Original subtitles

Co-Pilot: 1,000 feet and climbing.

Narrator: A brand new 737

takes off during an intense storm.

Controller: They should be there by now.

Narrator: And then mysteriously falls from the sky

over West Africa.

[Screaming]

Man: Those who operate these type of aircraft,

they had the same question.

What happened? What happened in Cameroon?

Narrator: Investigators scour the crash site for clues.

Investigator: It hit the ground over there.

Man: This was the toughest accident scene

I've been on in my career.

Investigator: But look at this.

Narrator: When the investigators review the flight data...

Pilot: Allah!

Automation: Bank angle.

Pilot: We're crashing!

Narrator: They discover there was an inexplicable fight

For control in the cockpit.

Co-Pilot: Left! Left!

Left correction!

Investigator: Who flies like that?

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!

Narrator: In Douala, Cameroon,

Kenya Airways Flight 507 is almost an hour behind schedule.

Andrew Kiuru: Ladies and gentlemen,

we are going to wait

for the weather conditions to improve before we take off.

Narrator: A severe storm must pass

Before the pilots can depart.

There are 108 impatient passengers on board.

Many need to catch connecting flights.

Flight 507 began in Abidjan earlier in the day.

It's now bound for Nairobi, Kenya.

Tom Kok: 507 was a very common flight for Kenya Airways.

Particularly the last decade, the amount of traffic

from East Africa to West Africa has really increased,

partially because there's much more business going on.

[Thunder]

Narrator: The Boeing 737-NG,

recently acquired by Kenya Airways,

is the newest generation of twin-engine commercial jets.

Kok: This was a new era of aviation in Africa

where airlines, and particularly the bigger ones,

invest in brand new aircraft.

[Thunder]

Narrator: Captain Francis Wamwea is in command

of tonight's flight.

He's an experienced pilot with more than 8,000 hours

in the cockpit.

Andrew Kiuru is his first officer.

The young pilot joined Kenya Airways a year ago.

Francis Wamwea: Let's see what this storm is doing.

Narrator: The pilots use the 737's onboard weather radar

to monitor the storm.

Wamwea: It looks like there might be a way around it.

Narrator: Now that the storm has moved off the end of the runway,

Captain Wamwea believes he can fly past it.

Kok: It's quite common that the weather may be a factor in delay

in Africa because of its severity,

so it's not, in that respect, a surprise for the operator

to find this kind of weather at that time of the night.

Wamwea: Tower, Kenya 507.

It looks like there's a break in the weather.

Requesting startup.

Controller: Okay, 507. Startup approved.

Wamwea: Startup checklist. Quickly, please.

Kiuru: Uh, generators on.

Narrator: A few minutes before midnight,

Flight 507 is finally ready for takeoff.

Wamwea: Okay.

Request taxi clearance.

Kiuru: Kenya 507, requesting taxi clearance.

Controller: Taxi runway 12, Kenya 507.

Kiuru: Taxi runway 1-2, Kenya 507.

♪

Wamwea: Put on the wipers.

Kiuru: Right is clear.

Narrator: The crew taxis to the runway.

There's one flight ahead of them,

Royal Air Maroc flight 287.

Pilot: Royal Air Maroc 287, in position, runway 1-2.

Latest weather, please.

Controller: Visibility 800 meters.

Wind calm.

Rain, moderate thunderstorms.

Wamwea: Alright.

Controller: 287, cleared for takeoff.

Narrator: The Royal Air Maroc flight departs without incident.

Wamwea: Wait till we line up.

Kiuru: Okay.

Usually things happen quickly, though.

Wamwea: Huh. Okay.

Try to keep up.

Narrator: Captain Wamwea double checks the storm's position.

Wamwea: Let's have a look.

Narrator: And confirms the route around the lingering storm cell.

Wamwea: Tower, Kenya 507.

After departure, we would like to maintain a heading

slightly left of runway, due to weather ahead.

Kiuru: Right!

Wamwea: Ah. Sorry. Slightly right.

Kok: Just after the aircraft took off,

the plan was to make a small turn to the right

to avoid the most active weather cells

that they saw on the weather radar in front of them.

Controller: Approved.

Wamwea: Okay.

All done.

