All language subtitles for Mayday.Air.Disaster.S25E04.Second.Thoughts.1080p.AMZN.WEB-DL.DDP5.1.H.264-BLOOM_track3_[eng]

(Dynamic music)

♪

(Text on screen)

(narrator): Descending into
heavy fog above Luxembourg...

- The hell is that?!

(narrator): ...something goes
disastrously wrong

on Luxair Flight 9642.

- The airplane was impossible
to recover.

(heavy crash)

(narrator): 20 of the 22 people
onboard are killed.

- A lot of people died that day.

It was an accident that
was hard to understand.

- I can't find anything wrong
with either engine.

(narrator): But when
investigators analyze

unusual sounds from
the cockpit...

- It's a match?
- Mm-hmm.

(narrator): ...they hear
the pilots do something

which should be impossible.

- It's not supposed to happen.

There's supposed to be things
that prevent it from happening.

- So it's not as foolproof
as we thought.

(♪♪)

- Mayday! Mayday!

(opening theme)

(soft pensive music)

(narrator): It's just before
10:00 in the morning

at Luxembourg's
International Airport.

A layer of fog blankets
the runway,

preventing planes from landing.

- Cargolux 778 maintain
runway heading

until LUTAX, then use
own navigation.

Luxair 403 enter Diekirch
hold flight level 60.

I will vector you later
for ILS approach.

(narrator): Controllers
are busy putting planes

into a holding pattern while
waiting for the fog to clear.

- Luxair 4452 enter Diekirch
hold flight level 90.

QNH is 1023.

Luxair 8362 descend level 80
to enter Diekirch hold.

Current RVR is 250.

(narrator): There are three
planes circling 16 miles north

of the airport at a position
known as Diekirch.

- In a situation with
low visibility,

lots of holding,
lots of aircraft

having different requirements,

the level of stress
is fairly high.

Focus is really important.

You gotta concentrate on
everything that you're doing.

- Luxair 9642 enter Diekirch
hold flight level 90.

There will be vectors later
for an ILS approach

on runway 24.

- That's all understood,
Luxair 9642.

(narrator):
One of the planes being directed

to the holding pattern
is Luxair Flight 9642.

The plane is a
Fokker 50 turboprop

heading to Luxembourg
from Berlin.

- The Fokker 50 was a great
performing aircraft overall.

It's a commuter airplane,
to be flown in Europe.

We flew the aircraft
day and night,

in all weather conditions.

(narrator): There are
19 passengers on the flight.

Most are German business
officials

travelling to Luxembourg.

The first officer
on this morning's flight

is 32-year-old John Arendt.

- I'll brief the folks.

Ladies and gentlemen,
good morning.

Uh, unfortunately, the fog
in Luxembourg is so dense

that at the moment
we cannot land.

So we'll have to wait a little
bit for an improvement.

We will proceed to
a holding pattern

while we wait for
the weather to clear.

We'll keep you updated as soon
as we have some news.

(narrator): The captain is
26-year-old Claude Poeckes.

- And Luxair 9642 is

reducing speed to 160.

- Roger 9642.

(narrator): The crew navigates
toward the holding area

north of the airport.

- What time can we hold till?
How much fuel will we need?

- Uh, 550...

uh... 700.

No, we'll need 8-50 when
we leave the hold.

- No. We need fuel to reach
till our alternate

plus 20 minutes reserve.
So we'll still need 600 kilos.

- Yes, but I want to keep--

(controller on radio): Luxair
9642 descend to 3,000 feet

on 1023, turn left heading 130.

(narrator): Before they reach
the holding point,

the crew receives instructions

to turn towards the airport
and begin descent.

- Is that for us?
- Yes.

- Uh, descend to 3,000 feet.
Say again the heading.

(controller on radio):
130.

- Left heading 130,
Luxair 9642.

What kind of crap is that?

(narrator): The new instruction
takes the crew by surprise.

- If you suddenly get startled
that you are now number one,

and turning left, and descending
for your approach as number one,

this can put you in a situation

which would add
to your workload.

