All language subtitles for Mayday.S03E07.Helicopter.Down.1080p.AMZN.WEB-DL.DD+2.0.H.264-playWEB_track3_[eng]

A thousand metres
above the frigid North Sea,
disaster strikes.

A helicopter is crippled
in the middle of a sudden
storm.

The pilots struggle for control
as it sinks helplessly
towards the sea.

They're far from land,
off the radar screens;

no one knows
exactly where they are.

In the days that follow,

investigators search
for the truth
hidden in this tangled wreck.

The cause of the crash shocks
those involved,

and reveals a hidden danger
that reaches far beyond
the North Sea.

- 3,000?
- We're not getting any oxygen!

- We have the terrain alarm.
- Aero Peru 603...

We are in an emergency.

The need for oil drives men
to some of the most unpleasant
places on Earth.

This is one of them.

The North Sea divides Britain
from mainland Europe.

It's a shallow sea
and the cruel winds
that race across it

can whip up enormous waves.

The sea is cold,
grey and violent.

But there's oil out here,

and so dozens
of drilling platforms
and thousands of men

must face whatever the weather
throws at them.

The only efficient way
to get the men out there
is by helicopter.

The flights are rough and long,
up to 500 kilometres each way.

After years, the trip
has become largely routine,

the danger below
forgotten by many.

What was that?

But on a cold January morning
in 1995,

18 men flying over the North Sea
were faced
with a horrible question.

Mayday! Mayday! Mayday!
Tail-rotor failure! Ditching!

Could they survive
in this extremely hostile
environment?

Oh, God! Ah!

January 19, 1995.

Commander Ced Roberts
and First Officer Lionel Sole

work for Bristow Helicopters
in Aberdeen, Scotland.

Their job is to ferry oil
workers out to the oil
platforms in the North Sea.

By mid-morning,
they've completed one trip
already,

and are getting ready
to head back out.

Their helicopter
is Super Puma 56 Charlie.

While it's being checked out
and refuelled,

Flight Officer Sole checks
the flight logs,

and Commander Roberts goes
through the weather reports,

which are updated
every two hours.

Oh, weather's okay.
Good for January.

This is where they're heading:
The North Sea.

The discovery of oil here
in the 1960s

was a shot in the arm
for the British economy.

Brent Crude,
as the oil is known,

is a light, sweet crude,
ideal for turning into
gasoline,

and its price is a benchmark
on the international oil
market.

It helped turn Aberdeen,
the Scottish port city
closest to the oil rigs,

into a boom town,
the European oil capital.

All the leading oil companies
have offices here.

The city is focused on
getting the black gold ashore.

Because the rigs
are so far offshore,

and the weather
so unpredictable,

helicopters are the only way
to reliably ferry workers
back and forth.

Hundreds of thousands of people
make the trip every year.

The Super Pumas
are one of the workhorses
of the North Sea oil industry.

Used around the world
by industry and military,

they're durable, tough,
and made to withstand
the elements.

There are more
of these helicopters flying
offshore here

than anywhere else in the world.

The passengers heading
to the platforms today

gather in the heliport's
departure lounge.

They all work
for the Texas company
Marathon Oil.

The North Sea has scores
of oilfields.

They are divided up
between several countries,
including England and Norway.

The governments then sell
the rights to drill
to a variety of oil companies.

Marathon operates
three platforms

in the so-called Brae Field,
Brae East, Bravo and Alpha.

North Sea oil platforms
are like cities
that never sleep.

They stand on the seabed,
held up by enormous legs
of either metal or concrete.

Below each one,
pipes snake out to the seabed.

Some straight down,

others fanning out at an angle
for up to several kilometres.

The same platform
may be extracting both oil
and natural gas

at the same time.

Out here, you're surrounded
by the sea with nowhere to go.

The weather is often horrible.

And the work on a rig
can be rough,
dirty and dangerous.

It's difficult to find
and retain the skilled workers

needed to pull the oil
from the sea.

So the platforms are built
to keep the workers happy.

Movies, internet cafes,
gym equipment,

even great food,

are all provided by management
to ensure the men
are entertained.

During 12-hour shifts,
workers handle heavy equipment.

And deal with great heights...

...or great depths.

But there are strict rules, too.

To protect the safety
of everyone onboard,

there's no drinking and smoking
is severely restricted.

Mayday! Explosion or fire
on the pipe or platform.

All personnel abandon.

One of Britain's
worst disasters happened
in the North Sea oilfields.

In 1988,
on Occidental Petroleum's
Piper Alpha platform,

the gas exploded
and set fire to oil.

167 men died...