Kiuru: Ladies and gentlemen, a kind reminder

to ensure your seatbelts are well fastened for takeoff.

Cabin crew to your seats.

Okay, takeoff thrust is set, speed building on both.

Wamwea: Check.

Kiuru: 80 knots.

Wamwea: Check.

Kiuru: V-1. Rotate.

Narrator: Just after midnight,

Kenya Airways Flight 507 finally departs for Nairobi.

Wamwea: Gear up.

Kiuru: Okay.

♪

1,000 feet and climbing.

Wamwea: Heading select.

Kiuru: Selected, check.

Narrator: The 737 starts turning right to avoid the storm.

Kiuru: N-1. Wamwea: Okay, command.

Kiuru: So, should I remain on this heading?

Wamwea: Yep.

Kiuru: 2,400 feet and climbing.

Wamwea: Now we're getting into it.

♪

ALLAH!

[Alarm Beeping]

Automation: Bank angle. Bank angle.

Narrator: Suddenly, the 737 rolls dangerously to the right.

Wamwea: Allah!

Automation: Bank angle. Bank angle. Bank angle.

Narrator: The captain fights to level the plane.

Automation: Bank angle. Bank angle.

Narrator: But it continues banking

further and further right.

♪

[Beeping]

Automation: Bank angle. Bank angle.

Narrator: Despite the pilots' efforts, they keep rolling.

[Alarm Beeping]

Wamwea: We're crashing!

Kiuru: Yeah, we are crashing!

Left! Left!

Left correction!

Automation: Terrain. Terrain. Bank angle. Pull up. Pull up.

[Screaming]

Narrator: Five hours later,

the controller in Douala is ending his shift.

[Phone Rings]

Controller: Douala tower.

No reason I can think of.

They should be there by now.

Narrator: Kenya Airways flight 507 should have landed

in Nairobi 45 minutes ago, but the plane has still not arrived.

Controller: Sure.

Narrator: And no one even knows where to start looking for it.

Kenya Airways flight 507 was due in Nairobi

at 6:15 a.m. local time.

But it never arrived.

By morning, news of the missing 737 has spread.

Families and friends of the passengers want to know

where their loved ones are.

Engelbert Zoa-Etundi worked for

Cameroon's Civil Aviation Authority.

[Speaking French]

Engelbert Zoa-Etundi [Translated]: When I first heard

that an aircraft was missing, I immediately thought

we were going to have a catastrophe on our hands.

Narrator: Two days later, search teams finally locate

the wreckage of Kenya 507.

It's three and a half miles southeast of Douala Airport.

The 737 has crashed into a mangrove swamp

and is submerged in mud and water.

There are no survivors.

Mwai Kibaki: As a nation, we are united in grief.

Narrator: It's a tragic turn of events.

Victims' friends and family are demanding answers

from the Cameroonian government.

But the government has a problem.

Zoa-Etundi: Cameroon did not have an agency

in charge of air accident investigations.

Narrator: Investigators from several countries

Descend on Cameroon.

Since the Boeing 737 is manufactured

in the United States,

Dennis Jones from the U.S.

National Transportation Safety Board,

the NTSB, joins the investigation.

Dennis Jones: The fact that it was a relatively new airplane

at the time certainly made it a little bit more compelling,

but all around the world,

those who operate these type of aircraft,

they had the same question.

What happened? What happened in Cameroon?

Investigator: It's all from the tail.

Jones: Looks like everything else is down in there.

I saw a lot of debris from the tail section.

We were not able to see the wreckage itself,

because the particular, we were in a swamp.

And that was another challenge throughout the whole process.

Narrator: A technical advisor for Boeing, Mark Smith,

also joins the team of investigators.

Mark Smith: This was the toughest accident scene

I've been on in my career at Boeing.

We're standing there looking around at the devastation,

the destruction.

So we have to, as a team, start working on what happened to it,

where are the various pieces.

Narrator: A key piece of evidence is quickly found,

the 737's flight data recorder.

Jones: Well, it looks pretty good, considering.

Narrator: The FDR is sent

to Canada's transportation safety board to be downloaded.

While searchers continue looking for the cockpit voice recorder,

investigators try to determine what caused the plane to crash

so soon after takeoff.

