All language subtitles for Mayday - S02E04 - Deadly Crossroads - Überlingen Crash (Mid-Air Collision) WEBDL-1080p_track3_[eng]

(narrator):
An Airbus A330 loses power
enroute to Hong Kong.

- What the hell was that?
- We now have
two engines stalled.

You know, my blood ran cold.

(narrator): To survive,
the pilots must avoid ditching
in the Indian Ocean.

(screaming)

Soaring six miles in the air,
a British Airways 747 suffers
a mysterious engine flame-out.

(exclamations)
- Mayday, mayday, mayday.

- What the crew had
to deal with was mind-boggling.

(narrator):
And with four engines down,

China Airlines Flight 006
plummets thousands of feet
in just seconds.

- Engines 1, 2 and 3
have lost thrust!
(alarm sounding)

- This airplane
is totally out of control.

(narrator):
In three terrifying events,
with all engines out...

- That is one
of the most dire situations
any crew can be in.

(narrator): ...can investigators
piece together
what really happened?

- Stop. Would you look at that.

- Mayday, mayday.

- It's going up!

(indistinct radio chatter)

- Seatbelt, please. Thank you.

(narrator):
Cathay Pacific Flight 780
cruises at 38,000 feet

over the South China Sea.

(chiming)
- This is your captain speaking.

We'll be starting our descent
into Hong Kong shortly.

(narrator): On a 4.5-hour flight
from Surabaya, Indonesia,

the plane is just 30 minutes
from its destination
of Hong Kong.

- It's a crisp morning;
clear skies, a light wind.

It was a nice day to go flying.

(narrator):
Captain Malcolm Waters

is one of Cathay Pacific's
youngest captains.

His first officer, David Hayhoe,

is an ex-fighter pilot with
the Royal Australian Air Force.

The Airbus A330 is powered
by two Rolls-Royce Trent-700
engines.

Every aspect of flight operation
is aided by advanced computers.

- The engineering and complexity
that goes into them,

and the science that presents
the information,
they're incredible machines.

(narrator): 165 miles
from Hong Kong Airport,

the Airbus leaves
cruising altitude

and begins its descent.

- Airspeed's, uh, 295 knots.

Rate of descent:
700 feet per minute.

It's looking good.

(narrator): The aircraft
is performing perfectly.
(rattling)

And then something goes wrong.
(alarm sounding)

- What the hell was that?

I describe it
as a low, thumping noise
and airframe vibration,

so, you know, David and myself
kind of looked at each other,
like: That's unusual.

(narrator): The flight computer
alerts the pilots to a problem.

(alarm sounding)
- Okay, let's see what we got.

- Engine 2 stall.

(narrator): The plane's
monitoring system indicates

there's an issue
with the right engine,

engine #2.

- Okay... thrust lever #2.

Confirm?

- Confirm.

(narrator):
Captain Waters reduces power
on the engine to idle

to protect it from damage.
- Idle.

(narrator):
The lowest possible level
while still keeping it running.

It has an immediate effect.
The engine noises disappear.

- That's better.

(narrator): Without thrust
from the right engine,

the pilots are now relying
exclusively on the left engine
to get them to Hong Kong.

- A single-engine approach
is not a big deal.

We practise it a lot
in the simulator.

(narrator):
But as the flight crew prepares
for landing,

the left engine, engine #1,
also fails.

(alarm sounding)

- We were relying
on this one engine to get us
safely on the ground,

and now it had exactly the same
symptoms and noises and sounds
as the other engine.

Engine 1 stall.

- Engine 1 stall confirmed.

- Engine 1 to idle.
(alarm sounding)

(alarm stopping)

(narrator): Both engines
are now still running,
but producing no thrust.

The plane is gliding.

- Dammit! Our descent rate
is not looking good.

(narrator): Without thrust,
they won't make it to Hong Kong
or any other airport.

Despite several attempts,
the pilots cannot get
the engines to produce power.

- We've only got
five, six minutes
before we're at sea level.

I... felt fear.

And you have
all those human responses
to fear.

The hair standing up
on the back of your neck,

the tightening of your stomach,
the dryness in your mouth.