- What's the RVR now?

- I don't know,
should we check with dispatch?

- Yes.

(narrator):
RVR is Runway Visual Range.

It's the minimum visibility
on the runway required

by a landing aircraft.

For the Luxair Fokker,

that distance is 300 metres,
or 984 feet.

- If the runway visual range
is below 300 metres,

you are not allowed
to start the approach

or to land the aircraft.

- Dispatch, 9642,
what's the current RVR?

(dispatcher on radio):
Uh, 275.

- 275 metres.
What do we do now?

- I don't know.

- If they don't have
that visibility, they go around

and they'll probably get
vectored for another approach

unless the RVR is too low,
then they're gonna be vectored

to the holding pattern
at Diekirch.

- So are we holding or
is this for an approach?

- It's for an approach.

(controller): Luxair 9642

turn right heading 220.

Cleared for approach.

(Arendt):
- Right heading 220, and uh,

cleared for approach, 9642.

- Tell him that if at ECHO
we don't have 300 metres

that we'll do a go-around
and enter the hold.

(narrator): The pilots
come up with a compromise.

They'll continue their approach,

but if runway visibility
doesn't improve,

they'll abort and join
the holding pattern.

(Arendt): We need 300 metres
for the approach.

- 9642, copied.

Continue your approach.
I'll keep you advised.

(foreboding music)

(narrator): Passengers still
believe they're headed

for an extended hold.

(engine buzzing)

(Arendt):
Speed's 95, 105, 109.

- Landing altitude?
- 275 metres.

- Set.

(narrator): The flight is now
only 5 miles from the runway

and there's no word that
visibility has improved.

Captain Poeckes makes
his decision.

- Okay, we'll do a go-around.
Missed Approach.

- Ground Idle Stop off.

(controller):
Luxair 9642,

RVR is 300 metres.

(narrator): But before the crew
can execute a go-around,

the controller issues
a last-minute update

to runway conditions.

- 9642 continuing approach.

(narrator):
The visibility now meets

the Fokker's minimum
requirements.

The crew's plans have
changed again.

(Krieger): Things change rather
quickly for a flight crew

when they're doing an approach

which requires really
precise coordination

among the crew members
to make sure

that everything
goes smoothly

and that they're stabilized
on the approach.

(engine buzzing)

(narrator):
4 miles from the airport,

Flight 9642 is at an altitude

of 1,500 feet.

- Flaps?

- Uh, we are flaps 10.

- 9642, you are cleared to land,

wind 180 degrees,
5 knots.

(tense music)

- Uh, gear down?
- Yeah.

- Cleared to land 9642.

(narrator):
The flight is now two minutes

from landing in Luxembourg.

(hubbub, whirring)

- The hell is that?!

(engine buzzing)

(narrator): Something has gone
wrong with the engines.

(whirring, clicking)

(passengers yelping)

- Oh!

(narrator):
Now at less than 500 feet,

Flight 9642 plummets
towards the ground.

(screaming)

(GPWS):
Terrain. Terrain.

- Pull, pull, pull, pull,
pull, pull, pull!

- The airplane suddenly
went into a rapid

and uncontrollable descent
in a very low altitude,

which was impossible to recover.

(engine buzzing)

(passengers screaming)

(devices beeping)

- 9642, Luxembourg.

Luxair 9642, Luxembourg.

Luxair 9642,
Luxembourg, do you read?

We have a possible crash
of a Fokker F50

on final approach to runway 27.

Please stand by.

(sirens wailing in distance)

(narrator):
The wreckage is located

2 miles east of the airfield.

(helicopters buzzing)

Of the 22 people on board,

only two survive the crash,

including Captain Poeckes.

This is Luxembourg's deadliest
aviation disaster.

(melancholic music)

(McNair):
Well, this accident is serious

because there was loss of life.
A lot of people died that day.

And it was, uh, an accident
that was hard to understand.

(narrator): Investigators will
need to examine the wreckage

of Flight 9642 to determine

why a landing at a modern,
well-equipped airport

went so terribly wrong.

