Original subtitles

(narrator): The world watches in horror

when an airliner is turned into a weapon of terror.

- American 77, being part of September 11, 2001,

was front-page news.

(narrator): A massive blast tears apart a jumbo jet and shocks the world.

- A TWA jet aircraft, Flight 800,

has exploded in mid-air.

(narrator): And a supersonic marvel becomes a flying inferno.

- Oh, mon Dieu. - It captured the attention of the world,

because this was the first major accident involving this airplane.

(narrator): Three devastating crashes make headline news around the world.

The attention puts intense pressure on investigators

to uncover the true cause of these deadly disasters.

- We don't care about blame, we don't care about speculation.

We wanna know what the hard facts really are.

- Mayday, mayday.

- It's going up!

(indistinct radio chatter)

(narrator): It's nearly 8 a.m. at Dulles Airport near Washington, DC.

American Airlines Flight 77 will soon be heading to Los Angeles.

Thirty-nine-year-old David Charlebois is the First Officer.

- Any plans for the big day?

Gonna take in the ballgame at Angels Stadium.

- Oh, yeah? That'll be great.

(narrator): The captain, Charles Burlingame, turns 52 tomorrow.

He's a former Navy Top Gun pilot with years of experience flying airliners.

- Can I help you with that?

(narrator): The Boeing 757 is less than half full this morning.

There are only 58 passengers and six crew on board.

- On the roll.

(narrator): At 8:20 a.m., American Airlines Flight 77 gets underway.

- V-1.

Rotate.

(narrator): The trip from Washington to Los Angeles

is approximately 2,300 miles across the country.

At 8:46, Flight 77 reaches cruising altitude:

35,000 feet.

- American Airlines 77, clear direct Falmouth.

- Clear direct Falmouth, American 77.

(narrator): The air-traffic controllers guide the 757

to the next waypoint enroute to Los Angeles.

- Alright. Time for a bit more coffee.

(narrator): But 34 minutes into the flight,

controllers notice something odd.

- What are you guys doing?

(narrator): Flight 77 is veering off course.

- American 77, Center.

- At the point where the controller noticed the aircraft take a turn

that he did not instruct him to do,

that's when he would become concerned.

(narrator): Two minutes later...

- American, uh, 77, radio check.

(narrator): ...Flight 77 vanishes from their radars.

(phone ringing) - Center.

(narrator): Then a phone call from American Airlines brings unbelievable news.

Thousands of people are feared dead

after two planes crash into the World Trade Center towers in Manhattan.

The United States is under attack.

- Almost everybody that saw what happened said,

"This is not an accident."

(narrator): While the world watches the horrifying news in New York,

concern grows over the missing 757.

- Supervisor.

(narrator): Controllers fear they may have another hijacked plane in the sky.

- I've got a target tracking eastbound at a high rate of speed.

(narrator): At 9:32, more than half an hour after losing contact with the plane,

controllers spot a mysterious radar return.

If it is Flight 77, it means the plane has turned back towards Washington.

- It's gotta be our plane.

Center calling American 7-7. American 7-7.

(narrator): But the 757 is ignoring all radio calls.

And at 9:35 a.m. ...

...the plane slams into the Pentagon.

All 64 people on board are dead.

125 others inside the building are killed.

(sirens wailing)

- We have watched the tragedy of an outrageous act of barbaric terrorism

carried out by fanatics against both civilians and military people.

- American 77 was...

front-page news and changed America.

It stayed in the news a very long time.

(narrator): The crash of Flight 77 turns the Pentagon into a federal crime scene.

The FBI is in charge of this investigation.

Because the crime scene is also an aviation crash site,

the National Transportation Safety Board joins the high-profile investigation.

Tom Haueter was one of the first NTSB investigators at the scene.

- The FBI's experts on criminal investigations,

and that covers many areas,

they aren't necessarily airplane experts.

(narrator): While recovery teams race to find the plane's black boxes,

FBI agents gain valuable details about how the plane was turned into a weapon of terror.

