Radiation and the atomic bombing of Japan.

[Didymus]

You mean reliable? Or what, exactly?

I'm sure Catsmate1 meant "safe," albeit with the user, not the target, in mind. To make a more powerful un-boosted fission bomb means assembling several critical masses of uranium or plutonium and keeping them from exploding before the bomb reaches its target. One mechanism was to fill the hollow space in the core of the bomb with something that would either absorb neutrons or prevent compression. One British bomb had to have ball-bearings poured out of it after loading it onto the bomber. A US bomb used an aluminum chain to absorb neutrons. The chain was pulled out of the core as the bomb dropped.
One's mind boggles.

 

[Gawdzilla Sama]

I'm sure Catsmate1 meant "safe," albeit with the user, not the target, in mind. To make a more powerful un-boosted fission bomb means assembling several critical masses of uranium or plutonium and keeping them from exploding before the bomb reaches its target. One mechanism was to fill the hollow space in the core of the bomb with something that would either absorb neutrons or prevent compression. One British bomb had to have ball-bearings poured out of it after loading it onto the bomber. A US bomb used an aluminum chain to absorb neutrons. The chain was pulled out of the core as the bomb dropped.
One's mind boggles.

Obligatory "Dr. Strangelove" pix goes here.

 

[lobosrul]

As ably proven by the Australian Bren Gunners in New Guinea and the British Bren Gunners in Burma.

The Bren was certainly not a sub-machine gun. It was a (damn good) light machine gun, or squad automatic weapon, firing a full powered rifle round. Actually, the Japanese copied it:

http://en.wikipedia.org/wiki/Type_96_Light_Machine_Gun
http://en.wikipedia.org/wiki/Type_99_Light_Machine_Gun

 

[MG1962]

Ah ◊◊◊◊. I've a bad habit of missing stuff like that recently.

Yes, Japan was one of the few combatants, and the only major one, to fail to produce a decent SMG in large numbers. Particularly bad idea given their utility in jungle warfare and the generally poor Japanese light machine guns.

Yes the first time I saw those stick loaded magazines I thought they were a joke

 

[Gawdzilla Sama]

Yes the first time I saw those stick loaded magazines I thought they were a joke

They were.

 

[catsmate]

You mean reliable? Or what, exactly?

Both. Inducing fission is tricky, you need to convert a mass of material from a safe to an unsafe form very quickly. The efficiency of the design, how big an explosion results from a certain mass depends on a number of factors, one of them being the design of the implosion system. In fact the MK3, MK4 and MK5 bombs used the same 'pit' (fissionable core) but improvements in the implosion lens design improved yield from 20kt to 120kt over the various models. Later designs were 'boosted' with tritium injected before implosion to produce extra neutrons or used Oralloy for the pit, an alloy of plutonium and highly-enriched uranium.

Of course if you use a larger fissionable mass you can get a bigger bang, but at the price of a bomb that's more prone to safety problems; the classic example of thing being the UK 'Green Grass' or Knobkerry interim weapon (one of the most powerful non-fusion bombs ever deployed). Green Grass used a hollow cast core with 70kg of Oralloy (more than ten critical masses) kept rigid by tens of thousands of ball bearings that were drained before the carrier aircraft took off.
The RAF described the design as "inherently unsafe" and believed it impossible for an aircraft to land while carrying the armed bomb, or to ditch it safety without a "near certainty" of a nuclear explosion.
In addition to the huge mass of fissionable material the design did not follow US practice in using insensitive high explosive or a fire-resistant pit design, further compromising safety.

As ably proven by the Australian Bren Gunners in New Guinea and the British Bren Gunners in Burma.

True, they used the excellent Bren quite well as a heavy assault rifle, as well as a LMG.
And of course the Australians had the excellent Owen as well.

 

[catsmate]

I'm sure Catsmate1 meant "safe," albeit with the user, not the target, in mind. To make a more powerful un-boosted fission bomb means assembling several critical masses of uranium or plutonium and keeping them from exploding before the bomb reaches its target. One mechanism was to fill the hollow space in the core of the bomb with something that would either absorb neutrons or prevent compression. One British bomb had to have ball-bearings poured out of it after loading it onto the bomber. A US bomb used an aluminum chain to absorb neutrons. The chain was pulled out of the core as the bomb dropped.
One's mind boggles.