(heavy music)

- The tail hits here.

The left wing scrapes
some trees,

and then the plane skids
across the road.

(narrator): The wreckage
tells investigators

that Flight 9642 hit the ground
in a nose up position.

- The initial hypothesis
would be that, in fact,

they were trying
to avoid the ground

when the aircraft
hit the ground.

- Engine failure? Windshear?

Mechanical issue?

(narrator): The debris pattern
leaves investigators

with a few obvious
possibilities.

(Friesacher): Aircrafts
don't crash short of runways.

Do they have false indications?
Were the engines running?

So there are lots of things you
have to initially think about.

(narrator): As they gather
wreckage from the accident site,

investigators wonder if
the controller can provide

any insight into the flight's
final minutes.

- Anything unusual?
Out of the ordinary?

- The whole day was
out of the ordinary.

(narrator): The controller
explains that the weather

prevented planes from landing,
forcing them into a hold.

- And that includes Flight 9642?

- At first, yes.

(heavy sigh)

Luxair 9642 enter Diekirch
hold flight level 90.

But before they reach the hold,
the weather cleared.

Luxair 9642 descend
to 3,000 feet on 1023,

turn left heading 130.

(narrator): He also states

that because of its position,

Flight 9642 was the first plane

directed to the airport

when the weather began to clear.

- They needed 300 metres
of visibility to land,

which we got at 10:05.

So I cleared them to land.

- Even though they were heading
for the holding pattern,

the controller saw
an opportunity.

They were in an ideal position

to the final approach fix
and also the Luxembourg Airport.

- And then?

- That was the last we spoke.

- No emergency call?
- No.

Nothing.

(narrator):
The controller can't explain

why the Fokker ended up
hitting the ground

2 miles from the airport.

(pensive music)

- From an air traffic
control standpoint,

there was nothing
in the communication

between the aircraft
and air traffic

to indicate that there was
any problem whatsoever

with the aircraft at all.

(narrator):
Only Captain Poeckes can answer

why the Fokker went down
short of the runway,

but he's been hospitalized
and is in a coma.

Investigators will need
to piece together

the final minutes
of the flight without him.

(Friesacher): With the captain
not being available,

the objective evidence,

the physical evidence
talks to you.

(narrator):
They begin by studying

the engine components
for any signs of failure.

- They look like they're
in pretty good shape.

(Friesacher):
Engines normally hold

the aircraft in the air,
and they fly towards the runway.

So I would suggest something
happened to the engines

that they didn't make it

to the runway
in the first place.

- No fire, no damage
to any components,

the rotors are fine,
fuel lines are intact,

intake is clear, pumps
and PCUs all check out.

I can't find anything wrong
with either engine.

(narrator): The state of
the engines is puzzling.

If both were in good
working order,

what could have caused
the flight to fall from the sky

just short of the runway?

(mysterious piano music)

- This is where they're turned
for the approach.

(narrator): Investigators use
Luxembourg's radar data

to recreate Flight 9642's
flight path.

- Seven minutes to impact.

- They're at 9,000 feet

when they're cleared
for the approach.

Now he descends even
more steeply,

and at 7,000 feet per minute.

- They're only 4 miles away
from the runway.

15 seconds later,
they hit the ground.

Here's the glideslope.

(soft investigative music)

- Whoa.

(narrator): When investigators
compare the plane's descent

with the recommended descent,

they see that the flight was
300 feet too high

throughout the final stages
of its approach.

- That explains why they were
in such a hurry

to lose altitude.

- 300 feet above
the glide slope,

this is a real problem
because you now try

to descend the aircraft,
slow down the aircraft,

and configure everything
at the same time,

which is nearly impossible.

(narrator): Why did the pilots
allow their plane

to get into such
a difficult situation?

- Not a good idea to be
rushing on an approach at all,

especially in low RVR,
dangerous actually.

(investigative music)

(Poeckes on CVR):
Heavy fog.

It will be a hard landing.

