All language subtitles for Air.Disasters.S18E06.Whos.in.Control.1080p.SMIT.WEB-DL.AAC2.0.H.264-maldini_track3_[eng]

[jet engine]

FLIGHT ATTENDANT:
Ladies and gentlemen,

we're beginning our descent
towards Amsterdam's Schiphol

Airport.

[non-english speech]

Thank you.

NARRATOR: Turkish
Airlines Flight 1951 is

preparing to land in Amsterdam.

Amsterdam, Turkish 1951,
descending to 7,000, speed 250.

[beeping]

NARRATOR: The crew is flying
a state of the art Boeing 737.

Flaps 15.

PILOT: Localizer are live.

Localizer capture.

NARRATOR: In the final
moments of the flight,

the landing turns
into a catastrophe.

The plane falls like a rock.

The crash of Turkish
Airlines Flight 1951

involves the most
popular plane on Earth.

With nearly 1 and 1/2 million
passengers boarding 737 sevens

every day--

[screaming]

--investigators
need to figure out

if the problem
was with the plane

or with the pilots flying it.

FLIGHT ATTENDANT:
Ladies and gentlemen,

we are starting our approach.

PILOT: We lost both engines.

FLIGHT ATTENDANT: [inaudible]
emergency descent.

PILOT: Mayday, mayday.

CHILD: We're going to die.

[explosion]

PILOT: This will
be the last one.

REPORTER: The investigation
started when [inaudible]..

MAN: It's going to crash.

[somber music playing]

NARRATOR: On the morning
of February 25, 2009,

Turkish Airlines Flight
1951 becomes the first plane

to crash at Amsterdam's Schiphol
Airport in more than 10 years.

[non-english speech]

INTERPRETER: It smashed
into the ground really hard.

It made a tremendous noise.

[crash]

NARRATOR: The plane hits
the ground in a muddy field

just North of Runway 18 Right.

[sirens]

Since the crash was so
close to the airport,

rescue workers arrived quickly.

Most of the passengers
have survived.

But many are badly injured.

Survivors are taken
straight to local hospitals.

Images of the Amsterdam
accident quickly

spread around the world.

This is the third
crash of a passenger

jet in the past six weeks.

The sudden nature of this
accident adds to the mystery.

[inaudible speech over radio]

It doesn't take long for
the Dutch Safety Board

to arrive at the scene.

They will be investigating
this accident.

But they won't be alone.

The crash involved an
American-made plane.

So the US National
Transportation Safety Board

sends Joe Sedor, one of its
most experienced investigators,

to Amsterdam.

JOSEPH SEDOR: When it's a
non-US registered aircraft that

crashes overseas, such
as this Turkish Airlines,

we are the state of manufacture
and design of the air frame

and also, in this
case, the engines.

Fuselage in three large pieces.

Engines forward of
the main wreck site.

NARRATOR: Flight 1951
was one of the most

advanced aircraft in the skies,
The Boeing 737 800 Series.

It's designed to travel longer
routes at higher altitudes.

The new generation 737 is
still the best airplane Boeing

ever built. We developed an
airplane that had an improved

wing, improved avionics,
simpler systems

that required less maintenance.

NARRATOR: Investigators know
this isn't just any plane.

The 737 is the world's
best-selling commercial jet.

Finding out why this one
crashed is imperative.

There are more than 5,000
of them in the skies.

They carry about 1 and 1/2
million passengers a day.

Investigators must
quickly determine

if there's a flaw
with the plane that

could cause another accident.

What they know so
far is that flight

1951 had been traveling from
Istanbul, Turkey to Amsterdam.

There were 128 passengers on
board the early-morning flight,

including four
engineers from Boeing.

FLIGHT ATTENDANT:
Ladies and gentlemen,

we're beginning our descent
towards Amsterdam's Schiphol

Airport.

Please raised your seat
backs to the upright position

and stow away your tray tables.

NARRATOR: There was no
mention on board of any kind

of trouble in the cockpit.

The crash has killed
nine people, including

three members of the Boeing team
and the pilots in the cockpit.

See if you can get me some
aerials of the crash site.

NARRATOR: There are
eerie similarities

to another recent accident
involving a Boeing aircraft,

British Airways Flight 38.

JOSEPH SEDOR: Approximately
a year before this,

there had been Triple
Seven short landing

at Heathrow, which had
a dual-engine flame out.

NARRATOR: In that accident,
a Boeing Triple Seven

fell to the ground,
short of the runway.

The British Airways
pilots reported

that both their engines
stopped delivering

power just before landing.

