Original subtitles

Airfield in sight.

Runway in sight.

A Boeing 737 crash lands in a night storm.

A Boeing 737 crash lands in a night storm.

It ended up impacting the ground short of the runway.

It ended up impacting the ground short of the runway.

A late-night takeoff in Beirut...

Ah!

Ah!

...turns to horror.

The plane was out of control.

The plane was out of control.

The crew was never fully on top of what was happening.

The crew was never fully on top of what was happening.

A jetliner plummets to the ground

- in the Swedish Arctic. - Mayday!

Mayday!

Mayday!

Investigators uncover evidence that the pilots were

disoriented in the darkness.

Help me, please!

Help me, please!

I don't know.

I don't see anything.

It begins to get confusing.

And if you get past a certain point,

And if you get past a certain point,

that confusion can become terminal.

Three different crews fall into the same trap

Three different crews fall into the same trap

in the dead of night.

250, do you have the runway in sight?

250, do you have the runway in sight?

Ladies and gentlemen, we are starting our approach.

We lost both engines.

Emergency respond.

Emergency respond.

Mayday!

Mayday!

Brace for impact!

It's gonna crash!

It's just after midnight 36,000

feet over the Caribbean Sea.

feet over the Caribbean Sea.

AIRES Flight 8250 carries tourists

and locals from Bogota to the small Colombian island

and locals from Bogota to the small Colombian island

of San Andres.

So much for grabbing dinner on the ground.

Yeah, it's gonna be a late night.

Yeah, it's gonna be a late night.

Captain Wilson Gutierrez has almost

20 years of flying experience.

20 years of flying experience.

First Officer Camilo Pineros has flown for AIRES

for more than three years...

for more than three years...

the last on the airline's new Boeing 737s.

Looks like there's some weather ahead of us.

Let's keep an eye on it.

Airlines operate 24 hours a day,

so pilots fly in all kinds of conditions,

so pilots fly in all kinds of conditions,

both daylight, dark, good weather, bad weather.

The flight from Bogota to San Andres

The flight from Bogota to San Andres

takes an hour and 40 minutes.

Tonight, they'll have to pass through a storm front

to get there.

to get there.

Ladies and gentlemen, please return to your seats

and fasten your seat belts.

and fasten your seat belts.

There was lightning, a lot of lightning,

There was lightning, a lot of lightning,

and the turbulence started to intensify.

Check it out, Camilo.

It's building all around the island.

It's building all around the island.

With less than 20 minutes to go,

weather at the airport is deteriorating quickly.

Get a report from San Andreas for me.

Get a report from San Andreas for me.

OK, I'll ask.

San Andres, good morning.

San Andres, good morning.

AIRES 8250.

Go ahead.

We want to know how the weather is at the airport,

please.

please.

OK, AIRES 8250, wind calm, visibility

more than 10 kilometers with scattered clouds at 1,500 feet.

more than 10 kilometers with scattered clouds at 1,500 feet.

In the cabin, passengers are getting nervous.

This shouldn't last long.

We told them that we were in an intense weather system

We told them that we were in an intense weather system

and that we would be out of it shortly.

AIRES 8250, there is now heavy rain at the airfield,

and visibility is reduced to 5 kilometers.

and visibility is reduced to 5 kilometers.

Visibility down to 5 kilometers.

Oh, man.

If visibility gets any worse,

If visibility gets any worse,

the pilots won't be able to land.

When you see particularly a weather that's deteriorating,

When you see particularly a weather that's deteriorating,

the thing that you're thinking about

is, OK, how are we gonna position the airplane

is, OK, how are we gonna position the airplane

to land in these conditions?

Landing checklist.

Speed breaks.

Speed breaks.

Armed.

Landing gear.

Down.

Moments from touchdown...

Moments from touchdown...

AIRES 8250, do you have the runway in sight?

Airfield in sight.

Runway in sight.

AIRES 8250.

500.

AIRES 8250, winds at 60 degrees at 50 knots.

AIRES 8250, winds at 60 degrees at 50 knots.

The wind has picked up.

50 knots head on.

50 knots head on.

In case of wind shear, we use maximum thrust for a go around.

Don't touch flaps or gear.

Don't touch flaps or gear.

Agreed.

Yes, sir.

Look out, Captain.

Can you make it?

Can you make it?

Climb, Captain!

We felt a hard and sudden crash.

The 737 skids more than 500 feet before

The 737 skids more than 500 feet before

finally coming to a stop.

There's been an accident.

There's been an accident.