(narrator): The team listens
to Flight 9642's

Cockpit Voice Recording, or CVR,

for clues that can explain

the pilots' dangerous
predicament.

- Okay, they know the weather's
going to be an issue.

(Poeckes on CVR):
I'll call dispatch.

Dispatch, good morning, 9642.

(dispatcher):
9642, good morning.

- How is the weather
at the moment?

(dispatcher):
RVR is 250 at the moment.

If it doesn't get better,

you will be diverted
to Saarbrücken.

- Okay, thank you.

Oh no.
I will not go to Saarbrücken.

(soft chuckle)

- I'm with you.

(terminal on CVR):
Wind 1-10, 4 knots.

Expect ILS approach,

runway 27, transition level 60.

- He does not want to divert.

(controller on CVR):
Luxair 9642 enter Diekirch

hold flight level 90.

- They're being directed
into the holding pattern.

(Arendt on CVR): No. We need
fuel to reach to our alternate

plus 20 minutes reserve.
So we'll still need 600 kilos.

- Okay. Good.

They want to make sure
there's enough fuel

to reach their alternate.

(Poeckes on CVR):
Yes, but I want to keep--

(controller on CVR): Luxair 9642
descend to 3,000 feet on 1023,

turn left heading 130.

- And then they're hit
with a new plan.

(intriguing music)

(narrator): The recording
reveals that the pilots

were surprised
by the instruction

to begin their approach.

- What kind of crap is that?

- They were not happy about
the change of plans.

(narrator):
The sudden change meant

that instead of proceeding
to the hold,

the pilots quickly
initiated a left turn,

and began a steady descent
towards the runway

all while configuring
their plane for landing.

- So the crew were forced
to rush themselves

down to the final approach fix.

(narrator):
The rushed approach

now becomes the focus
of the investigation.

(controller on CVR): Luxair 9642
turn right heading 220.

Cleared for approach.

- Okay, they're starting
their approach.

- For a low visibility approach,

properly briefed and performed,

it's very structured, organized,
and standardized,

so each pilot knows exactly

which task they have
to do at which time.

- Should we switch
the seatbelt sign on?

- Yes, yes. Not a bad idea.

(soft pensive music)

Localizer captured.

- Uh, check.

Missed approach heading.

- They're not running
a checklist.

They're just throwing out
random steps.

(narrator):
Over the next few minutes,

investigators hear several
clear indications

that the pilots are improvising
this unexpected approach.

(Hildebrand):
You must be fully established,

which means gear down,
flaps extended,

landing checklist completed,

speed and altitude all
at the correct spot.

- Hey, are we at the beacon yet?

- You should have it
dialled in by now.

- I can use the DME instead.

- Yeah, yeah, yeah.

(narrator): Even basic steps
such as configuring

the navigation system
aren't performed.

(Friesacher):
Flying an aircraft is about

a precise following of certain
steps at certain times.

It's starting on an approach
involving all the crew members.

It's about detailed planning.

- They're skipping steps
and improvising the procedures.

The change of plans
caught them by surprise.

(pensive music)

- They're racing against
the clock.

- They started
to rush themselves

in a quite high
workload environment,

trying to get the airplane down,
and doing the approach briefing,

all at once, which was
quite tricky to achieve.

(narrator): Did the rushed
approach result in the pilots

being too high as
they neared the runway?

- They're getting closer
and closer to the airport.

And at 3.5 miles out,

they should be at 2,500 feet,

but they're at 3,000 instead.

(♪♪)

(Arendt): Flaps?
- Oh, we are flaps 10.

(controller):
9642, you are cleared to land.

(narrator): Instead of managing
their altitude and speed,

they're rushing to get their
plane properly configured.

(Hildebrand):
Speed and altitude control

is actually important
for every approach,

but especially for
a low visibility approach

where you have to be established

much earlier than
on a normal approach.

- So why all the confusion?

It can't just be
the last-minute approach.

- I don't think they thought
they'd be able to land.

Have a look.

- RVR, RVR, RVR...

(narrator): The cockpit
recording makes it clear

to investigators that
the crew didn't think

they'd have the required
visibility to make the landing.

