In November 1957,
Britain exploded its first megaton hydrogen bomb...
..over 100 times more powerful than the one dropped over Hiroshima.
This is the story of an extraordinary scientific project,
which, against almost insuperable odds,
made Britain a nuclear superpower.
It is told through unprecedented access
to Britain's top-secret nuclear research facility at Aldermaston...
..including the only interview ever by the man who was, for decades,
this country's bomb-maker-in-chief.
Here we have the first hydrogen bomb
that went into service with the RAF for the United Kingdom.
With archive footage and photographs
especially released for this programme...
This is the very, very early stages of the weapon going off,
running at about 125,000 frames a second.
..including interviews with scientists and veterans,
many speaking for the first time.
A bomb came loose whilst the aircraft was flying over Dorking.
He said, "Well, the government's just announced that
"we're going to make a hydrogen bomb.
"We don't actually know how to do it. Have you got any ideas?"
This is the inside story of how Britain's bomb was built.
OVER RADIO: 'Copy. Receiving you loud and clear, over.
'Minus 25 seconds. 203.'
On November 8th, 1957,
an RAF bomber was flying to Malden Island
in the middle of the Pacific.
It was carrying a bomb that would transform
Britain's place in the world.
'Telemetric to Internal. Minus 20 seconds.'
It was a mission fraught with danger.
We were flying between 40,000ft and 50,000ft
and we were given the clearance to go ahead.
'Bomb doors open.'
The actual point that the bomb had to explode at
was at 8,000ft and several miles off the island
over the sea.
'Minus 10 seconds. 202. Steady.
'Steady. Steady, steady, steady. Bombs away.'
At 17.47 Greenwich Mean Time,
the Valiant bomber dropped its payload -
a massive hydrogen bomb.
The crew then had just one minute to escape the blast
with a sharp 140-degree turn.
When we did release the bomb, we had to do a quick getaway -
we called it an escape manoeuvre - away from the danger zone,
so that the bomb didn't explode immediately underneath us.
My job, as a co-pilot, was to monitor an accelerometer
which told the captain how much
G-force he could pull without the aircraft stalling.
In the event,
as we rolled into this tight turn,
a wire broke off at the back of the instrument
and so I wasn't able to tell the captain
he was getting near the limits of how tight a turn he could do.
And at that instant,
the aircraft started to bounce around
as though we were coming to the stall,
and the engines also started to have a little bit of a burble,
which meant that things were not quite right.
The bomb aimer was thrown back into the nose of the aircraft
by the extra G-force placed upon it.
It was dangerous. We didn't have time to think of,
"How have we got to get out of it?"
It was just pure flying skills to correct the stalling
and we just turned as hard as we could go
and head away from the explosion.
It was a close run thing,
but the Valiant escaped from the blast zone.
EXPLOSION
The implications of this explosion continue to reverberate to this day.
For better or worse, by developing its own hydrogen bomb,
Britain had forced its way into the elite group of nuclear superpowers.
It was the culmination of an extraordinary story
of British scientific endeavour...
..which began 40 years earlier with this man, Ernest Rutherford.
In our laboratories today, we live in an atmosphere
dim with the flying fragments of exploding atoms.
And on this occasion...
In 1911, he discovered the atom,
the fundamental building block of every element in the universe.
It soon became clear that if scientists could split the atom,
it had the potential to release huge amounts of energy
in a nuclear chain reaction.
So, American scientists began building huge machines
called cyclotrons to produce the several million volts
they thought would be necessary to split a single atom.
In Britain, one physicist, John Cockcroft,
had a different plan.
My father thought there was a probability
that it could be done at a much lower voltage
and he calculated
300,000 volts instead of the several million
and he then took those calculations to Lord Rutherford.
Rutherford said, "Team up with Ernest Walton
"and build the apparatus to prove that this is true."
And I think, when he saw the opportunity to split the atom,
he jumped at it.
The two men still had to create
their ambitious experimental apparatus from scratch.
It was very Heath Robinson-ish.
The box down at the bottom where the observations were made
was, I think, constructed out of old tea chests.
It must have been a bit cramped in there,
though my father never actually remarked on how cramped it was,
except when he mentioned that he had to try and squeeze Lord Rutherford
into a small box, and he was a big man!
This later version in the Science Museum
shows how the 300,000-volt electrical charge was created.
Well, this is known as the Cockcroft-Walton voltage multiplier
because what it does is it takes a low voltage,
steps it up to the high voltage
that we need if we're going to split an atom.
It's rather like a step of a staircase
with a number of steps.
Charge can flow up one step, then up the next step,
and so on, right up to the very top.