- Everyone to the back of the plane! Now!

(narrator): Some passengers managed to make phone calls from the air

describing their ordeal.

(people screaming)

Those phone calls reveal that the hijackers were equipped with box cutters and knives.

They forced the pilots to leave the cockpit.

- Please, stay calm. Everybody move to the back.

- Prior to the 9/11 terrorist attacks,

all flight crews were told to cooperate with the hijackers and bide for time.

(narrator): But how did terrorists get weapons past security at a modern airport?

And how were they able to fly a sophisticated airliner straight into the Pentagon?

At the crash site, the exhaustive search effort has paid off.

Agents recover the plane's two black boxes.

If their data can be successfully downloaded,

it might reveal what was going on in the cockpit when controllers lost contact.

- Center calling American 7-7. American 7-7.

(narrator): While investigators wait for the black-box data,

they scan Flight 77's passenger manifest,

checking to see if any suspicious names are listed.

- It didn't take too long to figure out who the hijackers were.

(narrator): The trail leads to five attackers.

But how did they get past airport security?

- The computer-assisted passenger pre-screening system

flags you if you have certain suspicious indicators.

(narrator): Investigators wonder if the pre-screening system failed.

They study the records for Flight 77,

and discover that the screening system flagged three of the five hijackers

for extra security checks.

Yet they still got through.

- Customer service and...

moving people through the airport

was the top priority, not security.

(narrator): A review of airport security video

shows one of the hijackers set off an alarm.

(beeping) - Metal detector caught the weapon.

(narrator): An officer scans the suspect with a handheld detector.

(beeping) When nothing shows up, he's allowed through.

None of the hijackers get a rigorous inspection,

and all five board the flight without issue.

- At the time, the bar was set very low for individuals coming through the checkpoint.

Knives of no greater than four inches in blade length were allowed on board,

at the time, under FAA policy.

(narrator): But getting on board was only the first step.

- Everyone to the back of the plane! Now!

(narrator): The big mystery to solve now

is how the hijackers were able to carry out the rest of their murderous plan.

(narrator): While the news from 9/11 dominates international headlines,

FBI agents unearth a trail of documents connected to American 77's hijackers.

They come up with a crucial lead.

One of the suspects, Hani Hanjour,

spent several years training to become a commercial airline pilot.

- He ended up doing flight training in Arizona,

and was kind of unusual in his flight training,

'cause he flunked a lot of checks along the way.

(narrator): As part of his preparation,

Hanjour also practised on small private aircraft.

- Turn right, American 77.

(narrator): But flying a sophisticated airliner is very different

from piloting a small private plane.

How did the hijackers steer a 757 towards a target 35,000 feet below?

Investigators hope the plane's flight data will provide some answers.

- Unfortunately, the cockpit voice recorder was too damaged,

and no information could be recovered from it.

But we were able to read out the flight data recorder.

- Banking left nice and smooth. It must be the autopilot.

(narrator): The data reveals how the hijackers managed to turn the 757 around.

- This heading should take us back to DC.

(narrator): They relied on the plane's automation.

- You don't need to be a pilot at all when the autopilot's on.

He can put a heading into the autopilot, airspeeds into the autopilot.

Everything can be done for him very smoothly.

- Descending now.

(narrator): But the autopilot isn't pre-programmed to fly

to the precise location of the Pentagon.

- It's just ahead. Autopilot off.

(narrator): Eight minutes from impact,

the hijacker must fly the aircraft by hand.

- It's quite clear, looking at the data,

this is somebody who has never handled a big airplane before.

- This guy is really struggling. - Keep it steady!

- We're way too high! We're never gonna hit it!

(narrator): To shed altitude, they make a sharp diving turn to the right.

- The aircraft can only come out of the sky so fast without breaking up.

So he makes a circle to get the aircraft lower

and get it into position to hit the Pentagon.

(narrator): In the final seconds, they accelerate to top speed,

almost to the point of break-up.

