NS Military Worldbuilding Thread No. 12

[Austrasien]

Recently, someone told me that nuclear war during the cold war could not destroy human beings, or even the hegemony of the United States and the Soviet Union.The air blast radius of a 300000 ton nuclear bomb is five kilometers. If you want to destroy the solid ground fortifications, the killing radius is only 0.9 km.That would take 200 warheads to destroy Moscow.If the city is not in the plain area, the effect will be worse. In addition, most of the nuclear warheads in the nuclear arsenals are tactical ones, and the first wave is aimed at enemy military facilities, and the radiation of nuclear weapons will disappear in a few days.Therefore, MAD will not destroy human beings, but only 1 / 4-1 / 3 of each other's population and 1 / 2-2 / 3 of each other's industrial production capacity.So,Nuclear bombs can't destroy human beings, and can't make small countries like NK absolutely safe?

It would probably permanently reduce the USSR/USA to regional powers of a substantially lower rank, much like the collapse of the USSR did to Russia.

[New Solaurora]

The other two remain unaffected because they are the equivalent of solid steel blocks which requires a very, very great deal of force to affect in anyway.
This is all assuming the conventional explosives even exploded from impacting the ground... which it didn't do every time a nuclear bomb goes through a Broken Arrow.

As to setting off two more bombs, that's pretty much in the impossible realm.

Maybe all three have radio command fuses and the crash causes the detonation command to be broadcast..

Again that also flies in the face of all common sense in regards to handling atomic weapons.

I should clarify that this takes place during a battle and that each side has a atomic weapon. At what stage were safety features installed onto the explosive mechanism because maybe one of them could be still in the testing phase (don't worry about how it got there)? And if the one that was in the plane crash was damaged could it be triggered by the explosion of another weapon?

[Gallia-]

In later versions of the Fat Man you would install the main fuse just prior to dropping the bomb. Which means someone (usually the bombardier) would crawl into the bomb bay and arm the weapons, like in Dr. Strangelove.

In WW2 the Fat Man was armed with a big ass lanyard when it was dropped from the bomb bay, and it had to go through several checks of altitude (barometer, radar altimeter, and accelerometer I think? I guess the lanyard did the latter one) before it would fuse properly. The bomb was loaded "armed" with some plastic plugs installed in it which determined the pre-set fuse height in defined increments. Supposedly the color of the plugs determined if the bomb was a inert or live one (green for inert, red for live bomb) but I imagine it was more just the colors they had more likely. So the bomb already came pre-fused more or less.

Anyway if they all didn't agree (for example if the bomb was just dropped on the flight line) or something I guess it would just not work. But it's still full of literal tons of high explosive and will kill you if it explodes.

It's basically impossible to make an atom bomb go off spontaneously with anything resembling real life safety features, even the relatively lax ones of the WW2. That said a Little Boy (gun type) is more dangerous than a Fat Man (implosion) since a gun-type can theoretically be detonated spontaneously if you make it ignite the kicker without wrecking the rest of the bomb I guess. Implosion bombs require more precise detonation sequences and thus are inherently safer. At least as safe as something like 500-1000 lbs of TNT blowing up in your face can be.

Gun-types being simpler applies more to the ever hypothetical suicide truck nuke though than accidental detonations.

[Triplebaconation]

I'm pretty sure early nuclear weapons weren't as safe as commonly believed.

If a plane carrying an armed early bomb broke up there's a good chance it would go off - and they were armed well before reaching the target area.

The Goldsboro bomb would have certainly "initiated" (to use a term that makes it look like I know what I'm talking about) if it had been 1945 vintage.

[Gallia-]

rip

[Triplebaconation]

Once the plugs were changed the safety was basically the pin on a hand grenade.

50s and 60s electromechanical safety systems were really pretty bad, and the only thing preventing serious accidents was a combination of manual procedures and luck.

[The Manticoran Empire]

I'm pretty sure early nuclear weapons weren't as safe as commonly believed.

If a plane carrying an armed early bomb broke up there's a good chance it would go off - and they were armed well before reaching the target area.

The Goldsboro bomb would have certainly "initiated" (to use a term that makes it look like I know what I'm talking about) if it had been 1945 vintage.

It actually did. 3 of the 4 mechanisms required to fully arm the weapon activated.