And at each stage, it is building up the voltage,
so at the very top of the machine,
you've got the high voltages that you really want
if you're going to try and split a nucleus.
The apparatus would fire high-energy particles
at lithium atoms
with the aim of splitting them into subatomic alpha particles.
On the 14th of April 1932, Walton switched it on.
And he saw these little sparkles of light.
These photographs captured the results.
We're looking at the paths that are left by the alpha particles
as they speed away from the splitting nucleus.
Now, we can't see the alpha particles themselves -
they're much too small -
but we can see the trails they leave behind.
The atom had been split.
It was a massive British scientific achievement.
Now scientists worked to see if splitting the atom could go on
to start a chain reaction,
which would unleash extraordinary forces.
When an atom is split, it produces smaller particles,
most notably neutrons.
In theory, it was possible these neutrons
would go on to split other atoms...
..so triggering more neutrons, leading to more splits,
creating a chain reaction.
This would release more energy than had ever been dreamt of.
It seemed to be a thrilling prospect.
PLANE ENGINE DRONES
Then, in 1939, war broke out with Germany and everything changed.
Now nuclear research became a matter of life and death
because the scientists knew that it could also be used
for a much darker purpose.
EXPLOSIONS
Scientists in Britain, both British-born scientists
and some of the refugees from Europe, were
very concerned about the threat that Hitler,
that the Nazis would develop, successfully, an atomic bomb.
They themselves started to think, "How was it possible?
"What would you have to do to make this happen?"
Scientists had worked out the major problem to overcome
in order to create an atomic bomb concerned the fuel.
The key material was uranium.
Initially, it was thought that so much would be needed
that a workable bomb was impossible.
But two German physicists who fled the Nazis
and came to Britain thought differently.
Rudi Peierls and Otto Frisch made a breakthrough
by working with a special type of uranium called separated uranium.
From the theory of the fission process,
we couldn't estimate how much you would need
to produce a chain reaction in the separated uranium,
and we were surprised to find how small it was - only a few pounds.
It wasn't the tonnes that one intuitively had guessed before.
This discovery was a major turning point.
It showed that, in theory, a bomb could be built.
And then we said, "It's frightening that the Germans
"might have realised that, too."
And the idea that Hitler would have this weapon
before anybody else got it was frightening.
The discovery meant it was now vital to beat the Germans to the bomb.
Rhydymwyn, in North Wales,
was one of the most secret places in wartime Britain.
These buildings are remnants of a project code-named Tube Alloys -
this country's attempt to build an atomic bomb.
Eileen Doxford was one of the first to work here as a chemist, aged 19.
I was calibrating an instrument every 20 minutes,
but I didn't really know what I was doing.
I was told that only two people knew what we were actually doing
and that we had to just accept
and do the job that we were given as well as we could.
And we had not to discuss it with anybody,
not even your dad!
Eileen didn't know it,
but the Rhydymwyn plant was designed to make uranium isotopes
for the atomic bomb.
The process was designed and supervised by Rudi Peierls.
His daughter Jo remembers the pressures her father was under
to force his technology to deliver.
It was the forefront of science, what they were doing here.
It had never been done before. It had never been tested.
And it was back-of-an-envelope job that they were designing
into something that became a huge industrial process.
I think they were getting quite close to succeeding,
but on the other hand, there was this feeling
they were encountering more and more difficulties
and more and more delays.
Britain's lack of resources,
combined with the continual threat of German bombing,
led to a momentous decision.
In 1943, the Prime Minister Winston Churchill
agreed with US President Franklin Roosevelt
that America should take over the project.
All atomic bomb research in Britain was transferred to the USA.
Britain sent 19 of its finest scientists
to the huge nuclear research facility
at Los Alamos in the New Mexico desert,
part of the so-called Manhattan Project.
One of them was Rudi Peierls,
who was so eminent that he was able to choose who would go with him.
One of the people that he asked to accompany him
was Klaus Fuchs who apparently had the most brilliant mind.
He was called a Calculator
cos he was able to do calculations much better than anyone else.
Fuchs and Peierls formed a very tight bond.
Klaus was one of the family.
My mother had a sort of maternalistic view towards him
and would cook for him and look after him.
Klaus Fuchs had a car.
He would take them off onto various excursions
so they could go further afield with him.
So, there are all these souvenirs from Los Alamos -
little things like this leaflet on hunting and fishing in New Mexico
and also a guidebook of Santa Fe.
I think being in Los Alamos
was possibly one of the most enjoyable things that he did,
because he was able to do all the physics he wanted to,
there were these brilliant physicists that he could talk to
and there was the countryside that they could go and explore,
so they had a marvellous time.
