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To be fair as aircraft get more and more complex there's a lot stages of the flight where computers are controlling most of the controls anyway.

That said I agree with wars heading more and more (esp for western nations) toward fighting guerrillas and insurgents more so than big battle-lines, the value of larger ordinance delivery systems like plans reduces. You don't really want or need to carpet bomb a whole city, you just want a handful of drones to hit specific structures.

 Grey Templar wrote:
It probably won't ever get to the point we have a fully autonomous AI aircraft. We're still a long way from programming the judgement necessary to decide if a strike is appropriate.

Realistically, it will be a unmanned aircraft that is remotely controlled by a human on the ground, but is capable of flying and landing/taking off on its own so you only need a human for actual combat. And maybe you can have some AI assistance in fighting a target that has already been approved.

Of course this all assumes that aircraft remain practical weapons in the future. Realistically, aircraft and missiles will become obsolete within the next few decades as countermeasures for them become more powerful.

There's always a place for the latest incarnation of weapons technology, its just bringing them to bear becomes more situational and requires more prep work.

Yeah, truly weaponised lasers are not far off now, some hand held lasers can already put a hole through metal within seconds with an appropriate focussing lens/crystal, the weaponised versions that will be mounted on the ground, ships and planes themselves will be able to shoot down or at least damage to the point of being operationally ineffective are on their way.

As soon as the power sources are in place, they will ruin any planes day.

On a point, apparently some rather huge strides on nuclear fusion are inbound, and it will genuinely be a viable technology within the next few decades, and some reactors will be small/compact. The viability increase is in part due to lasers, especially for the compact versions as the technology is starting to catch up enough that a reactor design based on lasers super heating hydrogen is soon to be viable. At which point, the perfect power source for said weaponised lasers exists.

Sweet. I’m going to invest in Vault Tec, Rad-Away, Stimpacks, power armour, a tough-ass dog, a plasma rifle, assault rifle, and an electric chainsaw.

Come at me, 2020!

 greatbigtree wrote:
Sweet. I’m going to invest in Vault Tec, Rad-Away, Stimpacks, power armour, a tough-ass dog, a plasma rifle, assault rifle, and an electric chainsaw.

Come at me, 2020!

I should really start saving bottle caps

As mentioned with the nuclear reactors, if we can get fusion reactors to a reasonable size, and it is increasingly looking like we could get them similar sized to a car engine, we will see power armor, among other amazing things. Cars and other vehicles that have a self-contained nuclear reactor much like a modern nuclear sub(IE: the reactor has enough fuel to outlast the lifespan of the vehicle) that never needs refueling. This will be what gets us off of fossil fuels, not solar, wind, etc...

As I've said before. Once we get lasers that can trivially shoot down missiles and aircraft, or even with just a respectable success rate, what probably happens is warfare reverts back to armored ground combat. Indirect artillery, heavily armored tanks, and power armor infantry along with regular infantry. This also would end the reign of MAD doctrine and make nuclear weapons obsolete as a deterrence. An ICBM is useless if it has a massive chance of getting shot down as soon as it clears the horizon.

These AA lasers and their power supplies will also become dirt cheap quite quickly. Sure, the first few years of their existence it would be only used by 1-2 countries, but eventually it would spread out and even the people in Buttcrack'istan are going to have a couple.

 Nevelon wrote:

 greatbigtree wrote:
Sweet. I’m going to invest in Vault Tec, Rad-Away, Stimpacks, power armour, a tough-ass dog, a plasma rifle, assault rifle, and an electric chainsaw.

Come at me, 2020!

I should really start saving bottle caps

Ring pulls too. Often forgotten, some sub-sections may choose to use those, if caps are harder to come by.

 Grey Templar wrote:
As mentioned with the nuclear reactors, if we can get fusion reactors to a reasonable size, and it is increasingly looking like we could get them similar sized to a car engine, we will see power armor, among other amazing things. Cars and other vehicles that have a self-contained nuclear reactor much like a modern nuclear sub(IE: the reactor has enough fuel to outlast the lifespan of the vehicle) that never needs refueling. This will be what gets us off of fossil fuels, not solar, wind, etc...

