Original subtitles

A 747 flying toward South Africa

fills with smoke.

A fire has erupted in the cargo area,

but the plane can't land.

It's too far over the Indian Ocean.

The first thought I think for many, many South Africans

was what was on that plane?

The passengers are choking on toxic fumes.

Request a full emergency, please.

Affirmative, that's Charlie, Charlie.

There's only one way to clear the smoke.

The crew must try a rarely used and risky maneuver.

Open the doors!

Open the doors in flight.

Springbok 295. Plaisance.

It's a race against time as the plane burns up.

It must reach land before it crashes into the sea.

Springbok 295. Plaisance.

Mayday, mayday.

On November 27th, 1987,

a South African Airways 747 flies from Taiwan back home to South Africa.

- Everything good? - Fine, Captain.

- Ready to take over? - Yes, thanks.

Nine hours into their flight over the Indian Ocean,

the main crew returns to their seats,

allowing the relief crew to rest.

The crew prepares for a scheduled stop on the island of Mauritius.

Valerie Lottering has enjoyed her first overseas vacation,

joining her husband Corrie while he was on business.

My father was on a business trip

and my mum had gone with for a holiday.

My dad had actually gone to the east to secure

cell phone technology,

which was just sort of happening in South Africa at the time.

The plane is a modified 747,

known as a Combi, short for combination.

A passenger plane and a cargo plane in one,

it's designed to accommodate flexible quantities of passengers and cargo.

The Combi has a large cargo area down below, like a regular 747.

The Combi also has a large cargo area

right behind the last row of economy class seats.

The cockpit sits one level above the cabin.

You could load from six to 12 pallets on the main deck,

adjusting the bulk head

for the number of passengers you wanted to carry.

And this turned out to be

a very worthwhile and useful tool.

Flight 295 is carrying 159 people,

as well as six large pallets of cargo.

Known as the Helderberg, the 747 Combi is a vital member

of the South African Airways fleet.

It's particularly useful for long range flying.

For South African Airways

during the days of Apartheid,

a plane like the Combi helped them in that respect,

because they had to fly around the bulge of Africa over the Atlantic.

To protest South Africa's white racist regime,

the vast majority of black African states refused to allow

South African Airlines to fly over their airspace,

causing them to fly longer routes.

There were sanctions, heavy sanctions against South Africa

on political, economic, and cultural fronts.

South Africa was not welcome

anywhere credible in the world.

On Flight 295,

less than an hour before its stop in Mauritius,

the smoke alarm breaks the calm of the cockpit.

It's for the cargo area on the main deck,

directly behind the passengers.

By the time the crew gets to it the fire is raging.

It's bad.

- Should I get another bottle over there? - Yeah, hurry!

Read out the fire checklist for us, please.

In fire emergencies, the crew follows

a standard checklist to extinguish the fire.

- The breaker popped as well. - Huh?

We'll check the breaker panel as well.

The fire is burning through the plane's wiring,

causing short circuits.

Move as far forward as you can.

But there's a more immediate problem.

Passengers are having trouble breathing.

Duct isolation valve switches open.

Pack valve switches all open.

Recirculating fan switches...

off.

The fire checklist instructs the pilot to land at the nearest airport.

But the closest one is on the island of Mauritius,

still more than 300 kilometers away.

There's not a lot Captain Uys can do.

He asks a member of his flight crew

to help fight the cargo fire.

Bring me another bottle.

Captain Uys initiates an emergency descent.

He calls the airport on the island of Mauritius,

which is on good terms with South Africa.

It's just before 4:00 in the morning

when Mauritius Air Traffic Control receives the call.

Mauritius, Mauritius, Springbok two-niner-five.

Springbok two niner five, Mauritius, good morning. Go ahead.

Good morning. We have a smoke problem

and we're doing emergency descent

to level 15... uh, 140.

Confirm you wish to descend to level 140.

Yeah, we've already commenced

due to a smoke problem in the airplane.

Do you request a full emergency, please?

Affirmative. That's Charlie, Charlie!

Captain Uys sounds calm,

but he has to find a way

of getting rid of the smoke on his plane.

