Impact! A Horizon Guide to Car Crashes

This programme contains scenes which some viewers may find upsetting

For most of human history, this was as fast as any human could travel.

But then came steam...

..the Industrial Revolution

and the internal combustion engine.

Cars transformed our world.

They made travel easier, more accessible

and faster than ever before.

But speed also brought danger.

For more than sixty years,

Horizon and the BBC have reported on how scientists and engineers

have worked tirelessly to make road deaths a thing of the past.

These scientists have often immersed themselves in controversial

and disturbing research.

In this programme, we'll chart the key scientific breakthroughs

and the struggle to apply them to the real world.

For many of the last sixty years,

cars have been one of the major causes of death

amongst young adults in this country.

In fact, in the early 1980s if you were between the ages of four

and forty-four, you were more likely to die from traffic accidents

than any other cause.

It's Friday night near Reading

Despite the frantic efforts of his rescuers,

in a few moments from now a motorist will be dead.

When I arrived, he was...

His pulse was gone.

His airway was blocked, actually,

although he was alive, apparently, when the ambulance first arrived.

Alex Blackhall had taken a gamble and lost.

His death was quite unnecessary

His car had overturned but was otherwise undamaged

and he'd escaped without a cut

but like two out of every three British motorists,

he hadn't been wearing his seat belt.

At the time thousands of people were needlessly dying

every year on the roads.

And although these images were shocking,

the broadcast of Alex Blackhall s death in 1981 highlighted

like never before that very issue.

These pictures fuelled a debate that would transform road safety.

It was a broadcast that helped lead to an historic victory

in the struggle to save lives.

Getting into your car in the morning

and driving off is about as routine as routine gets.

It's completely automatic.

We don't really give it a second thought

but if I'd been around, say, fifty years ago,

I like to think I would have been a bit less carefree because

back then in the 1960s,

up to 8,000 people a year died on Britain's roads.

It's a truly horrific figure.

Now today, that's dropped to about 2,000, which is still too many

but it's a significant improvement, especially when you consider

how many more cars there are on the roads, but what's led to that

improvement and is there any way we can reduce casualties even further?

Back in the 1950s,

most car manufacturers tended to focus on style above all else.

They seemed relatively unconcerned by the number of people

dying in crashes.

However, scientists felt differently.

They couldn't accept that

something as domestic as the car could be causing so many deaths

As far as they were concerned, crashes were preventable.

When scientists examined the cause of collisions,

they found up to 85% were a result of human error.

So it seemed logical that the way to stop crashes happening was to

change driver behaviour.

The first question that needed an answer was

why drivers made so many mistakes.

Psychologists set about running some experiments, not very hi tech

but even so, they would reveal the root cause of all driver error.

Manchester University's Professor John Cohen was

one of the pioneering psychologists.

One of Cohen's own experiments is a classic in its field.

His experimental subjects were Manchester bus drivers

such as Len Reeder,

an instructor who's been driving for 22 years,

and George Jones, in his first week of instruction.

To begin with, I would like you to sit in the cab of the bus

and look at the gap between these two posts, and tell me for different

size gaps how many times out of five you think you could drive through.

Shall we begin?

What will be measured first is the driver's assessment

of the risk as the gap is slowly opened up.

Can you tell me how many times out of five you think you can

drive through that gap?

None.

This is the first of two separate measurements, risk and hazard.

Risk refers to the state of mind of a person, what he thinks

he can do in a particular situation, whereas hazard refers to the

actual performance as measured in that particular situation.

How many times out of five? Every time.

How many times out of five?

None.

How many times out of five?

Five.

Would you replace the markers now, please?

Now this time, we'll open the gap bit by bit and I want you to drive

through as soon as you can.

The gap is gradually opened again and this time,

when it's just wide enough, Mr Reeder brings his bus through.

There's no doubt that this driver is exercising skill.

He drives through leaving no more than an inch for the full length

of the bus and in this, he has much greater skill than

the younger drivers, but Cohen's hypothesis was that in avoiding accidents,

his skill matters a great deal less than his judgment,

that gaps that he thinks are wide enough, he can actually get through,

while those that he thinks are too narrow, really are too narrow.

And in the fifteen years since this first experiment,

it's now been firmly established that a low accident rate

depends on this one factor more than any other.