- What's the RVR now?

- I don't know,
should we check with dispatch?

- Yes.

- They're told they have
a visual range of 275 metres.

But they need 300 minimum
to land.

- They're not sure
how to proceed.

- Their plan is to do
a go-around

if the visibility hasn't
increased by the time

they get to the outer
marker here.

- The outer marker can be seen
as a decision or a cutoff point.

Once you pass the outer marker,

the RVR must be at
the required minimum.

- But as soon as they get
to the outer marker,

they get the magic words...

- "300 metres."

- Luxair 9642,

RVR is 300 metres.

You are cleared to land,
wind 180 degrees, 5 knots.

- But they're too high and need
to lose altitude fast.

(narrator):
The CVR explains why

the pilots ended up above
their target altitude.

They were rushed
into the approach

and fixated on the poor
runway visibility.

- Okay, so how does that lead
to a crash 35 seconds later?

(controller on CVR):
9642, you are cleared to land.

(Arendt on CVR):
Uh, gear down?

(Poeckes on CVR):
Yeah.

(Arendt on CVR):
Cleared to land 9642.

And done.

(hubbub)
(static, whirring)

(Poeckes on CVR):
The hell is that?!

(exhales)
Oh!

(GPWS):
Terrain. Terrain.

- What just happened?

- In the last few seconds
of the CVR recording,

there was a loud noise.

The crew was startled by this.

- What happened in those
last 20 seconds?

- And what was that noise
we heard?

(investigative music)

(hubbub, whirring)

- The hell was that?!

(passengers yelping)

(engine buzzing)

(♪♪)

(narrator):
Investigators hope

the Flight Data Recorder,
or FDR,

can solve the mystery
of what went wrong

in Flight 9642's final seconds.

- Okay, cruising along
at 3,000 feet and 160 knots,

then they start to descend,
go flaps 10

and accelerate rapidly
towards the ground.

- Let's see what the engines
were doing.

- What's happening here?

Turbine RPMs drop,

torque drops down to zero.

Looks like he's gone down
below Flight Idle,

into Ground Mode.

(narrator): Ground Mode changes
the angle of the propellers

so they can move
the plane forward

while it's on the ground.

It's never used in the air.

- But then...

Turbine RPM spikes,

fuel flow and torque increase.

- All while the altitude
starts to plunge.

- Could they have gone
into Beta Mode?

(intriguing music)

(engine rumbling)

(narrator): Beta Mode is
basically reverse thrust.

The propellers are positioned
to move air forward

instead of back.

It's used to help stop the plane
after it touches down.

- If you would put
the power levers

into Beta Mode in the air,

this could lead
to loss of control

where recovery might
not be possible.

(narrator): Did the pilots
of Flight 9642

put their engines into
reverse and if so, why?

- Can we hear the last
20 seconds of that CVR again?

(Arendt on CVR):
And done.

(hubbub)
(static, whirring)

(Poeckes on CVR):
The hell is that?!

Oh!

(GPWS):
Terrain. Terrain.

- It's the propellers
going into reverse.

(narrator): Investigators
now have an explanation

for the deafening sound
on the CVR.

- This is almost like
hitting the brakes.

The aircraft would immediately
dive into a rapid

and uncontrollable descent.

- How could the engines end up
going into Ground Mode

and then into reverse Beta Mode?

How is that even possible?

- The turboprop airplane,
like the F50,

it had a lot of safety, uh,
features that would prevent

the propeller from going
into Beta Range in flight.

(narrator): Before a plane can
be put into reverse mode,

the thrust levers must first
pass through Ground Mode.

A lock prevents this
from happening.

Pilots can switch
the lock off in flight

to prepare for landing.

(engine rumbling)

- Ground Idle Stop off.

(narrator): First Officer Arendt
performed that step

as part of his Descent
and Approach checklist.

With the lock disabled,

pilots can lift the Ground
Range Selector

and move the thrust levers
to Ground Mode

after landing to help
slow the plane.