Inside the cabin, flight

attendant Adriana Cardenas-Medina

attendant Adriana Cardenas-Medina

quickly opens the main door.

Our number-one priority was the passengers

and getting everyone to safety.

So we were all focused on that.

So we were all focused on that.

A passenger is killed in the crash.

A passenger is killed in the crash.

Another is severely injured and dies two weeks later.

Another is severely injured and dies two weeks later.

It's now up to the team of investigators

from the Colombian Aeronautical Authority

to determine the cause of the accident.

to determine the cause of the accident.

He was definitely lined up for a landing.

He was definitely lined up for a landing.

When we first looked at the debris,

we observed that the initial impact

was approximately 40 meters from the start of runway 06.

was approximately 40 meters from the start of runway 06.

What if the storm brought them down?

If the storm took the pilots by surprise,

they may have made errors in their approach.

they may have made errors in their approach.

You get very close to the airport, that's when you want

You get very close to the airport, that's when you want

to make sure that you have a good understanding

of the weather that you're about to deal

of the weather that you're about to deal

with in the final approach segment of the flight.

Can I show you this?

Can I show you this?

Investigators questioned

the air traffic controller.

Did she inform the pilots about the rapidly

Did she inform the pilots about the rapidly

changing weather conditions?

I updated them regularly once they were in my airspace.

I updated them regularly once they were in my airspace.

AIRES 8250, there is now heavy rain at the airfield,

and visibility is reduced to 5 kilometers.

and visibility is reduced to 5 kilometers.

The controllers are very good about reading

The controllers are very good about reading

up changing weather conditions, particularly

wind and visibility.

Investigators are convinced that the controllers

Investigators are convinced that the controllers

acted properly.

Something else must have doomed the pilot's final approach.

Something else must have doomed the pilot's final approach.

The team turns to the flight data recorder.

The team turns to the flight data recorder.

Look at this.

They were descending to the runway

They were descending to the runway

at 1,100 feet per minute.

The data shows the plane was descending too fast

The data shows the plane was descending too fast

and coming in too low.

Investigators have a theory why.

Investigators have a theory why.

They must have been trying to get a visual fix of the runway

as soon as possible.

By bringing the airplane down early,

By bringing the airplane down early,

the hope is that you'll see the runway earlier.

You'll be underneath the clouds and your visibility will

You'll be underneath the clouds and your visibility will

be improved the lower you get.

But for some reason, that strategy

But for some reason, that strategy

didn't work for the crew of the AIRES flight.

Investigators compare the approach

the crew should have made with the one they actually flew.

the crew should have made with the one they actually flew.

They should have stayed on the glide path.

But instead, they come in too low the entire way.

But instead, they come in too low the entire way.

Investigators are baffled by the captain's

Investigators are baffled by the captain's

actions on board Flight 8250.

Why would a person operating an aircraft

Why would a person operating an aircraft

make that type of approach?

make that type of approach?

Climb, Captain!

Colombian investigators

asked the captain of Flight 8250 about the moments

asked the captain of Flight 8250 about the moments

leading up to the crash.

It was stormy.

It must have been the lightning or the wind.

It must have been the lightning or the wind.

They never questioned the type of approach that they made.

They never doubted that their procedure was adequate.

They never doubted that their procedure was adequate.

And they said it was probably the wind

that caused their accident.

that caused their accident.

I was focused on the green lights at the threshold,

like I always do.

like I always do.

In sight landing.

Check.

We're all set for landing.

We're all set for landing.

Green lights and a series of white strips

Green lights and a series of white strips

painted on the tarmac mark the threshold

at the start of the runway.

at the start of the runway.

The thinking of some pilots has been, I want on the runway

as early as possible so that I can make sure that we get

as early as possible so that I can make sure that we get

stopped if there's a problem with the brakes.

stopped if there's a problem with the brakes.

But landing right on the threshold

leaves little room for error, especially

in stormy conditions.

in stormy conditions.

Investigators ask the captain why he did it.

That's my training.

That's my training.

I was just doing what we've always done.

The team digs further into the captain's

training and experience.

training and experience.

He's only been flying the 737 for eight months.

12 years before that, he flew turboprops.

12 years before that, he flew turboprops.

They learn Captain Gutierrez recently switched

from commanding smaller dash 8 turboprops

to the much larger 737 jets.

to the much larger 737 jets.

In turboprops, everything is much easier.

It's a slower plane.

It reacts faster.

It reacts faster.

It raises up easily.

A turboprop is very forgiving.