Professor Cohen's work showed that a driver's skill could be separated

from his ability to make sound judgments,

and it was the latter, poor judgment, that caused accidents

So the next question psychologists had to answer was

what makes drivers misjudge a situation?

They found there were two key culprits.

Cambridge psychologist Dr Ivan Brown revealed

the effects of the first, and most universal factor, fatigue.

With this clue that it was judgment and not skill that matters,

Brown was now able to examine the effects of fatigue on driving.

So far, studies both in the laboratory

and on the road had failed to show any significant effect on skill

so he set up this experiment with human observers.

The subject was tested twice, at the beginning

and end of a seven hour drive,

by two highly trained police drivers sitting in the back of his car

They can see not only any

minor infringements of the law that he may commit,

but also, they'll use their judgment to note any even slightly unwise action,

any discourtesy to other drivers or pedestrians, and they

press a button every time they spot something they wouldn't have done.

After seven hours' driving, the usual result is 40% more faults,

not in skill, but in judgment and courtesy.

The understanding that tiredness can cause drivers to make more errors

of judgment was a breakthrough

However, there was another greater threat to sound judgment

revealed through an extension of Professor Cohen's work.

This classical experiment carried out by Professor Cohen

in 1958 is re-staged here with some of the original drivers.

It's very nice anyway. It was the best wasn't it, Teachers?

The atmosphere was convivial but the alcohol intake carefully monitored.

Some must drink little or none

Others must drink three generous doubles,

three-quarters of a pint of whisky and soda.

Now for the test itself.

And drunk or sober, this bus driver is confident

of his skill, and rightly so, for after three doubles,

he can still get through a gap only a few inches wider than his bus

In fact, he can do this at speeds of up to thirty miles an hour

but when the gap is quietly narrowed to become less than

the width of the bus, the driver with six whiskies inside him

still drives straight through it.

The sober driver, by comparison judges the gap correctly.

He wouldn't even dream of trying.

Professor Cohen's work provided firm evidence that

alcohol seriously clouded judgment.

It might seem blatantly obvious today that there's

a link between alcohol and dangerous driving, but back in the early 60s,

drinking and driving was firmly rooted in British culture

and scientists thought that the best way to change that culture

was evidence, to actually show people just how dangerous

drinking and driving really was but what they failed to appreciate

was just how slow people and society would be to act on that evidence,

and that has become a recurring theme in the history of road safety.

It took until 1966 for the first significant victory

in the battle against drink-driving.

The Road Safety Bill made it an offence to drive with

over 80mgs of alcohol per 100cc of blood.

And to help the police enforce the new law,

scientists invented a portable device that could tell you

whether a person was over their limit on the spot.

A large Scotch, please.

You could even buy one yourself

Next week, do-it-yourself breathalyser kits

will be on sale all over the country.

The idea behind them is that if you drink and drive,

you'll want to know if you're legally fit to do so

To start with, there will be two kits on sale to the public.

The Drink-O-Meter is imported from America

and will cost three shillings.

The Alcolor, made in Cheltenham costs five shillings

and it works exactly like the police model,

the Alcotest 80 imported from West Germany.

It's the only official one and you can't buy it over the counter.

It works like this...

After the sealed ends of the tube containing yellow crystals

of potassium dichromate are broken off, the plastic bag is

attached to one end of the tube and the rubber mouthpiece to the other.

When you blow through the yellow crystals,

they turn green above a white line if you've had too much to drink

A little tricky to demonstrate in black and white

In the first four years, the breathalyser saved some

5,000 lives and 50,000 injuries on the roads.

Politicians were pleased.

It seemed we were making real progress in preventing accidents.

Scientists, however, were not so impressed because despite the

decrease in casualties, alcohol was still the major killer on the roads.

Even after the Road Safety Bill at night, two out of three road

fatalities contained more than the legal limit of blood alcohol.

With little chance of being caught, most drivers simply ignored the law.

It was becoming abundantly clear to scientists that

changing human behaviour, even with new laws,

was more challenging than anyone had anticipated so in the 1970s

when there were still around 7, 00 people dying in car accidents

every year on the road, they began to take a different approach.

If you can't change the driver

then why not change the environment in which they're driving?