But instead, the data reveals
that the engines

went into Ground Mode 25 seconds
before the plane crashed.

(dramatic music)

- Did they do it on purpose?

(McNair): The question is,
"How did they get there?"
Did the crew select it?

Did they do it deliberately?

Was it something bad
that happened,

the safety defences didn't work?

These are all things that
have to be looked at.

- Okay, we're recording.

Let's start with
the taxi lights.

(narrator): To find out if
the crew intentionally put

the plane into Ground Mode
before they were on the ground,

they record a number
of different sounds

in the cockpit of
another Fokker 50.

(pensive music)

- Every switch has
a sound attached to it.

- Okay, let's try flaps to 10.

(intriguing music)

And now the Ground Range
Selector.

And that does it.

- And this, uh, can be
forensically analyzed

and filtered out.

- And you compare that
to what you find from
the Cockpit Voice Recorder.

- These three sounds were
picked up on the CVR.

Let's start with this.

(clicking)

We were able to confirm
that this sound

is the taxi lights
being switched on.

(clicking)

(♪♪)

(rattling)

The test recording confirms
that that's the flap handle

being moved to flaps 10
position.

(rattling)

And there's this.

(clicking)

We compared it to the sound
recorded on the test plane.

- It's a match?
- Mm-hmm.

(narrator):
The audio analysis confirms

that Captain Poeckes
deliberately lifted

the Ground Range Selector
and moved his throttle

to Ground Mode while
the plane was making

its approach to the airport.

- The key element found
in the sound spectrum study

was the power lever was,
in fact, moved

below the Flight Idle gate.

And this was something that
meant the pilot had to do it.

(soft investigative music)

- Okay.

So we know he did this
on purpose.

But why?

- There is no maneuver
or procedure

asking the pilots to actually
lift the Ground Range Selector

in flight and pull the power
levers below Flight Idle.

It's a prohibited,
non-standard procedure

and should never be done
by the pilots.

(narrator): What could have
prompted the pilots

to put their engines
into Ground Mode?

- He's 5 miles away
from the airport

when he decides to land,
but he's 300 feet

above the glideslope
and his speed is 165 knots.

If he wants to get down
to the glideslope,

he needs to descend rapidly,

but his speed is
already quite fast.

So instead,
he slams on the brakes.

- Once the power levers are
in Ground Idle,

this will produce extra drag
on the propellers,

reducing the speed, and also
allowing the aircraft

to descend at the same time.

(controller): Luxair 9642,
RVR is 300 metres.

(narrator):
Investigators believe that
when the crew is told

that runway visibility
has improved,

Captain Poeckes moved
his engines to Ground Mode

to quickly reduce speed
and lose altitude.

- Not sure that'll do it.

9642 continuing approach.

Flaps?

- They should have made a better
decision and go around,

reposition, and fly
a proper approach,

or divert to the alternate
and not forcing it in.

- Okay, we can explain putting
the engines into Ground Mode,

but reverse?

(hubbub)
(beeping, whirring)
- The hell is that?!

(passengers screaming)

Oh!

(engine buzzing)

- So the lock is only released
when the plane is on the ground.

(narrator): Investigators know
the pilots of Luxair Flight 9642

put their plane into Ground Mode
before landing,

but it doesn't explain why
the throttles were moved

further back to reverse,

while they were still hundreds
of feet in the air.

- It should be impossible to do.

- To get to that range
in flight, it's not supposed
to happen.

There's supposed to be
two things that prevent it
from happening.

(narrator): An electrical lock
prevents the power levers

from being moved into
reverse in flight.

Once the plane is on the ground

and the wheels are spinning at
at least 20 miles an hour,

a signal is sent
to an electrical switch

that releases the Flight Idle
Stop and allows the throttles

to move to the reverse position.

- This system is only meant
to be used on the ground,

and that's why they have
a lot of protections

to make that the only
possibility that's gonna happen.

- Could the lock have
somehow failed?

- The mechanical stop
is installed

so that the pilots can,
under no circumstances,

physically move the power levers

beyond Ground Idle,

so no reverse thrust possible.