(narrator): The pilots confront
the grim prospect of ditching
in the South China Sea.

- I'm calling a mayday.
- Do it.

- Approach, mayday,
mayday, mayday.

Cathay 780 had engine 1 stall
and engine 2 stall.

- Cathay 780, understood.

- The seas looked very rough.
It was a lot of whitecaps.

The swells would be
one to two metres.

I felt that our engines
would act as two big scoops

and would pitch the aircraft
down quite violently,

and that would probably result
in us cartwheeling
and breaking apart.

This cannot be happening.

(narrator): First Officer Hayhoe
begins preparing
to ditch the plane.

Then Captain Waters
gets an idea.

- Okay... try slow movements.

Go slowly. Just...

ease in fuel.

Easy does it.

I was just pinching the side
of the thrust lever
just to move it a millimetre.

Each time I pinched it,
it would just go up
a millimetre.

(narrator): Incredibly,
it seems to be having an effect.

- Rotation increasing
in engine 1.

- It's working.

The rotation of the fan
was increasing from...

28% to 29 to 30 to 32

as I moved this
very, very slowly and gently up.

(narrator): Captain Waters
realizes that the engine won't
go any higher than 74% power.

- That'll have to do.

- We got a thrust setting
that resulted in us being able
to fly level.

We weren't descending any more
and...

that was, like, a huge relief.

(narrator):
With one engine working,

the pilots can now attempt
a landing at Hong Kong Airport.

But there's no margin for error.

- You see that?
Altitude is holding.

- Fantastic.

Okay, approach preparation.

- We did have an engine
that was now functioning,
but I didn't trust it.

Let's do this.

- Okay, flaps 1.

- Gear down.
- Gear down.

(narrator): The safest plan
is to get the plane 5,500 feet
from the ground,

then pull engine 1 back to idle,

reducing speed and altitude...

...in preparation
for a gentle glide
onto the runway.

- Cathay 780,
we have both runways available
for your approach.

- Final items... okay.

(narrator): But just one minute
from touchdown...

- It's overspeed.

(narrator):
An overspeed warning sounds,

a signal the aircraft is flying
too fast.

They should be slowing down.

- Speed checked: 240.

800 feet.

- You know, my blood ran cold.
It just looked completely wrong,

and I was very uneasy that
things were out of my control

and that there was something
that I was missing.

(narrator): Then he sees it.

Engine 1 is still running
at high speed,

too high to land safely.

- I had that whole feeling again
of fear.

Anger.
It was a scary moment.

(narrator): The pilots
have no choice but to risk
a high-speed landing

on a runway
at the edge of the ocean.

- It was our one chance
to get this on the ground,

and we had to make
the best go at it.

(automation): Too low. Terrain.

Too low. Terrain. Pull up.

(narrator): Going 100 knots
faster than normal...

(automation): Pull up.
(narrator): ...Captain Waters
pushes the nose down,

forcing the Airbus
onto the runway.

- Brace!
(narrator): At the end...
lies open water.

- The aircraft
did not wanna land.

And I remember thinking:
Wow, this is it.
'Cause it was very violent.

(screaming)

- Full reverse!
(dramatic music)

(narrator):
The crew deploys reverse thrust

and applies full braking power
to avoid overshooting
the runway.

- No #2 reverse! No decel.

- Immediately,
I just step on the brakes,
hold 'em,

toe brakes to the floor.

(narrator):
Just one faulty engine
is providing reverse thrust.

Will it be enough
to stop the plane
from careering into the sea?

- Full reverse!

(narrator): Cathay Pacific
Flight 780 screeches to a halt

just a few thousand feet
from the end
of the airport's runway.

- I can't believe it.

- We made it.

Nice one.

- It was just this humongous
relief.

I was so happy that, um,
you know, we were gonna go home
and see our families.

(sirens wailing)

(narrator): The passengers
and crew evacuate safely,

with only a few minor injuries.

Hong Kong's Civil Aviation
Department immediately launches
an investigation.

- Thank you.