On July 16th, 1945,
Peierls, the man who had first calculated
that a bomb could be built,
witnessed the first ever nuclear explosion
in the American desert.
I think there was a mixture of feelings.
There was a vindication of his science -
that these calculations that he and Frisch had done
on the back of an envelope all those years ago had been right.
It was the first time anyone had seen this mushroom cloud.
There was a feeling of awe as this cloud built up
and they could see the size of the explosion
from a bomb that wasn't really that big.
Within a month, atomic bombs were dropped on Japan,
which ended the war.
The atomic bomb had been the culmination
of a joint effort between the British and American scientists.
But that didn't mean the British knew how to build a bomb.
British scientists came back from Los Alamos
with a lot of knowledge about the nuclear weapon,
but not with a complete picture or anything remotely like it.
They had had a very close look at the detail of the weapon itself,
but they had been excluded almost entirely
from the production processes
that went to making up the elements of the weapon.
So, they were ignorant about,
for example, creating nuclear reactors.
The significance of these gaps in the British scientists' knowledge
soon became painfully apparent.
In 1946, the US Congress passed the McMahon Act,
which prohibited any sharing of atomic information
between Britain and America.
To the British, who'd given so much to the Manhattan Project,
it felt like betrayal.
But in the United States,
many felt enough had already been done
to support Britain during the war.
Senator Vandenberg said, "Well, look,
"we bailed these fellas out to the tune of billions of dollars.
"Why do we have to do any more for them in this very special field?"
There was a lot of congressional opposition
to dealing any further with the British.
So, in 1946,
the new Labour government faced a critical decision.
The Prime Minister, Clement Attlee, chaired a top-secret meeting
to decide whether Britain should go it alone and build a bomb.
The need for post-war reconstruction
had to be weighed against the controversial idea
that, to be a superpower, Britain needed a nuclear bomb.
Michael Perrin was at the meeting.
The Prime Minister summed up very much on the lines of
our country couldn't stand the money to do it,
we haven't got the materials,
with the present crisis in the country and all the rest of it.
And at that stage,
the Foreign Secretary, Mr Bevin came in
and said, "No, Prime Minister, that won't do at all.
"We've GOT to have this."
And, quite bluntly, he said,
"I don't want any other Foreign Secretary of this country
"to be talked at
"by a Secretary of State in the United States
"as I have just had in my discussions with Mr Burns.
"We've got to have this thing over here,
"whatever it costs,
"and we've got to have a bloody Union Jack flying on top of it."
And that swung the meeting right round.
If Britain was going to be a top power,
it was imperative, so far as the British Government saw it,
that Britain should have an atomic weapon.
It was an expensive commitment, but it was all done in secret.
Clement Attlee told neither Parliament
nor the people of Britain about it for two years.
The scientist chosen to lead the British atomic bomb research effort
was William Penney.
He had just returned from working at Los Alamos
and was famously sparing with his words.
Well, I think it's got to be done.
What does your wife think about it all?
Oh, I think she agrees with me.
And in your spare time, in your free time, what do you do,
as a complete contrast to the work that you're doing now?
I usually play golf. You're a keen golfer? Yes, a keen golfer.
From his work at Los Alamos, Penney believed that plutonium,
which could be manufactured from uranium,
was the material for the core of the bomb.
The first problem he faced
was creating the temperatures and pressures necessary
to initiate a fission chain reaction.
For the first time, Britain's chief atomic bomb-maker, Ken Johnston,
explains the principles of the design the scientists settled on.
Penney and his designers decided to go for an implosion system
which would compress a central plutonium ball.
And they did it by surrounding it with high explosives.
And the high explosives had to be set off simultaneously
so that there was a symmetrical implosion...
..which converged on the plutonium wall
absolutely symmetrically...
..and compressed it to many times its original density.
The fission chain reaction built up
and finally the whole thing exploded with enormous force.
That's the principle of the implosion system.
But as Ken Johnston demonstrates,
designing an explosive which could compress the core
was a tremendous challenge.
What we have here is about half a kilogram
of ordinary explosive - the flat end -
and it's powerful enough to blow in the front of a house.
What we're going to do is we're going to place it
on this piece of steel and detonate it,
and then we'll see what happens.
This solid, three-inch-thick lump of steel
stands in for the plutonium core of the bomb.
The aim is to create an explosive charge so focused
that it punches a hole through the steel.
Under fire.
Fire. EXPLOSION
Hmm.
What we can see here is a very shallow depression
when the flat detonation wave has struck the plate
and it's made a small depression in the steel.
Now, to compress a ball of plutonium,
you need to focus the energy to the centre of the device.
And this sort of thing - a flat explosion, slap -
is not going to do the job for you.
