rickair7777

True, one time use and unmanned would eliminate some shielding requirements.

Not true, the core (pit) of a fission bomb is not as heavy or complicated as a reactor core.

A reactor core needs a specific physical geometry based on physics and the desired use, which requires structure strong enough to withstand the heat, working fluid flow, and flight forces (neutron flux wouldn't hurt the structure if it's only used once).

Then you need a control system, control rods and operating mechanism. This could be a bit lighter by simply jettisioning part of it to activate the engine.

Then you need moderating material, water typically serves that function, but that would be far to heavy since you'd need a large pressurized cooling system and large circulating water reserve to keep it from flash boiling. So an appropriate solid, carbon or certain metals.

You would need some shielding but if you locate ALL of the electronics forward of the engine a simple layered lead/hydrocarbon fuselage plug would probably do the trick.

If you got REALLY creative, you could actually reduce the weight of the warhead a tiny bit by taking advantage of the engine neutron flux as a booster for the bomb.

That's for sure, nothing safe whatsoever about this concept.

I think they'll build it, but probably not deploy it in large numbers, ie first strike numbers. They know that would generate a response from the US, and they don't what that would be or if they could afford to counter it. The US looks pretty passive until you threaten or attack the homeland, nothing new there, pretty consistent historical data on that and everybody knows it by now. Even Saddam knew that, he just got left holding AQ's bag.

They might also have the motive of discouraging us (some future government) from expanding our BM defense to a large enough scale to threaten the utility of their current BM deterrent force. That would not be unreasonable, and might be accomplished with a modest number of non-ballistic weapons.

Winston

https://en.m.wikipedia.org/wiki/Project_Pluto

Also:

https://www.google.com/amp/s/jalopni...1435286216/amp

Excargodog

A lot of the work on this has already been done:

https://www.sciencedirect.com/scienc...38573315001540

All the theoretical work for an extremely high temperature gas cooled reactor has been done, the rest is just sort of engineering. Ambient air may be somewhat less efficient than using liquid H2, but an air breathing missile has sort of an infinite supply of it and at Mach 5 or 6 will get to wherever it’s going in at most four or five hours. As far as being able to throttle the power, it really only needs one power setting since it can travel hypersonic all the way to the target.

As the reference states, all that is really required is the political will to overcome the public reluctance to have nuclear powered rockets flying overhead. The technology is pretty well worked out.

Well, maybe not yet worked out enough for the Russians, but I doubt that either public opinion or the occasional loss of a handful of scientists will stop them if they have really decided to do it.

tomgoodman

Here’s a good BBC article on the “Tsar Bomba”. Since Khruschchev wanted the test in time for a Soviet Party Congress and couldn’t resist leaking, our secret squirrels at Wright-Patterson were able to position a special airplane very close.

BBC - Future - The monster atomic bomb that was too big to use

rickair7777

I think it needs to throttle actually, a hypersonic vehicle cannot be stealthy due to the immense thermal signature. I suspect you would want such a weapon to be able to cruise at a cool subsonic speed to get in close before sprinting to the target. Easy to throttle a reactor core (long as you don't need it to go to zero after a high power run!), the harder part would be designing the engine to deal with fluid dynamics at different flight speeds.


I think the public will accept nuclear spacecraft engines for deep space missions (we already use RTGs on some long-range spacecraft), you just need to mitigate the risk during launch to orbit. Probably have to package the thing to survive launch vehicle failure or unplanned re-entry (could ditch the heavy packaging prior to departing earth orbit). The engine would only actually be operated when leaving earth orbit and enroute, not in the atmosphere. If politically necessary, you could depart orbit on a conventional engine and the use the nuke in deep space.

I actually think this sort of nuclear engine offers the best path manned to mars. There are many technical and medical challenges to long deep space missions... reliability of flight hardware, temporary and permanent physiological degradation, cosmic/solar radiation exposure (at some point it would be essentially a guaranteed premature death sentence for the crew). A nuclear engine could cut mission transit time dramatically.

I also think instead of hemming and hawing about the affects of zero-G, they just need to accept the fact that the ship will need to be large and heavy enough to do centrifugal spin for gravity. Yes it will cost more but it could also be re-used many times (deep space or as a space station) if modular so that you can replace upgrade/components while retaining the main structure.

I have ethical reservations about sending folks on a mission that's going to destroy their health and probably kill them after they get home.


Nope, rooskies don't care. The US could build similar systems if necessary, since it would be a deterrent/doomsday weapon, the risk associated with the engine would be largely irrelevant. Although we might have to plan launch from ships/subs/aircraft, to avoid flying an operating nuclear engine over our people.

Elevation

Here's the Convair program that we had in the 60s. There's some interesting notes about their proposal for the development of the power unit.

The Russians are doing the same thing.

https://www.youtube.com/watch?v=4VcXqtl3FAI

Elevation

https://nationalinterest.org/feature...aircraft-13352

Here's a quick link to some other nuclear propulsion plans we had. They ranged from nuclear-electric bombers, direct air contact with fissile materials in ram and scramjets and elaborate systems of liquid salts to transfer heat to air without exposing radioactive materials. Nuclear turbojets were proposed as well.

The only systems we have announced flying was a nuclear-electric B-36.

We tested a high specific impulse nuclear rocket and deemed it flightworthy with the NERVA motor.

Nuclear space propulsion got pretty weird too, like with Dyson's Orion propulsion system.

Elevation

The Outer Space Treaty is holding back a lot of things right now. Ending o leaving the OST will lead to weaponized space stations again (Polyus, etc.), but would speed up commercial opportunities in space.

redeyed

I've gotta put in a pitch for the 1964 movie, "Dr. Strangelove" (from Stanley Kubrick, producer of "2001, A Space Odyssey . It's an insanely-funny look at the flawed human condition in the context of an accidental nuclear strike against the Russians. It's black and white, so some of you won't be interested; but it was accurate enough that the film crew got in a lot of trouble from the DOD for the depictions of the B-52 cockpit and armament systems, as well as the nuclear protocols of the time. Some great one-liners if you like to poke fun at pilots and other flawed individuals.

JamesNoBrakes

One of the best movies of all time.