(narrator): Investigators
study the components

that make up the locking system.

- The anti-skid system
checks out,

the wheel speed relays are fine,

and there's nothing wrong
with the lock switch.

(investigative music)

(narrator): Investigators also
check the anti-skid sensors

which measure wheel speed,

the computer that receives
those signals,

and the switch controlling
the lock.

- Everything seemed
to check out normally.

- It shouldn't unlock unless
the wheels are spinning.

So what went wrong?

(narrator):
Investigators scrutinize

the electrical lock system
that should have prevented

Flight 9642 from going
into reverse.

- Anything in
the maintenance record?

- There's this.

(narrator):
They discover an incident

that happened 14 years earlier.

- "Power lever setting below
Flight Idle possible in flight."

Huh.

(narrator): In 1988,

the Flight Idle Stop
disengaged inadvertently

on another Fokker 50.

- So it's not as foolproof
as we thought.

- The system design was actually
well designed by Fokker.

But they knew the system
had a problem.

(narrator): When the landing
gear is lowered,

an electrical pulse could be
sent to activate

the plane's anti-skid
control unit.

That sends out
a false indication

that the plane is on the ground,

just enough to unlock
the Flight Idle Stop.

- This particular pulse in
the anti-skid control unit

could, in fact, allow
the power levers to go

back into the Beta range.

(engine buzzing)

(narrator): At the time,
Fokker said the chance

of an inadvertent unlocking
due to the glitch

was extremely unlikely.

- These three conditions must be
met for the stop to unlock:

Gear down, the left and right
gear locks releasing

at precisely the same instant,

and the power levers
below Flight Idle.

- A lot of components had
to line up

in very great precision
to make it happen,

the perfect storm of bad things
happening together.

- Could they have triggered
the glitch?

(narrator): Investigators return
to the voice recording

and flight data to determine if
a short-lived electrical anomaly

allowed the engines to go
into reverse while in flight.

- We know from the sound
analysis the click

that we heard on the CVR is
the Ground Range Selector
being lifted.

(clicking)

Approximately 30 seconds
before impact,

the captain moves his power
levers below Flight Idle.

- Okay, so condition one is met.

- The first officer lowers
the landing gear

13 seconds later and they unlock
at the exact same time.

- Now that the conditions
to trigger the glitch

have been met,
for the next 16 seconds,

the levers can be
moved to reverse.

- The aircraft thinks
it's on the ground

and it will go into reverse
in flight.

- And just three seconds later,
the propellers go into reverse.

- That's it.

(jazzy investigative music)

- Ground Idle Stop off.

(narrator):
They believe that in an effort

to lose altitude quickly,

the pilots of Flight 9642
unknowingly triggered

the electrical anomaly that
allowed them to put

their engines into reverse.

The sequence of events begins

with the captain moving
the throttles

to Ground Mode to reduce
speed and altitude.

- I'm not sure that'll do it.

9642 continuing approach.

(narrator): The maneuver doesn't
have the desired effect.

The plane is still too high.

(Arendt): Flaps?
- Uh, we are flaps 10.

(narrator):
The crew extends the flaps

to reduce speed even further.

Then...

(clicking)

- Uh, gear down?
- Yeah.

(narrator): As Captain Poeckes
keeps his throttles

pulled as far back
as they can go,

the first officer lowers
the landing gear,

unaware it will trigger
the conditions

to unlock reverse.

(hubbub, whirring)

- The hell is that?!

Oh!

- There will be a loud bang.

Overall, everybody
will hear that

in the cockpit and in the cabin.

There will be an immense
increase in drag,

so you will literally feel
your body shifting and shaking.

(engines whistling)

(narrator):
Captain Poeckes doesn't even
realize what's happened.

- Pull, pull, pull, pull, pull!

Ah!
(GPWS): Terrain.

(horrified scream)
(GPWS): Terrain.

(Hildebrand):
Once the landing gear

was selected by
the first officer,

suddenly both engines
went into full reverse.

It was too late to recover.