A jet doesn't forgive.

A jet doesn't forgive.

The captain, new to the Boeing 737,

The captain, new to the Boeing 737,

purposely tried to land it as he would a turboprop

on the runway's threshold.

on the runway's threshold.

It's risky in a jet.

But that's not enough to explain why the plane

But that's not enough to explain why the plane

crashed short of the runway.

Investigators hope the cockpit voice

Investigators hope the cockpit voice

recorder will provide the missing piece of the puzzle.

50.

Look out, Captain.

Look out, Captain.

40.

30.

Can you make it?

20.

20.

Captain!

So from the point he gets a visual of the runway,

So from the point he gets a visual of the runway,

the captain does nothing to correct his altitude

right up to the crash.

Not even when the first officer gives him warnings.

Not even when the first officer gives him warnings.

So what's going on in his head?

When the investigators looked at the flight profile

When the investigators looked at the flight profile

and they realized that it ended up impacting the ground short

and they realized that it ended up impacting the ground short

of the runway without ever really arresting itself,

the next question is, what is this consistent with?

the next question is, what is this consistent with?

You have rain causing poor visibility, some lights

You have rain causing poor visibility, some lights

on the right, very few, the runway

lights, and that's about it.

lights, and that's about it.

It's a black hole illusion.

The black hole illusion occurs on dark nights

The black hole illusion occurs on dark nights

when there are no ground lights between an airplane

and the runway threshold.

and the runway threshold.

A contrast between the lights and total darkness

creates an illusion that deceives pilots into thinking

creates an illusion that deceives pilots into thinking

the runway is closer than it actually is,

the runway is closer than it actually is,

which leads them to put the plane down too early.

It was a nighttime approach on an island

It was a nighttime approach on an island

with no noticeable difference between land and water and only

with no noticeable difference between land and water and only

the runway lights as reference.

A black hole illusion explains

A black hole illusion explains

the crash of AIRES 8250.

40.

Can you make it?

Can you make it?

That's why the crew was constantly below the flight

path without being aware of it and they

never made it to the runway.

never made it to the runway.

Following the investigation,

the Colombian Aeronautical Authority

the Colombian Aeronautical Authority

Recommends AIRES Airlines revises its procedures

for visual landings.

I think one of the most important recommendations

from this investigation was strengthening crew

from this investigation was strengthening crew

training, especially for those transitioning from turboprop

training, especially for those transitioning from turboprop

to jet.

The pilots of Flight 8250

The pilots of Flight 8250

were deceived by an illusion of the night sky.

Time and again, investigators have found that even the most

experienced pilots can get tripped up by the dark

experienced pilots can get tripped up by the dark

at a critical moment.

At Rafic Hariri International Airport in Beirut, Lebanon,

At Rafic Hariri International Airport in Beirut, Lebanon,

Captain Habtamu Negasa prepares Ethiopian Airlines

Captain Habtamu Negasa prepares Ethiopian Airlines

Flight 409 for departure.

He's been with the airline for more than 20 years.

He's been with the airline for more than 20 years.

Exterior check is complete.

Check complete, no problems.

Check complete, no problems.

First Officer Aluna Beyene

is a recent graduate of the Ethiopian Airlines Flight

Academy.

Academy.

The 82 passengers aboard the Boeing 737

The 82 passengers aboard the Boeing 737

are preparing for an overnight flight

to Addis Ababa, Ethiopia.

Clear for takeoff.

Runway 21.

Immediate right turn to Shaka.

Immediate right turn to Shaka.

Ethiopian 409.

Takeoff thrust set.

Speed increasing.

Speed increasing.

Rotate.

It's just after 2:30 in the morning.

Their takeoff procedure and the initial part

of the takeoff seemed entirely routine

of the takeoff seemed entirely routine

and ordinary and well-executed.

Heading select.

Heading select.

Heading select, check.

Ethiopian 409, good morning.

Climb flight level, 290.

Climb flight level, 290.

Flight level 290, Ethiopian 409.

Flight level 290, Ethiopian 409.

Weather ahead is now a problem.

If there's lightning in the area, you see the flashes.

You're beginning to feel turbulence.

You're beginning to feel turbulence.

Sir, I suggest that due to the weather,

you follow heading 270 to be in the clear.

you follow heading 270 to be in the clear.

21, say again.

Confirm heading 210.

Confirm heading 210.

Suddenly, the situation in the cockpit

turns critical.

The airplane is being banked beyond

The airplane is being banked beyond

its normal operational limits.

its normal operational limits.