(narrator): Because the plane's
Trent-700 engines were made
by British company Rolls-Royce,

Anne Evans, of the British Air
Accidents Investigation Branch,
joins the investigation.

- This Trent-700
is a very common engine

fitted to a lot of airplanes
all over the world.

So if there's
an engineering problem
with a particular design,

then we want
to find that quickly.

(narrator): Investigators look
to the plane's flight-data
recorder for answers.

They start with the A330's
engine functions.

- Stop. What's going on here?

(narrator): Right away,
they notice something unusual.

- Thrust levers are moving,
but fuel flow's flat-lining.

(narrator):
Right after the pilots tried
to restore power to the engines

by pushing the throttle up,

the fuel flow remained the same.

- Nothing happens.

The engines just are
not responding at all.
They're just remaining at idle.

Dammit!

(narrator): Investigators wonder
if a fuel-flow problem caused
Flight 780's engine trouble.

- Thank you.

(narrator):
Evans turns to the plane's
in-depth data logs.

They explain in detail
the error messages...
- Engine 2 stall.

(narrator): ...that appeared
on the monitoring system
throughout the flight.

- "Engine 2
control system fault."

(narrator): Anne Evans discovers
that early in the flight,

the computers detected a problem
in a key part of the fuel system
called the main metering valve.

- So the warnings
that were coming up

were warnings to do
with the main metering valve
supplying fuel to the engine.

(narrator):
The main metering valve
is made up of a piston

that slides within a cylinder.

When the pilots move
the thrust levers,

it increases or decreases
the flow of fuel to the A330's
turbofan engines.

When investigators
cut the valve open
to study it...

- That's not normal, is it?

(narrator):
...they find something
they've never seen before.

- What we saw seemed
like very, very fine powder.

Even finer than caster sugar.
Very, very small particles.

(narrator): Microscopic analysis
reveals that the powder

is a type of superabsorbent
polymer, or SAP,

made up of tiny spheres.

- These are organic compounds
designed to absorb water.

That gave us a clue
as to where they'd come from.

(narrator): The powder is used
in refuelling trucks

to prevent water from getting
into the aircraft's fuel tanks.

The refuelling trucks pump fuel
from underground tanks and pipes

through a filter on the truck
and into the aircraft.

If the fuel is contaminated
with water,

the powder in the filter
absorbs it by forming a gel
inside the filter.

But the waterlogged gel
is supposed to stay
in the filter.

It should never end up
in the fuel.

- It is so commonly used
within the industry

for this purpose
of filtering out water.

What we didn't understand was:
How did it get on board
the aircraft?

This one looks
somehow collapsed.

(narrator): Investigators
recover the filters
from the truck

used to refuel Flight 780
at Surabaya Airport.

And when they examine
a sample of the filter
under a microscope,

investigators make
a puzzling find.

- It looks like...
sodium crystals?

(narrator): The powder spheres
are encrusted with salt.

- Had salt water got
into the fuel system?

This one's straight
from the manufacturer.

(narrator): When Anne's team
conducts tests on fresh filters,
exposing them to salt water...

- Well, would you look at that.

(narrator):
...the filters collapse,

just like the ones used
to fuel Flight 780,

allowing both the salt crystals
and white powder spheres
to pass through.

- What was important
was that we demonstrated
we could generate spheres.

(narrator): Investigators
now believe salt water
collapsed the fuel filters,

leading to powder contamination
in the fuel system
of Flight 780.

But one critical question
remains.

- So how did salt water get
into the fuel system?

(narrator):
After a careful review
of the fuel system

at Surabaya Airport,

investigators make
a stunning discovery.

The fuel system is located
close to the sea.

And during a recent upgrade,

the open fuel pipes
were possibly exposed
to groundwater.

Investigators now believe
they know what happened
to Cathay Pacific Flight 780.

The underground fuel supply,
contaminated with salt water,

broke down a filter,
releasing a powder
into the fuel.

The powder jammed
the metering valves,

preventing enough fuel
from reaching the engines.

- Engine 1 stall.
(alarm sounding)

- We had fuel contamination,

and that contamination
throughout the fuel system

led to the seizure
of both main metering valves,

such that the pilot
no longer had control
over the power of the engines.