(automation): Terrain. Terrain. - The airplane's overspeed warnings are probably going off.

He doesn't care.

(screaming)

(narrator): Investigators now understand

the deadly flight path of American 77.

They have no doubt the attack was planned down to the last detail.

Investigators speculate that a flight attendant was forced

to hand over the keys to the cockpit.

- Open the door or we'll cut your throat.

(exclaiming) - Okay. Okay.

(narrator): There was no time for the pilots to warn authorities.

Once inside the cockpit, investigators believe

that hijacker Hani Hanjour took control of the plane.

- You have to let me back in the cockpit. - Stay where you are now or die!

- I've got a target tracking eastbound at a high rate of speed.

(narrator): By the time controllers spot Flight 77's radar return,

the plane is only five minutes from DC.

- There's nothing the controllers could've done.

- Allahu Akbar!

(indistinct radio chatter) (sirens wailing)

- 9/11 shook us to our core.

Anybody that was of age during that time... it has marked our generation.

(narrator): The 9/11 attacks bring about the most profound changes ever

to commercial aviation,

both in the U.S. and around the world.

Just two months after the attacks,

the U.S. government creates the Transportation Security Administration, or TSA.

It establishes strict new rules on what passengers can carry on planes.

Airports start screening passengers with full-body scanning machines.

There are also major changes to cockpit security.

- The most important takeaway is this: We must,

absolutely must deny access to the cockpit

to anybody who would use the airplane as a weapon.

And we have been marvellously successful in building that kind of defence system.

(narrator): But not all front-page stories are criminal cases.

(exclaiming) An explosion on a passenger jet sends investigators

on a four-year search for answers.

- People couldn't understand how a modern jetliner could just blow up in flight.

TWA 800 was a front-page story on the news for over 18 months.

(narrator): It's a hot summer evening

at John F. Kennedy Airport in New York.

Trans World Airlines Flight 800 is delayed due to a baggage problem.

212 passengers are on board the Boeing 747 enroute to Paris.

- We gonna start placing bets on when we actually push off?

(narrator): Captain Ralph Kevorkian is an experienced pilot

on his second training flight as a 747 captain.

- Twenty dollars on us getting outta here before sundown.

- I'll take that bet. (laughter)

(narrator): First Officer Steve Snyder has flown for TWA

for more than 30 years.

After over an hour,

the luggage issue is finally resolved.

- Ladies and gentlemen, from the flight deck, we've been cleared to go.

We'll be pushing back from the gate shortly. (applause)

Takeoff thrust.

(narrator): At 8:19 p.m., TWA Flight 800 is airborne,

steadily climbing to 15,000 feet.

- Climb thrust.

- Power set.

(narrator): But 11 minutes into the flight, disaster strikes.

(exclaiming)

- Talk to me! What do you have for us--

(screaming)

- The front of the airplane that broke off,

the centrifugal force had to be just horrendous as the nose fell down.

(narrator): What's left of the plane continues skyward, engulfed in flames.

- Went up at least another 1,000 feet,

maybe 1,500 feet, you know, and flames pouring off it.

(screaming)

- We now know that a TWA aircraft, Flight 800,

has exploded in mid-air, apparently landing in the Atlantic Ocean tonight.

(narrator): Debris litters the water nearly 75 miles east of Manhattan.

There are no survivors.

A media swarm descends as recovery efforts are underway.

The large debris field tells investigators

that the plane likely came apart in mid-air.

- Me and my cousin Joe, we was over by the dock over there.

He said, "Yo, Darren, look up in the air. There's a big ball of fire."

(narrator): The high-profile crash of TWA 800

leaves the nation in shock.

Did a bomb take down the plane?

- It was so horrific, so many people were lost.

747s do not normally come apart in the air.

So there's something extraordinary that happened here.

(narrator): The NTSB's lead investigator, Al Dickinson,

faces an urgent task.

- It was extremely important for us to find out what happened,

because there were so many 747s flying at that time.

(narrator): The NTSB will lead the investigation.