As I've said before. Once we get lasers that can trivially shoot down missiles and aircraft, or even with just a respectable success rate, what probably happens is warfare reverts back to armored ground combat. Indirect artillery, heavily armored tanks, and power armor infantry along with regular infantry. This also would end the reign of MAD doctrine and make nuclear weapons obsolete as a deterrence. An ICBM is useless if it has a massive chance of getting shot down as soon as it clears the horizon.

These AA lasers and their power supplies will also become dirt cheap quite quickly. Sure, the first few years of their existence it would be only used by 1-2 countries, but eventually it would spread out and even the people in Buttcrack'istan are going to have a couple.

What if someone comes up with a practical countermeasure to lasers? It may be that aircraft and missiles start being coated in heat-resistant plating like the space shuttles, for example, that don't allow a laser to burn through before the missile impacts the target.

Everyone said the exact same thing about missile technology back in the 50's, but missiles still haven't obsoleted aircraft, and have arguably made aircraft more relevant as missile delivery systems. There is a very real chance that lasers could obsolete aerial units, but there is an equally real chance that anti-laser tech evolves to keep them in service.

I'd bet that the US military is working on countermeasures alongside their lasers.

 Haighus wrote:

 Grey Templar wrote:
As mentioned with the nuclear reactors, if we can get fusion reactors to a reasonable size, and it is increasingly looking like we could get them similar sized to a car engine, we will see power armor, among other amazing things. Cars and other vehicles that have a self-contained nuclear reactor much like a modern nuclear sub(IE: the reactor has enough fuel to outlast the lifespan of the vehicle) that never needs refueling. This will be what gets us off of fossil fuels, not solar, wind, etc...

As I've said before. Once we get lasers that can trivially shoot down missiles and aircraft, or even with just a respectable success rate, what probably happens is warfare reverts back to armored ground combat. Indirect artillery, heavily armored tanks, and power armor infantry along with regular infantry. This also would end the reign of MAD doctrine and make nuclear weapons obsolete as a deterrence. An ICBM is useless if it has a massive chance of getting shot down as soon as it clears the horizon.

These AA lasers and their power supplies will also become dirt cheap quite quickly. Sure, the first few years of their existence it would be only used by 1-2 countries, but eventually it would spread out and even the people in Buttcrack'istan are going to have a couple.

What if someone comes up with a practical countermeasure to lasers? It may be that aircraft and missiles start being coated in heat-resistant plating like the space shuttles, for example, that don't allow a laser to burn through before the missile impacts the target.

Everyone said the exact same thing about missile technology back in the 50's, but missiles still haven't obsoleted aircraft, and have arguably made aircraft more relevant as missile delivery systems. There is a very real chance that lasers could obsolete aerial units, but there is an equally real chance that anti-laser tech evolves to keep them in service.

I'd bet that the US military is working on countermeasures alongside their lasers.

Firstly, such coating has weight, meaning the jets will have to be larger and/reduce payload and most likely will not be as fast and/or manoeuvrable. Secondly, they won't be able to be stealth then, at which point, you keep the missiles around as well.

Anyway, the trick with lasers is speed, they can be fired and reaching the target at literally the speed of light, that armour has to hold out for a long time then as the laser will be kept firing continuously at the target.

Lastly, I doubt they'll be able to heat proof most of the camera and sensors that need to be relatively external on the air frame, and that is specifically what they want to target with lasers. Combat ineffective is just as good as taking the enemy down in terms of dettering/stopping/defence against an attack, it's only in the long term you want to destroy to cost your enemy an asset.

Yup. But you don't just have to target cameras and sensors. Simply warping the wings can be a death sentence for modern fighters. The F35 basically can't take any damage whatsoever without becoming unflyable. A laser would find it easy to cause some slight warpage.

Any possible countermeasure to a laser given our current understanding of physics would involve a prohibitive amount of weight being added. Which would turn the plane or missile into a slow cumbersome thing that would have little combat use.