At the time of the
Turkish Airways crash,

the cause of that accident
hasn't been found.

As in that case,
investigators have

plenty of clues to work with.

The plane and its engines
are largely intact.

The flight-data recorder
and cockpit voice recorder

are found in good condition.

There are also
plenty of survivors

to describe what happened.

According to the passengers,
the landing had been routine.

But then suddenly, the plane
simply dropped out of the sky

and hit the ground.

[crash]

But perhaps the
biggest clue comes

from the crash site itself.

The wreckage is not spread out.

It tells investigators
that the plane could not

have been traveling
forward at high speed

when it hit the ground.

JOHN NANCE: The way the
aircraft had crashed,

it did appear to be some
sort of a landing accident

in which there was moderate
control of some sort.

NARRATOR: The pattern of
debris and the passenger

reports point investigators
to an immediate suspect,

the engines.

The engines issue was a very
big issue in my thought process

at the time, initially.

NARRATOR: There's no evidence
of fire on the fuselage.

In many crashes, fuel
in the plane's tanks

ignites on impact.

The lack of fire raises
an obvious question.

Did the engine stop
running because flight

1951 had simply run out of gas?

JOHN NANCE: That was one of the
first thoughts that I had was,

did this airplane
have fuel aboard?

Because otherwise,
how does a 737

literally fall out of the sky
on approach to an airport?

NARRATOR: But the
location and condition

of the plane's engines
suggest that perhaps

they didn't quit in flight.

JOSEPH SEDOR: Sure it
looks like it was running.

When we first looked at
where the engines ended up,

the initial impression was that
they probably were producing

thrust at impact, given
that they were so far

forward of the main wreckage.

But that was just a
very general conclusion.

NARRATOR: Only the flight-data
recorder can tell investigators

how much power the engines
were generating in the seconds

before the crash.

It had lots of fuel.

Rules that out.

NARRATOR: It doesn't
take long to discover

that there is plenty of
fuel in the plane's tanks.

Flight 1951 definitely
did not run out of gas.

Passengers report that in the
final seconds before the crash,

the plane hit what
felt like turbulence.

It points investigators
to a well-known culprit,

a micro burst.

A micro burst is a
powerful column of air that

shoots out of storm clouds.

It can literally slam a
low-flying plane to the ground.

JOHN NANCE: If an airplane flies
into that at approach speeds,

you're not going to
be flying anymore.

You're going to
come out of the sky.

Certainly, it was one of
the things that all of us

took a look at,
at the beginning,

was there a micro burst?

[crash]

NARRATOR: In 1985, a
Delta Airlines flight

was caught in a micro
burst while landing

at Dallas-Fort Worth Airport.

The plane hit the ground
short of the runway.

137 people were killed.

Investigators learned
that there were

heavy clouds above the airport
at the time of the accident.

A powerful gust of wind may
well have accompanied them.

The flight-data recorder
will have recorded

wind speeds outside the plane.

Investigators will
need to analyze

the flight data to prove
the micro-burst theory.

In the meantime, the rescue has
led to an unusual discovery.

JOSEPH SEDOR: There was
three pilots in the cockpit

which is unusual.

This is a two-crew cockpit.

So why was that
third pilot there?

NARRATOR: Since none
of the three pilots

survived the accident,
it's all the more

urgent for investigators
to retrieve

the data from the
cockpit voice recorder.

It records conversations
in the cockpit.

They're in luck.

JOSEPH SEDOR: Because of the
way that the aircraft crashed,

access to the recorders and
the condition of the recorders

was excellent.

NARRATOR: The reason for the
third pilot is soon uncovered.

Flying standard arrival route.

Visibility, 3,500
meters, expected

to decrease to 2,500 meters.

NARRATOR: For first
officer, Murat Sezer

this has been a training
flight of sorts.

He was new to the
airlines and was

being shown the intricacies of
landing at Amsterdam's airport.

BILL HUFF: When the
Jeppesen charts,

which is what all pilots use to
navigate to and from Schiphol,

there's 102 pages of
information on Schiphol alone.

So there's dozens of approaches.

Runway 18 right has three
high-speed exits to the left.

NARRATOR: The captain, Hasan
Arisen was doing double duty.

He was training
his first officer--

Make small corrections as
we get close to the runway.

NARRATOR: --and was in
command of flight 1951.

It's because captain Arisen
was teaching that there was

the third pilot in the cockpit.

Olgay Ozgur was a safety pilot.

He was there to keep an eye
on the flight's progress

during this training mission.