Whatever is burning in the cargo hold is producing

thick, noxious smoke which is pouring into the cabin.

It could be deadly to the passengers.

Your actual position, please.

Ah, say again?

Actual position.

Captain Uys is losing power to many of his instruments.

We've lost a lot of electrics.

We haven't got anything on the, uh, on the aircraft now.

He's not sure where he is.

The airport prepares for an emergency landing,

while the crew of the Helderberg follows instructions

from another checklist to get rid of the smoke.

Supplementary vent fan switch off.

Recirculating fan switches...

on.

Smoke condition?

Hold on, I'll check downstairs.

The crew gets more bad news from the cabin.

The smoke is getting thicker.

It's worse!

We can't breathe down here.

With the plane approaching

an altitude of 4,500 meters,

the checklist advises the captain to execute

an emergency maneuver that few pilots have

ever performed.

We need to open the doors.

Repeat, open the doors!

Opening the plane's doors in midair

is the only hope for thinning a cloud of smoke

that could kill the passengers

before the struggling jet can land.

As the cabin of South African Airways Flight 295 fills with smoke,

there's only one way to save the passengers from the lethal fumes.

Outer flight level 150 for 140.

150 for 140.

150...

The captain begins his emergency descent

to 4,500 meters, so the doors can be opened.

At 4,500 meters, passengers can breathe the outside air.

At that altitude, the difference in pressure

between the air inside and outside the cabin is enough

to force the cabin air out quickly,

but not dangerously.

Now the captain must dramatically reduce his airspeed

to 370 kilometers an hour, 200 knots.

Any faster and the crew won't be able to open the doors.

This is Captain Uys speaking.

We're opening two of the entry doors

to clear the smoke from the cabin.

Do not panic, you'll be much more comfortable

once we complete this procedure.

You just crack the door and this generates

a tremendous amount of airflow through the airplane.

Plaisance Springbok 2-9-5.

We've opened the doors to see if we can...

We should be okay.

Look there!

Close the bloody door!

Joe, switch up quickly,

then close the hole on your side.

Smoke is now building in the cockpit,

but there's no outside door to open.

Temperature is 22.22,

and the QNH is 1018 hectopascals,

one-zero-one-eight over.

The air-traffic controller now focuses

on giving the captain the information he needs for an emergency landing.

Roger, one-zero-one-eight.

Affirmative, and both runways are available if you wish.

And 295, I request pilot's intention.

We'd like to check in on 1-3.

Confirm runway 1-3.

Charlie, Charlie.

Affirmative. You're cleared direct

to Foxtrot Foxtrot. You report approaching 5-0.

Okay.

Captain Uys has one hope.

He must make it to the island of Mauritius 265 kilometers away.

The Helderberg continues on its desperate journey.

295, Plaisance.

But at 4:08 in the morning,

a call by the air-traffic controller is not returned.

Springbok 295, Plaisance.

Springbok 295, Plaisance?

With no response from Flight 295 for 36 minutes,

Air Traffic Control Mauritius formally declares an emergency.

An alert goes out to search-and-rescue crews.

Several aircraft take off from Mauritius

and search the dark waters for the missing plane,

but find nothing.

At the airport in Johannesburg,

South African Airways officially declares

Flight 295 "delayed."

We were supposed to be going away on our annual holiday,

so we were all very excited, 'cause from picking them up,

my parents up from the airport,

we were supposed to go off to three week holiday.

I think that's maybe the, the extent of the...

differences of, of the emotions is

that you're so anxious and excited

for them to come home,

and then the absolute devastation

of the news, getting the news,

you know, that the aircraft has gone missing.

In the afternoon of the next day,

a rescue plane spots the first signs

of floating aircraft wreckage.

Rennie Van Zyl, the head of South Africa's Aviation Safety Board is

assigned to the Helderberg case.

A normal investigator will only handle a major accident

about once in 20 years, in his career.

So this was a... quite a big... wake up

and a challenge to us,

to start running with this investigation in that morning.

Eight bodies are found in the water,

all suffering from extreme trauma.

It was around about two o'clock

that we in fact were advised that the wreckage

and an oil slick had been spotted.