The potential for disaster
is never very far away.

But on this January day,
the Marathon Oil workers
prepare as they always do.

All 16 are scheduled
to spend two weeks
on Marathon's Alpha platform,

followed by two weeks off.

To these men, getting to work
has become routine.

But getting a ticket
on this flight

calls for something
a little out of the ordinary.

None of them is permitted
to board a helicopter without
first going through this:

helicopter
underwater-escape training.

Their lives may depend
on knowing how to get out

of a submerged helicopter
or oil rig,

and knowing what to do
once they find themselves
in the chilly North Sea.

Several accidents
over more than 20 years
have driven home the point.

Training may help
a worker survive.

Before they set off
on every flight,
they must watch the video:

How to Behave if There's
an Emergency on Your Flight.

They've seen it all
a thousand times.

In an emergency,
if time does not permit,

just tighten your lap strap
and brace for impact.

To exit through the windows,

pull the red tab
to completely remove
the rubber seal...

The passengers
fasten their survival suits.

Made of GORE-TEX,
these dry suits won't keep
them afloat,

but are supposed to keep
the water out if the workers
are thrown into the sea.

Their bright colours
are also designed
to make rescue easier.

The trip to the Brae Alpha
oil platform is 230 kilometres.

If all goes well,
it will take little more
than an hour.

Then, 120 miles out,
they'll reach an area
called the Gate.

That's where all the helicopters
split up
and go their separate ways

to the individual oil platforms.

Brae Alpha is about
40 kilometres from the Gate.

For part of the journey,

the radar operators at
Air Traffic Control in Aberdeen
won't be able to see them.

The reason why we lose
low-level radar coverage
out over the North Sea is,

in essence,
because the Earth is round.

As a helicopter's flying
outbound to an oil rig,

it's actually following
the curvature of the Earth.

But radar pulses travel
in straight lines,

which means that as they travel
further and further away,

a gap opens up between
the surface of the Earth
and the radar waves.

If an aircraft flies
into that gap,
then it'll disappear from radar.

In the case of Aberdeen,
a helicopter operating
at about 2,000 feet

will disappear into that gap
at about 80 miles.

It's a black hole,
which Super Puma 56 Charlie
is now entering.

The helicopter
and the 18 men onboard
are over halfway to the rigs.

And from this moment on,
no one knows exactly
where they are.

56 Charlie
is a Super Puma helicopter

serving the North Sea
oil platforms
off the coast of Britain.

It's halfway
through a long flight
carrying 16 passengers

to the Brae Alpha oil rig.

The crew is getting concerned
about what they see
on their weather radar.

The forecast called
for scattered clouds,

but the weather
is changing fast.

What do you think
about this cloud?

It's quite thin.

Yeah, but look.
We're getting some cumulus too.

It's quite small.
About 100 yards across?

- Yeah, but it's developing
a bit.
- Mm.

Cumulus are puffy white clouds
like balls of cotton wool.

They're beautiful to look at,
and usually harmless.

They only last
between five and 40 minutes.

But helicopter pilots prefer
to go above them if possible,

because the air inside and below
gets very bumpy.

- Let's try to climb above it.
Go to 5,000 feet.
- Right.

Oh, look.
There's a line of them.

All along the route,
exactly where we're going.

Hmm. Yeah, we're not gaining
anything by this.

- Let's drop back down
to 3,000 feet.
- Alright.

So far, the weather
is nothing to worry about.

But over the North Sea,
it can change suddenly.

This corner of Europe
is where the warm winds
from the Atlantic

meet the icy blasts
from the Arctic and Siberia.

The warm water vapour condenses
into clouds, cools, then sinks.

It creates strong winds,
pushing the huge masses around.

The friction caused
by this motion can make
the clouds electrically
charged,

and that electricity
can be released as lightning.

What starts out as a placid day
can end up in a violent storm.

It's now one hour
after takeoff,

and 56 Charlie is approaching
the Gate,

the point where helicopters
begin their descent
to the individual oil
platforms.

They're 25 miles
from their destination,

and the weather is starting
to get worse.

Brae Traffic, 56 Charlie,

120 miles on the 056 HMR.

They make contact
with Brae Traffic Watch,

located on one
of the oil platforms.

It handles all the comings
and goings of helicopters.

But Brae Traffic
doesn't have radar.

It too has to rely on the pilots
to tell them where they are.

Leaving 3,000 feet.
Would you take the flight watch?

Roger, 56 Charlie.
I have your flight watch.

Aberdeen information,
Bristow's 56 Charlie
at 120 miles.

Leaving 3,000 feet.
Brae has the flight watch.