JOSEPH SEDOR: The purpose
of that second set of eyes

is to make sure that the
captain and the first officer,

if they're in a
situation where it's

a little bit of a training
portion of the flight,

that they don't miss something.

We've got a clean recording?

NARRATOR: The voice recorder
reveals that the three crew

members began
preparations for landing

when still above 8,500 feet.

Amsterdam, Turkish
1951, descending to 7,000.

Speed, 250.

[beeping]

NARRATOR: But the voice
recorder has picked up

an unusual sound, a
warning that makes no sense

at this stage of the flight.

One of the
investigators from Boeing

was a engineering pilot that
came and helped with the CVR.

And he's listening to see when--

are there any unusual
sounds that can be

heard that would not be normal.

AIR TRAFFIC CONTROLLER
(OVER RADIO):

Speed OK for ILS 18 Right.

PILOT: Descend
4,000, ILS 18 Right.

NARRATOR: The alarm
keeps sounding.

It's the
landing-gear-configuration

warning horn.

Captain Arisen
continually dismisses it.

Turkish 1951, dissent
4,000, ILS 18 Right.

Landing gear.

Is that the
landing-gear warning?

They're 8,300 feet here.

NARRATOR: The warning
is a solid clue.

But investigators can't
yet see how it could

possibly have caused a crash.

got warnings to extend their
landing gear while still

thousands of feet in the air.

JOSEPH SEDOR: On
the initial listen,

we heard a gear
warning horn occur

as the aircraft was approaching,
when it was still up.

And it was coming in at
about 10,000 feet and below.

NARRATOR: Investigators now
turn to the flight-data recorder

to help solve some
of the mystery

surrounding this flight.

The analysis of wind
speeds outside the aircraft

is completed.

It's clear.

None are drastic enough to
have brought down the plane.

There's no evidence
of a micro burst.

NARRATOR: But the
flight-data recorder

does provide some valuable
insight into the cause

of the landing-gear warning.

One of the instruments
that measures altitude

had the plane already
on the ground.

JOSEPH SEDOR: When
we looked and saw

the radio altimeter
data on the recorder,

it said about 8,000 feet.

And then immediately, it
went down to about minus 8.

Minus 8 feet is an indication
that the aircraft's

on the ground.

But of course, it's
still at 2000 feet.

NARRATOR: The Boeing
737 is equipped

with two separate altimeters.

One measures air pressure
to determine the plane's

height above sea level.

That reading is displayed
prominently in the cockpit

on both pilots' flight display.

PILOT: 210, sensor.

NARRATOR: The plane is
also equipped with a radio

altimeter.

It's made up of four antennas.

Two transmit signals to
the ground and two others

read the signal that
bounces back to determine

the plane's altitude.

It's precise.

It's very, very precise.

Pressure altimeters can
sometimes be not as accurate.

And radar altimeters
are 100% accurate

if they're working properly.

[jet engine]

NARRATOR: One antenna
feeds the reading

to the first officer's display.

The other feeds the
captain's instruments.

In the case of Flight
1951, the captain's side

was wrong most of the flight.

Investigators go
back over the CVR

and make a puzzling discovery.

PILOT (OVER RADIO):
Amsterdam Turkish 1951

descending to 7,000, speed 250.

Radio altimeter.

NARRATOR: Captain Arisen
seems to have known

that the landing-gear
warning was being caused

by a faulty radio altimeter.

The airplane thought that
it was low to the ground

and the gear was not down.

And the captain recognized
that the problem was really

in the radio altimeter,
showing him that they

should be on the ground.

And he goes, it's just
the radio altimeter.

NARRATOR: Throughout
much of the approach,

the captain's radio
altimeter had been displaying

a reading of minus
8 feet, triggering

the warning to lower the gear.

They treated it like
it was a nuisance.

AIR TRAFFIC CONTROLLER
(OVER RADIO):

Turkish 1951, descend to 2,000.

2,000, 1,951.

NARRATOR: Investigators dig
for any other abnormalities.

They learn that with Flight
1951 a little over 10 miles

from the airport,
controllers directed

the pilots to begin
their final turn

to line up with the runway.

Turkish 1951, left heading.

210, cleared approach.

18 right.

Left 210, clear
ILS, Turkish 1951.

COPILOT: 210 set, Sir.

NARRATOR: This turn
puts Flight 1951 in line

with Runway 18 Right.

It's equipped with an instrument
landing system which sends

out a signal, outlining
the ideal descent

path to the foot of the runway.

The autopilot follows
that glide path

until the plane is a few
hundred feet from the ground.

Then the pilot takes over.