Investigator: The airport is only

three and a half miles away.

They can't have been in the air more than two minutes.

Smith: We really didn't have a clue.

Jones: You're looking for explanations.

We were able to start doing

A lot of on-scene examination, documentation

to try to get an idea how it impacted the ground.

Narrator: The layout of the wreckage tells investigators

how the plane was flying on impact.

Jones: Completely obliterated.

Investigator: We still haven't found the most of it.

Jones: It looks like it came in hard and fast.

When you have a high-speed impact like that

and a nose-down attitude,

you usually get extensive fragmentation of the aircraft.

Smith: Actually what we're trying to do is estimate,

if we can, an angle and maybe even a speed of impact

to try and get a feel for what happened,

'cause, once again, we don't yet have the FDR data.

Jones: How deep does this go?

Investigator: More than 15 feet.

Jones: Well, it definitely hit nose-first, and hard.

So, was there some kind of loss of control that took place?

That was what was kind of foremost on my mind.

Narrator: While they wait for the flight data,

Investigators turn to the controller

on duty that night to help fill in some blanks.

Investigator: What can you tell me about that night?

Controller: The first thing

is that they delayed their takeoff.

Investigator: Really? How come?

Controller: There was a storm coming in from the east.

[Thunder]

Kiuru: Tower, 507. [Sighs]

We are going to wait for this storm to pass.

Cancelling startup.

Controller: Roger 507, cancelling startup.

The storm could last all night, but visibility should improve.

Smith: The airplane was on the tarmac loaded, ready to go,

waiting for the weather to clear and then they would take off.

Investigator: But 20 minutes later they decide to take off.

Why?

Controller: It cleared a bit,

and they were going to try to get around it.

Wamwea: Tower, Kenya 507.

It looks like there's a break in the weather.

Requesting startup.

Controller: Okay, 507. Startup approved.

Narrator: The controller explains how the crew planned

to fly to the right of the storm.

Is it possible the crew misjudged

the storm's size and strength?

NTSB investigator Bill Bramble also joins the team.

Bill Bramble: They had a cell

eight miles off the end of the runway,

so the crew was using their own radar

to decide how to maneuver around the cell.

Investigator: Here's the meteorological report

from that night.

Jones: Thunderstorm and rain over the airport

with winds gusting up to 20 knots.

But it was starting to clear.

Narrator: Investigators wonder if the wind and rain

were still severe enough to bring down a 737.

Investigator: He asked permission from the controller

to go around the storm.

To the right.

Jones: Maybe the storm was worse than he thought.

There was a weather delay for several flights.

KQ-507 was one of four flights that were delayed on the ground

for about an hour.

Narrator: Investigators need to speak to other pilots

who took off from Douala that night.

How intense was the storm once they were in the air?

Investigator: I will speak to one of the pilots tomorrow.

Narrator: Investigators interview a pilot

who departed immediately after Kenya Airways Flight 507.

Investigator: No problems at all? Not even mild turbulence?

Narrator: They need to find out

if he had any difficulty avoiding the storm.

Smith: The flight crews solely depended

on their own onboard systems

to understand what they were getting into.

There was no assistance from the ATC.

Investigator: So, no problems at all?

Not even mild turbulence?

Jones: He said that the weather was smooth after they took off.

They did the same thing, too.

They took off and turned to the right, too,

to circumnavigate the weather.

Investigator: Okay. Thank you for your time.

Narrator: Investigators conclude the pilots could have maneuvered

around the storm on their flight path.

With weather ruled out,

the team wonders if there was a mechanical issue

with the brand new 737.

Bramble: This was important,

because it was the first for the 800 series,

and if there's an accident and it's not immediately understood

what the problem is,

it's really important to get to the bottom of it.

Narrator: Technicians in Canada have been able

to extract the FDR data.

Investigator: Let's see what we've got.

Smith: They read the data out.

Altitude, air speed, bank angle,

pitch attitude, those sorts of things.

Once you plot those out, you can start seeing what occurred.

Narrator: Any malfunction warnings during the flight

would provide an important clue.

Jones: There might have been some kind of mechanical issue

that might have popped up.

No warnings.

Narrator: They find no signs of any system failure.