[New Solaurora]

So is the scenario possible or not? Doesn't have to be super likely just possible with some terrible luck. (1945 atomic tech just a reminder)

[Manokan Republic]

Last try at the tank I have mentioned earlier:

(Image)

Seems good to me man, it will never be exactly perfect, tanks in real life usually aren't eitheir xD

[Manokan Republic]

Recently, someone told me that nuclear war during the cold war could not destroy human beings, or even the hegemony of the United States and the Soviet Union.The air blast radius of a 300000 ton nuclear bomb is five kilometers. If you want to destroy the solid ground fortifications, the killing radius is only 0.9 km.That would take 200 warheads to destroy Moscow.If the city is not in the plain area, the effect will be worse. In addition, most of the nuclear warheads in the nuclear arsenals are tactical ones, and the first wave is aimed at enemy military facilities, and the radiation of nuclear weapons will disappear in a few days.Therefore, MAD will not destroy human beings, but only 1 / 4-1 / 3 of each other's population and 1 / 2-2 / 3 of each other's industrial production capacity.So,Nuclear bombs can't destroy human beings, and can't make small countries like NK absolutely safe?

It depends on the nuclear bomb's level of power, and how it's used, but the main problem will be radioactive fall-out killing people over many years rather than the physical destruction of buildings and people from the blast itself. If were to have everyone in an underground bunker for a few months and go under before the nuclear blast, you may not even have 10% of the population die, which stands to reason this may be a good idea for everyone to have (on top of an air filter, water filter and food storage systems and so on as well). That also being said, electromagnetic radiation wiping out the electric infrastructure would be another key problem. Nothing could remain running without electricity in the modern day, or very little, and what little can still needs electricity along the way to make it useful. A single nuke at 300 miles up could wipe out the electric infrastructure for most the U.S., for example. As we don't have enough transformers to replace this or a way to communicate in the event of a disaster without electronics to repair the power lines, we'd be screwed. In essence, even if you could repair the destroyed power lines, we don't have enough extra power lines laying around to do so or a way to organize people in the event it may happen, and if by some miracle we did, another EMP could be launched some time later, and several right in a row.

Building powerlines at least 5 feet underground could stop a lot of this, as it would block out most of the radiation, and they'd be less likely to be knocked over during a storm or hurricane so, it seems like a good idea.

[Triplebaconation]

oh no

So is the scenario possible or not? Doesn't have to be super likely just possible with some terrible luck. (1945 atomic tech just a reminder)

Yeah, sympathetic detonation is possible. How possible depends on factors impossible to predict so go crazy.

[New Vihenia]

So yeah...on subject of nuclear powered armored vehicle/Tanks etc. The main hurdles would be the weight of shielding required to protect the crew and its surroundings from the radiation from the reactor

Is that true ?

[Gallia-]

oh no

So is the scenario possible or not? Doesn't have to be super likely just possible with some terrible luck. (1945 atomic tech just a reminder)

Yeah, sympathetic detonation is possible. How possible depends on factors impossible to predict so go crazy.

blimp delivered little boys

this is what the united stellar states of the milky way (USSotMW) fears

[Manokan Republic]

So yeah...on subject of nuclear powered armored vehicle/Tanks etc. The main hurdles would be the weight of shielding required to protect the crew and its surroundings from the radiation from the reactor

Is that true ?

Yes For the most part, as is heat management and finding a reliable way to generate electricity, although a sterling engine is not a bad idea for this. In addition, the armor can serve as a way of blocking out the radiation, as metal and depleted uranium are also pretty good at blocking out radiation, as is a faraday cage, so depending on the design, it can be far lighter weight than you might expect with an existing armored vehicle. Early designs for nuclear powered vehicles often were designed to be flying and used extremely hot liquids to mechanically spin the turbines as they needed to move at really high speeds with a lot of energy, which lead to a lot of problems and required a lot out of the design. Although in theory more efficient to convert the heat directly to mechanical energy, in practice it rarely is, which is why hybrid electrics tend to have better fuel efficiency than standard combustion engines, and far simpler designs. The complication of needing to boil salt mixtures at high levels and then run this to a wheel or turbine to spin and radiation proof the whole thing is just not worth it in comparison to converting it to electricity and having a more efficient electric drivetrain. You also can operate at lower temperatures using just the heat difference between the environment to generate the electricity. With a design like this you could likely get away with just radiation proofing the hot cube of uranium, and then this heat would be used to run the sterling engine.

[Arkandros]

Yes For the most part, as is heat management and finding a reliable way to generate electricity, although a sterling engine is not a bad idea for this. In addition, the armor can serve as a way of blocking out the radiation, as metal and depleted uranium are also pretty good at blocking out radiation, as is a faraday cage, so depending on the design, it can be far lighter weight than you might expect with an existing armored vehicle.

