Tube Alloys and a British nuclear programme

Gunnarnz

The Manhattan project produced US nuclear weapons, and the German version was fundamentally flawed and probably couldn't have produced one no matter how long it went on for. Both of those get debated a fair bit around here anyway, so let's talk about something else...

With a POD as close to 1939 as possible, could the British have produced nuclear weapons in time for WW2 without American assistance? How long would it have taken them? And what would be required for them to a) decide to make the effort and b) succeed in delivering one?
Bonus points if they manage to equal the timing of the Manhattan project IOTL.
 

Color-Copycat

I think the US got the majority of physicists fleeing from mainland Europe, so maybe that could be a good starting point for the British to be more open to taking in that critical human resource.
 

Abgrund

Color-Copycat said:
I think the US got the majority of physicists fleeing from mainland Europe, so maybe that could be a good starting point for the British to be more open to taking in that critical human resource.
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Endorsed. This is the key. Given the scope of the Empire, there could hardly be a question of obtaining uranium. Most of the rest is just some serious brainwork by a few dozen people.

Little Boy involved a huge amount of difficult industrial work to separate isotopes of uranium. With a hardcore 1939 start and a flash of insight or two, I could see Fat Man laughing in Berlin by 1943, made in U.K.
 

sloreck

While personnel is a problem, the biggest one is money and resources. The resources needed for the Manhattan Project were huge - building materials (just for scientist/technician housing), concrete, etc etc. The Oak Ridge works used a huge percentage of US silver reserves for making electromagnets copper being needed for shell casings etc. Huge amounts of electric power were needed, one reason the projects went where they did is the TVA and the Columbia River dams/electric generation provided plenty of power. The UK did not, as I understand, have those sort of reserve of electric power that could diverted from immediate needs like building ships, tanks, a/c, etc.

As crappy as German (and especially Luftwaffe targeting) intel was, anything as big as a UK Manhattan Project might have been noticed, and bombed - even relatively ineffective bombing would gum up the works and a lucky hit really mess things up. Early on had the Germans known where to bomb such a project they probably could have hit it. The advantage the US had was complete safety, and an ability to use empty places to provide security.
 

Stephen

Banned
sloreck said:
As crappy as German (and especially Luftwaffe targeting) intel was, anything as big as a UK Manhattan Project might have been noticed, and bombed - even relatively ineffective bombing would gum up the works and a lucky hit really mess things up. Early on had the Germans known where to bomb such a project they probably could have hit it. The advantage the US had was complete safety, and an ability to use empty places to provide security.
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What if they did it somewhere else in the Empire like Australia?
 

vanguard

OTL British, Commonwealth and refugees based in the UK, were absolutely key to the allied atomic bomb programme. For example, the entire French group Frédéric Joliot-Curie, Hans von Halban, Lew Kowarski, and Francis Perrin that showed that fission gives off addition neutron were in Cambridge by 1940. Similarly the Germans , Rudolf Peierls and Otto Frisch who first calculated the required mass of fissile material were in England. Thats before were include the Cavendish Laboratory team who proposed that a slow neutron reactor would breed Plutonium.

In terms of practical work, ICI received a contract for 3kg of Uranium Hexafluoride as early as 1940 by gaseous diffusion centrifuge. These were installed at the giant Billingham chemical works in the north east of England. Had this programme expanded, and tube alloys not moved lock stock and barrel to the US, then the UK might have managed one or two Mk1 style bombs by 1945.

Although the combined programme was bigger than the UK could possibly afford, it was also bigger than required. The UK bet correctly on gaseous diffusion, so a simpler programme based on Uranium would have worked. Billingham was big enough that it might not have drawn suspicion, but a move to Chalk River in Canada may have been more sensible in any case.

POD is that the same pressures that led to OTL McMahon Act prevent allied co-operation leading to rival prgrammes, even in wartime. The UK dosn't even need to develop the B29 since the Lancaster is big enough to carry the weapon (biggest single air dropped bomb of the war was the 10,000 kg Grand Slam). Can they get it to Berlin by, say, January 1945. Possibly.

Just my thoughts gents
 
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vanguard

sloreck said:
While personnel is a problem, the biggest one is money and resources. The resources needed for the Manhattan Project were huge - building materials (just for scientist/technician housing), concrete, etc etc. The Oak Ridge works used a huge percentage of US silver reserves for making electromagnets copper being needed for shell casings etc. Huge amounts of electric power were needed, one reason the projects went where they did is the TVA and the Columbia River dams/electric generation provided plenty of power. The UK did not, as I understand, have those sort of reserve of electric power that could diverted from immediate needs like building ships, tanks, a/c, etc.