Captain Negasa attempts

to correct the problem by turning the plane back

toward the thunderstorm.

toward the thunderstorm.

Ethiopian 409, follow heading 270.

Ethiopian 409, follow heading 270.

Turn right heading 270.

Turn right heading 270.

OK, what heading did he say?

270.

Set.

Set.

What is it?

What is it?

Speak.

What is it?

Go around, go around.

Go around, go around.

Bank angle.

Bank angle.

Thrash it.

Go around.

Ethiopian 409, follow heading 270, sir.

Follow heading 270.

Turn right heading 270 now.

Turn right heading 270 now.

Whenever a controller tells the pilot to do something now,

Whenever a controller tells the pilot to do something now,

the controller is telling the flight that they're

in immediate danger.

Flight 409 is in jeopardy shortly

after taking off from Beirut.

Ethiopian 409, you are going into the mountain.

Ethiopian 409, you are going into the mountain.

Turn right now heading 270.

He was worried that the crew was

He was worried that the crew was

going to fly the airplane into the hills

behind Beirut airport.

But the aircraft doesn't get that far.

The 737 plunges from the sky...

The 737 plunges from the sky...

Oh, God!

Oh, God!

Oh, God!

...into the Mediterranean Sea.

Ships in the area are alerted.

And Lebanon's Civil Aviation Authority

dispatches investigators.

So we want to answer very important questions to the

So we want to answer very important questions to the

family, why my relative died.

It's soon apparent there are no survivors.

It's soon apparent there are no survivors.

Most of the plane is lying at the bottom of the sea.

Without more wreckage, investigators

Without more wreckage, investigators

may never discover what brought down Flight 409.

may never discover what brought down Flight 409.

Because the 737 is American-made,

the National Transportation Safety Board's Dennis Jones

the National Transportation Safety Board's Dennis Jones

joins the team.

We're out there, but it looks like it's... it's coming along.

We're out there, but it looks like it's... it's coming along.

We still didn't have a crash site, per se.

The flight recorder, which is always

a big concern of interest, was still yet to be found.

a big concern of interest, was still yet to be found.

Get the flight track from Harare International.

Desperate for clues, investigators

piece together the plane's flight path.

piece together the plane's flight path.

When we first got there, some of the information

we had that was helpful was the radar data.

we had that was helpful was the radar data.

It paints a confusing picture.

It's like no one's flying.

It's like no one's flying.

Exactly.

After takeoff, the plane follows

an unusual, erratic course.

an unusual, erratic course.

You would wonder what...

what really what happening, as if there

what really what happening, as if there

were no crew in the cockpit.

The investigation is at a standstill

The investigation is at a standstill

when it gets a major boost.

Let's get that out.

Let's get that out.

The flight recorders are recovered.

Ah, yeah.

That's it.

They may reveal why the plane

They may reveal why the plane

was flown so erratically.

Exterior checks complete.

The team listens to the cockpit voice recorder

The team listens to the cockpit voice recorder

for any sign of trouble.

We want to try to get a better understanding

if there might have been some kind of mechanical problem.

The takeoff sounds completely normal.

The takeoff sounds completely normal.

Rotate.

Then investigators hear the controller

give the pilots a new heading.

give the pilots a new heading.

But that's not the direction the plane flies.

As they approached the heading that they had been assigned,

they overshot the heading.

they overshot the heading.

They're way off course.

Sir, I suggest that due to the weather,

you follow heading 270 to be in the clear.

you follow heading 270 to be in the clear.

Each time the pilots try to correct their course,

they turn too far and bank too steeply.

they turn too far and bank too steeply.

Ethiopian 409, you are going into the mountain.

Ethiopian 409, you are going into the mountain.

Turn right now heading 270.

The airplane was rolling into an ever steeper bank,

The airplane was rolling into an ever steeper bank,

The airplane was rolling into an ever steeper bank,

ultimately leading to a spiral.

The plane was out of control.

The plane was out of control.

Nothing on the recording

indicates a mechanical failure.

It was just something that we certainly

It was just something that we certainly

didn't have any answers for in the beginning.

Investigators scour the cockpit recording

for clues they may have missed.

Exterior checks complete.

Exterior checks complete.

Check complete, no problems.

They noticed something odd.

They noticed something odd.

During the takeoff roll...

Do you see that?

...the captain saw something because he tells his first

...the captain saw something because he tells his first

officer, did you see that?

But then there was no reaction from the first officer.

But then there was no reaction from the first officer.

The first officer is silent.

