cloud.

Narrator: The controller could only warn the crew

about the storm cloud, also known as a Charlie Bravo.

Flores Peña: Tans Peru 204.

A Charlie Bravo in the southern quadrant.

Narrator: In Peru, controllers do not have the authority

to shut down an airport.

Flores Peña: Begin final descent to 1,500 feet.

Frykberg: He was advising the crew

that the conditions were deteriorating fast.

Perez Palma: We can get in through here.

Frykberg: According to his general operations manual,

you either avoid that storm or you go around it

or over it if possible.

Palacin Fernandez: Visual flight rules

instruct a pilot in a situation of zero visibility

to immediately gain altitude and go to an alternate airport.

Narrator: Investigators need to know why Captain Perez Palma

took the risk of flying straight into the storm.

Perez Palma: No. We have to go in further ahead.

Narrator: He had enough fuel to divert to another airport.

They suspect that the unusual origins of Tans Peru

have something to do with his decision.

Launched by the Peruvian Air Force,

the airline fostered a culture that likely came into conflict

with the goals of civil aviation.

Castillo Vargas: Tans Peru started as a military operator

without any certification

from the civil aviation authorities in Peru.

Frykberg: Their personnel were either retired Air Force pilots

or inactive duty pilots.

Hurtado Martinez: Military pilots have

a different type of training than civilian pilots.

For them, if they have to land, it's an order.

They land.

A civilian pilot has more leeway to question.

He has more freedom.

Castillo Vargas: The military attitude

is always to accomplish the mission.

Narrator: The unavoidable question:

Did Perez Palma disregard safety

and endanger the lives of his passengers

in a misguided attempt to finish the mission?

Perez Palma: We'll make it.

Narrator: Looking for more answers,

Frykberg travels to Washington where NTSB specialists

can extract the recording from the CVR.

Chirinos Delgado: Is there some visibility over there?

Perez Palma: No, not that way.

Stay under the cloud.

Do not descend. Do not descend.

Frykberg: I only hear two voices.

Perez Palma and Chirinos Delgado.

Narrator: This was supposed to be a three-man crew,

but there are only two voices on the recording.

Frykberg: Where's the first officer?

Perez Palma: Look for the runway.

Look for the runway outside!

Narrator: But before he can answer that question...

Chirinos Delgado: Six miles.

Frykberg: Oh, hang on.

Hi, it's Patrik.

Narrator: He gets news from his office in Lima.

Frykberg: Call me the second you open it.

The reward worked.

We're getting the FDR.

Narrator: It seems that $500 was too good to pass up

for one man in Pucalpa.

In a major breakthrough for investigators,

the man agrees to exchange the second black box

for the reward money.

Frykberg: He was pretty much the good guy at the time.

Narrator: If it's still functioning,

the FDR could point directly to the cause of the crash

by revealing any in-flight electrical

or mechanical failures.

Meanwhile, the reason why there are only two voices

on the CVR has come to light.

Flight attendant: The first officer was in the cabin.

Narrator: The first officer left the cockpit...

Perez Palma: You can sit in the cabin if you prefer.

Narrator: Because the seatbelt on his jump seat wasn't working.

Castillo Vargas: Aircraft manufacturers

have built their airplanes

to be flown by a crew of two as a minimum.

Narrator: The crew ignored a key rule

requiring the first officer to stay in the cockpit

during a training session.

Frykberg: Turn it up.

Narrator: Frykberg also notices a characteristic sign

that trainee Chirinos Delgado

was not comfortable flying the plane.

Frykberg: Based on other accident investigations,

when we heard the copilot start whistling,

that means that maybe he's in a very stressful situation.

Perez Palma: Look for the runway.

Look for the runway outside!

Chirinos Delgado: I'm looking! I'm looking.

Narrator: Though the investigation is far from over,

it's beginning to look like the pairing...

Chirinos Delgado: Gear down? Perez Palma: Not yet.

Narrator: Of this captain...

Perez Palma: Look at the speed, you idiot!

Narrator: With an inexperienced trainee

may have been a recipe for disaster.

Perez Palma: Do you have the runway in sight?

Narrator: The CVR from Tans Peru flight 204...

Chirinos Delgado: No, I don't have it.

Narrator: Has given investigators a glimpse

inside the cockpit of the doomed flight.

They hope data from the FDR will tell them much more.

But when it is finally examined, those hopes are dashed.

Frykberg: It was like a bad surprise for us

because it was tampered with.

It was opened.

Narrator: The recorder is badly burned,

and whoever found it has toyed

with the intricate internal mechanism.

The device is useless.

Frykberg: The tape was destroyed.

We couldn't use it.

Narrator: It's a bitter disappointment

for investigators.

Frykberg: Alright.

Alright. Thank you.

Narrator: Worse, they're missing some other important data.