Bucknalls Lane junction near Watford, an accident black spot

Dick Rainbird heads a team which has been pioneering low cost

highway improvement schemes here in Hertfordshire.

Problem is, with traffic backing from traffic lights a quarter

of a mile away and obstructing the junction in front of us, and drivers

wishing to avoid this queuing traffic turn into this left-turn lane,

but instead of turning left, then drive straight through.

We've had about seven injury accidents here through

this in the past twelve months

So, what are you going to do about it?

Well, this is where, by engineering changes,

we shall make it impossible for a driver to drive straight through

as we have done, bring the bollards out

and construct an extension to the small island in the side,

and together with carriageway markings,

make it absolutely clear that drivers

should not be making the manoeuvre that we've just performed.

And some of the most promising accident prevention schemes

are often effective, despite the fact they seem perverse.

Mini-roundabouts make drivers feel uncertain

and so they drive more safely.

These simple blobs of paint have reduced accidents

drastically in places.

The same is true of no right turns.

They may be an apparent inconvenience

but they're highly effective road safety devices.

Right turns are the most common cause of collision in Britain.

Environmental engineering was employed all over the country

to make the roads as foolproof as possible.

Over the years, these methods have been continually refined,

making it harder to make poor driving decisions.

Preventing accidents is the ultimate aim of road safety

It certainly seems to be the most logical way of reducing deaths

but logical doesn't necessarily mean easiest or best or only.

There was an alternative approach - accept that humans make mistakes,

accept that crashes are inevitable, so instead of trying to

stop them happening, concentrate on making them more survivable instead.

Scientists now know that crashes don't consist of just one event

In fact, in any collision, there are three separate impacts.

But in the 1950s, it was the first of these, the primary impact

between your car and something else, that drew scientists' attention

When two things collide, their kinetic energy,

the energy they have because they're moving, is released.

It's this release of energy that bends and breaks,

and makes the harmless suddenly deadly.

Simple laws of physics told experts that in order to survive this

first impact, it is crucial that the structure you're

sitting in absorbs the energy before it reaches you...

..and the first effort to apply that idea was made in the late '50s

A Mercedes engineer, Bela Barenyi, came up with a safety concept

that would completely change the design of cars.

Conventional wisdom held that the tougher the body, the safer the car.

But Barenyi understood that if the body was too strong,

the impact forces were transferred from the exterior to

the interior with deadly consequences.

Barenyi re-engineered and he reconsidered the whole issue

and he said, well, if we provide crumple zones, together with a very

rigid passenger cell, this would prevent injuries and fatalities

Bela Barenyi recognised that if the front

and back ends were built to crumple, most of the impact forces would be

absorbed by the outside of the car before they reached the passengers.

And if the inside was surrounded by a rigid frame

it would shield the passenger space.

Well, I think it was a revolution

because now we started to re-engineer the car completely

This is Barenyi's concept in action.

The damage to the car is severe but the passenger space remains intact.

The secret of this design lies deep within the car frame

Marked in red, the skeletal members are made of special materials

that crumple in predictable ways.

This cross-member tightens together,

links the two front members,

and the energy is absorbed while this crumple zone is deformed.

And the energy is deformed outside of the passenger compartment,

and there's no intrusion in the passenger cell at all.

And, do you see this car has a substantial damage

and, if you look here, it has been pushed rearward?

The front end is almost damaged to the half, but I'm really happy

with this damage because it relates to energy dissipation,

and as long as you crumple in the front end, you do not crumple

in the interior space, and that's what protects the occupants.

Barenyi's concept is universal

All makes of car now have crumple zones.

All system clear.

Counting down.

This energy-absorbing design successfully neutralises

the primary impact in any crash

It does little, however, for the next stage of the crash -

what is called the secondary impact.

When a car crashes, it decelerates rapidly,

but the occupants keep on going at high speed...

..which means they impact with great force

against the inside of the vehicle.

And this shows what happens

when your car is stopped by a collision...

..and you keep going.

Crash investigator Don Huelke was all too familiar

with the consequences of the secondary impact.

Here we have an automobile in a head-on crash with a tree

and you can see that the steering wheel's well out of position

and the individual then catches up to it,

bends the steering wheel and put his face here on the centre of the hub,

causing massive crushing of the bones of the face

on the left side of his lower jaw and also of his nose.