And it was then quite apparent that the airplane was lost.

The most astonishing thing is

that my parents had actually, the night before they had flown,

had sorted out their wills, had sorted out their insurances,

had sorted out all of their documentation

and paperwork before they flew.

Which was quite amazing.

My father made

very, very close family friends of ours our guardians,

our godparents, and we were to live with them.

South Africa quickly becomes obsessed

with what caused the crash.

In the early days, there's very little to examine,

only small bits of the plane

that are floating on the surface.

Contained within that debris,

Rennie Van Zyl's team discovers three wristwatches.

The watches give them a probable time of impact.

These wristwatches were in fact part of the baggage,

and when examined we were able

to find that the one had stopped

and two others were still running,

and the two running ones were the exact Taiwanese time.

The stopped one did give us the minute indication

of what we could establish

as the impact time of the airplane.

The impact time is only three minutes

after the last communication with the plane.

The Helderberg's demise was sudden and dramatic.

In the press and in public opinion,

it reinforces the idea that something sinister brought the plane down.

In the years leading up to the crash,

South African Airways offices around the world had been the target of protests.

The South African Airways Airline at that particular time was a government body.

It was owned by the government.

It was the national carrier,

but it was also very much perceived

to be a part of the South African government.

So another aspect of this plane crash,

and another theory that was put around

was that there could have been a bomb in the cargo.

That in fact we were a target, South Africa,

or this SAA plane was a target of terrorists

who had the worst interests of this country at heart.

Experts examine the small bits of wreckage they have,

searching for the telltale signs of an explosion.

Impact cavities, surface pitting,

or spatter cavities.

Spatter cavities are caused by the white hot fragments from a high explosive device,

striking and melting the light alloys of the aircraft structure.

But experts spot no sign of an explosion.

And when air-traffic-control tapes are studied,

Van Zyl hears that the crew appeared

to be coping with the emergency.

Plaisance Springbok 295, we've opened the doors

to see it we can... We should be okay.

We've had rumors of atomic bombs,

for example, in there,

but that won't cause the airplane to burn.

It will take out the airplane.

We did not have that same experience here.

This airplane flew for 22 minutes.

It's out of the ordinary circumstances.

This was not an explosion that took out the airplane.

With just small pieces of the plane to study,

investigators are stumped.

They don't know what caused the fire,

or what role it played in the destruction of the plane.

The obvious thing to do was to go and try and retrieve

the cockpit voice recorder, flight data recorder

and as much wreckage as we can from the aircraft

to establish what really had happened.

The problem is Van Zyl doesn't even know

where to find the underwater wreckage.

It could be far from the floating debris.

No one is sure exactly where the plane crashed.

He turns to the United States looking for help.

An American salvage company is hired to find the wreckage

and black boxes, but time is running out.

The boxes have built-in locating devices called pingers,

which run on batteries and will eventually run down.

The driving factor was that the pinger on

the data and voice recorders was transmitting,

and it only had a 30-day guaranteed shelf life.

If we couldn't get out there in 30 days,

the chances were that we wouldn't be able to detect it.

By the time the proper equipment can be

assembled in the Indian Ocean,

only seven days remain

before the batteries in the pingers will die out.

Meanwhile blood tests are performed on the human remains pulled from the debris field.

All show traces of soot in their trachea.

It's determined that at least two of the passengers

died from smoke inhalation.

Investigators face a disturbing realization.

Even as the crew was struggling to land their plane,

some of the passengers were already dead.

While searching for the black boxes,

investigators continue to examine the floating wreckage.

Amongst the hundreds of recovered items,

a partly-melted graphite tennis racket offers a telltale clue about the fire.

Graphite only burns at temperatures greater than 600 degrees Celsius.

Investigators now know that the fire on theHelderberg was extremely hot.

This discovery may explain why a fully-charged extinguisher from the front of the plane is

recovered with other floating wreckage.

Investigators notice a melted piece of cargo netting

on the outside of the extinguisher.

They determine that the extinguisher is from the passenger cabin,

suggesting that as the fire burned,

a crew member grabbed the extinguisher

and brought it to the cargo area.