Roger, 56 Charlie.
Continue with ferry traffic.

Quite suddenly,
the weather has changed.

Instead of the harmless
fluffy balls of cotton wool,

a line of dangerous
cumulonimbus clouds
is now blocking their path.

They rise up
like huge white mountains,
more than 10,000 metres,

far higher
than the chopper can fly.

Underneath,
they're dark and menacing.

Pilots try to avoid them
at all costs.

Inside, gusts of wind
can reach up to 100 km/h.

The turbulence
can make the flight unpleasant,

but that's only part
of the danger.

The cumulonimbus,
that's the granddaddy
of all clouds.

It stretches from round
about 1,000 feet at its base

all the way up
to 28-30,000 feet.

They are the most dangerous
clouds that you'll come across,

particularly small aircraft
like helicopters.

Within a cumulonimbus,
you're going to find
severe turbulence,

you're going to find ice
and find heavy rain,

and, of course,
you're going to find lightning.

Flying a helicopter,
that's not where you want to be.

Lightning is one
of the most powerful forces
of nature.

Around the Earth,
it strikes an average
of 100 times per second,

each strike with the power
of up to a billion volts.

Aircraft can't completely
avoid it.

On average,
every passenger jet will be hit
once a year by lightning.

But the design of the planes
helps prevent them
being badly damaged.

Their bodies are traditionally
made of aluminium,

which is a good conductor
of electricity.

The lightning passes harmlessly
along the fuselage
and exits from the tail.

Helicopters use the same type
of design to keep safe,

and helicopters need it
in the North Sea.

With such stormy weather
and so many helicopters,

lightning strikes
are inevitable.

As they begin their descent,

the Super Puma enters the line
of clouds that stands
in their path.

- Bits of cloud coming up here.
- It's okay.

It's still green.
Let's carry on through that.

Green on the weather radar
means there's rain,

but it's not heavy enough
to worry about.

What the pilot sees
is that it's simply
like a television screen,

and on that television screen
he has a map,

and overlaid on top of that map
is a series of banded colours.

If there's no rain,
he has a blank map;

if there's lots of rain
and it's heavy, he has lots
of red squares on that.

And that gives you an idea
of the intensity and location
of the rainfall.

On board 56 Charlie,
the weather gets more intense.

They begin to get pelted
by hail.

Hey, where'd this come from?

It's coming in
through the vent.

It's like being
inside a beanbag
swamped by polystyrene balls.

It's so thick.

How come the engines
are still running?

There can't be any air left
out there.
- No.

Now another problem.

We've got a hard-over
on the ice detector.

- It's probably an ice pellet
stuck in the probe.
- Right.

The helicopter
has an ice detector,

a probe outside the craft
which is supposed
to tell the pilots

whether there's ice
on the blades.

But they think
it's become jammed with ice
and is giving a false reading.

And then... disaster.

- Bloody hell!
- What was that?
- Lightning. I saw it.

This is bad.
There's something
very, very wrong with this.

We'll have to go down,
I'm afraid.

The helicopter
has been damaged,

but they don't know how badly.

The entire body is shaking
and vibrating.

The crew's first instinct
is to get down
to a lower altitude

in case the worst happens
and they fall out of the sky.

Mayday! Mayday! 56 Charlie.
Lightning strike.

Severe vibration.

Mayday! Mayday!

Forty kilometres away,

another helicopter
is about to leave
an oil platform.

Commander Brian Backhouse
is loading passengers
onto 56 Bravo,

and preparing to fly back
to Aberdeen.

That's everyone. All set.

Suddenly the Loading Officer
hears Lionel Sole's Mayday call
on his radio.

Mayday! Mayday!
56 Charlie. Lightning strike.

Hear that Mayday, 56 Charlie?!

Gentlemen, my apologies,
but we have to disembark you.

We have an airborne emergency
on a sister aircraft.

Backhouse hurriedly
unloads his passengers.

He intends to help if he can.

Meanwhile,
a gale is steadily building up,

with winds in excess
of 70 km/h.

The seas are mounting.

The crew of 56 Charlie
are struggling to keep control
of their crippled helicopter.

After the initial flash, though,
the situation hasn't got worse.

The Grampian Freedom
is a standby ship
positioned near the oil rigs

to give oil workers
a way to escape
if anything goes wrong.

Her skipper, John MacInnes,
hears the helicopter's
distress call.

We increased, uh,
the speed to full speed ahead.

Everybody was informed
about the vessel,

uh, and told to get ready,

uh, for survivors
to be taken aboard.