- Yeah, you can take that just down over there.

(narrator): But the FBI launches its own parallel criminal inquiry.

- Nice to see you. - Just wish it was under better circumstances.

(narrator): The FBI believes the mid-air explosion could be linked to terrorism.

- I'm sure this was a bomb,

and that we'll find the evidence of that in this wreckage.

Just keep me posted. - Alright.

(narrator): Three years earlier, in 1993,

terrorists drove a bomb into the World Trade Center.

And just one year prior,

Timothy McVeigh bombed the Federal Building in Oklahoma.

NTSB investigators carefully search the wreckage for any sign of foul play.

- No pitting.

- No cratering.

Nothing.

(narrator): Investigators know the plane exploded in mid-air,

but they are convinced this was not a terrorist act.

- In a way, it made the Safety Board's job much more difficult,

because we had to now determine what happened if there was no bomb or missile

that caused the airplane to come down.

- Alright, let's get to it.

(narrator): But news reports continue to fuel the FBI's terrorism theory.

The pressure is on the NTSB to find the cause and provide answers

to grieving families.

- Excuse us.

(narrator): Seven days into the investigation,

the ocean salvage team makes a major find: the black boxes.

- Recovering the CVR and the FDR

is very important in every investigation.

The trouble is, you never know what you're gonna get.

(narrator): Technicians in Washington recover the data.

- TWA 800...

(narrator): But it gives investigators little to go on.

- ...leaving 1-3,000.

(narrator): They hear no cockpit alarms or signs of panic from the crew.

- ...climb and maintain 1-5,000.

- Normal conversations in the cockpit,

normal readouts on the flight data recorder,

up until the point where a sharp noise was heard and then nothing after that.

(narrator): With no help from the flight data,

investigators scour the wreckage for clues.

- Give me a hand with this.

- The wreckage recovery started to, uh, teach us some things.

(narrator): They uncover a piece with significant scorching.

Where it's found tells investigators

it was one of the first pieces to come off the plane.

But what part of the plane did it came from?

- A piece of spanwise beam from the centre wing fuel tank.

- I think this could be it.

(narrator): It's a discovery that changes the direction of the entire investigation.

- The explosion must've started somewhere inside the fuel tank.

(narrator): To prove their theory that an exploding fuel tank

took down TWA 800... - We're gonna put all this back together again.

(narrator): ...the NTSB decide to attempt something that has never been done before.

- We're gonna rebuild the entire plane.

(narrator): Piecing together the shattered 747

will be the only way to convince the world it was not a terrorist attack.

But investigators still don't know what sparked the blast.

- If you find evidence of an explosion in a fuel tank,

you have to look for what could cause...

an explosion to start, and you work backwards.

- We need to prove three things. The fuel was flammable...

The explosion has to be powerful enough to rupture the tank.

And finally, something created a spark to ignite the fuel.

(narrator): Jet fuel in its liquid form is not flammable,

but when heated, the fuel starts to vaporize.

When combined with oxygen already present in the tank,

this vapour can become highly flammable.

At 14,000 feet,

jet fuel needs to reach 96° Fahrenheit to become combustible.

Investigators examine the design schematics of the aircraft.

An intriguing detail catches their eye.

- The placement of the air-conditioning units were underneath the centre tank,

and those generate a fair amount of heat.

(narrator): On the day of the fatal flight,

the air-conditioning units were working extra hard

to keep the cabin cool on a hot evening.

Could heat from the units have boosted the temperature

inside the tanks to a dangerously high level?

- We had to prove that the temperature inside the tank would be flammable,

because if we couldn't prove that, how was it gonna explode?

- Only one way to find out.

(narrator): Investigators decide to recreate the fatal flight.

But it puts them in the same dangerous situation...

- Air conditioning on. (narrator): ...that took down TWA Flight 800.

- Alright, let's start it up.

(narrator): Investigators perform a risky flight test.

They need to prove the fuel on board TWA Flight 800 became flammable.