Here, for example, is another case of the same sort of thing.

Here, the unrestrained driver moves forward,

gets to the steering wheel, collapses the top part of the wheel rim,

now exposes the rigid hub of the steering wheel

that gets him in the chest

to cause the significant, serious, debilitating injury.

From the brain injury point of view,

it's caused a whole new category of brain injuries that are due to

the extreme violence of the crashes that occur, the tremendous

amounts of energy that are input into the head from the violence

of the car crash - something that never existed before the automobile.

It soon became clear that

it was this secondary impact that was the greatest threat to life

so it followed that if scientists could make that

stage of an accident survivable thousands could be saved,

which sounds simple, but the reality was anything but.

In the early 1960s,

although crude crash test mannequins were used in testing,

scientists didn't know what the forces they measured

meant for the human body.

So the first task would be to investigate

the limits of human tolerance

to figure out how much force the body could take before it broke.

Many in the motor industry

still claimed crashes would never be survivable.

But research at Wayne State University in Detroit

proved them wrong.

Faced with the epidemic of head injuries,

these safety pioneers decided to study how skulls fractured.

And however distasteful it was to many,

they decided they needed to test real human corpses.

In a disused lift shaft, dead bodies were dropped onto a metal plate

Over the next 30 years, cadaver tests, mainly in America,

played a crucial role in building a complete map

of the human body's tolerance to injury.

Well, the bodies were not too difficult to get,

as long as we didn't want very many of them.

The bodies were donated for research at the med school

and they used them for anatomy studies and teaching.

And, of course, they had first call on the bodies.

The embalmed corpses were fitted with instruments to record

the precise movement of the head as it hit the metal plate.

We put accelerometers on the back of the skull,

and with the acceleration we could tell what the force was.

It's a type of job that is not very pleasant,

but after a while you get used to it.

And it's not very pleasant, I suppose, to operate on somebody,

but surgeons do it all the time

So we got used to it and suffered through it.

The head drop showed how much force it actually took to crack a skull

and cause brain injury.

The thing that surprised me

was how much the head could take without being fractured,

and we found that, oddly enough

the head can take a very high force

before it is seriously injured about 400 Gs,

which represents probably a tonne and a half,

but only for very short times.

We're talking about thousandths of a second,

and then it can stand a much lower force for a longer time.

Larry Patrick and his team gathered their findings

and created a graph showing what forces and over what duration

would cause damage.

Provided the impact to the head was below the curve,

they knew there would be no brain injury in a car crash

If we could determine that human head could take 1,200 lbs

for ten milliseconds,

then we could design a car so that that would be the maximum force

that would be applied to the head.

Unfortunately, Larry Patrick's research

was not immediately applied to improve car design.

Back then, reduced head injury didn't sell cars.

Style did, and style often conflicted with safety.

MUSIC: "Louie Louie" by The Kingsmen

It seemed that the public wanted a fast, fun car,

even if it killed them.

# Louie, Louie... #

In the early '60s,

most manufacturers did little to soften obviously lethal features.

In those days, the vehicles were very hard inside.

There were no padded dashboards there were knobs that stuck out

to control the radio and the gear shift lever.

The windshields were very stiff and hard.

The header where the windshield and the roof come together

were very stiff, and so when the head hit those structures,

we got a lot of skull fractures

a lot of bruising of the brain subdural blood clots,

epidural blood clots such as this,

where there's a lot of damage in one spot.

In order to find the blood clot at that time, numerous holes

had to be drilled into the skull, first on the one side

and then if nothing was found, on the other side,

and if nothing was found on both sides, you hoped that

there wasn't one hiding in between the holes someplace

SIRENS WAIL OVER CHORAL MUSIC

By the mid '60s, cars were killing 60,000 people a year in America

In Britain, someone died on the roads every hour.

The politicians were beginning to lose patience with the manufacturers,

so General Motors contracted Wayne State University

to do more research into how the whole body was injured in crashes.

So began another series of gruesome experiments on the dead.

We studied impact to the head, to the chest, to the knees,

any part of the body that could be injured in the automobile.