As crappy as German (and especially Luftwaffe targeting) intel was, anything as big as a UK Manhattan Project might have been noticed, and bombed - even relatively ineffective bombing would gum up the works and a lucky hit really mess things up. Early on had the Germans known where to bomb such a project they probably could have hit it. The advantage the US had was complete safety, and an ability to use empty places to provide security.
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Our potential UK programme does not need to be as big as Manhattan. Just develop the simpler Mk1 Uranium bomb, not the Mk3 in parallel. Just extracting U235 by gaseous diffusion not centrifuge or (especially) Calutrons means a much smaller British Oak Ridge at Billingham without the electromagnets and huge power consumption. No need for a British Hanford either if we don't need Plutonium.

The UK could have done it, since it effectively got lucky in picking the right technology, whereas the Americans took no chances and developed everything.
 
Grey Wolf

Grey Wolf

Donor
vanguard said:
OTL British, Commonwealth and refugees based in the UK, were absolutely key to the allied atomic bomb programme. For example, the entire French group Frédéric Joliot-Curie, Hans von Halban, Lew Kowarski, and Francis Perrin that showed that fission gives off addition neutron were in Cambridge by 1940. Similarly the Germans , Rudolf Peierls and Otto Frisch who first calculated the required mass of fissile material were in England. Thats before were include the Cavendish Laboratory team who proposed that a slow neutron reactor would breed Plutonium.

In terms of practical work, ICI received a contract for 3kg of Uranium Hexafluoride as early as 1940 by gaseous diffusion centrifuge. These were installed at the giant Billingham chemical works in the north east of England. Had this programme expanded, and tube alloys not moved lock stock and barrel to the US, then the UK might have managed one or two Mk1 style bombs by 1945.

Although the combined programme was bigger than the UK could possibly afford, it was also bigger than required. The UK bet correctly on gaseous diffusion, so a simpler programme based on Uranium would have worked. Billingham was big enough that it might not have drawn suspicion, but a move to Chalk River in Canada may have been more sensible in any case.

POD is that the same pressures that led to OTL McMahon Act prevent allied co-operation leading to rival prgrammes, even in wartime. The UK dosn't even need to develop the B29 since the Lancaster is big enough to carry the weapon (biggest single air dropped bomb of the war was the 10,000 kg Grand Slam). Can they get it to Berlin by, say, January 1945. Possibly.

Just my thoughts gents
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Very interesting, thank you! I've got nothing to add but have often wondered about this, especially spurred on by Len Deighton's "SS GB" whose plot revolves around the issue, and Fritsch in particular

Best Regards
Grey Wolf
 

Astrodragon

One other possibility is that the British look at the two options - U235 and Plutonium and do better costings; this leads them to going for the Plutonium bomb (even though its more risky) because they decide they just cant afford the U-235 route.
The Plutonium bomb is far more affordable (over 3/4 of the cost of Manhattan was for the Uranium bomb), and easily within the capacity of the Empire - it would be developed in Canada, who were heaviliy involved in the OTL British work, a safe country, easy access to resources, and US tech available to buy over the border.

The Lancaster can deliver a bomb in Europe - if you need to drop one on Japan, the B-29 is probably the only option, though you arent talking about more than a handful of hand-build convertions, after all...
 

Dupplin Muir

It's often claimed that the Lancaster's ceiling was too low to safely drop an atomic bomb, but this was due to a conscious decision not to fit high-altitude Merlins: when they did (with the Lancaster VI) it could cruise happily at 28,000 feet, which seems reasonably safe, especially if the aircraft goes into a shallow dive after dropping the bomb.
 

Astrodragon

Dupplin Muir said:
It's often claimed that the Lancaster's ceiling was too low to safely drop an atomic bomb, but this was due to a conscious decision not to fit high-altitude Merlins: when they did (with the Lancaster VI) it could cruise happily at 28,000 feet, which seems reasonably safe, especially if the aircraft goes into a shallow dive after dropping the bomb.
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they would also have lightened it to the extreme to improve performance, and probably hand-tweaked the engines as well
 

vanguard

The "toss-lob" method of bomb release was designed to allow safe delivery of atomic weapons by low flying aircraft. Not the easiest maneuver in a Lancaster of course......

I agree that the Plutonium route would have been cheaper. Chalk River in Canada was the first reactor outside of the US in any case, so just fast forward this at little and you could beat the Chicago pile. This means less difficulty with Uranium enrichment and a lower overall cost, but in 1941 is a bigger gamble.

Either way, the UK could have been first without any changes to out TL other than the willingness of the allies to co-operate.