- It was a bit disconcerting, because we were, in a sense,

in an aircraft that was identical to the accident flight.

Now, if you're gonna ask me whether I would do it again, I'd probably say no.

(narrator): When the test flight reaches the same altitude as TWA 800...

- Holy crow.

This is off the charts!

(narrator): ...the temperature readings in the tank are terrifying.

The air-conditioning packs heat the fuel to 127° Fahrenheit,

30° above the flashpoint.

- Okay. Let's get back down to the ground.

So we've proved flammability.

Now for the second challenge: Can the tank rupture?

(narrator): They rig up a scale model of the centre wing fuel tank.

- Gentlemen. Level's good?

(narrator): They fill the tank with the same ratio of jet fuel,

and heat it to the same temperature as on TWA 800.

Investigators then ignite the fuel.

The results are clear.

The explosion creates double the amount of force necessary to rupture the tank.

- The tank simply wasn't strong enough

to contain the full scale of this explosion.

(narrator): NTSB investigators need one last critical element of proof.

- The final question that we had to answer was:

What caused the spark?

(narrator): Investigators take a closer look at the aircraft's electrical system.

After hours of examining the 180 miles of wiring,

they notice a disturbing pattern.

- The condition of these wires is abysmal.

(narrator): High-voltage and low-voltage wires are mixed together,

making it possible for strong currents to travel where they shouldn't.

- If you have cross-currents into these wires,

something drastic could easily happen.

(narrator): The condition of the aging wires

leads investigators to a logical conclusion.

- This was certainly a short-circuit.

It was more than enough to create a short-circuit

that would go into the fuel tank and ignite the vapours.

- And now...

...we have all the conditions for a fuel-tank explosion.

(narrator): The full sequence of events is now clear.

While idling at the gate for an hour,

the air-conditioning system heats the fuel in the centre wing tank.

The liquid turns to vapour, as its temperature rises above the ignition point.

In the plane's aging electrical system,

some wires are so worn that they short-circuit.

In the blink of an eye,

deadly voltage reaches the fuel probe inside the centre wing tank.

- And then it blew up.

- Talk to me! What do you have for us--

(narrator): The NTSB's ambitious reconstruction of TWA 800 is finally complete.

It confirms the investigators' fuel-tank explosion theory,

finally putting any bomb-conspiracy theories to rest.

- I was really pretty proud of the definitive nature

in which we were able to show where the airplane break-up began.

(narrator): After more than four years of investigation,

the NTSB recommends, in its official report,

that all Boeing 747s undergo a review and repair of older wiring.

They also call for additional insulation

between the fuel tanks and the air-conditioning system.

- There was a lot of design challenges,

there were a lot of certification challenges,

and these recommendations went forward to both the FAA and Boeing,

but it was all hardware-related.

(narrator): Despite the constant speculation in the news,

the NTSB persevere in finding the true cause.

(crowd cheering) Just four years later,

investigators face a similar challenge

when another devastating crash makes international news.

Charles de Gaulle Airport, Paris.

One of the busiest airports in Europe and the only place in France

to catch sight of the world's most famous passenger plane:

Concorde.

- Concorde flying was a real show.

I mean, everybody was watching.

It was spectacular.

(ATC): Air France 4590, do you want Whiskey-10 or Romeo?

(ding) - I need all the runway, eh?

(ATC): Okay. Taxi for Romeo, Air France 4590.

(narrator): Today, Captain Christian Marty will be flying the Concorde.

- Clear on the right?

- On the right is clear.

(narrator): First Officer Jean Marcot will monitor the instruments.

With more than 23,000 flight hours between them,

Captain Marty and First Officer Marcot

are among the world's most elite pilots.

- Air France 4590, runway 26 right,

clear for takeoff.

- Everybody ready? - Yes.

(narrator): The Concorde is a technological marvel.

It's the world's only supersonic airliner.

(ding) - Four greens.

(narrator): Its takeoff speed is 198 knots,

40 knots faster than a 747.

- V1.