Once lasers like this become common, the only aircraft that will see combat use will be unarmed scout drones that rely on being undetected, but once they are detected will promptly get shot down. Transport aircraft might still exist, but they'll be too risky to use in an actual combat zone. You'll fly in, land in a safe spot, and then walk/drive to the combat area.

This will have a ripple effect in that it will kill aircraft carriers and we will return to having ships that focus on using direct/indirect fire with conventional artillery+railguns. All ships will probably have drone hangers to launch scout drones, but nothing with direct combat capabilities. The drones will have to be disposable and cheap as well. Submarines will lose their missile silos and go back to being torpedo caddies, though they could also mount railguns and use those to mount hit and run attacks too. Maybe even very large railguns that could launch small nuclear warheads as a replacement for ICBMs.

Kind of funny, the Hammer's Slammers series by David Drake is based on this kind of thought process.

Aircrafts as combat arms are obsolete (they are still good transports in a non-battle situations) because the weapons of the MBT's and armoured cars can shoot, computer network assisted, any aircraft as it clears the horizont. The weapons, in automated air-defence mode, are used to shoot down artillery shells as they clear the horizont.

The tanks have reverted to be the main combat arms again, Powered by fusion bottles, they have the armour, speed and weaponry to fight against any foe.

The artillery is still the queen of the battlefield, but only when the opposing air defences are compromised (as the computer assisted power weapons can kill anything in line of sight, including the artillery shells). The rocket assisted artillery shells have enormous range and come with variety of munitions; anti-infantry, bunker busters, tank busters, gas and even nuclear.

There is a kind of gizmo existing in the books that stops nuclear weapons from detonating (This is just to keep everybody from using nuclear weapons in the books. That would make boring stories…)

Infantry also uses hand held power weapons (altough less powerful versions from the MBT's) and single shot rockets (called "buzzbombs") that can take out the tanks and armoured cars if used close enough. So the infantrys main use is to keep the enemy infantry away from the tanks.

Most vehicles use ground effect for mobility (because they are powered by fusion bottles).

The terran forces (not seen in the books, but referred to a few times) actually have anti-grav mobility and their infantry are equipped with power armour. But the mercenary forces depicted in the books do not have Access to that kind of equipment.

Very nice book series written in around 1979, but depicting the future of warfare.

I know it's 'prohibited' under the outer space treaty, but seriously... Railguns are going to be space based at some point, and I believe they will be more combat efficient in space also, as current and even probably future tech can't make rails that can last more than a few shots (5 max) due to the intense heat generated and they need to be replaced.

Such heat generation possibly won't be as much of a huge issue in space (this is me putting 2 and 2 together by the way, not an engineer) as space will be the ultimate heat sink.

As soon as they are up there, war with anything large is over, done, unless you're going to throw so much resources at a target to make the rail guns run out of ammo. I'm fully aware space mounted rail guns will be most likely WMD's BTW, so it's not quite as done and dusted as I say, you aren't going to use them on targets in built up areas but you get what I mean.

There may be some effect of lasers to be honest though that I don't fully understand that can ruin an orbital based rail guns day (either orbital based itself, or ground based), getting way beyond my applicable knowledge now to be honest, more than happy to be educated on the matter though if any of you guys have understanding of it.

endlesswaltz123 wrote:
I know it's 'prohibited' under the outer space treaty, but seriously... Railguns are going to be space based at some point, and I believe they will be more combat efficient in space also, as current and even probably future tech can't make rails that can last more than a few shots (5 max) due to the intense heat generated and they need to be replaced.

Such heat generation possibly won't be as much of a huge issue in space (this is me putting 2 and 2 together by the way, not an engineer) as space will be the ultimate heat sink.

This actually backwards. Space is terrible for getting rid of excess heat as the only method of losing heat in space is via radiation as there is no medium for a hot object to interact with and so you cannot use convection.

endlesswaltz123 wrote:

 Haighus wrote:

 Grey Templar wrote:
As mentioned with the nuclear reactors, if we can get fusion reactors to a reasonable size, and it is increasingly looking like we could get them similar sized to a car engine, we will see power armor, among other amazing things. Cars and other vehicles that have a self-contained nuclear reactor much like a modern nuclear sub(IE: the reactor has enough fuel to outlast the lifespan of the vehicle) that never needs refueling. This will be what gets us off of fossil fuels, not solar, wind, etc...