It makes landing
almost effortless.

The ILS is pretty
easy to follow.

It's a video game.

NARRATOR: The crew begins
configuring their plane

for landing, unfazed
by the warning

horn that's repeatedly triggered
by the malfunctioning radio

altimeter.

Flaps 15.

NARRATOR: Six miles
out, Flight 1951

picks up the ILS
signal that will

guide the plane to the runway.

Localizer are live.

Localizer capture.

NARRATOR: The safety
pilot, Olgay Ozgur,

now reminds captain Arisen
about the failed altimeter.

We have radio
altimeter failure, Sir.

OK.

AIR TRAFFIC CONTROLLER
(OVER RADIO):

Turkish 1951, Runway 18
Right, clear to land.

Cleared to land.

Thank you.

NARRATOR: Investigators
are stumped.

The crew knew about
the malfunction

and continued their approach.

How had it then
caused them to crash?

Clearly, there was
more to this accident

than a faulty altimeter.

JOHN NANCE: The whole premise
of airline safety, the way

we build the airplanes,
the way we fly them,

is based on the idea that we
can have any number of failures

and we should still be
able to arrive safely.

The radio altimeter is
just one instrument.

There's no way in the world
that that one instrument, if it

fails, should be a
major cause of worry

that we're going
to have a crash.

NARRATOR: Investigators
wonder if the crew

had been given proper
guidance for their approach.

They turn to exchanges
between the pilots

and the controller
who guided them in.

They carefully review
every instruction.

AIR TRAFFIC CONTROLLER
(OVER RADIO): Turkish 1951,

send to 4,000.

Speed OK for ILS 18 Right.

Turkish 1951, descend to 2,000.

Turkish 1951, left heading,
210, cleared approach.

18 Right.

NARRATOR: By following the
controller's instructions,

the crew made their final turn
much too close to the runway.

So they intercept properly,
they should be here.

NARRATOR: International
guidelines call for approaching

planes to intercept the signal
that guides them to the runway

from below.

It's so pilots
don't have to make

any drastic, last-minute course
corrections to get to it.

To intercept here,
they had to descend.

NARRATOR: But flight 1951 was
given instructions that brought

it to the threshold of the glide
slope while still way above it.

It's a common
practice at Schiphol

because it gets planes
to the runway faster.

JOSEPH SEDOR: Because
they were so close,

they had to capture the
glide slope from above.

Although it is an
unusual situation,

it is one that that can be
handled by a flight crew

if it is managed properly.

NARRATOR: Approaching a
glide slope from above

is more difficult, mostly
because the crew has

to suddenly slow the
plane and descend rapidly

to intercept the signal.

BILL HUFF: We also call
this a slam-dunk approach.

And some pilots like it.

Some pilots don't.

It's a little bit harder.

And things happen quicker when
you're above the glide path,

trying to intercept from above.

And it's just a challenge
for a lot of pilots.

NARRATOR: The
approach from above

increased the crew's workload.

But it's standard practice
at Schiphol airport.

I've flown in to skip
over dozens of times.

And I expect it.

NARRATOR: If the
controller's instructions

had somehow overtaxed this
crew, their conversations

would indicate it.

They're just three
miles from the runway.

PILOT: 1,000.

Check.

PILOT: Flaps, 40.

Speed brake?

COPILOT: Speed brake armed.

Green light.

One thing at a time.

Landing gear?

COPILOT: Gear down.

Three green.

PILOT: Flaps?

Flaps 40.

Green light.

PILOT: 500.

All lights on.

Please warn the cabin crew.

Cabin crew, take your seats.

[beeping]

NARRATOR: Then, real
trouble, a stall warning.

COPILOT: Speed, Sir.

I have control.

100 knots of speed.

NARRATOR: Arisen fought
to save his plane.

But just 400 feet above
the ground and less than a

mile from the runway,
the Boeing 737

suddenly fell straight down.

It only took a few seconds
for it to hit the ground.

[muffled screams]

[crash]

NARRATOR: The CVR
recording sheds

light on the final minutes of
Turkish Airlines Flight 1951.

The crew was configuring
their plane for landing well

after it should have been done.

Flaps 40.

Green light.

NARRATOR: Most airlines
have regulations that

call for a flight
to be stabilized,

to have all checklists
completed by the time

the plane hits 1,000 feet.

In instrument conditions, you
required a 1,000 feet to have,

basically, everything done.

The airplane is configured.

You have slowed.

You have run your
before-landing check.

And you have received
your landing clearance.

And from 1,000 feet on in, you
just monitor the instruments

and were looking for the runway.