(narrator): They've reached V1, also known as "decision speed."

They're now going too quickly to abort the takeoff.

- Watch out!

(narrator): Suddenly, the plane begins veering left.

- Stop! (alarm sounding)

(narrator): They are running out of runway. (alarm sounding)

Captain Marty has to lift the jet into the air.

- 4590, you have flames behind you. - Roger!

Watch the airspeed. (alarm sounding) (indistinct chatter)

(screaming)

(narrator): The plane has lost two of its engines.

- No time!

(narrator): The crew can't out-fly the fire

that is rapidly consuming their plane.

- No! (narrator): The supersonic marvel of modern aviation...

...crashes into an airport hotel.

All 109 passengers and crew on board Concorde are dead.

Four more people have been killed on the ground.

- Everyone had a dream of flying on the Concorde.

And when you saw those horrific pictures,

you had the... sinking feeling that this might be the end

of supersonic travel for a while.

(narrator): The crash of the Concorde makes headline news around the world.

And all eyes are on French investigator Alan Bouillard,

who leads the inquiry into what caused the first fatal crash

in its 31-year history.

(in French):

We were dealing with a very complicated plane

that had been completely destroyed by fire.

There were very few pieces left.

(narrator): Bouillard's team begin their investigation on runway 26 right.

- It looks like they were bleeding fuel.

(in French): We became interested in the runway,

because the event happened during the acceleration for takeoff.

(in French): First of all, it was obvious that there were traces of fire

that were still visible on the runway,

as well as traces of fuel and many airplane parts.

So we had to collect all these parts to preserve them for the investigation.

(narrator): The two black boxes are recovered from the crash site.

They're rushed to the lab to see if their data survived the fire.

Among the runway debris, something captures Bouillard's attention.

- Well, I know this is a piece of the fuel tank.

- Among the first pieces recovered from the site...

...was a part that was quickly identified as being from one of the fuel tanks.

(narrator): Concorde has 13 fuel tanks:

one in the tail section,

and 12 more that combine to fill almost the entire Delta wing.

It means at least one of the plane's 13 fuel tanks ruptured during takeoff.

- It must've been a massive fuel leak.

That's the only way to explain a fire like that.

(narrator): But what could've caused such a massive leak?

Fortunately, technicians have salvaged the cockpit voice recording.

- Okay, let's get going.

(narrator): Bouillard hopes the pilots' cockpit conversation will shed some light

on the puzzling collection of leads.

- Four greens.

- V1.

(narrator): But just before liftoff, there's a loud noise.

- Watch out! - That sounded like some kind of explosion.

(narrator): Bouillard knows the precise moment the deadly fire began,

but he still doesn't know what caused it.

- Failure! Engine 2! (alarm sounding)

(narrator): Because Concorde includes American-made tires...

- I would love to get a look at that runway debris.

(narrator): ...the National Transportation Safety Board sends Bob MacIntosh

to join the team.

Among the debris found on the runway,

there are large, torn pieces of aircraft tire,

some weighing more than nine pounds.

- Looks like a blowout.

There's a whole lot of structure and rubber belt around the tire

that's probably gonna separate, and that's, of course,

a potential for damage.

(narrator): Concorde's tires are reinforced with a strong rubber belt

and filled with high-pressure nitrogen. (beeping)

When they rupture, they can act like small bombs.

- Maybe a piece of the tire flew up and burst the fuel tank here in the wing.

(narrator): So what could've caused a relatively new tire to erupt?

- We uncovered many incidents where tires were punctured or destroyed,

and in some cases, the rims, as well.

(narrator): Investigators take a closer look at the debris from the runway.

- Maybe something cut... into the tire.

(narrator): They discover a strange metal strip.

(in French): The shape of the metal strip that we found

was exactly the same shape as the tire debris.

- I want to know what this is and where it came from.

- It didn't look like anything that came from an aircraft to me.

(narrator): But metallurgical tests show it was made

of lightweight titanium often used in aircraft parts.