As Larry and his team were now looking at not just head injuries,

but the entire human body, they had to make sure

the results from the cadaver experiments

were giving an accurate picture of what a living human could tolerate,

and for that they needed volunteers.

I was the volunteer.

It was a matter of, I was in charge of the lab

and if anybody got hurt, I was responsible.

I figured if I hurt myself, that was one thing,

but I didn't want to take a chance on hurting anyone else.

Felt like being hit in the chest with a sledgehammer.

It actually knocks me over backwards quite a ways.

Over the next few years, Larry continued to study the biomechanics

of the human body, usually involving experiments on himself.

Well, it was his work,

but of course there's always the danger of something happening to him

which I was not comfortable with,

but that was his affair.

She was... She's mellowed a lot now.

It was much more intense at the time.

SHE LAUGHS Yes.

By the time Larry Patrick had finished self-experimenting

he'd provided us with a detailed picture

of what kind of forces caused injury.

The tolerance and limitations of the human body

had finally been revealed.

For the first time, scientists could attach some meaning

to the forces that crash test dummies measured.

If they exceeded the Wayne State human tolerance curve,

it meant the force could be fatal.

And, armed with this new knowledge, more and more engineers

embarked on developing ways to guarantee protection in an accident.

Across the world, engineers churned out life-saving equipment

that could help improve the chances of surviving

the killer secondary impact. However, it became clear

that ingenuity and good design wasn't enough.

The biggest challenge would be persuading manufacturers

to install them and people to use them,

and tragically, the longest and most bitter struggle

centred around the application of the greatest life-saver of them all.

Six, five, four,

three, two, one, go!

The modern seat belt was invented by Volvo

and first fitted to their cars in 1959.

But, for several years, few other manufacturers offered

the crucial combination of lap and chest restraint.

Many cars were still just fitted

with a two-point belt across the lap.

We saw in the accidents where two-point belts were used

that there was still a high risk of impact on the occupant

towards dashboard, for example by the head or chest area,

and the only solution to that problem

was to add also a shoulder portion of the belt system,

and since the shoulder belt is lying on rigid parts like the rib cage,

we felt very confident that there was no risk introduced with this system.

It was THE greatest advance in making crashes more survivable,

but although Volvo embraced three-point seat belts,

the rest of the industry was reluctant to install them.

The majority of the public didn t know what they were missing,

so with little consumer or political pressure,

manufacturers ignored a life-saving opportunity.

Then in the mid '60s, an idealistic lawyer in America

began sifting through reports on unused safety features.

His anger would spark off a chain of events

which would change car safety forever.

As a law student at Harvard Law School, I came across

some of the research writings, and I was stunned.

I realised that there were a lot of life-saving safety devices

on the shelf in Detroit that engineers had built

and innovated over the years, like seat belts, like head restraints,

that were never put in cars. And I began to ask why.

Why were they selling style and they weren't selling safety

In 1966, after Ralph Nader published a bestseller

on the dangers of American cars he was called to the Senate

to testify at a special hearing into deaths on the roads.

General Motors were one of his main targets, and the car giant responded

by hiring a private detective to dig up dirt on this unknown young lawyer.

But their attempt to discredit Nader backfired.

The detective was exposed

and the president of General Motors was called in to explain.

I want to apologise here and now

to the members of this sub-committee and Mr Nader.

I personally have no interest whatsoever in knowing

Mr Nader's political beliefs, his religious beliefs and attitudes

his credit rating, or his personal habits

regarding sex, alcohol or any other subject.

It was a great news story and the publicity made Ralph Nader

a national hero whose words now carried great weight.

Many, many safety features sometimes cost only pennies more

and many times cost less.

A couple of examples,

this collapsible steering shaft by GM costs them no more

once they retool for it than their other type of steering shaft.

The safer instrument panels, and instrument panels today are killing

between 5,000 and 8,000 people by being struck against them,

a safer instrument panel is actually cheaper to manufacture.

It provided a lot of public attention

and force behind the passage of the first

comprehensive motor vehicle safety law in American history

Surviving the secondary impact was no longer an impossible dream

and instead of being some kind of industry secret,

it had now become public knowledge.

From January 1967, cars had to meet 22 new safety standards,

covering everything from the steering column

to the rear view mirror,

and front seat belts now had to be fitted by law.