Smith: The data showed us the airplane was behaving

as we would expect it to.

It was a perfectly airworthy aircraft.

There's no question about it.

Narrator: As the team continues looking through the data...

Investigator: But look at this.

Narrator: They discover that just over a minute

into the flight, a different kind of alert did go off.

Jones: Bank angle alert at an altitude of 2,800 feet.

Narrator: For investigators, this is their first real clue

about what happened to flight 507.

Any roll exceeding 35 degrees is considered extreme.

Once reaching that angle, a warning alerts pilots of danger.

Automation: Bank angle.

Kiuru: Rotate.

Narrator: When investigators review the pilot's inputs

after takeoff, they make a critical discovery.

Wamwea: Gear up.

Kiuru: Okay.

Jones: He was turning left from the moment they left the ground.

That information showed us that right after takeoff,

the aircraft started to roll to the right a little bit

and the pilot corrected it.

And then he keeps making corrections to the left.

Investigator: It looks like he's trying to keep the plane level.

Narrator: But what caused the slow roll to the right

in the first place?

Jones: Bingo!

It's the way the flaps were rigged.

Gave it a slight right roll.

The aircraft had a tendency to roll to the right.

Narrator: The flaps increase a plane's lift at slower speeds.

On this particular airplane,

the left flap provided slightly more lift than the right one.

Smith: It's similar to driving down the freeway in your car

and just letting go of the wheel.

If I was to do that,

then it'll start to drift off one way or another.

That's the way the airplane was slowly and naturally banking.

Narrator: This discovery explains why the captain

kept his control column turned to the left

immediately after takeoff.

Jones: Well, that's weird.

Narrator: But it doesn't explain

an even more puzzling element of the flight data.

Jones: Look at this.

The captain's control wheel inputs seem to stop.

It's like he just let go of it.

Six degrees right, he does nothing.

11 degrees, 15 degrees, 20 degrees,

30 degrees, and still nothing.

Narrator: As the plane's bank angle approached 35 degrees,

neither pilot took action

to stop the increasingly dangerous roll.

[Alarm Beeping]

Automation: Bank angle. Bank angle.

Kiuru: Allah!

Narrator: Until the bank angle warning sounded.

Automation: Bank angle. Bank angle.

Jones: And then he does this:

right, left, right again, left again.

-[Beeping] -Automation: Bank angle.

Zoa-Etundi: In the last moments of the flight,

we noticed an erratic movement of the control column

that didn't make any sense.

Automation: Bank angle. Bank angle.

Narrator: For 16 seconds after the bank angle warning,

the aircraft continued its dangerous roll.

Smith: The airplane just continues to roll right

up to 110 degrees of bank.

The crew didn't recover it before impact.

Automation: Bank angle. Bank angle.

Narrator: The data paints a baffling picture

of the one-and-a-half-minute flight.

Investigator: Who flies like that?

Smith: And that was puzzling to us.

So it really highlighted that we needed more information,

we needed more data.

And that data is the CVR.

The CVR is what tells us the conversation,

what might they have been looking at.

Narrator: But after weeks of searching the crash site,

there's still no sign of the cockpit voice recorder.

It's been more than a month

since the crash of Kenya Airways Flight 507,

and the cockpit voice recorder has still not been found.

Jones: Over there.

Smith: We spent days scouring the site, up track, down track,

everywhere, looking for the CVR, trying to find it.

[Beeping]

Narrator: The team now uses a tracking device

to scan the swamp for a signal from the box.

[Beeping]

[Beeping Quickens]

Five weeks after the crash,

the cockpit voice recorder is finally recovered.

Jones: That was a very, very exciting time for everyone

involved with the recovery,

as well as the investigation group itself,

for having that information.

Jones: Okay, let's start on the ground.

Investigator: Start it.

Narrator: Investigators hope the recording will explain why

the pilots let their plane bank so dangerously to the right.

Wamwea: Tower, Kenya 507.

Looks like there's a break in the weather.

Requesting startup.

Controller: Okay, 507. Startup approved.

Wamwea: Okay. Request taxi clearance.

Narrator: They hope the recording will also explain

how they ended up spiraling into a swamp.

Kiuru: 1,000 feet and climbing.

Wamwea: Heading select.