I missed this, so most of my previous post is redundant. The US design you refer to was the infamous MK18, another very high yield (~500kt) fission bomb. These were scrapped rapidly when true fusion bombs became available.

Yes the first time I saw those stick loaded magazines I thought they were a joke

The Italians had a similar design (the Breda 30) to to the Japanese Type 11. Both were poor to awful weapons though the Breda was worse, requiring oiling of cartridges to extract properly.

 

[dudalb]

Never ceases to amaze...

Best Understatement Ever.

 

[dudalb]

The Bren was certainly not a sub-machine gun. It was a (damn good) light machine gun, or squad automatic weapon, firing a full powered rifle round. Actually, the Japanese copied it:

http://en.wikipedia.org/wiki/Type_96_Light_Machine_Gun
http://en.wikipedia.org/wiki/Type_99_Light_Machine_Gun[/QUOTE)


Not accurate. The Japanese types resembeled the Bren but was a different design. The Japanese LMG type 96 and 99 were nowhere near as reliable or accuarte as the Bren.

 

[Noztradamus]

Both. Inducing fission is tricky, you need to convert a mass of material from a safe to an unsafe form very quickly. The efficiency of the design, how big an explosion results from a certain mass depends on a number of factors, one of them being the design of the implosion system. In fact the MK3, MK4 and MK5 bombs used the same 'pit' (fissionable core) but improvements in the implosion lens design improved yield from 20kt to 120kt over the various models. Later designs were 'boosted' with tritium injected before implosion to produce extra neutrons or used Oralloy for the pit, an alloy of plutonium and highly-enriched uranium.

"Oralloy" (Oak Ridge Alloy) was the wartime code name for plain weapons grade Uranium

"Tube Alloy" (originally developed the British Tube Alloy Project) was Plutonum 239.

(The Brits have a knack for innocuous-sounding euphemism eg "Target Marker B" = Tactical nuclear bomb).

 

[Gawdzilla Sama]

"Oralloy" (Oak Ridge Alloy) was the wartime code name for plain weapons grade Uranium

"Tube Alloy" (originally developed the British Tube Alloy Project) was Plutonum 239.

(The Brits have a knack for innocuous-sounding euphemism eg "Target Marker B" = Tactical nuclear bomb).

I've never heard "Tube Alloy" used that way.

 

[TubbaBlubba]

This thread fuelled my interest somewhat in Hirohito's degree of involvement, responsiblity and motivations during World War II and Sino-Japan II.

It seems pretty obvious that he was directly involved and that the expansionist prospects of Imperial Japan were of great importance to him (and that his big beef with Sino-Japan II was that it was drawn out), but I was a bit surprised at how much he appeared to be your run-of-the-mill scheming dynastic politician. It seems like his main interest, above all else, was invested in maintaining the relevancy, continuity and power of the Imperial House, and making sure that whatever happened, blame would not fall upon the Imperial Family.

 

[MG1962]

This thread fuelled my interest somewhat in Hirohito's degree of involvement, responsiblity and motivations during World War II and Sino-Japan II.

It seems pretty obvious that he was directly involved and that the expansionist prospects of Imperial Japan were of great importance to him (and that his big beef with Sino-Japan II was that it was drawn out), but I was a bit surprised at how much he appeared to be your run-of-the-mill scheming dynastic politician. It seems like his main interest, above all else, was invested in maintaining the relevancy, continuity and power of the Imperial House, and making sure that whatever happened, blame would not fall upon the Imperial Family.

This book is an absolute must read if you want to understand the origins of WW2 from a Japanese perspective

http://www.amazon.com/Japan-1941-Countdown-Eri-Hotta/dp/0307594017

 

[Corsair 115]

To cap it off nicely, read Eri Hotta's Japan: 1941. I really want a Japan: 1945 from this author.

Hold placed in the library system here for this title. Thanks for the recommendation!

 

[bigred]

I wonder how Americans would have reacted to news after the war that Truman had a weapon that could have won the war, but let a couple of hundred thousand servicemen be killed or injured instead

Then they would have pissed and moaned about that instead. It's a "60s thing"

Anyway, excellent thread all, props. Will have to check out some of the referenced books.