Back on the Bravo platform,

what was a routine flight
for Brian Backhouse is about
to become a rescue mission.

He intends to find
the stricken helicopter
and nurse it to safety.

If it crashes into the sea,
he'll direct rescue ships
to the spot.

But they're not sure
where to go.

Let's go to the Gate
and proceed from there.

At least they have
a starting point.

The Grampian Freedom
doesn't know where to go,
either.

They're getting
conflicting messages
about where 56 Charlie is.

The helicopter's tiny size
and the rough seas
make it hard to find.

On the damaged helicopter,
Commander Roberts briefs
the passengers.

Gentlemen,
you are obviously aware
of the severe vibration.

We've had a lightning strike.
So please, pull up your hoods,

zip up your suits and prepare
for a possible ditching.

Countless hours of training

is supposed to have prepared
all on board
for a moment like this.

In a real emergency,
how many will remember it?

1,200 feet.
We're still flying.

Let's try to make it
to Brae Alpha and land there.

Their destination,
the Brae Alpha platform,
is now only 11 kilometres away.

Three minutes have passed
since the explosion,

and things don't seem
to be getting any worse.

I'll just try
a few small inputs to make sure
everything's working.

Yes, we've got control in pitch.
We've got control in roll.

And we've got control in yaw.

Tail rotor!!!

The helicopter is beginning
to spin round,

a sure sign that something's
happened to the tail rotor.

The only thing the pilots can do
to stop the spinning

is to switch off
the main rotor blade.

- Power off!
- Engines off!

Ditching has become
inevitable.

56 Charlie is falling fast.

More than 600 metres a minute,

with the main rotor acting
like a kind of parachute,

the blades being turned
only by the air
that rushes through them.

Mayday! Mayday!
Tail-rotor failure. Ditching.

Brace for emergency landing.

At this speed,
they're about 40 seconds
from hitting the North Sea.

The other pilots in 56 Bravo
are searching in vain.

There's no sign of 56 Charlie
in the sky or in the water.

Then they hear
another distress call.

Mayday! Mayday!
Tail-rotor failure! Ditching!

Mayday, Mayday, Mayday.

Relaying for 56 Charlie.

We have a suspected
tail-rotor failure.
He is ditching.

Commander Backhouse
in 56 Bravo knows
that he is closest

to the stricken helicopter.

Everything depends on him.

But he's not equipped to locate
the distress beacon 56 Charlie
will use when it ditches.

All he can do is search
mile after mile of grey sea.

Back on the Grampian Freedom,

the crew begins searching
the sea, as well as the sky.

But they know 56 Bravo
can cover ground more quickly

than the enormous,
slow-moving ship.

They do what they can
and wait for better directions.

Floats! Floats!
I can't find the floats!

- I got it! I got it!
Just keep it at trim angle!
- Right.

The pilots of 56 Charlie
are about to attempt one of
the most difficult manoeuvres:

ditching,
or landing in the middle
of the heaving sea.

Floats under the helicopter
are meant to keep it
from sinking.

If they're deployed too soon
before touchdown,

the chopper may lose
what little stability it has,
and topple over.

Too late, and they won't
inflate completely.

Instead of riding the waves,
the helicopter will sink
below them.

There's no second chance.

They time it perfectly.

We're down.

Seems quite stable.

They've landed safely,
but no one knows
if they will stay afloat.

Helicopters are top-heavy,

and they fear it could keel over
and sink at any moment.

- Let's get outta here!
- Do the doors!

They need to get
the life rafts out,

inflate them
and board them quickly.

They fear that if the helicopter
rolls over,

it will trap them all inside.

- Lift that end!
- Hold the rope!

You go back
and help with the evacuation,
I'm gonna shut things down here.

I'm gonna try
one last mayday call.

But the evacuation
doesn't go smoothly.

When they throw out
one of the life rafts,

the strong wind blows it back
against the helicopter.

They can't get into it.
- We can't get this one down!
Can we go out the other side?

Better we all stay together
anyway!
Off you go! Go on, go on!

Go!
Mayday! Mayday!

56 Charlie.
We are on the water, floating,
manning the dinghy!

He doesn't mention
their position.

Make room, I said! Make room!

The raft is dangerously
overloaded.

There are 18 on board,
and it's only meant for 14.

Water is already up
to their ankles, and rising.

Once in the raft,
they have no way
of communicating where they
are.

For the first time,
the pilots are able to see
what caused the disaster.

The rear-rotor-blade assembly
and gearbox have broken off,

and are hanging down the side
of the helicopter,

held on
by just a couple of pipes.