Please warn the cabin crew.

Cabin crew--

NARRATOR: In fact, this crew was
still running their checklist

up to the moment the crisis
hit, 460 feet above the ground.

This approach
was not stabilized.

JOSEPH SEDOR: And because
the aircraft was unstable,

the flight crew was in a very
high-workload environment in

the last 1,000 feet of flight.

NARRATOR: The radio
altimeter was malfunctioning.

The aircraft was
giving off warnings.

The crew was assigned
a challenging approach.

And they were executing
a checklist late.

But none of this explains
why Flight 1951 crashed.

In these type of
accidents, you can never get

inside the head of the pilots.

And that's a very
frustrating type of accident.

NARRATOR: But the flight-data
recorder does provide

another intriguing clue.

Moments before Flight 1951 hit
the ground, the plane's engines

were at idle, hardly
providing any power.

Perhaps this
accident is a repeat

of the Heathrow incident.

JOSEPH SEDOR: The engines,
it was interesting to note,

were at idle approximately the
last two minutes of flight,

until the very end, when the
thrust was increased again.

That was a big red
flag right there.

The question is is,
why was that the case?

NARRATOR: But then
they spot something

that's very different from
the accident at Heathrow.

Retard-flare mode.

NARRATOR: For some reason,
while still more than 1,000 feet

above the ground,
the plane's computer

began preparing to touch down.

In retard-flare mode,
engine power is reduced

to idle by the flight computer.

And the plane's nose
automatically pitches up

to the flare position.

Planes should only be
in this configuration

just before they
touch the ground.

The autopilot raises the
nose to break the descent.

The auto throttles brings the
power back to flight idle.

And you touch down
with the power

either all the way in idle
or just about to be in idle.

NARRATOR: But Flight 1951 went
into a slow, nose-up position

well before touchdown,
causing the plane

to fly slower and slower
throughout its descent.

Speed, Sir.

NARRATOR: So why was Flight
1951 in landing mode?

COPILOT: [inaudible]
loss of speed.

NARRATOR: And why hadn't any
of the three crew members

noticed how slowly
they were flying?

[crash]

[screaming]

So what else was going on
when the engines went to idle?

NARRATOR: The trouble seems to
start with the malfunctioning

altimeter.

JOSEPH SEDOR: We had to look
at the system as a whole

and to see how that minus 8
affected the other systems

on the aircraft.

And that was a very big
portion of this investigation.

We had to say, how did the
autopilot use that data?

More importantly, how did the
auto throttle use that data?

NARRATOR: The
computer that flies

the plane consists of two
main systems, the autopilot

and the auto throttle.

The auto throttle determines how
much power to ask the engines

for while the autopilot
controls the plane's

altitude and direction.

The two systems
work independently

of each other and only one
of the radio altimeters

provides information
to the auto throttle.

In this case, I had to
learn everything there was

about radio altimeters
and auto throttle systems,

which I didn't know before.

NARRATOR: The
pieces of the puzzle

begin coming together
when they find

the connection between
the faulty radio

altimeter and engine power.

The radio altimeter
provides information

to the auto throttle
from the captain's side.

NARRATOR: The only altimeter
feeding information to the auto

throttle was the captain's.

And it was wrong.

It showed minus 8
feet throughout most

of Flight 1951's approach.

It's beginning to look
like the faulty radio

altimeter triggered the
events that led to the crash.

Investigators need to know
what went wrong with it.

On a 737, the transmitting
and receiving antennas

for both radio
altimeters are lined up

underneath the cockpit.

Three of the antennas were all
but destroyed in the crash.

They can't be tested.

But one antenna from the
captain's side is undamaged.

Investigators consider two
possibilities, a failure of one

of the components or
some sort of interference

that caused the faulty reading.

The only component that
survived the crash checks out.

The computers that control
the system also work.

But investigators do make a
curious discovery about them.

They aren't the same
ones that were installed

on the plane when it was
delivered to Turkish Airlines

seven years ago.

This find changes the
focus of the investigation.

JOSEPH SEDOR: The
maintenance aspect

of this accident aircraft
was one that we looked

at as deeply as we could.

NARRATOR: When the plane's
maintenance log is studied,

investigators find that the
radio altimeter on this plane

had a problematic history.

JOSEPH SEDOR: We got additional
data from Turkish airlines.

And that data showed that, on
this one aircraft, of the past,

I believe, over
1,000 flights, there

was about 150 flights that had
faulty radio-altimeter systems.

NARRATOR: The documents show
that a little more than a year

before the crash,
both computers were

replaced because
of complaints they

were causing faulty readings.