A full fire extinguisher

in a plane that was brought down by a fire shows

that for whatever reason it wasn't discharged,

because the crewmember couldn't access the area because of the heat,

or the fact that there was melted metal

on the fire extinguisher is further evidence to the intensity of the fire.

Before this accident,

in the 20-year history of the 747 Combi,

no one had ever died from fire or smoke.

When we heard about a fire in the Helderberg,

this was the first time for a wide-body airplane.

It was... it was news. And because it was so new

and the thought was that we really couldn't have anything like that.

What could have caused such an intense fire on the Helderberg?

Was it a wiring problem on the plane,

or had the cargo itself somehow started the blaze?

Initially, the investigation focused on, "What was the cargo?"

The fire obviously had originated

in the main deck cargo compartment,

so the logical thing is to look

what did the waybills indicate was carried in the airplane.

Investigators learn that there were six pallets of cargo on board Flight 295.

Using master waybills, Van Zyl's team is

able to determine that 47,000 kilograms

of baggage and cargo was officially on board.

Investigators discover that before takeoff,

a Taiwanese customs official performed a random inspection

of some of the cargo. He found nothing suspicious.

More than ever, investigators need

to find the rest of the plane,

and locate the Helderberg's black boxes.

But 30 days after the crash,

Van Zyl's team gets some very bad news.

There's still no signal detected from the black boxes.

And they are still not certain

exactly where the majority of the wreckage is.

So far, the search has cost 1.5 million US dollars,

and the team has been unable to locate vital evidence.

The Helderberg crash is quickly becoming a test

of Van Zyl's abilities and his resolve.

The investigation reaches a stand still.

Van Zyl has failed to discover the cause of the fire

or even find the plane's wreckage.

If he keeps looking, it will cost millions more,

and the chances of success are getting increasingly remote.

This wasn't just an airplane, this was a Boeing 747.

It was the largest airplane of its type.

And this was a 747 of South Africa's national airlines.

Hundreds of thousands of people who flew the 747 every day

at that time were dependent on a satisfactory answer

as to whether or not this aircraft was safe,

and whether or not there were any structural

or design deficiencies in the airplane.

So the stakes for us were quite large,

and the stakes for Mr. Van Zyl as the head

of the South African investigation were enormous.

It would have been very, very easy

for the South African government to say,

"The water's too deep, it's too far from Mauritius,

"we cannot investigate this accident."

Well beneath the gray waves of the Indian Ocean,

the wreckage of the Helderberg remains hidden.

Now one man, Rennie Van Zyl, must decide whether to spend

the money needed to recover the plane's wreckage.

But almost two months after the Helderberg slammed into the Indian Ocean,

no one even knows the precise location of the main wreckage.

Van Zyl decides he must try to recover what he can.

Without the wreckage, we'll never know the truth.

So they spent on one investigation

what we spent in six months of conducting

all of our investigations in the United States.

Before investigators can salvage the Helderberg,

they must find it.

The wreckage lies somewhere very deep underwater.

Sixty-one days after the crash of the Helderberg,

Van Zyl receives some intriguing news from his team.

Sophisticated sonar equipment has detected a large object

4,400 meters underwater on a flat plateau.

It could be the Helderberg.

And they presented me with a piece of paper

with a lot of black dots of various sizes on it,

and they said, "That's your wreckage."

And my question to them was,

"How do I know it's the wreckage of the 747?"

Maybe this is a submarine

from the Second World War or something.

And the response was just, "Rennie, it is it,

"because we tell you it is the wreckage."

But no one's ever gone that deep to salvage anything,

including the Titanic.

Van Zyl has no choice.

To find out whether the sonar images are

in fact the wreckage, he must launch

the most expensive part of the investigation,

Operation Resolve.

A remote controlled sub called theGemini will be sent

to the ocean floor to videotape what's there.

If it is the Helderberg, the Gemini will search

for key items, including the black boxes.

The problem is that the mini sub must

be attached to the mother ship by a flexible fiber optic cable

that's almost seven kilometers long.

No cable that long has ever been built.

We needed a 20,000 foot cable.

There was no existing cable,

so we had to go to a cable manufacturer

and get a cable designed and built.