As I've said before. Once we get lasers that can trivially shoot down missiles and aircraft, or even with just a respectable success rate, what probably happens is warfare reverts back to armored ground combat. Indirect artillery, heavily armored tanks, and power armor infantry along with regular infantry. This also would end the reign of MAD doctrine and make nuclear weapons obsolete as a deterrence. An ICBM is useless if it has a massive chance of getting shot down as soon as it clears the horizon.

These AA lasers and their power supplies will also become dirt cheap quite quickly. Sure, the first few years of their existence it would be only used by 1-2 countries, but eventually it would spread out and even the people in Buttcrack'istan are going to have a couple.

What if someone comes up with a practical countermeasure to lasers? It may be that aircraft and missiles start being coated in heat-resistant plating like the space shuttles, for example, that don't allow a laser to burn through before the missile impacts the target.

Everyone said the exact same thing about missile technology back in the 50's, but missiles still haven't obsoleted aircraft, and have arguably made aircraft more relevant as missile delivery systems. There is a very real chance that lasers could obsolete aerial units, but there is an equally real chance that anti-laser tech evolves to keep them in service.

I'd bet that the US military is working on countermeasures alongside their lasers.

Firstly, such coating has weight, meaning the jets will have to be larger and/reduce payload and most likely will not be as fast and/or manoeuvrable. Secondly, they won't be able to be stealth then, at which point, you keep the missiles around as well.

Anyway, the trick with lasers is speed, they can be fired and reaching the target at literally the speed of light, that armour has to hold out for a long time then as the laser will be kept firing continuously at the target.

Lastly, I doubt they'll be able to heat proof most of the camera and sensors that need to be relatively external on the air frame, and that is specifically what they want to target with lasers. Combat ineffective is just as good as taking the enemy down in terms of dettering/stopping/defence against an attack, it's only in the long term you want to destroy to cost your enemy an asset.

Mirrors are pretty good at avoiding damage by lasers. The good quality ones anyway. While a black (at the wavelength of interest) surface might absorb a high percentage of the incident light, make it shiny chrome and you might only absorb a few percent. Of course, it doesn't really need to be chrome. The only practical directed energy lasers so far are all at about the same wavelength, so you only need a reflective coating that operates at that wavelength to give yourself significant extra survivability. It's just a coating, a few microns thick so that shouldn't add much weight.

Even better would be mirror shielding that could be aimed back at the laser. Most high-gain laser systems are pretty sensitive to feedback.

Maybe putting your plane into a roll as soon as it is targeted with a laser would help you spread the remaining heat out. Of course, that's probably not a comfortable way to fly for long periods, and probably messes up you getting to where you wanted to be :-)

I imagine planes could carry some sort of smoke screen which would pump out laser resistant smoke at the nose so it streams back over the plane.

Hexaprisms reflect a light beam back down the opposite path it arrived at. Maybe planes will be covered with hexaprisms.

I'm just spitballing here.

I've never been hugely convinced by the idea of using lasers to shoot down aircraft and missiles etc. It seems too simple to reflect beams.

Also, they're spectacularly non-eyesafe. Fire your laser at a target, then blind people within line of sight of that target when lots of stray reflections fire off in all directions? It would be tough to justify that collateral damage.

On the other hand, I hope that the people paying millions into laser development programmes know plenty that I don't and have thought this stuff through :-)

 A Town Called Malus wrote:

endlesswaltz123 wrote:
Such heat generation possibly won't be as much of a huge issue in space (this is me putting 2 and 2 together by the way, not an engineer) as space will be the ultimate heat sink.

This actually backwards. Space is terrible for getting rid of excess heat as the only method of losing heat in space is via radiation as there is no medium for a hot object to interact with and so you cannot use convection.