For five years, the British scientists worked
with a wide variety of explosives,
experimenting with the materials and the shape needed
for the explosive charge.
A lot of people came to assist
with the high explosive end of the business,
casting and machining and forming the explosives
into the correct shapes to produce the implosion system.
They came up with a design that produced
the necessary temperature and compression.
This is a small-scale version of that explosive charge.
What we have here is a fast detonating explosive
and a slower one.
This is the slow explosive
and it is shaped to mate up with the hollow curve
of the fast detonating explosive here.
The two fit together,
and the combination of the two makes an explosive lens.
This is now going to focus the energy
right on the centre point of the detonation.
Fire. EXPLOSION
Well, you see, the whole thing has bounced and flipped right over.
But if we look at the face exposed to the explosive,
you'll see that it's a very sharp hole indeed
which shows you how well the explosive charge
has focused its energy to produce
this very deep hole in this piece of steel.
And you can see it goes in quite a long way
and it's heavily focused now on the very central area.
So, the scientists now knew how to create the explosive lenses
to detonate the bomb's plutonium core.
It was just a case of scaling up the design.
It required half a kilogram of high explosive to produce this effect,
but the first atomic bomb that we built
had two tonnes of high explosive in it
to produce the convergent shock and compress the central plutonium.
While scientists worked to build the bomb,
a group of engineers confronted a very different set of problems.
This is Orford Ness,
a desolate stretch of shingle and stone on the East Suffolk coast.
It's here that bomb engineers like Reg Milne
tested the bomb's release and targeting systems.
He was part of the top-secret Royal Aircraft Establishment
and has come to meet a colleague, Professor John Allen.
Hi, Reg. Hello!
It's the first time they've met for more than 50 years.
Yes, many, many years. I think it was '61.
Yes. We were in the same building, weren't we?
But we were... In different worlds. Yes.
And we were not able to talk... No. ..about what we were doing.
Yes, that's right.
It was this need-to-know, top-secret world. Absolutely.
This footage of Reg with the bomb has never been seen before.
He had to address a serious problem with the release mechanism.
One flight to Orford Ness, a bomb came loose
over Dorking. It fell off its hook.
Luckily, the bomb doors were strong enough to hold it,
and the pilot took the aircraft over the Thames Estuary,
opened the bomb doors, the bomb fell out,
and the splash nearly drowned a couple of sailors
who happened to be nearby. They never found it.
It's still under the Thames somewhere.
Fortunately, the bomb was a dummy,
with no explosive or radioactive material.
But there was another issue that was harder to solve -
the atom bomb weighed less than a conventional device,
which meant that, when it was released from the bomb bay,
it could be lifted by an updraught of air
flowing under the aircraft fuselage.
If you didn't watch it,
the bomb could climb back up into the bomb bay
because of the forces on it
and that, of course, was the last thing you wanted to happen.
You know, they had various fuses on them,
and if they hit something, it would have gone bang.
I mean, it was a really critical...
We used to have the phrase...
You're doing a job and you get a stopper.
And this was a stopper that could have stopped it dead in its tracks,
and we had to make it work.
But John Allen came up with an ingenious solution
to ensure the bombs dropped down and not up.
We fixed these dragon's teeth.
They were a series of flaps underneath,
and when the bomb bay doors opened,
these were then able to be pushed out
and this changed the airflow
and diverted the flow not upwards but outwards,
and that sucked the bomb nose down.
And that really killed the problem at source,
and it killed it very effectively.
People who can handle this chaotic process
of sucking it and seeing it,
not knowing whether you've got a solution -
that is real engineering.
By 1949, Britain's bomb scientists were making good progress,
but then came a devastating double blow.
President Truman has announced the perfection
of an atomic explosive by the Soviet Union.
The Soviet Union had exploded an atom bomb
named Joe-1 after its leader Joseph Stalin.
The British government, like the American government,
was simply astonished
when the Russians successfully tested a nuclear weapon.
There was shock and there was terror.
The threat was at the door
and Britain had to have a bomb of its own as soon as possible.
But the second blow was even more catastrophic.
The Americans had uncovered a series of telegrams
which revealed that a British scientist,
who'd worked at Los Alamos
and was now at the centre of the British atomic establishment,
was a Soviet spy.
Klaus Fuchs.
Fuchs had been absolutely at the heart of planning the wartime bombs.
He'd also been a key adviser to Bill Penney
on making the British bombs.
He had given the Soviet Union lots and lots of information
to help them develop a bomb,
and they must have owed a lot to Klaus Fuchs.
Fuchs was arrested, but the damage was done.
Politically, it was a disaster.
There was a human cost, too.
Fuchs had been the protege of Rudi Peierls
and they'd worked together at Los Alamos.