One of the incidents involved
a radio-altimeter reading

of minus 8 feet.

[beeping]

JOSEPH SEDOR: So that was
telling us that there was

an issue that had been there.

The issue did not just
occur on this flight.

NARRATOR: The faulty
readings persisted.

Mechanics repeatedly
swap the computers

and replace the antennas to
try to solve the problem.

It's determined that Turkish
Airlines tried several ways

to fix the altimeter.

But they couldn't find
a repair that worked.

At the time of the
accident, Turkish airlines

had a fleet of 52 Boeing
737 800-series airplanes.

JOSEPH SEDOR: It's on page 93.

When we reviewed the
maintenance data,

we found that radio-altimeter
problems had been

written up several times
on both the Axon airplane

and the fleet.

NARRATOR: Investigators
discover that in the year

before the crash,
Turkish Airlines

dealt with 235 system
faults with the radio

altimeters on their 737s.

Fixes ranged from Replacing and
exchanging antennas, cleaning

of the systems, exchanging
and replacing the computers,

and installing gaskets
to shield the system

from possible water damage.

It's not like they weren't
doing anything about it.

JOSEPH SEDOR: The Turkish
Airlines maintenance personnel

knew that the
radio-altimeter problem

was one of their highest issues
with regard to maintenance.

NARRATOR: 16 of those
altimeter repairs

were made to the plane that
crashed in February, 2009.

If the problem
was so widespread,

investigators wonder why it
hadn't caused serious problems

before this accident.

They don't have to
dig too far back

to find out that, in fact, it
had, on this very same plane.

On two recent flights, they
had the exact same problem.

NARRATOR: Twice, in the 48 hours
leading up to the accident,

the radio altimeter
showed a negative reading,

putting the plane into
retard-flare mode.

Both times, the crew
noticed the problem,

disengaged the auto throttles,
and brought the plane

in for a safe landing.

You just disconnect
it and fly the airplane.

NARRATOR: In the
months after the crash,

other operators came forward
with similar stories.

In Australia, in
the Netherlands,

in Canada, in Austria,
pilots report their 737s

going into retard-flare mode
when the left radio altimeter

showed a faulty reading.

Each of those crews
reacted the same way.

They disengaged the
auto throttle and pushed

the power back up manually.

They all landed safely.

BILL HUFF: Things are going
to break on an airplane.

And usually, you're able
to identify that and take

that out of-- make
it so that it's

not a threat for the landing.

NARRATOR: In 2008,
Boeing received

a whopping 2,569 reports
of faulty radio altimeters

on their latest 737s.

But very few of those
cases involve the plane

going into retard-flare mode.

Hardly any reports at all.

NARRATOR: Boeing also
tried, but couldn't

find the cause of the failures.

They concluded that the
radio-altimeter problem was not

a threat to safety
because the 737 gives

off enough warnings
so that crews

can intervene and land safely.

In fact, in every instance where
the radio altimeter failed,

crews were able to recover.

Turkish Airlines Flight 1951
seems to be the one exception.

Investigators still
don't know why.

It really got us
wondering of what happened.

And that's when we started
to look really closely

at the actions of
the flight crews

while it was on
that final approach,

in less than 1,000 feet.

of Turkish Airlines Flight
1951, the circumstances

of the tragedy become clear.

They see a remarkable sequence
of events that transpire

to bring down this plane.

So what was happening
when the plane

went into retard-flare mode?

NARRATOR: They discover that
the plane went into landing mode

and pulled back power at
the worst possible moment,

exactly as the
crew was descending

to meet the glide slope.

It masked what was
actually happening.

NARRATOR: As the crew configured
their plane to drop down

to meet the glide slope, they
expected the plane to slow

down as part of that maneuver.

But the plane was
actually slowing down

because the computer
was in landing mode.

That's why none of
the three pilots

said anything about the
throttles moving to idle.

BILL HUFF: It was insidious.

Where it first captured
in the retard mode,

it didn't hurt them at all
because they were actually high

and they were a little bit fast.

And the pilots actually
wanted the power back anyway.

In fact, the throttles
may have already

been in the flight-idle
mode as they were trying

to get down and slow down.

All right, the trouble
starts here, at 8,300 feet,

13 miles out from the airport,
minutes before the crash.

PILOT: Amsterdam, Turkish 1951,
descending 7,000, speed 250.

AIR TRAFFIC CONTROLLER
(OVER RADIO):

Turkish 1951, descend to 4,000.

Speed OK for ILS 18 Right.