Really? I also would have thought the opposite... space is just above absolute zero, so even just with radiation I would have thought it'd be really effective... will have to look into it more, as now I'm super curious

 RiTides wrote:

 A Town Called Malus wrote:

endlesswaltz123 wrote:
Such heat generation possibly won't be as much of a huge issue in space (this is me putting 2 and 2 together by the way, not an engineer) as space will be the ultimate heat sink.

This actually backwards. Space is terrible for getting rid of excess heat as the only method of losing heat in space is via radiation as there is no medium for a hot object to interact with and so you cannot use convection.

Really? I also would have thought the opposite... space is just above absolute zero, so even just with radiation I would have thought it'd be really effective... will have to look into it more, as now I'm super curious

Space isn't cold. It also isn't hot. It's not anything, simply because it's completely empty. There's no stuff to be warm or cold. It's the same reason that drinks in a vacuum bottle stay scalding hot for hours: There's nowhere for the heat to go except via radiation, which is an extremely inefficient way to lose heat. So any heat you generate will stay there, and compound extremely rapidly.

 Grey Templar wrote:
Yup. But you don't just have to target cameras and sensors. Simply warping the wings can be a death sentence for modern fighters. The F35 basically can't take any damage whatsoever without becoming unflyable. A laser would find it easy to cause some slight warpage.

Any possible countermeasure to a laser given our current understanding of physics would involve a prohibitive amount of weight being added. Which would turn the plane or missile into a slow cumbersome thing that would have little combat use.

Once lasers like this become common, the only aircraft that will see combat use will be unarmed scout drones that rely on being undetected, but once they are detected will promptly get shot down. Transport aircraft might still exist, but they'll be too risky to use in an actual combat zone. You'll fly in, land in a safe spot, and then walk/drive to the combat area.

This will have a ripple effect in that it will kill aircraft carriers and we will return to having ships that focus on using direct/indirect fire with conventional artillery+railguns. All ships will probably have drone hangers to launch scout drones, but nothing with direct combat capabilities. The drones will have to be disposable and cheap as well. Submarines will lose their missile silos and go back to being torpedo caddies, though they could also mount railguns and use those to mount hit and run attacks too. Maybe even very large railguns that could launch small nuclear warheads as a replacement for ICBMs.

Eh, planes and missiles already have to tolerate a huge thermal range just due to the friction generated at high speeds. Extra thermal protection will undoubtedly add weight over no additional thermal protection, but a variety of light weight thermal protection systems have been developed already for other aerospace applications. For example, the SR-71 Blackbird was designed to tolerate over 300 degrees C on the leading edges, and the space shuttles designed to tolerate nearly 1700 degrees C on the leading edges. The latter used a material less dense than aluminium, a material notably developed for ICBM reentry, so we know it is practical on missiles.

So yes, effective laser point defense will require trade offs in performance of aircraft and missiles to add laser countermeasures, but existing materials can already dramatically increase thermal protection using low-density materials. The lasers will have to deliver very large amounts of energy in very short amounts of time to sufficiently damage missiles before they will hit the target regardless. With our current technology, this appears to be a more difficult technical challenge than increasing thermal resistance.

Also, as mentioned earlier, it is not really relevant to strike aircraft, as they can easily switch to fighting from behind the horizon with stand-off missiles. Missiles are the real focus, as they have to be able to survive the point defense.

Older equipment would be thoroughly obsoleted though.


Automatically Appended Next Post:

 Laughing Man wrote:

 RiTides wrote:

 A Town Called Malus wrote:

endlesswaltz123 wrote:
Such heat generation possibly won't be as much of a huge issue in space (this is me putting 2 and 2 together by the way, not an engineer) as space will be the ultimate heat sink.

This actually backwards. Space is terrible for getting rid of excess heat as the only method of losing heat in space is via radiation as there is no medium for a hot object to interact with and so you cannot use convection.