No one realizes it yet,
but in the rush,

they've forgotten to bring
the distress beacon with them
from the helicopter.

It sends out a signal
that can be picked up
by rescuers.

Forgetting it could mean
the difference between life
and death.

Two ropes attach the life raft
to the helicopter.

They're meant to stop the raft
from drifting away,

but they'll also drag them down
if the helicopter sinks.

One of the passengers
has a knife.

- Shall I cut the line?!
- No, not yet!

We have a better chance
of being spotted if we're close
to the helicopter!

Problems mount.

The passengers are trying
to raise the canopy
to protect them,

but it gets stuck.

Without the canopy,
they're at the mercy
of the waves.

And then the helicopter itself
becomes a danger.

When the doors were jettisoned,

they were supposed to be
designed to slip down
into the water and sink.

Instead, one of them,
which has a jagged edge,

is floating on the surface
and is heading straight
for the raft.

The life raft has been punctured
by the floating door.

Come on, bail!
Bail with everything you got!
We're gonna sink!

No, don't worry about it!
We're not gonna sink!

We got double-layer rubber
tubes here filled with air!
It cannot sink!

One wave and we're under!

The pilots do their best
to put on a brave face.

There are other helicopters
and ships out there!
They know we're down!

They heard our mayday!

The overloaded life raft
is getting lower and lower
in the water.

Inside, it's already waist-deep.

Now the pounding waves
are pushing them
beneath the sharp edges

of the drooping
helicopter blades.

We need to get some distance!
We'll have to cut the line!

There are supposed to be
two safety lines connecting
the raft to the helicopter:

one short, one long.

But the long line is broken.

The long line's been cut!
It's been shredded!

You'll have to cut
the short one!

The short line
is the only thing attaching
them to the helicopter.

If they cut that,
they'll quickly drift away,

a tiny raft full of men
at the mercy of the sea.

But if they don't cut it,

the jagged edges
of the helicopter could tear
their life raft to shreds

and sink them all.

Eighteen people have
scrambled aboard a life raft

after their helicopter crashed
into the North Sea.

The raft is overloaded.

It's been punctured
by the jagged metal edges
of the helicopter door,

and is getting lower and lower
in the water.

They have to get away
from the helicopter.

Flight Officer Lionel Sole
takes the fateful decision
and cuts the rope.

They begin to drift away
into the storm.

The conditions are deadly.

Most of their survival suits
are leaking freezing water.

For a person in the water,
hypothermia can begin

when the temperatures of air
and water added together
is below 50 degrees centigrade.

In the North Sea in winter,
the temperature
is far below that.

Normal muscle
and brain functions
are quickly affected.

The core body temperature
will sink,

followed by unconsciousness
and death.

Their chances of rescue
are slim.

No one knows where they are.

Just a tiny dot
on a vast, turbulent sea.

Quiet, quiet!
I hear something!

There's a helicopter!

The men are desperate.

This could be their last chance.

Quickly!

Pass me those flares!
The flares in the pocket
behind you!

We need help!

Here! Here! We're over here!

But it's all in vain.

The helicopter passes by.

The men can't believe it.

Their only hope is gone.

On 56 Bravo, Brian Backhouse
can see only grey seas.

But suddenly,
his co-pilot spots something.

Contact, right, 2:00.

Okay. Roger.
Let's investigate.

Target, contact.
Target confirmed. 56 Charlie.

Standby for position report.

Like a guardian angel,

56 Bravo hovers directly above
the survivors for over an hour,

directing rescue boats
and aircraft towards
this tiny speck in the ocean.

He came in and hovered...
fairly close,

because he wanted to count
the number of people
onboard the life raft.

So for a while,
he was right over top of us
and blowing us around a bit.

But as soon as he had gotten
the information he wanted,
he backed off,

and he was just marking
the position
for the rescue craft to find us.

First to arrive
is the Grampian Freedom.

We had lookouts posted
all around the vessel,

some on top of the bridge,
on each wing at the bridge.

A helicopter came
and he started crossing our bow,

which is not our procedure
in that kind of situation.

Almost a mile away
from the raft,

the Grampian Freedom launches
its fast rescue boat.

The boat sets off at full speed
to the rescue.

The rain and the waves
make finding the raft
difficult.

- Hey, hey, hey, hey!
There's the boat!
- It's coming fast!

No, no, no! Don't stick us!

Relax, boys.
They know what they're doing.

Let's go! Quickly! Go!

The rescue boat throws
a lifeline to the stranded men,

and they begin
pulling themselves to safety.

But there's another challenge
their training
hasn't prepared them for.

We reached the, uh,
the standby boat.