Europe soon followed with similar crash protection standards

and, in the early '70s, for the first time,

deaths on the road started to fall.

But the public seemed determined to undermine the engineers.

They just wouldn't wear their seat belts.

There were all sorts of myths out there.

"I'd rather be thrown clear in a crash

"than wear a seat belt that will tie me in."

People thought that you might get a broken neck

if you're wearing a seat belt.

"If the car goes into water, I'll drown

"because I won't be able to get out."

People thought that if they had a crash,

cars go on fire all the time and you wouldn't be able to get out.

And today it just seems ludicrous

that people would be thinking that way,

but we're talking 35-40 years ago. That was the thought.

There were all sorts of scare stories around like that

which probably had enough influence

to delay people really thinking about it rationally

and using the research knowledge that was coming along

as early as they should have done.

So, although the battle against manufacturers had been won,

now the fight was about getting people to use the very things

that could save their lives.

It was particularly tricky in America,

where they felt that making seat belt wearing compulsory

would be an infringement on personal freedoms.

Reliable crash protection can't depend on human cooperation.

It has to be built into the car

and it has to work when it's needed, automatically

So, engineers went back to the drawing board to develop a device

that could save people who didn't want to save themselves.

The air bag.

The air bag is a revolutionary concept in passenger protection

and requires a very complex system to be installed in the automobile.

We have several components. First, a high pressure gas cylinder,

which is basically the energy source for inflating the air bag.

The gas is then distributed to the air bag

through the slots in the manifold.

The air bag is rolled around the manifold

and located underneath the instrument panel

and behind the instrument panel

And, as you can see from the size of the air bag,

it's large enough to protect the front two occupants.

In order for the air bag to be effective,

we must inflate the air bag in one-twentieth of a second.

In the early days, there were many problems to overcome.

They had to fill with gas at the instant of impact.

Sometimes they used too much explosive,

and the air bag blew apart.

Or it was too large to inflate properly.

Eventually, they perfected the art of explosive inflation

Humans were also tested

to ensure they could withstand the explosion without hearing loss.

Once the air bag was refined,

this was one design manufacturers were prepared to install,

and from 1980, they became more and more commonplace.

However, most safety experts knew

that although air bags improved survivability,

they would never surpass the life-saving capabilities

of the seat belt.

And, in this country, eventually the penny dropped for the public too.

A powerful catalyst were those grim pictures

of Alex Blackhall's needless death broadcast on the BBC in 1981.

His wife, or rather his widow,

has consented to these scenes being shown.

They might, she hoped, do some good.

The programme intensified the debate about compulsory seat belts.

Public opinion started to shift

and, in 1983, wearing front seat belts

finally became a legal requirement.

During this morning's rush hour in London,

the vast majority of drivers and front seat passengers

were securely fastened.

It seems the fear of prosecution was a greater incentive to belt up

than all those previous seat belt campaigns

with their appeals to reason.

Good morning, I see you're wearing your seat belt today.

That's correct, yes. Is this simply because of the law?

Indeed, I've never worn it before. I prefer to be free when I'm driving,

but I'm aware that the law want me to enforce things today

so that's why I'm wearing it.

The effect was dramatic.

Instead of falling gradually, road fatalities started to plummet.

And a second big drop was witnessed eight years later,

after the rear seat belt law came into force.

The annual fatality figures fell to an all-time low of around 4,000

By the late 1980s, huge strides had been made

in making crashes more survivable,

but another problem was becoming apparent.

Scientists realised that in any collision,

there was actually a third impact,

and this was the most complex and least understood stage of the crash,

because it happens inside the body,

which is why it became known as the hidden killer.

ALARM BEEPS

The third impact comes when your body stops moving

but your insides don't.

Just as you might hit the inside of the car,

your organs will collide with your skeleton.

But without the ability to see inside a living person

in crash conditions,

scientists knew little about the internal consequences.

That was until the 1980s, when medical research stepped in

and revealed something that would completely transform your chances

of surviving a crash.

One, two, three.

We have, approximately - we'll say 25-year-old female,

this is a motor vehicle accident, car versus ditch.

By the early '80s, the nature of head injuries was changing.

Air bags and seat belts had cut down skull fractures,

but one form of lethal injury

was being replaced by something more mysterious.