Really? I also would have thought the opposite... space is just above absolute zero, so even just with radiation I would have thought it'd be really effective... will have to look into it more, as now I'm super curious

Space isn't cold. It also isn't hot. It's not anything, simply because it's completely empty. There's no stuff to be warm or cold. It's the same reason that drinks in a vacuum bottle stay scalding hot for hours: There's nowhere for the heat to go except via radiation, which is an extremely inefficient way to lose heat. So any heat you generate will stay there, and compound extremely rapidly.

Technically, space is approximately 2.7 degrees Kelvin, because there is a measurable background radiation that provides energy. Supposedly the remnants of the Big Bang.

 Laughing Man wrote:

 RiTides wrote:

 A Town Called Malus wrote:

endlesswaltz123 wrote:
Such heat generation possibly won't be as much of a huge issue in space (this is me putting 2 and 2 together by the way, not an engineer) as space will be the ultimate heat sink.

This actually backwards. Space is terrible for getting rid of excess heat as the only method of losing heat in space is via radiation as there is no medium for a hot object to interact with and so you cannot use convection.

Really? I also would have thought the opposite... space is just above absolute zero, so even just with radiation I would have thought it'd be really effective... will have to look into it more, as now I'm super curious

Space isn't cold. It also isn't hot. It's not anything, simply because it's completely empty. There's no stuff to be warm or cold. It's the same reason that drinks in a vacuum bottle stay scalding hot for hours: There's nowhere for the heat to go except via radiation, which is an extremely inefficient way to lose heat. So any heat you generate will stay there, and compound extremely rapidly.

When ATCM mentioned convection I knew it sort of made sense...

However, what you have just said about a vacuum bottle makes absolute perfect sense, heat would not travel off of it.

Lasers will be worthless when the Glitterboys take the field with their boomguns.

But that's fine, because playing one in the Savage Worlds Rifts adaptation is some of the most fun I've ever had in an RPG.

Re: Railguns in space

Thanks to Newton, you’ve got equal and opposite forces applied to your railgun. So whatever force you apply “downwards” is going to push your weapon “upwards”, out of Earth orbit.

Whereas simply dropping a high-density item (tungsten rod / javelin, for example) that will have a higher terminal velocity than a less dense item, can impart Nuclear weapon levels of force without all that nasty radiation. According to Wikipedia, a 9 ton rod is estimated to be equivalent to a 7 kilotonne nuclear bomb.

Admittedly, getting a 9 ton rod into space is impractical, but several 1 ton rods hitting earth at approximately Mach 10 (3 km per second) could easily wipe out a city. More joyous thoughts brought to you by 2020...

No heat worries, no moving parts per se... just a big stick you let go of at the right time and angle.

endlesswaltz123 wrote:

Spoiler:

 Laughing Man wrote:

 RiTides wrote:

 A Town Called Malus wrote:

endlesswaltz123 wrote:
Such heat generation possibly won't be as much of a huge issue in space (this is me putting 2 and 2 together by the way, not an engineer) as space will be the ultimate heat sink.

This actually backwards. Space is terrible for getting rid of excess heat as the only method of losing heat in space is via radiation as there is no medium for a hot object to interact with and so you cannot use convection.

Really? I also would have thought the opposite... space is just above absolute zero, so even just with radiation I would have thought it'd be really effective... will have to look into it more, as now I'm super curious

Space isn't cold. It also isn't hot. It's not anything, simply because it's completely empty. There's no stuff to be warm or cold. It's the same reason that drinks in a vacuum bottle stay scalding hot for hours: There's nowhere for the heat to go except via radiation, which is an extremely inefficient way to lose heat. So any heat you generate will stay there, and compound extremely rapidly.

When ATCM mentioned convection I knew it sort of made sense...

However, what you have just said about a vacuum bottle makes absolute perfect sense, heat would not travel off of it.

Some games and other fiction handle this by dumping the excess heat into a heatsink, and dropping that overboard. More objects to avoid, but you'll be able to see it coming.

 greatbigtree wrote:
Re: Railguns in space

Thanks to Newton, you’ve got equal and opposite forces applied to your railgun. So whatever force you apply “downwards” is going to push your weapon “upwards”, out of Earth orbit.