And you're looking at the hull,
a huge steel hull,

you said,
"I'm never gonna get up there."

But the crews are well-trained.

They wait for the swells
to go up and down
at the right motions.

And they have a large net
hanging down the side
of the boat,

and they said,
"We're gonna come alongside,

we'll be on top of the wave
and when we shout 'jump,'
you jump and grab the net.

Don't look back,
'cause we'll be gone."

We came alongside,
high up on the wave,
grabbed the net,

the wave went back down,
they were away
and they pulled off,

and we just climbed
the last few feet over the side,
onto the Grampian Freedom.

Later that day,

a rescue helicopter winches
up 14 of the survivors

and flies them back to Aberdeen.

Four of the men, however,
never want to travel
in a helicopter again,

so they refuse to leave
the Grampian Freedom.

They're in for ever more misery.

They're buffeted
by a force-10 gale

the whole of their long journey
back to Aberdeen.

Through their skill
and against all the odds,

Cedric Roberts and Lionel Sole
have saved the lives
of all onboard.

I must admit, at the time,
I did think that was it,
we were gonna die.

The whole world had changed
from being really good

to being what I thought
was a complete disaster
at that time.

It was the worst situation
I've ever been in, in the air,

and I was very worried
that was gonna be it.

But the day
after the accident,
they came under suspicion.

Their report of what happened
starts being questioned.

Lightning,
notionally at least,

should not affect
a very powerful North Sea
helicopter.

This is the first time
I can recall a lightning strike

having ended up
with this kind of conclusion.

The experts are skeptical
of the pilots' story.

No other helicopter
is known to have crashed
into the North Sea

because of lightning.

Perhaps there had been
some mechanical failure.

There are even whispers
of pilot error,

of recklessly flying
into storm clouds.

The evidence
to support their story

was now beneath the waves
with 56 Charlie.

The Air Accident
Investigation Branch,

Britain's air-crash detectives,
begin searching for the truth.

It may look like a rig,
but the Stadive
is actually a ship,

mostly used for servicing
oil platforms.

It has nine powerful engines
which keep it stable
in almost any weather.

And it carries
miniature submarines
for underwater exploration.

A day after the accident,
it's brought in to find
and raise the missing
helicopter

from the bottom
of the North Sea.

The investigation gets off
to a good start.

Within a day,
the television cameras onboard
the Stadive's two submersibles

locate what's left
of 56 Charlie on the seabed.

But raising it
is a different matter.

They carry on working
into the night.

Soon, several pieces
of 56 Charlie
have been recovered,

but still not the vital clue:
the missing tail rotor.

Ed Trimble was the AAIB's
lead investigator.

But the big problem
was to recover
the tail-rotor assembly.

Without that, the investigation
was literally going nowhere.

We knew
that the tail-rotor assembly,

uh, had been dangling
over the side of the pylon
as the helicopter had ditched,

and therefore had detached
at some point

between the ditching
and where we had caught up
with the main wreckage.

Keeping the Stadive going
would cost another
£20,000 a day.

Ed Trimble rang his boss.

He was fairly skeptical
of our chances.

Uh, he asked what I thought
our chances were of finding the,
uh, tail rotor, and I,

being an eternal optimist,
said, "80%,"
to which he replied:

"I think you'd be very lucky
if you had a 10% chance

of recovering the tail-rotor
assembly in the North Sea."

Ed Trimble stays up all night,

relentlessly monitoring
the underwater cameras.

I didn't want to be
in a situation

where we would've missed
any evidence of further wreckage
in a particular...

any parts
of the tail-rotor assembly.

Go get yourself a coffee,
Eddie.

By the time, uh,
8:00 was looming,

I decided to go down
to the galley to get a coffee.

And I couldn't have been away
any more than maximum
seven to 10 minutes

when I suddenly heard these...

tremendously excited shouts
from our team.

I did it! Yes! Eureka!
We found it!

- Hold position!
- As I walked in, I ran in,

there, smack in the middle
of the screen,

was the whole
of the tail-rotor assembly.

And even at the first glance,

I could see that one
of the tail-rotor blades
showed clear evidence

of a lightning strike.

The crew was right.

The submarine's cameras
reveal telltale burn marks
on the tail-rotor blade.

A close look at the wreckage
on the deck reveals

that two of the main rotor
blades were also struck
by lightning.

But it's this tail rotor
that suffered the most damage.

Since lightning is not known
to have forced a helicopter to
crash into the North Sea
before,

the question is: Why now?

Ed Trimble called in
lightning expert John Hardwick

to discover just what had hit
56 Charlie.