(narrator):
25 seconds after the throttle

is inadvertently
moved to reverse,

the plane crashes,
resulting in 20 deaths.

(sorrowful piano music)

- If Fokker knew about this
anomaly in 1988,

why didn't they just fix it?

(narrator):
Investigators examine reports

to explain why Flight 9642

was allowed to fly despite
the aircraft manufacturer

knowing about a potential
glitch.

- They said the probability
of this happening

was so low that no immediate
action was required.

- It's a very short
duration power up,

so therefore the timing
has to be very precise

and the likelihood of it
happening was low,

there's no doubt about it,
but certainly it was not zero.

- They eventually came up
with a modification

and issued this service bulletin
about it a few years later.

(narrator): The manufacturer
of the skid control unit

had issued a service bulletin

suggesting a simple fix
that would prevent

the erroneous signal
from being sent.

(McNair): To modify
the anti-skid control unit

to the newer version that would
not provide this power up pulse,

one merely had to add a few
diodes and a capacitor,

so it wasn't a complicated fix.
It wasn't difficult to do.

It wasn't expensive.

(narrator):
But the notification was issued

as a Service Bulletin,

not an Airworthiness Directive

which would have made
the fix mandatory.

(Friesacher): If an aircraft
manufacturer is making

a modification to an aircraft,
it gives out a Service Bulletin.

You don't need to do it.

An Airworthiness Directive is
a state hazardous to the safety

of the operation of
the aircraft

that might even ground
the whole world fleet

of the aircraft
till it's modified.

(narrator): Luxair never
performed the suggested

1992 modification to its fleet
of Fokker aircraft.

- If it comes as
an Airworthiness Directive,

they would have complied,
no doubt about that.

And the problem would
have been fixed.

- The accident didn't
happen here.

It happens here

when they accepted an approach
they weren't prepared for.

- How much fuel will we need?

- Uh...

550...

We need 850 when
we leave the hold.

- No. We need fuel to reach
till our alternate

plus 20 minutes reserve,
so we'll still need 600 kilos.

- Yes, but I want to keep--

(controller): Luxair 9642,

descend to 3,000 feet on 1023,

turn left heading 130.

- Is that for us?
- Yes.

(narrator):
Investigators believe

that the main cause of
the crash of Flight 9642

was the crew's decision
to accept

the approach instruction rather
than join a holding pattern.

- Left heading 130, Luxair 9642.

What kind of crap is that?

(Friesacher): At the time
they got their first heading

for the intercept for
the localizer for the runway,

they should have said,

"No, we are not ready
for the approach."

(Krieger): Had they simply
rejected the approach

when the controller gave them
those additional headings

and descent down to 3,000 feet,

the controller would have
said that's fine.

- Here, they still don't
have the visibility

they need to land,
they're too high and too fast,

and still aren't properly
configured.

If ever there was a case
for a go-around.

- 9642 continuing approach.

(narrator): The investigators
also fault the crew

for not executing
a missed approach

when they had so much
going against them.

(Hildebrand): Once the crew
was surprised

by the ATC clearance
to start the approach

as number one,
a lot of events started,

putting the pilots in a kind
of a tunnel vision,

or into a continuation bias,

focusing only on the approach
and the landing,

without considering
any other options.

(narrator): To prevent the plane
from being put

into reverse in the air,
the team also recommends

that the modification
to the skid control box,

which stops any erroneous
signal,

be made mandatory for
all Fokker 50 airplanes.

Luxair makes the modification

to its entire fleet
of Fokker aircraft.

- The accident, in fact,
proves the fact

it was that serious and should
have been addressed.

(narrator):
Captain Poeckes was charged

with involuntary manslaughter.

He was fined and sentenced

to three-and-a-half years'
probation.

- The lessons we have learned
from this tragic Luxair accident

is always stick to standard
operating procedures.

Stick to the aircraft's
limitations.

Be aware of operational
bulletins.

Unfortunately, most of these
things were not done

by the Luxair crew and this led
to this tragic accident.

Subtitling: difuze