First off, faraday cages are not shielding. blocking EM transmissions and stopping gamma/beta/neutron radiation is entirely different, and a faraday cage operates on an entirely different principle than nuclear shielding. Secondly, your bigger concern is going to be the crews who spend days or weeks a matter of feet from the reactor, which puts your shielding internal to the armored vehicle, thus making it deadweight. I won't get into actual shielding calculations because talks of energy windows and borate doping will probably go over your head, but expect at least a solid 2-3 inches of lead between crews and your reactor.

Early designs for nuclear powered vehicles often were designed to be flying and used extremely hot liquids to mechanically spin the turbines as they needed to move at really high speeds with a lot of energy, which lead to a lot of problems and required a lot out of the design.

The working fluid for airborne nuclear reactors has always been air. Their primary coolant has only *sometimes* been air. Yes, that air has been extremely hot (to maximize usable work), and yes, sometimes air is referred to as a fluid, but your later comments lead me to believe you did not understand this. This is *crucial* to understanding the limitations of mobile reactors, because their efficiency will always be limited by their heat transfer to their heat sink (ie, air temperature and density).

Although in theory more efficient to convert the heat directly to mechanical energy, in practice it rarely is, which is why hybrid electrics tend to have better fuel efficiency than standard combustion engines, and far simpler designs.

[insert power supply here]-electric plants are more efficient (amazingly, you aren't wrong on this) because they let the speed changing happen electronically as opposed to mechanically, allowing the mechanical drive to run continuously at its ideal rotational speed and avoid throttling losses. The gain in efficiency from the continued run at ideal speed is what gives you the ability to tolerate the conversion losses. The electric system itself really has no efficiency gain, it's just enabling a more efficient operational load for the mechanical system. Your comment about far simpler though is straight up wrong.

The complication of needing to boil salt mixtures at high levels and then run this to a wheel or turbine to spin(discussed earlier) and radiation proof the whole thing is just not worth it in comparison to converting it to electricity and having a more efficient electric drivetrain. You also can operate at lower temperatures using just the heat difference between the environment to generate the electricity.

No matter what you do, you have to shield your reactor (and preferably your coolant loops in a closed loop system), and you can't just appear electricity from nowhere. Your reactor has to heat a working fluid to generate electricity, and either that fluid or some intermediary will have to touch the core to be heated, which means it can contain fission or fuel particulates and should be shielded. The only way to not do this is to use a RTG, which would be absolutely hilariously moronic for dozens of reasons, least of which is its abysmal efficiency.
As for lower temperatures, as discussed previously, your efficiency will be entirely based on your temperature difference. A lower temperature differential means lower efficiency, and thus less power.

With a design like this you could likely get away with just radiation proofing the hot cube of uranium

You have literally just described a primary shield arrangement. Every extant nuclear system has a primary shield, though largely for reflection and not purely shielding. This will rarely be sufficient for personnel safety while operational.

Honestly, I can't even be assed to get into your gross conceptual misunderstanding of MSRs, so I recommend as a bare minimum reading the wikipedia entry on nuclear reactors before you start posting about them again.

[Miku the Based]

First off, faraday cages are not shielding. blocking EM transmissions and stopping gamma/beta/neutron radiation is entirely different, and a faraday cage operates on an entirely different principle than nuclear shielding. Secondly, your bigger concern is going to be the crews who spend days or weeks a matter of feet from the reactor, which puts your shielding internal to the armored vehicle, thus making it deadweight.

, and yes, sometimes air is referred to as a fluid,

As for lower temperatures, as discussed previously, your efficiency will be entirely based on your temperature difference. A lower temperature differential means lower efficiency, and thus less power.

Kind of confused with Faraday cages not blocking EM light, particularly gamma radiation in this context, isn't Faraday cages sussposed to block all forms of electromagnetism? Beta and neutron radiation are particle radiation, right? I don't really know what neutrinos are, they seem to pass through everything. You are right, It needs lead shielding as a default.
About being a fluid, I remember that when learning aerodynamics in physic classes, it borrows a lot from fluid mechanics. But could air be compressed to the point where it lowers it's condensation point and actually becomes a liquid at a certain temperature? Would that help with heat distribution? I'm not sure if we are referring to a liquid that's normally air at room temperature and pressure or just referring to air as a fluid as a concept.
About temperature, what do you mean lower temperature differential? I'm confused, does it mean the difference of temperature outside the closed system then inside the closed system? Le so how does that relate to efficency and what relationship does it have to effeciency?