The first officer is silent.

OK, engage the autopilot.

Hold on.

Stop for a second.

That would have changed things.

The advantage of engaging the autopilot in that situation

The advantage of engaging the autopilot in that situation

is that the pilot can then let the autopilot worry

about the attitude of the airplane

about the attitude of the airplane

while he sits back and takes the big picture,

maintains situational awareness.

maintains situational awareness.

But the autopilot was never turned on.

Nor was there a reply to the captain's order.

Nor was there a reply to the captain's order.

Had the autopilot been engaged when the captain ordered

Had the autopilot been engaged when the captain ordered

the first pilot to engage it, it would

have saved the whole flight.

have saved the whole flight.

Investigators need to find out why the first officer

failed to act.

failed to act.

Investigators now know the first officer of Flight 409

didn't turn on the autopilot when the captain

didn't turn on the autopilot when the captain

commanded him to do so.

OK.

But the recording also reveals

some questionable behavior on the part of the captain.

He never noticed that the autopilot wasn't engaged.

What is it?

What is it?

Bank angle.

It forces investigators to consider

an unlikely explanation of what else went wrong,

an unlikely explanation of what else went wrong,

something called subtle incapacitation.

If the pilot at the control has a stroke and slumps

If the pilot at the control has a stroke and slumps

over the control wheel, there's no question that you've got

a person who's incapacitated.

a person who's incapacitated.

However, if the pilot at the controls

starts to lose the picture, and does so silently,

starts to lose the picture, and does so silently,

and starts to misapply controls or push the wrong buttons,

and starts to misapply controls or push the wrong buttons,

it may take a while before the other crew members

it may take a while before the other crew members

pick up on that failure.

That sequence is called subtle incapacitation.

That sequence is called subtle incapacitation.

Bank angle.

Bank angle.

Bank angle.

Bank angle.

It's a dynamic that goes

beyond the usual definition of pilot error.

What is it?

What is it?

Subtle incapacitation can come from physiological reasons,

psychological reasons, or a combination of both.

psychological reasons, or a combination of both.

It could be something minor.

Medications could cause it.

Medications could cause it.

Stress could cause it.

Fatigue could cause it.

Investigators scrutinize the cockpit

recording for more information.

recording for more information.

What are these guys doing?

They listen to the crew's conversation

just before takeoff.

just before takeoff.

This room doesn't make you sleepy?

If you hear someone on the recorder saying "sleep,"

immediately our antennas stick up.

What was in that food we had?

What are they doing up there?

What are they doing up there?

The team hears the crew

discussing symptoms of fatigue.

All right.

Did you feel dizzy?

Did you feel dizzy?

Oh, I... I couldn't sleep.

Well, me too.

Investigators question why the pilots were so tired.

Investigators question why the pilots were so tired.

Employment records reveal that the captain worked almost

Employment records reveal that the captain worked almost

non-stop for nearly two months.

non-stop for nearly two months.

That supports the theory of subtle incapacitation.

Sir, I suggest that due to the weather,

Sir, I suggest that due to the weather,

you follow heading 270 to be in the clear.

21, say again.

21, say again.

Fatigued and under increasing stress,

the pilots become disoriented in the dark.

the pilots become disoriented in the dark.

Bank angle.

Bank angle.

Bank angle.

It seems that the crew was never fully

on top of what was happening.

Go around, go around, go around!

Go around, go around, go around!

Roger, go around.

Roger, go around.

Investigators conclude that the accident was caused

Investigators conclude that the accident was caused

by a crew that was too tired to properly

recover from a wrong turn.

They recommend Ethiopian Airlines

introduce rigorous new rules regarding flight crew rest.

introduce rigorous new rules regarding flight crew rest.

It's one thing to have the experience and the expertise

to do the work, but you have to be in good condition

to do the work, but you have to be in good condition

in order to perform.

When a flight crew is lost in the dark,

When a flight crew is lost in the dark,

they may have just seconds to regain their bearings.

Because when they don't, the result can be fatal.

Because when they don't, the result can be fatal.

33,000 feet above the Arctic, a Bombardier CRJ-200 jet

33,000 feet above the Arctic, a Bombardier CRJ-200 jet

is on a late-night mail run for one of Sweden's largest cargo

companies, West Air Sweden.

companies, West Air Sweden.

We are approaching Bodo, where the outside air temperature

is a balmy -61 Celsius.

is a balmy -61 Celsius.

Fuel?

The 42-year-old Spanish captain has

more than 3,300 flying hours.

more than 3,300 flying hours.