The Peierls family were devastated.
I think they were hurt
in the same way that if anyone in your family betrayed you,
you would be hurt.
My mother wrote to him a letter, and she said to him,
"Do you realise what will be the effect of your trial
"on scientists here and in America?
"Do you realise that they will be suspected
"not only by officials but by their own friends
"because if you could, why not they?
"Oh, Klaus, my tears are washing away the ink.
"I was so very fond of you.
"This letter is just a sea of ink."
His protege's spying had dreadful ramifications for Rudi Peierls.
For my father, there was a whole stigma associated with it
and it affected quite a lot in his work.
But after he died, somebody published an article
that said that my parents were spies.
I had probably a millisecond of time when I thought to myself,
"Well, maybe he was guilty."
And that millisecond of that,
I will never forgive the authors of those article for,
because he was such a truly great man,
he was such an honest man,
that it was wrong that I doubted him and I shouldn't have done that.
And for the British government,
the timing of the Fuchs expose could not have been worse.
The British never stopped trying to persuade the Americans
to resume cooperation,
and after the news that the Russians had the atomic bomb,
they felt they were making progress.
There was a certain softening going on.
As soon as it was revealed that Klaus Fuchs had been spying,
and the scale on which he'd been spying,
the Americans simply pulled up the drawbridge.
That was the end of it.
The door slammed because they were certain now
that Britain could not be trusted with nuclear secrets.
The need for Britain to create her own atomic bomb
had never been more urgent.
So, in 1950, work began at Aldermaston in Berkshire
to create an advanced centre for Britain's nuclear weapon research,
known by some as the bomb factory.
It had new laboratories
and many of the country's brightest scientists came to work here.
Each department had its own speciality,
but it didn't know what the others were doing.
There was a need-to-know principle,
so there was a great deal of rumour-mongering went on
about what they were doing over there.
So, it was a very strange but exciting environment to be in.
Now in the secure Aldermaston site,
the science team were wrestling with the dangerous task
of shaping the plutonium core of the atomic bomb.
Plutonium doesn't occur in nature. It has to be made in a reactor.
It's an extremely dangerous metal. It's radioactive.
It is very toxic, so, if you ingested it,
it will go into various parts of your body and irradiate it.
You really don't want more than a microgram ever to escape.
A millionth of a gram is bad news, so it is that toxic.
And if you assemble too much of it in one place,
you will have a chain reaction which will throw it apart
and produce a flash of radiation
which will kill most of the people within a fair distance of it.
Not immediately, but over a few days.
So, it's extremely dangerous stuff
and has to be treated with extreme care.
William Penney played a key role
in solving the problems of shaping the core.
But there were those who suspected he had help
from an unexpected source.
The Aldermaston team struggled for a while
with the moulding of plutonium, how you get it into a stable state.
But then Penney told them the answer was
to alloy the plutonium with another metal.
This metal was gallium.
They were all convinced that Penney had got this information
because he was maintaining contacts with American scientists,
he was going out to dinner with them,
he was in correspondence with them.
They were convinced he got this under the table
from American friends.
A kind of spying. HE CHUCKLES
But in order to process enough uranium
to make the plutonium core of the bomb,
they had to build a massive reactor on the Cumbrian coast at Windscale.
It was going to be a very close-run thing,
even if everything worked perfectly.
And, of course, not everything did.
And so there had to be some pretty extraordinary actions taken.
Any problems were dealt with very expeditiously,
maybe in ways that one would find a bit odd today.
Vic Goodwin would experience first-hand
some of the unusual working practices
which built up during this period.
They were about to discharge some fuel from reactor one, I think,
and the fuel would fall out of the back of the reactor
into railway trucks.
But some of it ricocheted along the huge corridor
towards the bottom of that big chimney that you can see.
And the people had worked out the best thing to do
was to send a man in with a shovel.
And since I had just arrived and I was fit and young and a trainee,
I was clearly that man.
The fuel elements were intensely radioactive,
so my job was to get as many of these operations done
until I reached a set radiation value,
which is considered rather high nowadays.
But, then, it was approximately five old-fashioned chest X-rays
and one's minder made sure that one didn't receive more.
So, I think people of a nervous disposition
or who were not well-informed
would not be the right people to send in on that job.
Unconventional methods were also used
when it came to transporting the plutonium.
They had to take the plutonium core to Woolwich to be tested for flaws.
Now, that was done by placing them in canisters -
lead canisters - and putting them in the back of a Vauxhall car
and driving them around the outskirts of South London
to Woolwich. Unfortunately, the car broke down
and there is this moment when the car is stopped outside a pub,
somebody knocks on the door of the pub in the middle of the night
and gets the publican to phone somebody and a back-up is brought.