(narrator): Investigators
believe Captain Waters
was able to restore

some thrust in engine #1

only because
its fuel-metering valve
wasn't yet completely jammed.

Only a small trickle of fuel
was getting through.

- Slowly, slowly. Come on.

- Rotation increasing
in engine 1.
- It's working.

(narrator): Once the spheres
jammed the valve,
it was stuck open...

(automation): Pull up. Terrain.
- Ugh!

(narrator): ...forcing
Captain Waters to make
the risky high-speed landing.

- No #2 reverse!

(narrator): Expert piloting
brought Flight 780
safely to the ground.

(exclamations)
- I can't believe it.

(narrator): Since the accident,
there have been efforts

to improve the regulation
of aviation fuel-handling
and storage.

Manufacturers have designed
the filters to prevent collapse
and powder contamination.

The crew's heroic efforts
in the face of engine failure

save Cathay Flight 780
from all-but-certain disaster.

Total engine failure
is an ultra-rare occurrence
on modern airliners.

- Seatbelt, please. Thank you.

(narrator): Fortunately,
the fast-thinking flight crew
of Flight 780 had some control

of their jet's engines,

allowing them to bring
the plane to safety.

But 28 years earlier,

a bizarre incident puts
the pilots of British Airways
Flight 9 to the ultimate test.

- Oh, my Lord, look at engine 4!

- It's the same on my side.

- When you have
an uncontrollable
and unpredictable event

that puts your airplane at risk,

that takes a whole different set
of skills to resolve.

- Dad! The engine's on fire!

- They've all gone...
All four engines have failed!

(narrator): June the 24th, 1982.

British Airways Flight 9
cruises high over Indonesia.

In a few hours, the plane
and all 263 people on board

are scheduled to land in Perth,
Australia.

Captain Eric Moody commands
the flight.

He's one of the first
ever trained on the 747.

- Roger, check with Jakarta.

- Jakarta Control,

Speedbird 9 over Halim
at level 3-7-0.

(ATC): Speedbird 9...

(narrator):
First officer Roger Greaves
has been co-pilot

for more than six years.

Barrie Townley-Freeman
has been a flight engineer
on these aircraft

for a little longer.

- I'd not flown
with Eric before,

or Barrie.

That was the first time
we'd actually met,

on that, uh, that flight.

Alright, Roger, it's all clear.
Just keep your eyes open.

I'll be back in a moment.
Just gotta use the loo.

(narrator):
But while he's gone...

...conditions in the cockpit
become unusual.

- We started to get these...

pinpricks of light
on the windscreen.

It smelt like sort
of a sulfuric electrical smell,

and I went on that flight deck
expecting to hear

that we had
some electrical smoke
somewhere on the aircraft,

but nothing was further
from the truth.

Anything on radar?

- No, it's clear, not a cloud.

Oh, my Lord, look at engine 4!

It's lit up somehow.

Captain, Captain,
have a look at #1.

- It's the same on my side.

(narrator): The pilots notice
that the plane's engines are lit
by a brilliant white glow.

But it's the flight's passengers
that first spot flames.

- Dad! The engine's on fire!

- There were huge flames
coming out of the back
of the engines,

40 feet long,
shooting out of the back
of all the engines.

What's going to happen?
(alarm sounding)

(narrator):
As fire engulfs the engines,

one of them revs loudly
and flames out.

- Engine failure, #4.

- Once one engine fails,
you call for the drill
to shut that one down.

(narrator):
Then the unthinkable happens.

- Number 2 engine's gone.

- Alright, then.
Begin the engine shutdown.
- No, wait!

They've all gone.
All four engines have failed!

(narrator):
Somehow, all four engines
have completely stopped working.

- Roger, declare emergency.

- Mayday, mayday, mayday.
Speedbird 9.

We have lost all four engines.

(narrator):
Without engine power,

the 747 is now
an enormous glider.

- One of the nightmares
for a commercial airman

is the idea
of losing all your power.