But before the fiber optic cable is assembled,

Van Zyl launches a separate investigation

into the fire-fighting capabilities of the Helderberg.

He would discover that the very design

of the Combi may have doomed the flight.

Investigators want to know whether the Combi was

properly designed to protect the passengers

on South African Airways Flight 295 from fire.

The smoke should not have entered the Combi's cabin.

The American team leader in the investigation,

Barry Strauch, goes to Boeing's headquarters

in Seattle to find out how the Combi was tested

for certification in fire prevention.

Strauch's team learns that to comply

with federal regulations,

Boeing's fire tests were conducted by setting

a bale of tobacco leaves on fire.

When a technician enters the cargo area

to fight the demonstration fire,

no smoke enters the passenger cabin.

The smoke remains localized.

The fire is quickly extinguished.

Well, that was in the test conditions

that Boeing used to get the airplane approved.

But in the reality, as we saw in this accident,

it didn't work that way because, um, you didn't have

a nice clean fire with fans blowing

the smoke towards the ceiling.

You had pallets, you had a fire

that would have grown considerably

before the smoke is generated

and you had plastic sheeting

that would provide fuel to the fire,

in addition to all the cardboard

and packing materials within the pallets themselves.

The Combi is designed to prevent smoke

from entering the passenger cabin.

The air there is kept at a slightly higher pressure

than in the cargo area.

When the door between the two is opened,

the air should flow into the cargo area,

keeping the passengers safe.

Investigators then conduct their own test.

They set a large pallet of tightly packed cargo on fire,

mimicking conditions on the Helderberg.

The blaze is more intense and the temperature is hotter.

Investigators discover that this much hotter flame has

a radical impact on the air in the cargo hold.

When the cargo door is opened,

the smoke now flows into the passenger cabin.

Boeing tests used tobacco leaves and batches of tobacco.

In the fire in the Helderberg,

it was a very, very different fire

than the kind of smoke-generating fire

that Boeing used in their test.

Heat would have been generated within the cargo compartment

that would have created its own pressure,

and would have negated the pressure differential

between the cargo compartment and the passenger compartment.

And without the pressure differential

there would be nothing to restrain the smoke

and keep it on the cargo side.

And therefore, the smoke would have penetrated into the passenger side,

smoke that contained,

as we know, carbon monoxide and carbon dioxide.

Then investigators discover

something potentially more lethal.

As the passenger cabin filled with smoke,

a checklist instructed the crew to turn on the cabin's recirculating fans.

The intention of the checklist is to dissipate the smoke in the passenger cabin

after the fire has been extinguished.

Recirculating fan switches...

on.

But in this case, turning the fans on may have been deadly.

Fans draw air from above the cabin's ceiling

and from the cargo compartment,

before recirculating it back to the passengers.

The carbon monoxide levels were extremely high,

and were fatally high.

In fact, the one body...

And we have to stress again that he was allocated the seat

really below the recirc fan inlet area.

That was the highest level.

I think we're talking around about 66 percent.

That is not a survivable level at all.

By following their checklist, the crew may

have fed toxic gas into the passenger cabin.

And it might very well have been

that most of your passengers were asphyxiated before impact.

No checklist for a 747 Combi had

ever foreseen the Helderberg's simultaneous problems.

A cargo fire problem, and a cabin smoke problem.

The smoke removal checklist is predicated on the assumption

that the fire has been extinguished.

In that event,

descending to 14,000 feet and opening the cabin door

would be the appropriate thing to do.

It would get the smoke out of the airplane,

and enable people to breathe regular air.

If the fire hasn't been extinguished,

that would have the function of actually increasing the airflow to the fire,

and increasing the supply of oxygen to the fire.

We think that's what happened in this case,

that the fire had never been extinguished.

And in fact, the crew's attempts to make the situation better

may have in fact made the situation worse.

Investigators begin to realize

that fighting a fire in the Combi's cargo area is

much more difficult than previously thought.

If there was a fire in one of these pallets,

it was quite likely that by the time the crew was

alerted to the fire, it would be too late.

Then the cabin instantly filled up with smoke.