Holding at -30.

We are good.

We are good.

His French first officer

is 33, with a similar number of flying hours.

is 33, with a similar number of flying hours.

They're on a 90-minute flight from Oslo

to Tromso, a remote community north of the Arctic Circle.

to Tromso, a remote community north of the Arctic Circle.

Ready for the approach briefing?

Ready for the approach briefing?

Let's do it.

ILS approach to runway 01.

Inbound heading 009.

50 feet.

50 feet.

The plane is due to land

in Tromso in about 30 minutes.

And according to us at Atas, we can

And according to us at Atas, we can

expect light wind and zero...

what the hell?

what the hell?

The captain suddenly notices

that his plane is climbing.

that his plane is climbing.

What?

But just as quickly, it's in a dive.

Come up!

Come up!

Come up!

Come up!

Bank angle.

- Ah! - Come on, help me.

Bank angle.

Help me.

Help me.

Yes, I'm trying, I'm trying.

Yes, I'm trying, I'm trying.

Turn left.

Turn left!

The pilots can no longer

make sense of what's happening.

Bank angle.

Bank angle.

Mayday!

Mayday!

Mayday!

Mayday!

Mayday!

Mayday!

Flight 294 speeds toward the ground

at more than 450 miles an hour.

at more than 450 miles an hour.

We need to climb.

Come on, we need to climb.

Come on, we need to climb.

Yes, yes, we need to climb.

Turn left, turn left.

No, continue right.

Bank angle.

Continue right.

OK, dammit.

Come on, help me.

Help me, please!

I don't know.

I don't see anything.

Bank angle.

- Bank angle. - No!

- Bank angle. - No!

No!

No!

The plane slams into the ground

at close to 600 miles an hour.

at close to 600 miles an hour.

It takes rescue helicopters three hours

to find the crash site.

The information we got from the rescue efforts

The information we got from the rescue efforts

was that the accident was most probably not at all survivable.

was that the accident was most probably not at all survivable.

The next day, a team from Sweden's Accident

Investigation Authority, known as the SHK,

Investigation Authority, known as the SHK,

arrives at the crash site.

They find a crater 20 feet deep.

They find a crater 20 feet deep.

They definitely came in hard and fast.

That's not normal.

You probably don't have a lot of control

You probably don't have a lot of control

over the aircraft at that time.

The position of the wreckage and the size

The position of the wreckage and the size

of the crater suggests the plane hit the ground at very

high speed and upside down.

high speed and upside down.

The question facing the SHK is how Flight

294 came to such a tragic end.

294 came to such a tragic end.

Incredibly, both of the plane's black boxes

have survived the crash.

have survived the crash.

Investigators hope the flight data

will help reveal the cause.

will help reveal the cause.

So they're cruising at 33,000 feet

when suddenly, they start to pitch way up.

when suddenly, they start to pitch way up.

A plane normally changes pitch

by about 1 degree per second.

by about 1 degree per second.

But in this case, you had 6 degrees per second.

So it was a really rapid change of pitch.

So it was a really rapid change of pitch.

Then the plane starts pitching down

and starts rolling out of control.

and starts rolling out of control.

We could see this is not normal.

We could see this is not normal.

But wait a minute.

If the plane is pitching up, why is the altitude decreasing?

If the plane is pitching up, why is the altitude decreasing?

That can't be right.

When a plane pitches up,

it should also gain altitude and slow down.

But the data indicates that's not what Flight 294 did.

But the data indicates that's not what Flight 294 did.

His airspeed indicator was not changing.

His airspeed indicator was not changing.

Same with the altitude.

The altitude should have showed a climb.

The altitude should have showed a climb.

That can't be what the plane was doing.

The plane's pitch data makes no sense.

The plane's pitch data makes no sense.

We made calculations to determine the real pitch of

We made calculations to determine the real pitch of

the aircraft during the event.

The calculations point to something astounding.

The calculations point to something astounding.

So no pitch up at all?

So no pitch up at all?

Not that we can tell.

What the hell?

It seems the captain thought

It seems the captain thought

the plane was pitching up when it actually

was still flying level.

If they aren't actually pitching up,

If they aren't actually pitching up,

why are they pushing the nose down?

Data on the plane's pitch

comes from what's called an inertial reference

comes from what's called an inertial reference

unit, or IRU.

It's made up of gyroscopes that provide

It's made up of gyroscopes that provide

information to both the cockpit displays

and the flight data recorder.

There are two IRUs, one for each pilot's display.