A 747 can glide 120 miles
from high altitude,
but at the end,

you're gonna come in contact
with the surface of the earth
one way or another.

- Alright, begin restart drill.
- Set.

- Battery.
- Check. On.

(narrator): The flight crew
tries to restart the engines.

- Standby power.
- On.
- Anything?

Anything?
- No!

(narrator): Plunging towards
the Indian Ocean,

the crew has to get
their engines going.

- Come on.

- Again, gentlemen.
- Alright, from the top.
Battery.

- Check. On.
(narrator):
Without engine power,

the cabin's air pressure
decreases,

releasing the oxygen masks.

(exclamations)

Captain Eric Moody
is running out of options.

- Come on. Anything?
- No.

- We hadn't had any success
with the drill at all,

uh, despite all the efforts
we were putting in.

But it was the only thing
we had left to cling onto.

(narrator): Descending steadily,

the flight crew prepares
to ditch the Boeing 747
in the Indian Ocean.

- Alright, then.
- I knew it was so difficult
to land airplanes on the sea,

even when you had
everything going for you.

Uh, and I thought:
Well, we haven't got
much going for us here.

I'd never done it before.
(beeping)

(narrator): As a precaution,

Captain Moody decides
to turn the plane back
to the closest airport, Halim,

just outside Jakarta.

If they must ditch,

the chances
of a successful rescue
are higher

if the plane is closer to land.

- Start lever?
- Cut off.
- Fuel pressure?

(indistinct)
- Stand by. Ignition on.

(narrator):
And then, as suddenly
as it stopped working,

the fourth engine
roars back to life.

- Engine 4 back online!

- The noise a Rolls-Royce engine
makes when it starts up,

well, it was wonderful
to hear it.

(narrator): As the plane falls
past 4,000 metres,

another engine coughs
and comes back to life.

- Engine 3 back online!

(narrator): It's followed
quickly by the final two.

- I can't believe it.

Engines 1 and 2
both back online!

(narrator): The crippled jet
is back under full power.
(cheering)

- Oh, my God, Mum!
(applause)

- Jakarta, Speedbird 9.
We are back in business.

(narrator): The crew calls
for an emergency landing
in Jakarta.

- Twelve thousand.

- Let's get this thing
on the ground
as quick as you can.

- Fifty feet.

Thirty feet.

- Reverse.

(laughter)

The airplane just landed itself.
It seemed to anyway.

It kissed the earth.
It was beautiful.

- Wow. That's... that's amazing.
(chuckling)

(narrator): Flight 9
and its passengers and crew
are safely on the ground,

but no one knows what happened.
(cheering)

The next morning,
the flight crew returns

to Halim Airport in Jakarta
to inspect their plane.

The pilots and investigators
are shocked
by what they discover.

- The airplane had lost
its sheen,

and in some places,
it had been sandblasted
quite well,

and all the decals and the paint
had come off.

There really was very little
to see

until they stripped
the engines down.

(narrator): The flight crew
and investigators have never
seen anything like this before.

And their surprising discovery
changes aviation-safety
procedures forever.

(Ferguson): This was an event
which was unique
in aviation history.

(narrator): The engines
from British Airways Flight 009
are sent to their manufacturer,

Rolls-Royce, in the UK.

Engineer Malcolm Grayburn
and his team

are tasked with figuring out
what caused them all
to mysteriously flame out...

- Dad! The engine's on fire!

(narrator):
...and come back to life.

- We did do a forensic analysis
of the engines.

(narrator): Grayburn is stunned
by what he discovers.

The engines were choked
with fine dust,

pieces of rock and sand.

On close study,
he discovers that the debris
is volcanic ash.

The evidence points
to a clear suspect.

On the night of the flight,
the Mount Galunggung volcano,

located just 100 miles
southeast of Jakarta,

erupted unexpectedly.

The enormous ash cloud
rose nine miles high,

right into the path
of British Airways Flight 009.

Never before
had a volcanic cloud
seriously affected an airplane.

- Mayday, mayday, mayday.

We have lost all four engines.

(narrator): A turbofan jet
engine works by sucking in
enormous amounts of air.