Jones: Okay. This is where he stops making any inputs.

Kiuru: Selected. Check.

N-1.

Wamwea: Okay, command.

Jones: That's the call to activate the autopilot.

Kiuru: So, should I remain on this heading?

Wamwea: Yep.

Narrator: After calling for the autopilot to be engaged,

Captain Wamwea released the control column,

trusting the autopilot to fly the plane.

But there's a problem.

Jones: The autopilot didn't come on.

Investigator: He thought the 737 was flying itself.

Smith: There was nobody flying the controls,

so nothing was controlling the airplane.

Narrator: The discovery changes the course

of the entire investigation.

Kiuru: N-1.

Wamwea: Okay, command.

Narrator: Why didn't the autopilot come on?

Investigator: The captain calls for the autopilot to be engaged,

but the first officer does not respond.

Smith: The procedure should be for the first officer

to push the button and say, "the autopilot engaged."

Wamwea: Okay, command.

Kiuru: So, should I remain on this heading?

Wamwea: Yep.

Narrator: Investigators believe the first officer was so focused

on inputting the route around the storm

that he failed to engage the autopilot.

Kiuru: 2,400 feet and climbing.

Wamwea: Now we're getting into it.

Narrator: Meanwhile, the captain assumed the autopilot

was engaged and controlling the pre-selected right turn.

Wamwea: Allah!

[Alarm Beeping]

Automation: Bank angle. Bank angle.

Narrator: The pilots only noticed a problem

When the bank angle warning went off.

Automation: Bank angle. Bank angle.

Smith: It's pretty clear the captain expected the autopilot

to be engaged, and it didn't get engaged.

And then neither crewmember picked up the fact

that it wasn't engaged.

Wamwea: We're crashing!

Kiuru: Yeah, we are crashing!

Left! Left! Left correction!

[Screaming]

Narrator: Why did neither crewmember

take the critical step of engaging the autopilot?

Bramble: Standard operating procedures

provide a safety net for crews,

but if crews don't adhere to the standard operating procedures,

they lose that protection.

Narrator: They comb through Kenya Airways procedures

to see who has the responsibility

for activating the autopilot.

Investigator: Anything?

Jones: From what I can tell,

it's not really clear who was supposed to do it.

All it specifies is

"Turn on when above minimum altitude for engagement."

That's not very helpful.

It wasn't really clear in the standard operating procedures

of when the autopilot does come on,

who's responsible for doing it,

and what the response should be to that.

Wamwea: Allah!

Automation: Bank angle. Bank angle.

Narrator: Recovering from a 35-degree bank

is not a complicated procedure.

[Beeping] Automation: Bank angle. Bank angle.

Narrator: The bank angle warning is designed

to give pilots enough time to react,

but for some reason this crew wasn't able to do that.

The team digs into their records.

Investigator: This is what we have on Wamwea.

Jones: Lots of experience.

16 years as a pilot, most of those on a 737.

Wamwea: Let's see what this storm is doing.

Bramble: The captain had been a flight attendant

for Kenya Airways years and years ago,

and then went to flight school and got his ratings

and transitioned into the role of pilot.

Investigator: Wait. Look at this.

Narrator: But the captain's training records

reveal serious shortcomings.

Jones: Inadequate knowledge of systems and procedures.

Insufficient flight discipline.

Poor cockpit scans.

Below standard.

Yikes.

Wamwea: Gear up.

Kiuru: Okay.

Bramble: We discovered the captain had a history

of training difficulties and lack of systems knowledge

for auto-flight systems and so forth,

so he had some red flags in his history.

Jones: The first officer's report isn't any better.

Investigator: Failed to monitor autopilot when engaged.

Kiuru: V-1. Rotate.

Bramble: The first officer was young and fairly inexperienced.

He only had a little over 800 hours of flight time,

and he had had some training feedback that involved things

like you need to be more proactive

about calling out deviations and so forth.

Jones: Not an A-level crew.

Wamwea: We're crashing!

Kiuru: Left correction!

[Beeping] Automation: Bank angle. Bank angle.

Narrator: Did a lack of skills in the cockpit

doom the 108 passengers on board the flight?

[Screaming]

Wamwea: Allah!