..I would say that's probably been 30 minutes ago.

Accident victims were still dying in comas,

but now nothing was showing up on the brain scans.

Initially we were very depressed,

because we knew the brain is injured

and when we went out to talk to families about this,

we'd say your son is in a coma

he has bad brain injury,

and the families would say, "Well, what is the injury?"

And we would look at one another and say,

"Well, we don't exactly know, but we know the brain is badly injured,"

and we'd look on the CAT scans and, and find virtually nothing,

sometimes a little drop of blood, but hardly anything.

At their laboratories in Philadelphia, Dr Gennarelli's team

decided the only way to understand this invisible killer

was to reproduce the injury in an animal.

In the early '80s, they performed a series of experiments on monkeys.

This was the price to be paid for understanding head injuries

but the experiments sparked fierce protests

from animal rights activists.

The research's aim was to put a baboon in coma.

The system that we were using that produced the injury was

the animal head was never impacted.

It was encased in a helmet.

The helmet was attached to a linkage

and the linkage was programmed to move at a certain velocity

over a short distance so there was no loading of the neck,

but we could rotate the head in different directions

at different velocities.

They discovered that no kind of forward movement

ever resulted in coma, but shaking the head sideways

produced dramatically different results.

As soon as we produced a rotation in the lateral direction,

the animal was in coma.

That first animal, we studied for six weeks in coma.

No-one had ever produced coma in an animal model.

The brain is made of two hemispheres

connected by nerve axons which run between them.

Slamming the head sideways pulls one hemisphere away from the other,

dangerously stretching those axons.

What we've got here are some axons.

They look pretty bad.

When they looked at the nodes from this section of the brain

under the microscope,

they had expected to find the axons stretched to breaking point,

and severed nerves meant permanent brain damage or death

Then a great revelation took place.

People had the notion that at the instant of an impact to the head,

there was a damage resulting from tearing of neurological material.

And what we knew at that time about central nervous system tissue,

that was irreversible, that that was final.

Instead, what we found, I think to the surprise of many

was that the axons were indeed stretched, but they weren't torn.

The stretching seemed to make the nerve axons slowly swell up

and balloon out, eventually destroying themselves

in a gradual process that only started hours after the impact.

Suddenly there was an extraordinary medical possibility.

If most of the damage happened hours after the crash,

then perhaps drugs could be developed to stop the nerves swelling

in time to save thousands of lives.

We now know something that is very precious that we didn't know before.

We thought there was no influence that we could possibly have,

no treatment, no therapy, no surgery that would influence this

because it was all completed,

and now we know that that's not true,

that the degeneration in the brain is progressive.

It was a truly ground-breaking discovery.

It meant that as long as patients received expert treatment

before their brains started swelling,

coma and death could be avoided

So, today, surgeons are working hard

developing ways to get to their patients as quickly as possible

so they can protect the brain and salvage neurons.

For trauma medics dealing with car crash victims

with suspected brain injury, speed is now everything.

Here in Miami, two helicopter units

are on constant readiness for action.

They can be scrambled in an instant

and recover a patient within minutes.

Their destination?

Jackson Memorial Hospital,

where trauma medicine is undergoing some radical changes.

What's the story? He was involved in a motor vehicle accident,

he was unrestrained, hit the windshield, major intrusion.

Head injury.

This is trauma medicine as you might never have seen it before.

Going into room two.

To speed up diagnosis and treatment,

this new technology is being trialled here for the first time.

What's your name, sir?

Javier...

Javier? Yeah.

What happened to you, Javier?

This is advanced telemedicine.

For medics dealing with time-critical injuries,

this robot brings rapid advice from afar.

From a remote location,

Dr Antonio Marttos controls the robot bearing his image.

How are the vital signs right now?

He is able to communicate directly with the team

at work in the trauma unit.

OK, got to see his head right now.

By controlling cameras on the robot,

Dr Marttos can make a rapid diagnosis

and talk the resuscitation team through advanced procedures

which might be needed straightaway.

He has a bad laceration, probably has a really bad head trauma.

Yeah, this is really bad, OK.

Providing fast expert treatment like this for car crash victims

will save time and lives.

But today there's a surprise in store.

This car crash victim is making a remarkable recovery,

and not because of the ground-breaking

telemedicine technology.