The air is then
highly pressurized
by the engine's compressor.

This tightly packed air
is mixed with fuel and ignited.

The force of this reaction
propels the jet through the sky.

- The temperature
in the combustion chamber,

where this ash
is flowing through,
are around 2000° Centigrade,

and so the volcanic ash we know
melts at about 1300, 1400°.

(narrator):
But when the liquid ash
reached deeper into the engine,

it cooled slightly,
turning into a sticky,
molten goo.

It attached itself to the engine
and began choking it.

- We got a fundamental
disturbance of the airflow
in the main core of the engine,

which caused the engine
to backfire.

- Engine failure, #4.

(narrator): But if the engines
were choked with ash,

how did they suddenly
roar back to life?

- Engine 3 back online!
(revving)

(narrator):
What Grayburn discovers next

is that a remarkable piece
of chemistry saved the plane.

- As soon as you came out
of the volcanic ash,
everything cooled down,

it was enough for this stuff
to break off

and allow the engines
to restart.

(revving)

- I can't believe it!

Engines 1 and 2
both back online!

(narrator):
The pilots of Flight 009
are celebrated as heroes

for overcoming
total engine failure

and guiding their plane
and its passengers to safety.

But their miraculous discovery
also provokes a giant leap
forward in aviation safety.

- Now, more than 30 years later,

there's a worldwide system
in place

to warn pilots
when there's a risk
of volcanic ash in the air

so the aircraft can avoid
this kind of hazard.

It has worked wonderfully
over the last few years.

- Here you go, gentlemen.
- Hey, there she is.
Hey! Melissa.

(narrator):
But total engine failure
happens again

just three years later.

China Airlines Flight 006
cruises on autopilot

39,000 feet above the Pacific.

- It was a routine
commercial flight.

I sat there and read some books,
went to sleep.

(narrator): While many
of the 251 passengers doze,

the plane nears its destination
of Los Angeles, California.

In the cockpit,
the experienced three-man
flight crew,

led by Captain Min-Yuang Ho,

has amassed
more than 38,000 flight hours.

But as the crew prepares
for an easy landing...

- Engine 4 is giving us
weak thrust.

(narrator):
...the flight engineer
spots something troubling.

There's a problem
with one of the engines.

When the engine is throttled,
it doesn't respond.

- We're losing speed.

(narrator):
Then the strange situation
suddenly gets much worse.

- Engine 4 flamed out.

(narrator): Engine 4
stops working completely.

- Take a look
at engine-out procedures.

Work out a three-engine
cruise altitude.

- Yes, Captain.

(narrator):
Without the fourth engine,
the plane slows down.

- Airspeed: 240.

- Reignite engine 4.

- Yes, Captain.

(narrator): At 39,000 feet,
there isn't much oxygen,

so the chances
of a successful relight
are slim.

- No response, Captain.

(narrator): As the crew tries
to restart their engine,

their plane slowly begins
to roll to the right.

- We're banking right, Captain.
Airspeed: 230.

(narrator):
As the plane loses speed,
it's in danger of stalling.

- Altitude, hold off. Nose down.

(narrator):
Hoping to increase his speed,

Captain Ho tries pushing
the plane's nose down.

Nothing the crew does
seems to help.

Their jet is banking
more and more steeply.

- I'm disengaging autopilot.

(screaming)

(narrator):
Captain Ho takes manual control
of the aircraft.

But he struggles as the plane
veers into thick cloud.

He can't see the horizon.

Instruments that normally
would help him
keep the plane level

don't seem to be working.

- I've lost ADI!
(alarm sounding)

- The ADIs have malfunctioned.

- It's going out of limits!

(narrator): Just minutes after
engine #4 stops working,

the China Airlines flight
suddenly stalls

and begins falling from the sky.

(narrator): A 747 jumbo jet
is flipping upside down.

China Airlines Flight 006
plunges towards
the Pacific Ocean.

- People just popped up
like popcorn, hitting the cabin.

(screaming)

(narrator): In the cockpit,
the flight engineer struggles
against the plane's wild motion

to restart his fourth engine.
(beeping)

The G-forces are so powerful
that the flight engineer is
pinned to the control pedestal.