Flores Peña: Pucalpa Airport doesn't have radar.

Only Lima Airport does.

Narrator: A radar track of the flight

would show the plane's rate of descent--

information that could tell investigators

how quickly the crisis developed.

Without the radar data...

Frykberg: Got the calculator?

Narrator: ...Frykberg has to get creative.

He listens to how the pilots describe their position.

Frykberg: Okay.

Perez Palma: 20 miles. We are at 2,000 feet.

Narrator: He hopes to recreate the plane's flight path.

It requires detailed analysis.

Frykberg: Uh, 20 DME.

Velocity is 300.

Narrator: He then measures how long it took the plane

to travel a given distance to calculate their air speed.

Frykberg: We made mathematical calculations,

and you obtain the rate of descent.

Narrator: From the analysis, a telling detail emerges.

Frykberg: Look what happens here.

Narrator: 34 seconds before impact,

the plane dropped like a stone,

losing a thousand feet in altitude.

Chaparro Ugarte: It tried to go up,

but instead of going up we saw that the plane

began to fall down, and then we went into freefall.

Narrator: The calculations show that flight 204's

sudden loss of altitude

was accompanied by a rapid loss of speed.

Frykberg: 113 knots in only 38 seconds?

That's when the hail started.

Narrator: The sudden drop in altitude and speed

coincided with the onset of the hailstorm.

Frykberg already knows hail

did not cause the 737's engines to flame out.

Perhaps the hail caused

a different but equally serious problem.

He obtains a high-resolution satellite image

of the thundercloud taken at the time of the crash.

Frykberg: Seeing the size of the storm cell

established that very big hail hit the aircraft.

Frykberg: Look at the radar reflection right here.

This is a hail shaft.

Narrator: Within a hail shaft,

there's a fast moving column of air known as a downdraft.

Flying through one can be risky.

Frykberg: It could either damage the aircraft--

it could even push down the aircraft.

Narrator: In 1985, a Lockheed L-1011 flew

through a cumulonimbus cloud

while on descent to Dallas-Fort Worth Airport.

It was hit by a severe downdraft

and crashed just short of the runway.

A downdraft could explain

flight 204's severe loss of speed and altitude.

But experienced pilots like Perez Palma are trained

to recognize and combat the effects of a downdraft.

Castillo Vargas: He would push the throttles

all the way forward to gain speed.

He would immediately and automatically

would pull the wheel

in order for the airplane to gain altitude.

Narrator: Pulling up the nose of the plane

and applying full engine power

could have kept the plane out of trouble.

Perez Palma: Look for the runway.

Look for the runway outside!

Chirinos Delgado: I'm looking. I'm looking.

Narrator: Investigators must now answer two key questions.

Why couldn't the pilots recover from the downdraft?

And why didn't they notice they were dropping

until alarms began to sound?

Frykberg: They had no idea they were descending.

Castillo Vargas: This is a big mistake.

That's why normally crews come in a set of two

so one looks at the flight instruments

and the other one is aware

of what is going on outside the aircraft.

Narrator: The trainee's inexperience could account

for why he didn't notice that the plane was dropping fast,

but the captain was a highly experienced fighter pilot.

Hurtado Martinez: He was a captain

who had logged a lot of flight hours,

an efficient soldier, even a war hero.

He fought an air battle with a neighboring country

and was given a medal.

Narrator: Perez Palma knew this route.

He was used to flying in unpredictable weather.

It doesn't seem to add up.

Then, while examining photos he took at the crash site,

Frykberg discovers a clue.

He notices that a section of the plane's windshield

is unusually frosted and opaque.

He asks the NTSB to send him photos

of other planes that were damaged by hail.

Frykberg: Hi, it's Patrik...

Statistically, there are a couple of serious incidents

and accidents where hail has been involved.

Narrator: Cockpit windows are made of multiple layers

of acrylic and plastic bonded together.

They are extremely thick and strong,

but in rare cases large hail

can crack the outer layers of the windshield,

creating a frosted texture

that is almost impossible to see through.

Investigators conclude that moments before the crash...

Perez Palma: Look for the runway!

Look for the runway outside!

Chirinos Delgado: I'm looking! I'm looking!

Narrator: The crew was flying blind...

Frykberg: The hail shaft

shattered the front windows of the aircraft

so the crew lost the visual line of sight of the runway.

Perez Palma: Do you have the runway in sight?

Narrator: Hindered by the damaged window...

Chirinos Delgado: No. I don't have it!

Narrator: The crew failed to notice

what the flight instruments were telling them.

The plane was falling fast, pushed by a downdraft.

Once they hit 500 feet, they couldn't help but notice.

The sound of the altitude alert warning

began filling the cockpit.

Commercial jetliners are equipped

with a ground proximity radar system.