Honestly, I can't even be assed to get into your gross conceptual misunderstanding of MSRs, so I recommend as a bare minimum reading the wikipedia entry on nuclear reactors before you start posting about them again.

Pretty harsh.

[Gallia-]

speaking of molten salt lmao

[New Vihenia]

I'm thinking about Nuclear gas turbine for the nuclear tank tho. a closed cycle with say maybe Helium coolant. Tho inefficient, it's the lightest option.

[Triplebaconation]

Kind of confused with Faraday cages not blocking EM light, particularly gamma radiation in this context, isn't Faraday cages sussposed to block all forms of electromagnetism?

A Faraday cage only blocks EM radiation with a wavelength greater than its mesh size. The wavelength of gamma and x-ray radiation is generally smaller than the gaps between atoms in metal.

It's probably worth noting that all the atomic tanks of the 50s were just rough sketches by tank engineers with little knowledge of the practical issues of nuclear power. Some seem to have paid no attention to shielding at all.

[The Corparation]

About being a fluid, I remember that when learning aerodynamics in physic classes, it borrows a lot from fluid mechanics. But could air be compressed to the point where it lowers it's condensation point and actually becomes a liquid at a certain temperature? Would that help with heat distribution? I'm not sure if we are referring to a liquid that's normally air at room temperature and pressure or just referring to air as a fluid as a concept.

Air is a gas and gases are fluids. You can compress air into the liquid phase, but that's not what Ark was talking about nor is it really applicable to this situation. Ark is referring to air as a fluid because, as he said, it's the working fluid, which is to say it it is the fluid that is doing the mechanical work in the system.

Manokan seems to have the idea that in the aircraft reactor designs it is the reactor's coolant boiling which causes the "turbine to spin". This is not the case, for these designs the primary coolant merely transfers heat from the reactor core into the engine where it's used to heat up air. The expansion of that air as it heats is what is actually drives the turbine. The liquid salt and metal coolants intended to be used in nuclear aircraft reactor designs were typically expected to remain liquid during operation.

[Miku the Based]

[.
The expansion of that air as it heats is what is actually drives the turbine. .

Isn't that a given in any reactor, coal and nuclear power plants uses water to turn into water vapor to do the work of pushing the mechanical and electrical turbine. So in these aircraft reactors they use air instead. Never heard of these air reactors, is it a open system that requires a air intake?

[The Corparation]

[.
The expansion of that air as it heats is what is actually drives the turbine. .

Isn't that a given in any reactor, coal and nuclear power plants uses water to turn into water vapor to do the work of pushing the mechanical and electrical turbine. So in these aircraft reactors they use air instead. Never heard of these air reactors, is it a open system that requires a air intake?

For most aircraft reactors it works basically the same as a conventional a jet engine. The primary difference is that instead of burning jet fuel to heat the air, you have a heat exchanger that heats the air.

Simplified diagram of a nuclear turbojet


Note that this while this diagram depicts a turbojet you could just as easily have a turbofan, turboshaft or ramjet. (Although for a ramjet you would likely forgo the coolant loop in favor of routing the air direct through the reactor instead.)

[Barfleur]

I don't know how popular Popular Mechanics is on this thread, but here's an interesting article I read this morning.

Is anything going to come of this? Should anything come of this? Or is it just a pipe dream/money hole/another 4.5 generation fighter that will never actually fight?

[Austria-Bohemia-Hungary]

I don't know how popular Popular Mechanics is on this thread, but url=https://www.popularmechanics.com/military/aviation/a35865601/f-36-kingsnake-air-force-next-fighter-jet-concept/]here's and interesting article I read this morning.[/url]

Is anything going to come of this? Should anything come of this? Or is it just a pipe dream/money hole/another 4.5 generation fighter that will never actually fight?

hello F-16XL

[Triplebaconation]

I don't know how popular Popular Mechanics is on this thread, but url=https://www.popularmechanics.com/military/aviation/a35865601/f-36-kingsnake-air-force-next-fighter-jet-concept/]here's and interesting article I read this morning.[/url]

Is anything going to come of this? Should anything come of this? Or is it just a pipe dream/money hole/another 4.5 generation fighter that will never actually fight?

Nothing's going to come of a notional illustration on Hush-Kit.

If the US actually builds a more affordable supplement to the F-35 it almost certainly won't look like that. It'll either be a new block of actual F-16s or something like the F-35's various conceptual predecessors.