- Ignition negative!
(beeping)

(narrator):
But his attempt is unsuccessful.

Then, the situation
suddenly gets a lot worse.

- Engines 1, 2 and 3
have lost thrust!

(groaning)
No response, Captain!

- Altitude: 370!

360! 350!

(narrator): In the cabin,
the G-forces are punishing.

(screaming)
- I closed my eyes.

I thought I was gone.

- Airspeed 80 knots and falling!

(beeping)
No response!

The engines are flamed out!

(narrator): The stress
of the dive tears the landing
gear doors off the plane.

(woman sobbing)
In less than a minute,

the plane drops
almost 20,000 feet.
(screaming)

- Emergency! Emergency!

(narrator):
The plane suddenly breaks free
from the clouds.

- I can see the horizon!

- Altitude: 10,000 feet!

(narrator): The captain uses
the horizon as a reference
to level the plane

just 30 seconds
before they hit the ocean.

Now the G-forces
suddenly change direction.

Passengers are pressed
to the floor,

feeling five times
their normal weight.

- You know,
the G-force was so strong.

And... I weigh 200 pounds,

so my weight
was almost 1,200 pounds.

(narrator):
It's a race against time.

(beeping)
And finally...
- ADI's coming back.

(narrator):
...the plane starts to win.

- ADI's coming in.

(narrator): As mysteriously
as the incident began,

three of the plane's engines
regain power.

- Engines 1, 2 and 3
are coming back.

Engine 4 still negative.

(beeping)
- Reignite engine 4.
- Yes, Captain.

(narrator): Once again,
the flight engineer tries
to reignite the fourth engine.

(beeping)

But now...
(revving)

- Engine 4 reignited.

(narrator): For the first time
in minutes, the plane
is flying under control.

- They saved the airplane.

That was a masterpiece
of flying.

- Ladies and gentlemen,
this is the captain speaking.

(sighing)
Is anyone hurt?

(exclamations)
Do we have a doctor on board?

(narrator): Captain Ho declares
an emergency...

...and diverts the flight
to San Francisco.

(all cheering)

- He made one of the best
landings I've ever seen.

I mean, it was just...
a perfect touchdown.

(narrator): On the ground,
the full extent of the damage
to the plane shocks everyone.

- Parts of the entire tail plane
at the end were ripped off,

as though a tornado
had come through.

(narrator): Two-dozen passengers
have minor injuries.

A near-disaster was avoided,
but what had gone wrong
in the first place?

The National Transportation
Safety Board is on site
that very day.

The cockpit voice recorder
is sent to Washington.

But it's designed
to tape over itself
every 30 minutes.

None of what happened
in the cockpit

during the terrifying plunge
from the sky remains.

- Without a cockpit voice
recorder,

we had to reconstruct
what the crew said
and how they interpreted things,

and what was going on
in the cockpit
to the best of our abilities,

with the other data
that was available to us.

(narrator): But the plane's
flight-data recorder,

which suffered
intense electrical damage,

has several gaps in the data log
that have to be painstakingly
reconstructed.

In the meantime,
investigators begin by
inspecting the plane's engines.

Despite the horrific dive
through the sky,

engines 1, 2 and 3 are found
to be in working order.

Engine 4,
the first engine to fail,
gets special scrutiny.

- They believed that the engine
had flamed out,

or that there was something
seriously wrong with the engine.

(narrator): After examining
every inch of engine 4,

investigators determine
that it was faulty.

- Engine 4 is giving us
weak thrust.
(narrator): And at 39,000 feet,

it wasn't able to produce
adequate thrust to keep
the faulty engine running.

- Engine 4 flamed out.

- The loss of thrust
on a four-engine airplane
is a minor event,

and the airplane will fly
on three engines
with no difficulty.

(narrator):
Investigators are puzzled.

If the 747
was never in immediate danger,

is it possible that the plane's
swift plunge

began somewhere other
than in the engines?

(all screaming)

(narrator): The crew
of China Airlines Flight 006

are brought in
for intensive interviews
by the NTSB.