What we wanted to do
with this set of tests

was to take a set
of tail-rotor blades
from the Super Puma helicopter

and subject them
to varying energy levels
of simulated lightning strikes.

The lightning objectives
at Culham

basically were to try
and reproduce

the degree of lightning damage,

in order to identify
what kind of level of energy
was associated

with this particular strike.

This home video of the tests
was taken by Ed Trimble.

Representatives of the company
that makes the Super Puma
were there too.

Hardwick ran the blade through
several lightning strikes

until he was able
to reproduce the damage
found on the rotor blade.

To do it, he had to generate
a simulated strike
of enormous power.

Something far more dangerous
than anyone thought the
helicopter would be exposed to.

Something that wasn't supposed
to happen over the North Sea.

There've been a few incidents
over the years.

Minor strikes,
a little bit of damage
to the helicopter.

But we never expected
anything as severe
as happened on that day.

For one brief instant,
it was more
than all the electrical power

being consumed
in the entire United States.

Some 30-billion watts.

And this enormous flash
of lightning had happened
over the North Sea,

where, each year,

almost three-million passengers
fly unsuspecting
to the oil platforms.

The helicopters we fly
are certified
to the highest standards.

It's the same as you'd get
on a major airline
that's flying transatlantic.

So we had no reason to believe
that any lightning
that we encountered

would do any severe damage
to the helicopter.

Ordinary lightning wouldn't.

But this wasn't ordinary.

A lightning strike generates
a huge pulse of energy.

We can detect
these pulses of energy

via multiple transmitters
and receivers that are situated
throughout Europe.

The information
is calibrated locally,

and once the position
has been triangulated,

that's passed to the Met Office
in London.

When the records
were examined,

they showed something
very peculiar.

This is what they think
happened.

Inside cumulonimbus clouds,

tiny ice crystals
are swept upwards
by the wind currents.

At the top of the cloud,
where it's much colder,

they combine with other crystals
to form hail.

The hail, being heavy,
plummets back to Earth.

On the way down, it hits
the rising water crystals,
causing friction.

The crystals become
electrically charged.

On that particular day,

there was very little indication
that there was any significance
in these clouds.

We're flying along,
everything just seemed
very normal.

We went through what seemed
to us,

by comparison
to what was around that day,
a fairly small cloud.

But there was suddenly
a lot of snow and ice pellets
in the air.

I've never seen as much
in the way of soft hail pellets
in my whole flying career.

And the worrying thing
was that immediately we knew

that obviously
there was a lot...

a high level of energy
in that cloud

to produce that amount
of soft hail,

which also meant
there was a high chance
of there being lightning there,

but by that time
it was too late.

When a helicopter
enters the cloud,

the sharp tips
of its whirling rotor blades
cut through these crystals,

causing more friction,
more electricity,

until it's all released
in a blinding flash.

The records show that the flash
which hit 56 Charlie

had been the only one recorded
over the North Sea that day,

caused almost certainly
by the helicopter itself.

However, for some reason,
nearly all the damage had been
confined to the tail rotor.

What was it about the tail rotor
that had made it
especially vulnerable?

Then Ed Trimble made
a remarkable discovery.

When the Civil Aviation
Authorities certified
the Super Puma as safe,

they had missed something
important,

something which may have caused
56 Charlie to fall from the
sky.

Safety investigators examine
the wreckage of a helicopter

which crash-landed
in the North Sea.

As they study
the ruined aircraft
more closely,

they uncover the cause
of the accident.

When the British Civil Aviation
Authority laid down
the lightning safety standards,

they were looking
at fibreglass blades,

then the normal material
for helicopter rotors.

But in the 1980s,
plane-makers began using
the new composite materials,

like carbon fibre,
which were lighter and
stronger.

In particular, they began
making the rotor blades

out of carbon fibre
instead of fibreglass.

It was assumed
that the same standards would
apply equally to the new
blades.

In the industry,
that's known as "read across,"
and it's very dangerous.

In fact, it was the very design
of these composite blades
which brought down 56 Charlie.

Although made of carbon fibre,

composite blades have
a metal anti-erosion strip
glued on to protect the edge.

That's where the trouble starts.

Carbon is a conductor
of electricity,

but it's a thousand times worse
than aluminium,

so you get a thousand times
as much heat produced.

The carbon blade
gets very, very hot.

And when the current meets
the metal strip
running along the edge...

...there is furious arcing
and sparking,

until finally part
of the erosion strip explodes.

As little as 100 grams
of the erosion strip flew off,

but it was enough.

Without its weight,
the rear rotor was unbalanced.