 

[Gawdzilla Sama]

This thread fuelled my interest somewhat in Hirohito's degree of involvement, responsiblity and motivations during World War II and Sino-Japan II.

It seems pretty obvious that he was directly involved and that the expansionist prospects of Imperial Japan were of great importance to him (and that his big beef with Sino-Japan II was that it was drawn out), but I was a bit surprised at how much he appeared to be your run-of-the-mill scheming dynastic politician. It seems like his main interest, above all else, was invested in maintaining the relevancy, continuity and power of the Imperial House, and making sure that whatever happened, blame would not fall upon the Imperial Family.

Are you familiar with the "Liaison Conference" system? If so I won't go on.

 

[TubbaBlubba]

Are you familiar with the "Liaison Conference" system? If so I won't go on.

Nope.

 

[Gawdzilla Sama]

Nope.

Okay. The government ministers, plus other parties as needed, meet in what was called "Liaison Conferences" to decide on major items of Imperial policy. You can call this a "Cabinet" if you wish, but it was a bit different in important aspects.

The most important members were the Prime Minister, the Foreign Minister, the Army and Navy Ministers, and the Chiefs of Staff of the two military branches. The last two were automatically assigned to the government when they were appointed to their position. The Army and Navy ministers were required by a fairly recent modification of the Constitution to be active duty military men. This meant the military could bring down a government or stop a new one from being formed simply by reassigning a Minister or refusing to assign him to the job. This meant that any government existed by the sufferance of the Army and Navy.

THe purpose of the Liaison Conferences was to create a "smooth" statement of policy to be present to Hirohito in the "Imperial Conference" that followed the Liaison conferences and gave the divine stamp to the policy. It was considered very bad form to go into an Imperial Conference because this would upset the Emperor, or worse, give him a chance to say something that would change policy.

The most important instance of an Imperial Conference that didn't have a unified front was the one where the question of surrender was being debated after Nagasaki. This illustrated the caution the Liaison Conferences exercised in only giving the Emperor one option to chose from. Hirohito used his chance to express his own opinion about the war, and this as much as anything, caused Gen. Anami, the head Army man, to come over to the surrender faction and lead to the cessation of hostilities.

 

[TubbaBlubba]

Okay. The government ministers, plus other parties as needed, meet in what was called "Liaison Conferences" to decide on major items of Imperial policy. You can call this a "Cabinet" if you wish, but it was a bit different in important aspects.

The most important members were the Prime Minister, the Foreign Minister, the Army and Navy Ministers, and the Chiefs of Staff of the two military branches. The last two were automatically assigned to the government when they were appointed to their position. The Army and Navy ministers were required by a fairly recent modification of the Constitution to be active duty military men. This meant the military could bring down a government or stop a new one from being formed simply by reassigning a Minister or refusing to assign him to the job. This meant that any government existed by the sufferance of the Army and Navy.

THe purpose of the Liaison Conferences was to create a "smooth" statement of policy to be present to Hirohito in the "Imperial Conference" that followed the Liaison conferences and gave the divine stamp to the policy. It was considered very bad form to go into an Imperial Conference because this would upset the Emperor, or worse, give him a chance to say something that would change policy.

The most important instance of an Imperial Conference that didn't have a unified front was the one where the question of surrender was being debated after Nagasaki. This illustrated the caution the Liaison Conferences exercised in only giving the Emperor one option to chose from. Hirohito used his chance to express his own opinion about the war, and this as much as anything, caused Gen. Anami, the head Army man, to come over to the surrender faction and lead to the cessation of hostilities.

Ah, that clears some things up. Thanks.

Considering what happened even after the surrender, I can't imagine the emperor would actually realistically have had the ability to single-handedly to end the hostilities at any other point. Seems more likely he would be placed under house arrest and business would go on as usual.

 

[Gawdzilla Sama]

Ah, that clears some things up. Thanks.

Considering what happened even after the surrender, I can't imagine the emperor would actually realistically have had the ability to single-handedly to end the hostilities at any other point. Seems more likely he would be placed under house arrest and business would go on as usual.

There was an attempt to intercept his speech, recorded on a vinyl LP record, and take the Emperor into "protective custody" the night before the announcement was to be aired. Things could have gone differently if they'd been lucky enough.