LAUGHTER

This is an important training exercise for the hospital.

With great attention to detail

the medics have used a typical car crash scenario

to test the effectiveness of this new telemedicine system

I can really support the physician or the nurse

from long distance

and help them to have the best expertise available always.

Doctors hope this telemedicine project

will begin a new era in trauma medicine.

It could forever improve your chance of surviving brain injury

in a future car accident.

Understanding and controlling the outcome of any third impact

inside the head has come on in leaps and bounds since the 1 80s.

A huge achievement, considering it was once the hidden killer.

Scientists and doctors and engineers have all been instrumental

in helping make our roads safer

and improving our chances of surviving a crash,

but we're still stuck at around 2,000 fatalities a year,

which got me thinking, what else can we do to save lives?

And it seems, increasingly, the answer may lie with computers.

Today, cadaver and animal research

can be time-consuming and controversial,

and traditional crash test dummies

aren't good at replicating internal injuries.

So scientists have been developing a new type of virtual dummy

which will tell us what happens to all of the vital organs

inside the body during all types of car crashes

It is a monumental task,

the biggest coordinated research effort in car safety history.

And it starts with the human body itself.

What makes this project so special

is the unprecedented attention to detail.

Beginning with individual cells in the body

and working upwards from there

scientists in labs worldwide are working out the maximum force

that every part of the body can take before irreparable damage occurs.

Here, they're studying the abdomen.

I'm using a template

to position pressure sensors that will be placed inside the liver

so that we can measure internal liver pressure.

This type of testing isn't just limited to the liver.

We do this type of thing

for all the internal organs of the body,

specifically the solid organs, so we look at liver, spleen, kidney,

any of those organs in order to determine its tolerance to loading.

By gathering such detailed information about the forces

that every single part of the body can withstand,

scientists will be able to update existing dummies

with a brand-new model.

But it will be a dummy with a difference.

A virtual dummy.

The human body model.

There are a number of reasons to go toward that type of model

as opposed to the physical model.

In the virtual world, we can do a lot more for a lot less.

It's hoped that virtual dummies will revolutionise car safety.

They will be able to predict

the exact moment crash forces become too much

for people to cope with.

Virtual models of the human body

hold the promise of truly understanding what happens

inside our bodies during car crashes.

But computers aren't just helping us

understand the consequences of a crash.

For over a decade there's been a growing hope

that they could also prevent accidents from happening

in the first place, tackling the age-old problem of human error

In the future,

perhaps drivers will be able to put their cars on autopilot

and let computers take the strain.

This row of cars in California are all travelling at 60mph,

exactly 21 feet apart, under computer control.

A ride on this automated highway

begins when the car takes over from the human.

AUTOPILOT: Speed control on.

Steering control on.

Foot off the pedal,

hands off the wheel,

and the ride begins.

Part of what we're doing

is trying a whole bunch of different technologies.

Some of these systems rely on computer vision,

some of them rely on magnets buried in the road,

some of them rely on special lane marking strips that reflect radar.

Magnets in the centre of the road enable the car to track a course,

and automatically adjust the steering control.

Radar screens on the front and back of each vehicle

maintain a safe distance between the cars.

If something unexpected happens like a breakdown,

the automated truck detects the car ahead with plenty of time

to change lanes.

Since 1998, many of these computer systems

have already made their way into our cars,

like proximity sensors

and automatic braking systems.

All of them work to help the driver avoid crashes,

and the fully autonomous car may not be too far off.

Several different driverless car systems

are now being tested on public roads.

Some engineers feel sure that by taking humans out of the equation

and completely handing over the controls to a computer

the crash rate will decrease even further.

But I can't help feeling that once again it may be the consumer

that proves the biggest barrier to the driverless car.

It is just astonishing how far we've come in making road travel safer.

Scientists and engineers have worked exceptionally hard to save lives,

but what I find extraordinary

is that those scientists were also campaigners,

fighting to have their inventions and their knowledge

applied to the real world,

when manufacturers, politicians and ultimately us, the general public,

remained strangely, well, resistant to having our lives saved.

# I don't wanna die

# In a car crash with you

# Tonight

# The roads are wet

# And you're asleep at the wheel

# Open your eyes

# Open your eyes. #

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