Now, that meant that, for some hours,
the core of the British bomb was sat in a broken-down Vauxhall
outside a pub somewhere south of London.
# Atomic baby
# I'm the atomic baby
# Better handle me with care. #
By 1951, Britain's atomic bomb was nearing completion.
And this is what it was all about.
At the heart of the top-secret atomic research establishment
at Aldermaston, Ken Johnston, for the first time,
introduces the bomb they created.
This is our first nuclear weapon that went into service.
Here is the physics package,
which detonates the central core of plutonium.
It's operated by a series of detonators,
attached, each one, to an explosive lens,
which focus the detonation wave onto the central plutonium core.
And the plutonium core is inserted, at the last practicable moment,
in the top of the device.
And here it is. This is a scale model.
And you insert it right into the core
and click it into place
and then your warhead is armed and ready to be used.
And now it had to be tested.
In February 1952, Operation Hurricane was launched.
The aircraft carrier HMS Campania escorted an old destroyer,
HMS Plym, on her last voyage.
On board the Plym was the atomic bomb,
which was to be exploded in her hold just off the Australian coast.
Ted Baker, then a 19-year-old new recruit,
was one of the photographers on the mission.
It was exciting cos it was so different
to what I'd done beforehand - you know,
attending weddings, christenings,
portrait photography and so forth.
So, totally different. Totally different.
The explosion was scheduled for October 3rd, 1952.
The Plym was abandoned with the atomic bomb on board.
Ted Baker was watching from HMS Campania, 15 miles away.
I was on deck at the time.
There was an air of quietness
and there was this feeling, wondering what's going to happen.
One or two of the sailors, you could see them sort of with
a strained look on their face, listening to the countdown.
Five, four, three, two, one, now.
EXPLOSION
And then, when the bomb went off, a flash of light appears.
I mean, we'd had our backs to it,
and then, when you could sort of turn round,
it didn't look like I thought it would look.
It developed into this zigzag as the wind took it.
In scientific terms, the explosion was a massive success
with a yield of 25 kilotonnes -
more powerful than the bomb dropped over Nagasaki.
The first few seconds of the explosion
were filmed on a specially built camera,
which could capture more frames per second
than any other camera in existence at the time.
This is the cine-camera. It ran at 150,000 frames a second.
It was designed specifically for the very early stages
of when the bomb went off.
Now, for the first time,
Aldermaston has released the images taken by the camera.
It's a bit sort of thin there,
but it is the very, very early stages
of the weapon going off.
These are taken every 8 millionths of a second
and they show the fireball developing.
And there's a great interest in the rate of growth of the fireball
cos it gives a good idea of what the overall yield is.
William Penney and his scientists
measured the size of the historic test,
but not all his instruments were hi-tech.
William Penney would use all sorts
of sophisticated methods to do it, but also anything that came to hand,
like bent jerry cans, and in this case,
Penney was able to deduce
exactly what pressure struck these paint tubes.
And since he knew the distance,
he could tell what the device had produced in the way of a yield.
And it was a very simple and cheap
and maybe rather British way of doing things.
Since this test and the others that followed,
thousands of veterans have claimed
they've suffered health problems as a result,
claims which have not been accepted by successive governments.
But the political significance of the test was clearer.
For Winston Churchill, who had just been re-elected as Prime Minister,
it marked Britain's entry into the nuclear club.
Once we had fired an atom bomb,
the feeling was that we were now in the same nuclear league
as America and Russia, and that, therefore,
it would be reasonable to seek a reopening of the exchanges
that we'd had with the Americans during the war.
But the feeling of triumph was short-lived.
EXPLOSION
Just three weeks later, the Americans exploded Ivy Mike.
This was an entirely new type of nuclear bomb,
400 times more powerful
than the atomic bomb the British had just tested.
It was the first hydrogen bomb.
So, the hopes that the British had had -
that by showing they could make an atomic bomb,
they would put themselves level with the Americans - were lost.
Suddenly, they were miles behind again.
As one congressman put it, when it was suggested
that they should resume contacts with the British, he said,
"Why would we trade a horse for a rabbit?"
And that horse was a bomb which had breached a new frontier
in nuclear physics.
It was so powerful because, instead of using fission -
the splitting of atoms -
it had succeeded in harnessing the power of nuclear fusion.
This required massive pressure and temperature
to fuse atoms together and create exponential amounts of energy.
A year later, the Soviet Union exploded Joe 4,
their own hydrogen bomb.
The Prime Minister Winston Churchill
responded by making the controversial decision
that Britain should build its own hydrogen bomb...