Whereas simply dropping a high-density item (tungsten rod / javelin, for example) that will have a higher terminal velocity than a less dense item, can impart Nuclear weapon levels of force without all that nasty radiation. According to Wikipedia, a 9 ton rod is estimated to be equivalent to a 7 kilotonne nuclear bomb.

Admittedly, getting a 9 ton rod into space is impractical, but several 1 ton rods hitting earth at approximately Mach 10 (3 km per second) could easily wipe out a city. More joyous thoughts brought to you by 2020...

No heat worries, no moving parts per se... just a big stick you let go of at the right time and angle.

"Rods from god" aka "Blessed are the THOR satellites".

”...team leader on the project, Dr Steve Rogers of the Air Force Research Laboratory (AFRL)...”
Am I the only one who thought Captain America is building AI fighter jets?

 greatbigtree wrote:
Re: Railguns in space

Thanks to Newton, you’ve got equal and opposite forces applied to your railgun. So whatever force you apply “downwards” is going to push your weapon “upwards”, out of Earth orbit.

Whereas simply dropping a high-density item (tungsten rod / javelin, for example) that will have a higher terminal velocity than a less dense item, can impart Nuclear weapon levels of force without all that nasty radiation. According to Wikipedia, a 9 ton rod is estimated to be equivalent to a 7 kilotonne nuclear bomb.

Admittedly, getting a 9 ton rod into space is impractical, but several 1 ton rods hitting earth at approximately Mach 10 (3 km per second) could easily wipe out a city. More joyous thoughts brought to you by 2020...

No heat worries, no moving parts per se... just a big stick you let go of at the right time and angle.

Sure, there would need to be thrusters to counteract the recoil, but a satellite is going to need those anyway. But yes, it is easier to simply drop some steel beams from orbit.

The space shuttle was capable of carrying a 60k pound payload. That's 3 rods if you used a Space Shuttle to do it, but you could cut that out entirely and go with a 1 way rocket that could carry a larger payload and just get the rods into orbit, then you have some little thruster drone pick them up and install them into the bombardment satellite.

plus, I don't think the Rod concept is as impractical costwise as people might think. The costs for a Space Shuttle mission are also actually fairly comparable to the costs for an ICBM, with the bonus that a Rod delivery mission can be fully automated and doesn't need people to carry out. And since you'd be getting multiple shots with a weapon comparable to an ICBM I think it would be far more cost effective. With the bonus that it needs basically no maintenance unlike an ICBM.

Railguns would be useful for defending the planet against asteroids though I think, and shooting down enemy satellites too.

.across the gulf of space, minds immeasurably superior to ours regarded this earth with envious eyes, and slowly and surely drew their plans against us

A green glow has appeared around Mars


... least we've already got the virus for'em ready and good to go

Unfortunately (or fortunately, I guess), KKWs do a lot less damage than your average nuke. That ten ton rod going at 3 km/s has 45 gigajoules of energy, which is pretty much all deposited directly into whatever it lands on. A one megaton bomb releases about 45 petajoules of energy, a million times more and omnidirectionally. You're generally better off just throwing a one ton bomb out of the back of a plane.

 Laughing Man wrote:
That ten ton rod going at 3 km/s has 45 gigajoules of energy, which is pretty much all deposited directly into whatever it lands on.

The bolded part is the key takeaway, and what makes the rods worth it.

Nukes are pretty inefficient in terms of energy conversion. So much of their energy is converted into useless light and long term radiation instead of pure explosive force. Now maybe you want the area denial that the long term radiation gives, but generally it is not a desirable part of a nuke.

The rods are much more focused with their energy, which in theory makes them better against a hardened target like a deep underground bunker even if they have much less overall energy than a nuke. The rods can also still level cities if you want, and without that nasty radiation to worry about.

For the thought experiment of it, scattering 10x 1 ton rods in close-ish proximity could probably level a small city, while a single 10-ton rod could be used for bunker penetration.

In situations where you want to claim territory in less than several lifetimes, the non-nuclear option has benefits.