[Beeping] Automation: Bank angle. Bank angle.

Narrator: Investigators need to determine if pilot error

caused the horrific crash of Kenya Airways Flight 507.

[Crash]

Jones: Okay.

"Allah."

He's definitely surprised.

Then 22 degrees to the right.

20 left.

45 right, then 11 to the left.

That's not helping.

[Beeping] Automation: Bank angle. Bank angle.

Jones: When the bank warning came on

and the aircraft was in a right roll,

the first response was the captain turned it

further to the right, which aggravated the situation.

Now the bank angle is approaching 50 degrees.

Smith: As the situation grew worse,

after the bank angle warning and the confusion amongst the crew,

the autopilot does engage and the captain pushed that button.

Automation: Bank angle. Bank angle.

Narrator: The team discovers that when the captain finally

realized the autopilot was not engaged, he activated it.

Automation: Bank angle.

[Beeping] Bank angle. Bank angle.

Narrator: But when it didn't immediately level the plane,

the captain turned the control column erratically,

an action which overrode the autopilot.

Wamwea: We're crashing!

Kiuru: Yeah, we are crashing!

Investigator: Then "Yes, we are crashing.

Left, left. Left correction."

Jones: So now one's trying to turn left

while the other turns to the right.

They're fighting each other's inputs.

Kiuru: Left! Left!

Left correction!

[Beeping] Automation: Bank angle. Bank angle.

[Crash]

Jones: I don't get it.

It should have been a simple recovery.

The back and forth was trying to do corrective actions,

but it didn't seem like it was correcting anything.

Smith: He's already banked over to the right 34 or 35 degrees.

Why would he roll further?

Well, that's the question we have to answer right there.

Narrator: Investigators use a Boeing simulator

to recreate the final stages of the flight.

Jones: From the simulator, you can literally put yourself

in the driver's seat and reconstruct the flight

and be there as the pilot to be able to determine

whether you can recover.

Can we give it a 50-degree right bank, please?

Activate the autopilot, please.

Pilot: Exactly what it's supposed to do.

The roll is slowing.

Jones: And the inputs we discussed.

Pilot: Right, left, right.

Jeez. There goes the autopilot.

Bank angle's increasing again.

[Beeping] Automation: Bank angle. Bank angle.

Narrator: The simulation shows that if the captain

had given the autopilot enough time to take control,

the 737 would have returned to a relatively safe bank angle.

But his erratic inputs prevented that from happening.

Jones: If only he'd done nothing.

Smith: It was determined that recovery was still an option

just, just a few seconds before impact, really.

Narrator: Investigators are puzzled.

Why wasn't the experienced captain able to execute

such a straightforward recovery?

Smith: Was there something here that we were missing

in the investigation that may have confused the crew?

So we started looking harder

at the possibility of spatial disorientation.

Investigator: From the simulator?

Jones: Yeah.

Investigator: Just darkness outside.

No reference at all.

Smith: It was a completely black view out the windshield.

If you look up out the windshield,

you have no ground reference that could immediately

have helped you straighten the airplane out.

Wamwea: Allah!

Automation: Bank angle. Bank angle.

Narrator: Spatial disorientation is an inability to distinguish

up from down, left from right.

Automation: Bank angle.

Narrator: It has been known to hinder judgment

and delay response times.

Automation: Bank angle. Bank angle.

Wamwea: We're crashing!

Kiuru: Yeah, we are crashing!

Left! Left!

Left correction!

Narrator: Only the first officer seemed to assess

the situation correctly.

Kiuru: What! What are you doing?

Automation: Bank angle.

Jones: The first thing he says is, "Yeah, we are crashing."

It took him 10 seconds to speak up.

[Beeping] Automation: Bank angle. Bank angle.

[Beeping] Bank angle. Bank angle.

Bramble: When the bank angle alert went off,

There wasn't much discussion about what was happening

until the captain said...

Wamwea: We're crashing!

Bramble: We're crashing.

Kiuru: Yeah, we are crashing!

Bramble: And the first officer didn't say anything

until he said that.

Kiuru: Left correction!

Narrator: The team listens to the recording

of the first leg of the flight from Abidjan to Douala.

They are looking for clues

as to why the first officer remained silent.