..for national prestige,
to impress the Americans and to deter Soviet aggression.
I would like to make quite sure
that the Russians would not press matters to a point
where we should all be led to a situation
which baffles the human imagination in its terror...
..but which I am quite sure...
..would leave us victorious,
but victorious on a heap of ruin. APPLAUSE
In 1954, he set a target -
Britain's H-bomb had to be ready within three years.
And what's more, if it was going to fulfil its political role,
the government wanted the scientists at Aldermaston
to ensure it had an explosive yield of one megaton -
two and a half times as powerful as the Soviet bomb.
At around this time,
the man they call the father of the British hydrogen bomb,
Bryan Taylor, arrived to start work at Aldermaston.
My first introduction to it was
I was shown this office in a wooden shed
which I shared with someone else.
But I met my friend and colleague Keith Roberts,
and just sort of said, "Well, what are you doing?"
And he said, "Well, the government's just announced
"that we're going to make a hydrogen bomb.
"We don't actually know how to do it.
"Have you got any ideas?" But once I'd got settled in,
it was really very stimulating and very exciting,
something, you know, at the forefront of theoretical physics,
which is my speciality.
And yet, unlike so much of theoretical physics,
it was something which might even have an influence
on what happened on earth.
The scientists faced two problems -
what material to use to fuel the fusion reaction
at the heart of the bomb...
..and second, how to trigger that reaction.
The British knew from the atmospheric readings
of the American H-bombs
that they'd used deuterium as a fusion fuel,
but the Aldermaston scientists thought they could do better.
Instead of using deuterium,
which is difficult to handle and store,
we decided to use lithium deuteride.
This both provides the deuterium which is needed...
..but also the lithium component is easier to ignite
than deuterium alone.
But it soon became clear that igniting a fusion reaction
in lithium deuteride required such high temperatures and pressure
that only an atomic explosion would start the process.
So, we end up with something like this.
There's an outer case...
..in which there is a primary - a fission weapon -
generally known as Tom...
..and a secondary - the thermonuclear material -
generally known as Dick.
And the object is to get the radiation
from the primary Tom to surround...
..Dick rather uniformly
so that it's compressed to a tight focus at the centre
where the temperature will rise
and the thermonuclear reaction will start.
But this design posed a huge problem.
Would the atomic bomb blow the whole device up
before the fusion process had even begun?
The question was is it possible
to get the radiation from the trigger, Tom,
to completely surround the secondary, Dick,
in a more or less uniform fashion
before the radiation or the mechanical pressure
has blown the whole thing apart?
And to do this, the idea was
we'd fill the space between Tom and Dick
with a very low density material,
through which the radiation would pass rather rapidly.
And to stop it all escaping and blowing everything apart,
one makes the case of material of high electron density
through which the radiation goes much more slowly.
And the key to everything is
are these two speeds sufficiently different
that it will do what one wants it to do?
Professor Taylor and his colleagues were not deterred
by their great scientific challenge.
Look, I was 27, and at that age, you can do anything.
And, remember, this was not so long after the war
when people much younger than me had done amazing things.
So, one thought that, you know,
"If the Americans have done it, surely we can do it."
But there were some challenging points, yes.
But there was another problem looming on the horizon -
Soviet and American nuclear bomb tests
were provoking a furious public reaction.
# Just a plain bomb is bad but that A-bomb is worse
# They done named that H-bomb well
# Thousand times stronger than that A-bomb is
# It's going to blow us all to kingdom come... #
The anti-bomb movement started to grow rapidly.
By the mid-'50s, there was worldwide public alarm
at the risk to humanity and to the planet
of these great explosions...
..that so much radioactive dust
was being pumped up into the upper atmosphere
that the whole planet was being poisoned,
and that led to suggestions there should be a moratorium,
there should be a halt, a ban,
on atmospheric testing or all testing, indeed.
EXPLOSION
Under huge pressure from around the world,
the two nuclear powers, America and the Soviet Union,
planned to declare a moratorium on atmospheric nuclear testing.
The British government feared it would be imposed
before their hydrogen bomb was tested.
The moratorium on testing
was to kick in in late 1958,
and so it was a race against time
to conduct those tests
and achieve the scientific success that we needed.
So, the government announced Operation Grapple.
The testing of Britain's H-bomb
would take place as soon as possible,
but first huge support and test sites had to be built
on the other side of the world.
The difficulty of achieving this massive task
was only too clear to the man who helped oversee the operation.
It was an enormous project.
They were asking us to build a major airbase
on a very large desert island in the middle of the Pacific,
and erect two camps, one as big as a small city.
And when we had done all that,
we then had to go and prepare Malden Island,
which was going to be the target.