It's covered in a reddish-orange adhesive used in aviation repairs.

But it doesn't match any known pieces of the Concorde.

Investigators work to narrow down which plane it comes from.

(in French):

We searched by elimination.

We knew that it was a strip of metal that didn't come from the Concorde.

(narrator): Investigators pour over aircraft schematics.

- What is this?

(narrator): The metal strip looks like it could be from the engine of a DC-10.

- Certainly, there was a great deal of anticipation.

Could this be really from a, uh, a DC-10?

(narrator): Investigators search through the flight records for runway 26 right,

and make a crucial discovery.

A DC-10 took off just minutes before the Concorde.

Investigators are convinced the thin strip of metal fell from that DC-10...

- V1. ... where it ruptured a massive Concorde tire...

...that fatally burst the fuel tank.

The investigators' theory may explain

one of the most shocking aviation disasters the world has ever seen.

Now all they have to do is prove it.

(narrator): Investigators test their theory that a metal strip

could've burst the brand-new Concorde tire.

Using an identical tire, they run over a replica of the metal strip with a weight

equal to flight load: 25 tons.

They get their answer.

- You can't ask for better proof than that.

(narrator): However, if a piece of flying debris ruptured the tank,

the tank should be bent from the outside in.

But the tank fragment from the runway is bent in the opposite way.

Investigators face an unprecedented mystery.

What punctured the Concorde's fuel tank from the inside?

- The only thing in the fuel tank is the fuel.

Maybe what burst the tank... is the fuel itself.

(narrator): When a high-speed projectile hits a container full of liquid,

it can set off a tsunami-like wave

powerful enough to rupture the container

at a different point from where it was struck.

- Set it so the fuel tanks are completely full.

(narrator): Bouillard hopes a computer simulation will show if that's what happened.

- Okay... let's watch what happens.

Fire.

(narrator): Investigators work to recreate the exact moment

the tire fragment hit the fuel tank.

But conditions have to be just right.

- Fire!

(narrator): And when they are...

- We've got it! Well done.

(narrator): ...firing a piece of tire at the tank

can make it burst from the inside out.

- It was a revelation to all of us, and indeed, a very plausible explanation.

(in French): We were convinced that from the moment the plane rolled over the metal strip,

a catastrophe was inevitable.

(narrator): When the tire blows and the fuel ignites,

the crew faces an unprecedented dilemma.

At V1 speed, the massive jet needs more than a mile to stop.

(alarm sounding) (woman): There's a fire!

(narrator): But there's only 1,000 yards of runway left.

The pilots have no choice but to put the burning plane in the air.

(in French):

Aborting the takeoff at 180 knots would also have led

to the total destruction of the aircraft.

- Watch the airspeed.

(narrator): The crew fights hard to keep the plane flying right up to the very end.

- No!

(narrator): The accident report makes a number of recommendations

to make Concorde safer.

Engineers design stronger tires that can better withstand

the plane's high speed and immense weight.

Fuel tanks are reinforced with Kevlar to prevent leaks.

Airport authorities also implement a better system for monitoring runways

and removing debris.

- What is puzzling is that you had a piece of metal on the runway.

It turns out to trigger...

one of the most catastrophic crashes in aviation history.

(narrator): The Concorde does fly again.

But the return of the world's only supersonic plane doesn't last long.

Two years later, with rising costs and failing profits,

the Concorde is retired.

It makes its last flight on November the 26th, 2003.

- It was such front-page news, because people were sad.

I think the public realized it was probably the end of an era.

(narrator): When tragedy strikes,

whether in the middle of an ocean or in the heart of a city,

aviation disasters grip the public's attention

and make headlines around the world.

- What people really want to know is that somebody's got the facts,

and its being addressed, so it doesn't happen again.

(narrator): But even in the midst of a media frenzy,

investigators persevere and solve critical cases.

- We don't care about blame, we don't care about speculation.

We want to know what the hard facts are,

and we want to follow it wherever it leads.

Subtitling: difuze