That's what caused the vibration
felt onboard 56 Charlie

immediately after
the lightning strike.

Three minutes later,
when Lionel Sole tested out
the controls,

the unbalanced blades
put the tail rotor
under enormous stress.

The bolts holding it on snapped.

- We've lost the tail rotor!
- Tail rotor's gone!

It was like a blowout
in a car, only much, much worse.

Things, at that point...

were really very, very worrying.

Uh, we both knew
what had happened.
We'd lost the tail rotor.

And if you don't do exactly
the right thing at that point,

your life expectancy
is very short, it's seconds.
We had to do the right thing.

We managed to point it into wind
and there was quite a big sea
building up.

And at 100 feet,
I pull back on the stick
to flare the helicopter...

...slow down
its rate of descent,

and we were very fortunate
at that point - a nice,
friendly wave came along -

and as I levelled
the helicopter,
the wave came up,

we sat on the top of it
and went down.

It was one of the best landings
I've ever done,

but that was luck
more than judgment.

As bad as it was,
it could've been worse.

The two hydraulic pipes
connecting the assembly
to the helicopter did not
break.

These two small-diameter pipes
had held

the mass of the gearbox
and tail-rotor assembly

dangling over the right side
of the pylon.

Without the weight
of the rotor assembly,

the helicopter would've
tipped forward.

Had that tail-rotor gearbox
and tail-rotor assembly

completely separated
from the helicopter,

then all 18 lives
would've been lost,

because the helicopter would've
pitched down irrecoverably

and gone into the North Sea.

The investigators found
the answer to the mystery
of a helicopter crash,

but they stumbled across
a bigger problem.

One that affects
every air traveller.

Investigators believe
that 56 Charlie's violent end

was caused
by a savage lightning strike

greater than anything
it was built to withstand.

And when the lightning hit,

it exposed a problem
in the carbon-fibre blades
that made them vulnerable.

The tremendous heat created
where the carbon fibre met
the metal erosion strip

could occur again.

And the same type
of violent reaction
could hypothetically take place

in any aircraft
that has carbon fibre
mixed with other materials.

Increasingly,
aluminium is being replaced
with carbon fibre.

The world's largest plane,
the A380 Airbus, for instance,
has over 20%.

What will happen
if these planes encounter
a monster lightning strike?

This was the investigators'
biggest concern arising
out of this Super Puma
accident.

The findings were unexpected,

and treated
with some skepticism.

Though the tests indicated
that an unexpectedly large
lightning strike hit 56
Charlie,

Britain's Civil Aviation
Authority refused to accept it.

No action was taken to increase
the safety standards

that these helicopters
must meet.

I thought
that the reaction was poor.

There seemed to be, uh,
a real reluctance...

on their behalf
to accept the evidence.

If Britain's
air-crash detectives are right,

there is a real concern
facing air travellers.

Flashes of lightning far greater
than aircraft are supposed
to encounter are possible,

and aircraft made
of newer composite materials
are at increased risk.

For the Super Puma, though,
the lessons have been learned.

The design of the rotor blades
has been vastly strengthened.

The erosion strips
are now secured
with heavy bolts.

And the pilots have been
instructed to give storm clouds
a wider berth.

The men who must fly
these machines to work are
prepared to accept the risks.

Well, I think the morning
that we ditched,

we were very, very fortunate,

because the outcome
could've gone horribly wrong.

But we survived. We got home.

My feelings that morning was:
This could never happen to me.

Now when I fly in a chopper,
especially in wintertime,

if it's gonna be buffeted about
in the wind,

I sometimes get
in the back of my mind:
This can't happen to me again.

But we've all a choice.
We've all a choice
either to stop or we carry on.

And I'm still there
25 years later,
still earning a living.

The crash of 56 Charlie
was a hair-raising incident

that could so easily have ended
in tragedy.

In the winter of 1995,

the skill
of Commander Ced Roberts
and Flight Officer Lionel Sole

saved the lives
of their 16 passengers.

Roberts and Sole receive
an award for their work.

The Guild of Air Pilots
and Air Navigators recognized
their skill and bravery

in the emergency landing.

Although we received a number
of awards after the, uh,

the incident, um,
from various organizations,

one thing I received,
which is far more precious to me
than any of them,

was from the daughters
of one of my passengers.

It was this little card.
It says, "Dear Captain Roberts,

I can't tell you
how much I need to thank you
after you saved my dad's life.

It took a lot of effort
to try to keep calm
while you were falling.

If you hadn't have got
that helicopter in control,

my dad maybe
wouldn't be here today.

Thank you very, very,
very much."

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