- I heard the captain...
(narrator): Without a cockpit
voice recorder,

investigators rely
on the pilots' statements

to piece together
how a manageable problem
became a near-catastrophe.

- I've lost ADI!
(alarm sounding)

- The ADIs have malfunctioned!

- It's going out of limits!

- When we started banking right,

engine 4 was already flamed out.

We started to descend faster,

and engines 1, 2 and 3
also failed.

(alarm sounding)
Engines 1, 2 and 4
have lost thrust!

(narrator):
But the pilots' stories
don't match the flight data,

which clearly shows
that engines 1, 2 and 3

were running perfectly
the entire flight.

They never lost thrust.

What could possibly have caused
the plane to flip, twist,
and hurtle towards the sea?

(screaming)

After months of analyzing
the flight data
and pilot interviews,

the NTSB can finally
piece together

the series of events
that led to this near-disaster.

Just after 10:00 Pacific time,
the flight engineer spots
the engine trouble.

- Engine 4 is giving us
weak thrust.

(narrator):
He struggles to fix the problem.

But investigators discover
he misses a basic step.

He leaves the engine's
bleed-air valve open.

The bleed-air valve regulates
the flow of compressed air
from the engines into the cabin.

When an engine
isn't working properly,

the valve is supposed
to be closed

so the engine can use
all available air to restart.

- It's... a little puzzling
that the flight engineer
didn't shut off bleed air.

The end result
is that the engine,
which is slow to start,

won't start at all.

(narrator): Unwittingly,
the flight engineer has started
a ticking clock.

Engine 4 is slowly losing
its ability to stay lit.

- We're losing speed.

(narrator):
With more engine power
on the left wing than the right,

the China Airlines flight
begins turning.

- The proper thing to do
would've been to step
on the rudder.

That would've produced a, uh...

...twisting force, so to speak,
that would've overcome
the imbalance of the engines.

(narrator): Instead of adjusting
the rudder himself,

Captain Ho continues to let
the autopilot fly the jet.

But the autopilot isn't designed
to move the rudder.

The autopilot can adjust
the ailerons and spoilers
on the plane's wings,

but these flaps
aren't strong enough

to overcome the imbalance
that the plane is experiencing.

- I'm disengaging autopilot.

(screaming)

(narrator): By the time
Captain Ho takes manual control
of the plane,

it's already banking alarmingly
to the right.

- I've lost ADI!

(narrator):
While he fights for control,

the 747 flips onto its back
and enters a vertical nosedive.

Moments later,
as G-Forces rapidly increase,

the flight engineer
makes another enormous mistake.

- We started to descend faster,

and engines 1, 2 and 3
also failed.
(beeping)

Engines 1, 2 and 3
have lost thrust!

(narrator): But the engines
are perfectly fine.

Investigators now know
the throttles
were deliberately set to idle

in an attempt to slow
the jet's furious fall,

something the flight engineer
doesn't notice
in the chaotic dive.

- If he had not seen the captain
pull the power to idle
on the... the engines,

he would reasonably assume
that the fact that they went
to idle was a problem,

rather than intentional.

(narrator): An investigation
that starts with faulty engines
reveals that, in fact,

a chain of mistakes by the crew
puts Flight 006 just moments
from certain death.

- The crew didn't behave
as they should've behaved.
Pilot error.

(narrator):
But whatever mistakes
the flight crew made...

- ADI's coming in.

(narrator):
...they still achieve
the ultimate goal.

- The one big thing
they did right...

...is they saved the airplane.

- China Airlines 006
is an extreme example

of why high-altitude-upset
recovery training
is so important.

It became a learning experience
based on what this crew did.

(narrator): When an aircraft
loses engine power...

...the response must be quick,
concise and efficient.

- I can't believe it.
- We made it.

- When you've got
an engine problem,
when you've lost an engine...

- Dad! The engine's on fire!

- ...the only thing you have
to rely on is literally
your training as a pilot.

- I can see the horizon!

- And it makes all
the difference in the world.
(tires squealing)

(cheering)
(exclamations)

Subtitling: difuze