But Van Zyl still doesn't know

what caused such a fierce fire.

How had the blaze started,

and how had it brought the plane down?

The answers are still deep under the ocean.

It takes months to build the fiber optic cable

that's long enough for the Gemini to reach the bottom of the sea,

and to modify the submarine for this mission.

We had to take the ROV, existing ROV that we had,

which was designed for 6,000 feet,

and we had to modify it

so it would go to 20,000 feet.

Roy Truman's team had to give the sub thicker walls

to withstand the enormous pressure it would encounter,

and modify its cameras for the extreme depth.

On September the 23rd, 1988,

the Gemini begins its record breaking journey.

We were hesitant to say that everything would work,

because we didn't even have time to do sea trials

on all of this new equipment.

The cable allows technicians at the surface

to manipulate the Gemini at 4,400 meters.

It also carries video signals from that remarkable depth.

It's the first time that video images have

been recorded from this deep in the Indian Ocean.

Marine biologists are fascinated

by the discovery of unique new species.

Some of the stuff that we saw

on the sea bed was pretty mind-blowing.

Then one year to the day after it disappeared,

the Helderberg is found.

From a depth of 4,400 meters,

the submarine sends back images that could only be the wreckage

of South African Airways Flight 295.

There would be lots of luggage

just strewn all over the sea bed,

massive structures, the wings, the tail,

huge parts of the cabin split open,

and you could see all of the ribs,

and the wiring, the hydraulic piping.

I mean, it was incredible just to see

everything that went into a machine

spread over an area of about five, six square miles.

It was incredible.

Van Zyl's expensive gamble is beginning to pay off.

Descending to the Helderberg's wreckage is

a triumph for him and his team.

But just finding the debris isn't nearly enough.

A year after the accident,

Van Zyl is still hoping for the improbable,

the recovery of the cockpit voice recorder.

One of the major aspects we aimed at

in Operation Resolve was the recovery of the CVR.

We really wanted to know whether the cabin crew reported

to the captain that there was an explosion,

or what was happening at the back.

Hundreds of hours of videotape are recorded.

It's exhausting work.

If you can imagine being on a football field

with a flashlight,

that only illuminates a square foot of the football field,

and you're looking for an earring

one of the football players lost during the game

in the dead of night, that's similar to what

it's like when we're on the sea bed.

Then at nine o'clock one morning,

something catches the eye of one of the technicians.

Go back, go back for a second.

We might have passed something.

At long last, the black box is discovered.

There. That's it. That's it right there!

My God, we found it!

We found it!

That was a very fulfilling moment,

you know, find what we had aimed for,

we have achieved. We're getting it.

It takes a full five hours

for the Gemini to bring the black box up

from the bottom of the sea.

The South African media turns the discovery

into front-page news.

It's now 1989

and the Apartheid government is still running the country

with an iron fist.

Van Zyl makes an unusual decision.

He takes the sealed black box to Washington

and opens it there.

Because otherwise, I would have been accused

of having covered up something,

or left something out, or whatever.

And we, the FAA, and the NTSB guys

all listened to this tape at the same time for the first time.

Tension in the room is high.

The cockpit voice recorder should be a tape

of the last 30 minutes of the flight,

as the crew fought the fire.

But the tape turns out to be a major frustration.

After a year on the bottom of the ocean,

it's difficult to understand anything.

It was the worst time of my life,

sitting in the playback room at the NTSB facilities

and you watch the time,

and there is absolutely no indication of problems on the tape.

And I'm watching the clock.

At about 25 minutes I was

really getting very, very anxious.

For 28 minutes, the tape reveals nothing unusual.

Then everything changes.

The next minute, of course, the alarm bell goes on the CVR

and we had about a...

a minute's worth of relevant recording

on the tape before the tape stopped.

Normally the black box records

the final moments of a flight. But not this time.

Instead, investigators are able

to listen to the start of the accident

before the recording mysteriously stops.

It's not what Van Zyl was hoping for,

but it gives him crucial new insight into the fire.

Read out the fire checklist for us, please.

Fourteen seconds after the fire alarm goes off,

the plane's circuit breakers start to pop.