But it was quite obvious that what we were being asked to do
by the War Office was not possible.
They had to give us more men.
So, we moved soldiers from Korea,
and it was very tough on some of them.
They didn't see their wives for about two years.
Throughout 1957,
the test ban moratorium talks gathered momentum.
For the scientists,
the pressure to get their one-megaton hydrogen bomb
ready for testing was intense.
For the first time, Britain's bomb-maker-in-chief
shows us the hydrogen bomb
which was to become the British nuclear deterrent.
Here we have the first hydrogen bomb
that went into service with the RAF for the United Kingdom.
It's codenamed Red Snow,
and it's contained in this aerodynamic dropping case,
which, however, departs from being truly aerodynamic
when you come to the front end.
Where we have chopped off the end, it's completely flat,
and the point of that is to slow the fall of the bomb,
so that the bomber, which has released it,
can turn away and make its escape,
because otherwise it could be seriously damaged
by the flash and the blast from the hydrogen bomb.
In November 1957, Operation Grapple X was ready to go.
The bomb was flown out to the Pacific in a Valiant bomber.
On board were the co-pilot, Alan Pringle,
and his navigator, Derek Tuthill.
The enormous bomb bay had been especially adapted
to carry the H-bomb.
This is the start of the bomb bay,
and it extends approximately 35-40 feet
with the bomb sitting inside,
filling at least three quarters of the space, I would say.
But they knew virtually nothing
about the bomb which they were carrying.
If you were a crew member...
..you were taught just to fly the aircraft. Kept in the dark.
I mean, we weren't allowed to see the weapon in the bomb bay.
They had a screen rolled up
round that part of the aircraft... Yes. ..so we couldn't even peep.
We knew remarkably little about it.
Finally, on the 8th of November 1957,
the go-ahead for the test was given.
There was a delay of about an hour once we were airborne
because a ship was spotted in the critical part of the sea
where the bomb was about to burst,
and we had to wait while it sailed out of the area of immediate danger.
On Malden Island,
various observation huts were set up.
They've never been filmed before. Ted Baker was in one of them.
It was referred to as a cube because they are square on there,
which housed a lot of the recording equipment.
There was possibly about 20 people in there.
It was quite tense, actually, with everything sort of building up
to the point, you know, where the weapon is released,
you hear the countdown and everything on there.
You like to feel that
you're in control of your emotions and everything,
but you're just wondering what's going to happen. And you waited.
OVER RADIO: 'Steady. Steady. Steady, steady, steady. Now.'
At 17.47 Greenwich Mean Time,
Alan Pringle and the crew dropped the bomb
and made the sharp turn to escape its blast.
EXPLOSION
The thing I remember most of all is the flash.
We had very dark welder's glass over the windows,
and the light from that explosion was so bright,
it didn't damp out the flash at all.
We suddenly saw the outside as clear as daylight.
It was far brighter than I've ever seen a light in my life, I think.
When the weapon went off, you'd get some blast,
you'd hear it sort of thump on there.
When you went outside to view,
then you saw the mushroom cloud forming into like a tube.
It just appeared like a ballerina's skirt,
and it looked a lot bigger than anything I'd seen previously.
The H-bomb had a yield of 1.8 megatons.
For the scientists, it was a triumph,
although you wouldn't have known it from their reaction.
There wasn't any shouting and yelling and hullabaloo at all.
It was just scientific people looking at one another and saying,
"It looks as though we've got something good here."
I don't remember that I jumped up and down
and punched the air or anything like that.
I mean, it was just the feeling that, scientifically,
we'd demonstrated that this was the way to go.
I'm sorry to admit that I was rather more concerned
about the scientific aspects
than the political or the patriotic aspects.
The scientists had defied the odds
and realised the politicians' dreams.
I think, having independently developed a hydrogen bomb,
and pretty soon put one into service,
it achieved exactly what the Foreign Office wanted,
which was a place at the top table.
Shortly afterwards, the American and British governments
signed an agreement to share atomic information.
The British had only just got there in time.
Three months later, a nuclear test ban was announced,
ending atmospheric bomb tests.
Sir William Penney, the man behind the British bomb programme,
summed up the scientists' justification for their work.
SIR WILLIAM PENNEY: The energy and enthusiasm
which have gone into the making of this new weapon stemmed essentially
from the sober hope that it would bring us nearer the day
when world war is universally seen to be unthinkable.
Did Bryan Taylor feel any qualms
about creating such a terrifying weapon?
Well, I'm afraid not, no. I viewed it as a scientific problem,
and the main aim was that we should not all fall over
with egg on our faces.
My government had announced that it was going to have a hydrogen bomb,
and so it better have one, else it would look very foolish.