It triggers a warning if the plane flies too low

without deploying its landing gear.

Perez Palma: Pull with me! Pull!

Narrator: It's clear from the flight 204 CVR

that the pilots were trying to pull up,

yet the plane didn't climb.

The question is why.

Frykberg: We asked the national transportation safety board

if they could do a background sound analysis

so we could establish if the engines

were at max power or not.

Perez Palma: Look for the runway!

Narrator: One by one, the various sounds in the cockpit

are identified and eliminated.

Frykberg: That's only the engines, right?

Narrator: If the pilots were trying to climb,

the engines should be screaming as they rev up,

but that's not what investigators hear.

Frykberg: They're not spooling up.

You just hear constant frequency until the end.

Narrator: It seems the crew failed to do the one thing

that could have saved the plane:

Perform a standard procedure-- accelerate out of trouble.

Frykberg needs to know

how they could have made such a fundamental error.

He reviews the events leading up to the crash,

a perfect storm of unlikely events and tragic mistakes.

It starts...

Perez Palma: You can sit in the cabin if you prefer.

Narrator: ...with the broken seatbelt

on the first officer's jump seat.

The captain is left flying

with only a young, inexperienced trainee.

Perez Palma: Textbook, major.

Chirinos Delgado: Thank you, sir.

Perez Palma: You remind me of myself.

Chirinos Delgado: Look at that beast.

Narrator: Captain Perez Palma misjudges the storm...

Perez Palma: We can get in through here.

Narrator: ...and flies right through it.

Narrator: Intense hail shatters the windshield...

Perez Palma: Do you have the runway in sight?

Narrator: ...blinding the crew.

Chirinos Delgado: No. I don't have it.

Narrator: When a massive downdraft hits,

the pilots don't notice their plane is descending

until the ground proximity alarm goes off.

Then they make the biggest mistake of all--

they fail to throttle up.

Investigators conclude that happened

as the result of one critical decision

taken moments earlier by Captain Perez Palma.

Frykberg: It sealed their fate.

Narrator: Investigators analyze a pivotal decision

made by the captain of flight 204

less than a minute before the crash.

Frykberg: At the last moment he took control.

Narrator: When he began to lose confidence in his copilot...

Perez Palma: Or maybe I have it, okay?

Narrator: He took command

and became the pilot flying the plane.

At that moment Chirinos Delgado became first officer.

Chirinos Delgado: Gear down?

Perez Palma: Not yet.

Narrator: The pilots have switched roles.

Perez Palma: Look at the speed, you idiot!

Narrator: Both seem confused by the transition.

Perez Palma: Hurry with the flaps.

Narrator: It's now the co-pilot's job

to monitor the changes in altitude.

Perez Palma: Flaps five.

Chirinos Delgado: Okay, flaps five.

Narrator: But he's distracted by the demands of the captain.

Castillo Vargas: Never both pilots are looking outside

at the same time, never.

Always one of the pilots

must keep close contact with the instruments.

Chirinos Delgado: I can't see it! I can't see anything!

Pull it!

Perez Palma: Okay. Pull with me.

Narrator: Though both pilots were pulling back,

they both likely assumed the other one would take

the crucial second step needed to get out of trouble--

pushing the throttles forward to maximum thrust.

Hurtado Martinez: When pilots are too confident

and self-sufficient,

they get used to the idea that nothing will happen.

Perez Palma: We'll make it.

Hurtado Martinez: Call it lack of discipline

or not obeying the rules, but that's what happened.

Narrator: When investigators examine the Tans Peru accident

that occurred two and a half years earlier,

they discover a shocking fact.

Palacin Fernandez: The recommendations from the accident in Chachapoyas

were not implemented,

and the result was the same type of accident in Pucalpa.

Narrator: Tans Peru flight 222 to Chachapoyas

also crashed on approach for many of the same reasons,

especially the failure to follow visual flight rules.

Palacin Fernandez: These rules were violated in both cases

and caused two tragic air crashes.

Frykberg: There's absolutely nothing wrong...

Narrator: But before investigators can finish their work...

Frykberg: The company had another serious incident.

They almost had a midair collision

with a commercial airline.

Narrator: ...the Peruvian government steps in

to close down Tans Peru airline.

Less than a year after the crash,

authorities release the official report.

The major cause of the accident--pilot error.

Perez Palma: Let's get under it.

Frykberg: It was the loss of situation awareness.

Chirinos Delgado: We're not going to our alternate?

Frykberg: The violation of their procedures caused this accident.

Narrator: Flying into a storm,

flying without a qualified first officer in the cockpit,

failing to react properly to an emergency--

all are significant errors.

Castillo Vargas: We should never

forget that training...

Is the only guarantee for pilots

to do the right thing.

Preparation must include

an attitude, a culture,

a safety culture that they need

to very deeply understand