The breaker popped as well. Huh?

We'll check the breaker panel as well.

Yeah.

Investigators estimate

that up to 80 circuits were disabled.

The wires to the cockpit voice recorder are destroyed

only 81 seconds after the fire alarm first goes off.

Van Zyl has not received the key evidence that he hoped for.

But the fire is revealed as more violent than previously thought.

The recording leaves many questions unanswered.

But it does help Van Zyl to arrive at a personal opinion

as to why the plane may have crashed.

A lot of things were happening in the cockpit,

and we believe that he probably was faced

with up to 80 circuit breakers popping

in the cockpit at the time

may have made controlling

half the aircraft extremely difficult,

and the possibility then even

of the airplane just gradually descending into the sea.

Whether it was a controllable flight,

uh, I have my doubts.

I put myself in the cockpit on this thing and I said,

"I would have been terrified."

I mean, you know, we're just figuring. Now what do we do?

You know, did they do the checklist... correctly?

We'll never know.

But investigators still don't know

what triggered the Helderberg fire.

The mystery can now only be solved

by salvaging parts from the crashed plane.

We realized that what we had to do was just to continue

recover as much wreckage

as we could from the ocean floor.

Van Zyl's focus is on certain key pieces

of the Combi's cargo area.

They are brought to a hangar and re-assembled

like a giant jigsaw puzzle.

His plan is to reconstruct the section of the cargo area

where the fire most likely started.

Van Zyl discovers that the cargo area floor is untouched by fire.

So we know that the fire never burned lower than one meter off the cargo floor.

But the walls and ceiling

at the front of the cargo area reveal severe fire damage.

Van Zyl makes a dramatic discovery.

The seat of the fire was on the front right pallet of the cargo.

So we were looking at the very localized fire on one pallet.

The front right pallet was mostly filled with computers,

protected by polystyrene packaging.

Investigators suspect that a fire

within the pallet came in contact

with the polystyrene packing material,

producing gases which accumulated near the ceiling.

When the gases became hot enough,

they ignited into a flash fire

that spread throughout the cargo hold.

Once smoke penetrated the polyethylene sheets

that fire would have been very, very hot.

But even if the packing material had

helped spread the blaze, Van Zyl still didn't know why it started.

After millions of dollars,

and more than a year and a half of work,

he has to end his investigation.

I would have felt a lot better if we had been in a better position

to give more factual information

to the board to consider.

But that was not to be,

and we were not going to fabricate.

But interest in the wreck

of the Helderberg doesn't die.

Dark rumors circulate about a possible cause of the fire.

It's against this backdrop

of a very repressive Apartheid government.

At that particular time, the first thought, I think,

for many, many South Africans was what was on that plane.

Was there something in that cargo hold

that could have caused that terrible fire,

because planes don't just burst into flames midair and crash.

Then a South African government chemist makes a startling discovery,

which leads to a controversial new theory.

A microscopic iron particle on the nylon netting

next to the pallet has a unique profile.

The airflow patterns on the iron suggest

that it traveled at a very high velocity while in a molten state.

The discovery could mean

that the fire on the Helderberg was not

a flash fire triggered by packing materials.

This was a different kind of fire.

This was a fire that had its own oxygen.

If you can imagine something like a sparkler,

which has fuel and its own oxygen.

It was some kind of material similar to a sparkler

that we feel was the cause of the fire.

A British fire and explosion analyst examines

the exterior skin of the plane above the pallet

and comes up with another piece of evidence

to support the new theory

The skin on the outside of the plane reached

temperatures as high as 300 degrees centigrade.

You must remember that it's very difficult

to burn through an airplane skin in flight,

because the tremendous amount of cooling from the airflow on the outside of the skin.

Dr. David Klatzow is one of numerous experts

who question what caused the fire.

It would have involved substances

which normally would not have been carried aboard an aircraft,

particularly a passenger aircraft.

In other words it could not have been a normal packing material,

wood, cardboard, plastic fire.

You don't carry the things of that nature,

which carry their own oxygen,

which can produce an accelerated fire

for a number of reasons.

One of which, they are generally unstable.

The second reason is that normal fire extinguishing methods will not put them out.