There are two IRUs, one for each pilot's display.

The FDR gets its data from the captain's side, IRU.

The FDR gets its data from the captain's side, IRU.

Now this is what the captain was seeing.

Now this is what the captain was seeing.

The captain's instrument was telling him

The captain's instrument was telling him

that the plane was pitching up, even though it was flying level

that the plane was pitching up, even though it was flying level

and that it was rolling to the right

when it was actually in a left roll.

when it was actually in a left roll.

What the hell?

It's now clear the captain

was receiving bad information from a faulty IRU.

was receiving bad information from a faulty IRU.

So what then was the first officer seeing?

So what then was the first officer seeing?

Investigators turned to the cockpit voice recorder.

All right, let's see what they say.

All right, let's see what they say.

They listen for anything that

might reveal what the first officer's

pitch display was telling him.

pitch display was telling him.

We need to climb.

Come on, we need to climb.

Yes, we need to climb.

Go left, go left.

Go left, go left.

Bank angle.

Bank angle.

Continue right.

OK, dammit.

OK, dammit.

Bank angle.

The bank angle warning is

fed data from the IRU designated to the first officer's side.

fed data from the IRU designated to the first officer's side.

Bank angle.

The presence of that warning

tells investigators that his IRU was working properly.

tells investigators that his IRU was working properly.

Bank angle.

Come on, help me.

Help me, please.

I don't know.

I don't see anything.

I don't see anything.

Inertial reference unit number 2 was working as it should be.

The first officer was getting good information.

The first officer was getting good information.

The discovery confirms the first officer

should have known the plane wasn't pitching up.

should have known the plane wasn't pitching up.

So why did he let the captain fly the plane into the ground?

So why did he let the captain fly the plane into the ground?

What the hell?

When the captain of Flight 294

mistakenly put his plane into a nosedive,

mistakenly put his plane into a nosedive,

the first officer should have identified the problem

when he looked at his display.

when he looked at his display.

So why didn't he intervene?

So why didn't he intervene?

As the team digs deeper into the FDR data...

Come up!

Come up!

...they make an important discovery.

Mayday! Mayday!

Mayday!

Both pilots receive what's

called a miscompare warning.

The warning is shown on both displays

The warning is shown on both displays

when there's an inconsistent reading between them.

In this case, PIT for pitch.

In this case, PIT for pitch.

The flight data reveals that both pilots

got the pitch discrepancy warning,

got the pitch discrepancy warning,

yet took no action to address it.

It's a puzzling find.

Investigators need to understand exactly

what the pilots experienced when their instruments began

what the pilots experienced when their instruments began

to fail.

They book time in a CRJ flight simulator.

They book time in a CRJ flight simulator.

OK, so let's start the error on the left side, please.

OK, so let's start the error on the left side, please.

They program a fault into the IRU

on the captain's side.

on the captain's side.

When the captain's faulty display shows a sudden climb,

When the captain's faulty display shows a sudden climb,

the miscompare warning comes on, informing

the flight crew that they are receiving

different pitch readings.

different pitch readings.

OK.

All right, let's pick it up here.

And now we've got the declutter mode kicking in.

Freeze it there, please.

Freeze it there, please.

When a pilot's display reaches extreme pitch

or roll values, it goes into something

or roll values, it goes into something

called declutter mode.

All non-essential information disappears.

All non-essential information disappears.

And guess what disappears in declutter mode?

The PIT discrepancy warning

The PIT discrepancy warning

alerting the pilots of mismatched displays

also vanishes.

Four seconds after that warning appeared,

Four seconds after that warning appeared,

it disappears for good.

Not enough time for the captain to detect it.

Not enough time for the captain to detect it.

What the hell?

He instinctively pushes the nose

He instinctively pushes the nose

down, not realizing he's actually

putting the plane into a dive.

The first officer's gauge also goes into declutter mode,

The first officer's gauge also goes into declutter mode,

but accurately shows the opposite configuration of

the captain's faulty display.

the captain's faulty display.

Come up.

Now, neither one of them has a discrepancy warning.

Now, neither one of them has a discrepancy warning.

As the pilot struggled to regain control...

As the pilot struggled to regain control...

Turn left.

Turn left!

...both miss a vital piece of information,

...both miss a vital piece of information,

that their displays are showing different pitch angles.

That's one bit of information that really

That's one bit of information that really

should not have been removed when it goes

to a decluttering function.

The team now has a detailed picture of what

The team now has a detailed picture of what

happened in the cockpit.

We need to climb.