UK05
 

jkay

If Bomb development had been separated, it probably would've stretched too long to have had any effect on the war, and Japan would've had to've been invaded. Bomb development was really, really, really hard, so a joint effort was needed for it be done on time.

Getting enough pure bomb-grade materials is still hard enough to be what keeps nuclear proliferation slow.

Sorry.... Now, there's an alternate interesting challenge, which is, thread, how can you make unified Bomb development happen on Commonwealth turf?
 

FlyingDutchman

Dupplin Muir said:
It's often claimed that the Lancaster's ceiling was too low to safely drop an atomic bomb, but this was due to a conscious decision not to fit high-altitude Merlins: when they did (with the Lancaster VI) it could cruise happily at 28,000 feet, which seems reasonably safe, especially if the aircraft goes into a shallow dive after dropping the bomb.
Click to expand...

Weight and size of a nuke however isn't going to any issue with the Lancaster.

Problematic isn't just altitude (maybe the Vickers high altitude bomber design would be better then the Lancaster), but speed as well.
The B-29 was only barely capable of dropping a nuke and surviving it while being 100+ km/h faster then the Lancaster.

You could OTOH deploy a nuke by parachute, but that opens a whole different can of worms as the nuke will get vulnerable to AA(A) that way.
Considering the amount and quality of AA(A) any German target is going to have, that's a no-no IMHO.

However, if you solve this problem you would save IIRC 4 billion USD in not having to design and build a next generation bomber compared to the Lancaster in addition to the cost of the whole Tube Alloys program...
 
Grey Wolf

Grey Wolf

Donor
FlyingDutchman said:
Weight and size of a nuke however isn't going to any issue with the Lancaster.

Problematic isn't just altitude (maybe the Vickers high altitude bomber design would be better then the Lancaster), but speed as well.
The B-29 was only barely capable of dropping a nuke and surviving it while being 100+ km/h faster then the Lancaster.

You could OTOH deploy a nuke by parachute, but that opens a whole different can of worms as the nuke will get vulnerable to AA(A) that way.
Considering the amount and quality of AA(A) any German target is going to have, that's a no-no IMHO.

However, if you solve this problem you would save IIRC 4 billion USD in not having to design and build a next generation bomber compared to the Lancaster in addition to the cost of the whole Tube Alloys program...
Click to expand...

Or you don't work it out, calculate it wrong, still deliver the bomb OK but wipe out the bomber - and worry about the problem for the second bomb, where your bomber crews are going to be a bit more insistent on certain safeties!

Best Regards
Grey Wolf
 

rip89

FlyingDutchman said:
Weight and size of a nuke however isn't going to any issue with the Lancaster.

Problematic isn't just altitude (maybe the Vickers high altitude bomber design would be better then the Lancaster), but speed as well.
The B-29 was only barely capable of dropping a nuke and surviving it while being 100+ km/h faster then the Lancaster.

You could OTOH deploy a nuke by parachute, but that opens a whole different can of worms as the nuke will get vulnerable to AA(A) that way.
Considering the amount and quality of AA(A) any German target is going to have, that's a no-no IMHO.

However, if you solve this problem you would save IIRC 4 billion USD in not having to design and build a next generation bomber compared to the Lancaster in addition to the cost of the whole Tube Alloys program...
Click to expand...
Maybe the RAF gets a dozen or so B29s through Lend Lease? Or fits underwing jets to lancs similar to what the USAF did with B36s to give greater boost speed?
 
Shimbo

Shimbo

The British/Canadians could definitely build a nuclear weapon if they gave the project enough priority. In fact in hindsight Britain's best strategy in 1939 would be to stay on the defensive and put as much money as necessary into the nuclear weapon and the Victory Bomber. Of course at the time it didn't seem that way, it was just one speculative wonder weapon project amongst many.

The idea that the British didn't have the scientists is not accurate. I've posted many times before the key breakthrough in realising the atomic bomb was a practical proposition was actually British. In 1940, the British (in fact Otto Frisch and Rudolf Peierls working for the British) correctly appreciated that the amount of Uranium 235 required was far less than previously thought (pounds rather than tons).

In late 1940, the British MAUD committee produced a report outlining the feasibility of the bomb, which was sent to the Americans but ignored until Marcus Oliphant flew to the USA in 1941, to impress on the US scientists the feasibility and urgency of manufacturing the bomb.

The obvious PoD is that the MAUD report somehow gets massive traction in the British government/military is correctly seen as the war winner that it is, and regarded as so vital that it's kept from the USA. Although given how the British gave every military and scientific secret they had to the USA in OTL, that's highly unlikely.
 
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