What could start such a fire?

The only dangerous goods listed

on the cargo manifest are computer batteries.

Some believe the Helderberg must have been carrying cargo that wasn't listed.

At the time, South Africa was under

an international arms embargo.

The country was also fighting a war with Angola.

South Africa didn't have capacity

to do everything itself, and there were times

when it had to buy from other countries.

SAA was seen as a surrogate cargo carrier

that they could somehow,

through its commercial airline use,

also bring in substances

for the South African government

undercover, under protection, no questions asked.

It was not that easy for them to fly a quasi-military airline

into different countries and pick up military contraband,

which you must remember we were laboring

under an arms embargo at the time.

The media fuels the flames of suspicion

that the government was using passenger jets

to secretly import weapons.

Armscor is the corporation responsible for supplying

the South African forces with munitions.

At the time, there was a need

to produce a better rocket system,

a more efficient rocket system,

for dealing with the air menace in Angola.

And the rocketry systems which are used

for those purposes have as their propellant...

the major component of the propellant is ammonium perchlorate.

And that is what I believe was

being carried aboard the Helderberg.

But it is not the sort of compound

you want on an aircraft

when you are flying on that aircraft,

because it is unstable.

It is susceptible to self-ignition

by any kind of vibration and violent movement.

The official investigation

into the crash does not come to the conclusion

that the Helderberg was carrying illegal arms.

But the rumors won't go away.

And more than 10 years after the crash,

the dark theories force

a very different South African government to take another look.

The Helderberg accident revealed

that the 747 Combi was

vulnerable in the event of an onboard fire.

South African Airways immediately stops using the 747 Combi.

American officials take notice.

And the FAA went through and developed some new regulations,

but for the weight and everything that was

going to have to be added in there did not make it economically feasible.

And, so essentially after the Helderberg accident,

747 Combis were not used anymore.

There are tributes and memorials to the 159 victims,

but closure does not come easily for the families.

I need an answer for why I was orphaned at 14.

And I feel that...

as I say I'm probably touching on hearsay,

but there's a lot of evidence

that does point to something not being right on that flight,

and that the flight was carrying something illicit.

Ten years after the Helderberg crash,

the new South African government,

launches a commission to reexamine the accident.

Okay.

The Truth Commission was tasked with basically uncovering

the truth about Apartheid atrocities,

and one of the areas it was tasked to look at was the role

of the SAA in sanctions busting during the '80s,

and whether or not the Helderberg was

a freak accident or not.

In 1998, the Truth and Reconciliation Commission

makes a controversial conclusion.

Namely, that nothing that was listed in the cargo manifest

could have caused the fire.

And the Truth Commission recommended that there was

something untoward about what had happened to the Helderberg.

The Truth and Reconciliation Commission exposed the improbabilities

of the government version as to what had happened.

If nothing in the cargo inventory caused the fire, what did?

And how did it get onboard?

The reality unfortunately is

unless somebody today comes up and says,

"Yes, I did this," or "Yes, we were responsible for this,"

and you can prove them not to be involved in a hoax,

that will be possibly the only time

in which we will really know

what had happened in and caused

and was the source of ignition of the fire.

In its final report, the Commission suggests

that the Attorney General's office continue

to investigate the accident.

But surprisingly, that has never happened.

The ANC-led government hasn't pursued that.

And of course, we have to ask ourselves why.

And I think that the answer lies

in what many people believe is

that it's just going to be too costly.

They don't want to open it for the simple reason

that it would be financially disastrous for the airline.

Rennie Van Zyl devoted years of his life to solving

the mystery of the Helderberg.

His inability to definitely prove

the cause for the fire does not stop him

from seeing the benefit of his investigation.

I believe that we as a team had done the best that we could

under extreme challenging conditions

and circumstances.

What we had done had never been done before.

It was pioneering work.

The frustration is we could not establish the source of ignition

and we will probably never know.

I believe that those people are still out there

that know exactly what happened to that aircraft.

I know that the thought processes

at the time were, "Our country was at war,

"and they were doing their duty for their country,"

but I just feel that they should have

a heart for the families and bring out that information.