[beeping]

Radio altimeter.

JOSEPH SEDOR: Would
the crew have known

that, because of
that radio altimeter,

they would have gone
to a retard-flare mode

in the throttles?

No.

It was a common
problem at the airline.

But the crew couldn't see the
risk it posed this flight.

We have an airplane that was
malfunctioning in a very minor

way, but in a way
that, if not caught,

could and did metastasize into
something much more virulent.

AIR TRAFFIC CONTROLLER
(OVER RADIO):

Turkish m descend send to 2,000.

2,000, 1951.

AIR TRAFFIC CONTROLLER
(OVER RADIO):

Turkish 1951, left heading
210, cleared approach.

18 Right.

Left 210 clear
ILS, Turkish 1951.

EXPERT: It left at 210 degrees,
maintaining 2,000 feet,

brings the flight in
right here, 5.5 miles out.

They now have to intercept
the glide slope from above.

NARRATOR: At 2,000 feet, with
the glide slope below them,

the pilots have to reduce their
speed while descending steeply.

Speed, 140.

NARRATOR: They believe the
throttles are moving back for

the descent to the glide slope.

In fact, the auto throttle is
slowing the plane down because

it's gone into landing mode.

It will continue to slow
the plane until it stalls.

JOSEPH SEDOR: What we found is
that, when the flight crew was

doing their before-landing
checklist, each one of them

was doing something
while they should have

been monitoring their airspeed.

For the next 100 seconds, no
one notices what's happening

'til it's too late.

COPILOT: Established
altitude set.

PILOT: 1,000?

COPILOT: Check.

PILOT: Flaps 40.

Speed set.

The experienced
pilot recognized

that the first officer
was probably a little bit

behind on the approach.

So he calls for flap
40 and moves the lever,

informing the first officer
that he has done so.

He's trying to help the
first officer catch up

to the position of the aircraft.

PILOT: Speed break?

COPILOT: Speed brake armed.

Green light.

PILOT: One thing at the time.

Landing gear.

NARRATOR: The plane is now
700 feet from the ground.

COPILOT: Gear down, three green.

PILOT: Flaps?

COPILOT: Flaps 40, green light.

NARRATOR: In their haste to
complete their checklist,

none of the three
crew members noticed

the warnings that their speed
is dropping dangerously.

First, a red bar appeared
on their flight display.

[beeping]

Then, when the air
speed continued to drop,

a flashing box appeared
around their actual airspeed

to draw the pilot's
attention to it.

At this point, no
one sees either.

COPILOT: Cabin report confirmed.

NARRATOR: The aircraft is
now 600 feet from landing.

When things start changing
colors, it's a warning to you.

It's a caution to you
that you're approaching

the limits of the aircraft.

PILOT: Missed approach.

Altitude set.

500.

JOSEPH SEDOR: So all
of these indications

the crew has in front of them,
saying that the aircraft is

slowing down, during that
time, they were still

completing their checklist.

BILL HUFF: Of course,
the aircraft is

getting closer to the ground.

NARRATOR: In fact, it's less
than 500 feet from touchdown.

And right before
the stick shaker

started, the captain
told the safety pilot--

PILOT: Please warn
the cabin crew.

SAFETY PILOT: Cabin
crew, take your seats.

COPILOT: Speed, Sir.

PILOT: I have control.

BILL HUFF: By the time
they advanced the throttles

to full power, it
was unrecoverable.

They were too low for
the engines to catch up.

And that's it.

It's now too late
to save this plane.

[crash]

They all knew about
the altimeter problem

but knowing didn't help.

of a faulty altimeter.

But on February 25, 2009, it
triggered an unusual sequence

of events that brought
down a jetliner

and killed nine people.

The official report
into the accident

blames it on a convergence
of circumstances.

JOHN NANCE: There is
never, ever just one

cause to an airline accident.

It simply doesn't exist.

Maybe someday, God will
slap one out of the sky.

But until then, there's
never one cause.

NARRATOR: The Dutch report also
points out that Boeing could

have realized that the problem
with the radio altimeter system

could have had an
impact on safety.

Given that no one foresaw
how that failure might

cause a crash, the
Turkish Airlines

accident raises a big question.

Are airplanes
becoming too complex?

Investigators have determined
the Turkish Airlines Flight

1951 crashed mainly
because the pilots

didn't recognize the
consequences of the warnings

they were getting.

AIR TRAFFIC CONTROLLER
(OVER RADIO): Turkish 1951,

descend to 4,000--

NARRATOR: This is
not the first plane

to crash because the crew
didn't understand what

their plane was telling them.