Jones: Let's hear it.

Wamwea: What is wrong with you?

Narrator: What they hear shocks them.

When investigators listen to the cockpit voice recording

of the first leg of Kenya Airways Flight 507...

Kiuru: Sorry, did you say an altitude of 14,000 feet?

Wamwea: Yes! Don't be so stupid.

Write it down if you can't remember.

Jones: Wow.

Narrator: They're stunned by

how the captain treated his first officer.

Bramble: It was pretty bad.

The captain was sort of browbeating the first officer.

There were words like "stupid," "shut up," stuff like that

that you wouldn't expect to hear

in a professional crew environment.

Wamwea: What is wrong with you?

Did you not hear the instruction?

Heading 2-3-0!

Understand?

Bramble: The first officer seemed to kind of shut down.

Wamwea: Heading 2-3-0! Understand?

Bramble: He was at a certain point sort of reduced

to responding with these sort of monosyllabic grunts.

[Beeping] Automation: Bank angle. Bank angle.

Narrator: Investigators suspect this might explain

why the first officer took so long to speak up.

Automation: Bank angle. Bank angle.

Bramble: The captain's behavior toward the first officer

on the first flight likely caused him to adopt

sort of a passive role.

You need both pilots actively engaged in checking each other

and catching errors, and if one pilot adopts a passive role,

they're gonna be less effective.

Investigator: So, heightened ego?

Narrator: Captain Wamwea's treatment of his first officer

leads investigators to examine

his professional history more closely.

Investigator: Can you tell me, tell me more information?

Jones: We spent a lot of time going through pilot records,

interviewing other flight crewmembers.

Were there any...?

Narrator: They quickly learn the captain's shortcomings

were not limited to his flying abilities.

Bramble: He had a lot of concerning things

in his training files about being overbearing,

being authoritarian in terms

of how he dealt with other crewmembers.

Investigator: So, we have a young, reserved first officer

and an overbearing captain.

Bramble: This accident is kind of a throwback

to those early days where we were focused on the issues

of overly assertive, authoritarian,

overbearing captains,

and submissive, inadequately assertive junior first officers.

Jones: A lethal combination.

Narrator: Investigators conclude the bad pairing

in this flight crew

set in motion a sequence of events that led to the crash.

Smith: As an investigator, all of these accidents I've worked,

it's very clear there is never a single cause.

It's always a chain of events.

Kiuru: So should I remain on this heading?

Wamwea: Yep.

Narrator: A deadly combination of poor pilot performance

and spatial disorientation contributed to the accident.

Wamwea: Now we're getting into it.

Bramble: All the risk factors were present.

There was distraction,

there was reduced outside visibility,

and there was confusion.

Narrator: But in the end, investigators conclude

that one major mistake triggered the entire tragedy.

Kiuru: N-1.

Wamwea: Okay, command.

Kiuru: So, should I remain on this heading?

Wamwea: Yep.

Narrator: It was the crew's failure

to ensure the autopilot was turned on...

Wamwea: Allah!

Automation: Bank angle. Bank angle.

[Screaming]

Narrator:...that ultimately led to the deaths of 114 people.

Wamwea: We're crashing!

[Alarm Beeping]

[Crash]

Narrator: In the aftermath of flight 507's crash,

Cameroon's commission of inquiry

Makes a series of recommendations,

including the regular update of safety manuals

related to cockpit procedure and crew responsibility,

and improved pilot training.

Jones: They made changes to the standard operating procedures

about who's responsible for engaging the autopilot.

And that was very key.

Narrator: With a focus on upset recovery.

Automation: Bank angle. Bank angle.

Bramble: One technology that Boeing has tested and developed

and is looking at putting into its airplanes

is a roll recovery arrow,

so that if you're at an unusual angle of bank,

the attitude display will actually show you

which direction you need to roll the airplane

and provide an accompanying aural.

Smith: In the end, you have to look at training,

crew makeup, all adding into all the links of chain,

the chain that caused this to happen this night.

Wamwea: Let's see what this storm is doing.

Jones: And those who are not familiar

with accident investigation

think that all the answers are at the crash site.

It's rarely at the crash site.

And that's exactly what happened.

Kiuru: Rotate.