Come on, we need to climb.

Come on, we need to climb.

Yes, yes, we need to climb. Turn left.

Turn left!

No, continue right.

But even though the cruise instruments failed them,

But even though the cruise instruments failed them,

there might have been a way to escape catastrophe.

Even when flying at nighttime, there can still be visual cues

Even when flying at nighttime, there can still be visual cues

that can help you understand the orientation of your aircraft,

things like you can still see a visible horizon sometimes when

things like you can still see a visible horizon sometimes when

there are a lot of city lights.

Investigators now want to know what the pilots could

Investigators now want to know what the pilots could

see that night.

To do that, they take to the skies in an identical plane

To do that, they take to the skies in an identical plane

on the same route and under the same conditions

as on the night of the accident.

as on the night of the accident.

And I can just see the horizon over there.

And I can just see the horizon over there.

At first, the test reveals

nothing out of the ordinary.

OK, let's start the descent into Tromso.

OK, let's start the descent into Tromso.

Now I can't see anything out there.

Now I can't see anything out there.

It was very difficult to discern

the horizon during this flight when you had

the horizon during this flight when you had

the cockpit illumination on.

It's the breakthrough investigators need.

It's the breakthrough investigators need.

With the cockpit lights turned on,

it would have been impossible for the pilots

it would have been impossible for the pilots

to see the lights below, much less the horizon.

The pilots on Flight 294 would have depended entirely on

their instruments for guidance.

their instruments for guidance.

But those instruments contradicted each other.

When we can't see outside, we trust our instruments.

When we can't see outside, we trust our instruments.

But if your instrument is telling you something that

is completely separate from what your body is telling you,

is completely separate from what your body is telling you,

it's not a matter of ignoring one or the other.

It's a matter of verifying what the situation is.

It's a matter of verifying what the situation is.

The discovery reveals the last critical piece

of the puzzle.

of the puzzle.

Ready for the approach briefing?

Let's do it.

Shortly after the captain of Flight

294 switches on the cockpit lights...

294 switches on the cockpit lights...

According to Los Atus...

...his display shows the plane suddenly pitching up.

...his display shows the plane suddenly pitching up.

What the hell?

But the glare inside the cockpit means the pilot

But the glare inside the cockpit means the pilot

cannot see the horizon.

The captain can't tell that the plane is actually flying level.

The captain can't tell that the plane is actually flying level.

Had this happened earlier when they might have had some form

of a visible horizon, it could have had

of a visible horizon, it could have had

an entirely different outcome.

In less than 30 seconds,

the plane is upside down and diving.

the plane is upside down and diving.

Bank angle.

Investigators believe that rapid fire chain of events

Investigators believe that rapid fire chain of events

triggers what's known as startle or surprise effect

in both pilots.

in both pilots.

That surprise effect, together with the lack of communication

That surprise effect, together with the lack of communication

between the pilots, can explain the difficulties there

were to solve the problem.

were to solve the problem.

Bank angle.

Upside down and hurtling to the ground,

the first officer's display shows

the first officer's display shows

what the plane is actually doing, diving and banking left.

Come up.

Bank angle.

Bank angle.

But the captain sees the opposite, a plane

climbing and rolling right.

Come up.

Come up.

His first officer's plea to climb makes no sense.

Come on, help me.

Yes, I'm trying, I'm trying.

Yes, I'm trying, I'm trying.

Turn left.

Turn left!

It's an induced reality.

Then it begins to get confusing.

Then it begins to get confusing.

And if you get past a certain point,

that confusion can become terminal.

The captain's faulty IRU was

recovered from the crash site.

But it's too damaged to reveal the cause of the malfunction.

But it's too damaged to reveal the cause of the malfunction.

In their final report, investigators

list the faulty IRU and the pilots ensuing failure

list the faulty IRU and the pilots ensuing failure

to communicate among the main factors causing the accident.

to communicate among the main factors causing the accident.

It's important to communicate really early when you've

It's important to communicate really early when you've

got a problem so the other pilot can understand what's going on.

got a problem so the other pilot can understand what's going on.

Three deadly crashes are triggered

when pilots fly blind.

Only training, experience, and teamwork

Only training, experience, and teamwork

can prevent disaster when the view from the cockpit

goes dark.

goes dark.

We are dealing in a hostile environment up there,

and when push comes to shove, we need to know what our body's

and when push comes to shove, we need to know what our body's

response is, our mental response, our eyes and brain

and what they're going to tell us.

Without that, we're gambling.

Without that, we're gambling.