JOHN NANCE: Our problem
is not the automation.

Our problem is the depth of
the training and the ability

of the human beings to
recover from mistakes

made in interfacing
with the automation.

NARRATOR: Mica Endsley
studies the relationship

between pilots and technology.

MICA ENDSLEY: And we haven't
really designed the automation

to take best advantage
of what people do well

and take them take
away the parts

that people don't do well.

NARRATOR: In 1996, the crew of
an Aeroperú 757 crashed when

the pilots couldn't decipher
contradictory warnings about

their altitude and airspeed.

The plane flew into
the Pacific Ocean.

61 passengers and 9 crew
members were killed.

In 1995, the flight management
system on a Boeing 757

could and should have steered
the plane to a safe landing

in Cali, Colombia.

But a last minute change
to the flight plan

meant the crew had to
reprogram their computer.

They mistakenly entered a
course that took them headlong

into a 9,000-foot mountain.

159 people died in the crash.

JOHN NANCE: The
cautionary tale here is

that we can get this equipment.

We can get these silicon-based
units, if you will,

so sophisticated that we can't
talk to them, effectively.

And when they go berserk
or they have a problem

or we misprogramed
them, we end up

putting ourselves and
our passengers in danger

while we're trying
to figure out.

NARRATOR: What some
researchers are finding

is that the best technology
shouldn't replace pilots,

but work with them.

MICA ENDSLEY: Really,
integrating people

with technology more effectively
has to do with designing

the displays so that you can't
really understand what it's

doing, and you can
make it simpler

to understand how to make it do
what it is you want it to do.

You shouldn't have
to push 16 buttons

through 8 levels of menus
to figure out what's

going on with the system.

It should be integrated
and presented effectively.

It should be as
easy to communicate

with as the person next to you.

NARRATOR: Boeing and Airbus,
the two largest manufacturers

of passenger planes,
take very different

approaches to the relationship
between humans and technology.

Airbus gives the
flight computer much

of the decision-making
power in the cockpit.

In their view, this
is a way to prevent

a lot of human errors, by making
sure the airplane doesn't do

something it's going
to cause a crash,

even if the humans want them to.

NARRATOR: But Boeing
has a different view.

Its philosophy is to provide
information to pilots

and have them make decisions.

Having more
information is better

for the pilot, having the pilot
in the loop, in the equation,

so to speak.

I kind of like that.

Airbus will
argue vociferously,

and in continuous
fashion, that that view

is archaic and incorrect.

I think the jury is still out.

NARRATOR: The final report into
the Turkish Airlines tragedy

blames the crash of
Flight 1951 partly

on a failure of technology.

JOSEPH SEDOR: The erroneous
radio-altimeter data

caused the auto throttle to
go to a improper mode that is,

of course, not a good situation.

NARRATOR: The
Dutch investigation

asks Boeing to improve the
reliability of the system.

JOSEPH SEDOR: We
learned a lot about

the radio-altimeter
system and how it affects

the auto throttle system.

NARRATOR: Boeing ultimately
changed the throttle system

so that one erroneous altitude
reading would never again

trigger a similar tragedy.

But the report also
faults the crew

for not noticing that
their airspeed was dropping

dangerously low, in spite
of the fact that there

were three pilots on board.

GORDON BETHUNE: Forget that
you got an auto throttle.

You look at the airspeed.

And you look at the altitude.

You look out the damn
window if you want to.

But airspeed is a crucial
component of staying alive

in an airplane.

And you always need to
know what your airspeed is.

NARRATOR: But to Mica
Endsley, the crew's failure

to monitor instruments is
entirely understandable

and may be more the fault of
the instruments than the crew.

MICA ENDSLEY: It's actually
very difficult for people

to be monitors of automation.

One of the things that people
don't do a good job of,

actually, is monitoring.

We're very good on-the-spot
decision makers.

We're very good at coming
up with creative solutions

to problems.

But repetitive monitoring
is the kind of thing

that actually, people
aren't very good at at all.

So what we have to do is design
automation to work with people

in a way that keeps them more
actively, cognitively involved

and in the loop, and
not just monitoring

a piece of automation
to say, is it doing

what it's supposed to be doing?

JOHN NANCE: Who's the
ultimate computer?

The pilot, the individual
who should be able to say,

I don't know what this
thing is doing to me

but I'm punching it off
and flying the airplane.

Fly the jet.

Probably the smartest thing
we ever learned to say,

in our training in the
airlines, fly the jet.

Do that first or
nothing else counts.

That's what they forgot to do.