Space Warfare - How would the ships be built/designed?

[baggers]

Terrorism is a political activity, not a military activity. It's about advancing a political agenda by causing terror. A terror attack may target civilians or military, but it's always a crime, not a military action.

But isn't a war usually 20% military action, 80% "others"? (propaganda, production, politics, social, economics...)

[GeneralVeers]

I said that the world is full of Cold War-era military forces.

And I disagree. Force organizations during the Cold War were designed around the threat of a war against one major power by another major power. Just because the Cold War is over, doesn't mean that threat is over.

Uhh, by the way? Check your phone. China called.

In general, military technology doesn't usually become obsolete by becoming useless or ineffective. It's more common that technological or tactical development just removes the need for certain specialized systems. For example, main battle tanks are expensive weapons platforms that are specialized for fighting other main battle tanks. If your enemy doesn't have main battle tanks, your main battle tanks become just expensive support vehicles that can perform the role almost as well as much cheaper specialized support vehicles.

Wrong. The invention of the tank was what broke the trench-warfare stalemate of World War I. First and foremost, a tank of any kind is an antipersonnel weapon. Even when armed with antitank weapons and land mines, infantry are at a severe disadvantage against tanks. Especially if the tanks are part of a mixed force that includes infantry.

And then you have inferior tanks that can't be used in combat, because enemy tanks would wipe them out.

Also wrong. If your tanks are inferior to enemy tanks, don't engage the enemy tanks. Have your tanks avoid enemy tank forces, and destroy infantry and factories. That was the doctrine of the Sherman tank during WW2; the Sherman was not designed for tank warfare, it was designed for infantry support. In fact, its cannon shells actually bounced off the armor of German Tigers!

Terrorism is a political activity, not a military activity.

Disagree here also. Terrorists can have many different motivations, whether political or military or plain old loss of hope. Some terrorists, such as the Sandy Hook shooter, are (well, were) nothing more than people with miserable lives who fall into the "misery loves company" trap and want to inflict misery on others.

But yes, it's always a crime, we definitely agree on that!

[Kibble]

Would it be out of line to mention how off-topic this has become? How do tanks and terrorism relate?

[Jouni]

And I disagree. Force organizations during the Cold War were designed around the threat of a war against one major power by another major power. Just because the Cold War is over, doesn't mean that threat is over.

Most of Europe disagrees with you. Pretty much everyone scaled down their military forces and reduced the number of tanks by ~5x. The Soviet threat was over, nobody else could threaten Europe with a major ground war, and the European powers weren't planning to attack anyone either.

Uhh, by the way? Check your phone. China called.

China is far away and lacks the ability to wage a major war overseas.

Wrong. The invention of the tank was what broke the trench-warfare stalemate of World War I. First and foremost, a tank of any kind is an antipersonnel weapon. Even when armed with antitank weapons and land mines, infantry are at a severe disadvantage against tanks. Especially if the tanks are part of a mixed force that includes infantry.

You're still confusing "what tanks are good cost-effective for" with "what tanks are good for". If you assume that some kind of ground-based combat vehicles have a central role in warfare, then tanks are obviously important. On the other hand, if you just sideline the entire concept of ground-based combat vehicles (or even major ground battles), tanks become just an expensive way of doing things that can usually be achieved with cheaper weapon systems.

Also wrong. If your tanks are inferior to enemy tanks, don't engage the enemy tanks. Have your tanks avoid enemy tank forces, and destroy infantry and factories. That was the doctrine of the Sherman tank during WW2; the Sherman was not designed for tank warfare, it was designed for infantry support. In fact, its cannon shells actually bounced off the armor of German Tigers!

That worked in WW2, because realtime battlefield information was scarce. These days, the situation is completely different.

Your tanks may try to avoid enemy tanks. On the other hand, if the enemy knows that their tanks are superior to yours, their tanks definitely won't avoid your tanks. Your tanks may form a serious threat to infantry and fixed facilities, but the enemy can effectively neutralize that threat by using its own tanks. As soon as the enemy sees your tanks, it sends a few tanks of its own to deal with the situation. As a result, you should expect to face heavy casualties whenever you use tanks.

Disagree here also. Terrorists can have many different motivations, whether political or military or plain old loss of hope. Some terrorists, such as the Sandy Hook shooter, are (well, were) nothing more than people with miserable lives who fall into the "misery loves company" trap and want to inflict misery on others.

The Sandy Hook shooting didn't feel like a terror attack at all. It was "just" random violence without any perceivable purpose behind it.

[tater]

No you didn't. You attempted the burden-of-proof fallacy. I didn't fall for it.

Everything in this thread is theoretical, and impossible to subject to accurate testing. To figure out what "should" work in space warfare, all we can do is extrapolate from what we see in the real world. And what we see in the real world is that sand and dust scatter laser beams. That trumps anything you could possibly say.

There is no fallacy. You are claiming that because low-powered lasers are mitigated by transmission through long path lengths of dense sandstorms within an atmosphere, they will similarly be affected by tiny path lengths though less dense sand. You are making a positive claim that the 2 are the same, when they self-evidently are not.

Your example is:

Not in space.

Not the same density of sand.

Not the same path length of obscuration for the beam to travel through.

We can extrapolate from the real world, which is exactly what I did. I took a typical grain size for real particulate matter called "sand" (which is what your real world example is), and calculated how many of those grains exist in a 50kg bag of same (a given for any traveller discussion, that's canon), then provided densities of that sand in space, dispersed over a couple different radii as examples. We could alter the parameters of the sand, say go with a smaller grain size, but we just interact with more, but smaller grains. We could then calculate the optical depth of out sandcaster cloud. We can also mess with how it is deployed (farther away from the launching ship, the cloud could be smaller, as long as it subtends the same angle as your ship to the shooter).

Anyway, it is not a beam traveling through 2+ km of sand+atmosphere, it is a beam traveling though maybe 40 meters of sand with say 0.003 grains of sand per cm of path length. In this example, AT MOST, the beam will interact with 12 grains. Not 12 grams, 12 individual grains. At this same low density, the 2 km path length (not counting atmospheric effects)of a sandstorm example would result in the same beam interacting with 600 grains. Of course real sandstorms have more than a single sand/dust particle for every 333 cubic cm, so the beam would interact with vastly more grains. I've seen real sandstorms described as holding millions of tons of sand while being on the order of 100km across.

We could then find out what the density of a real sandstorm actually is, and go for that in space (minus the (large) atmospheric effects)). Great. Let's use a higher density of sand... but we are only allowed 50kg of sand, because that is a given. So any attempt to make the sandstorm analogy work either requires more sand than we are allowed by canon, or our 50kg must be placed in a very small volume of space near our ship. Neither works, as we'd be stuck deploying the sand into a volume not substantially larger than the canister it came in.

This is what "theoretical" and extrapolating is. I'm not even bothering with super accurate values, sandcasters don't even work at the "order of magnitude" level.

So again, show your work for your positive claim that canon traveller sandcasters would work, because sandstorms mitigate lasers on earth.

The game is silly; the concept is not. Smokescreens, chaff, decoys, and aluminum-foil radar ghosts are tried-and-true combat techniques that will be adapted for space combat.

Chaff possibly useful, active sensors are unlikely to be used much, but they could be used in terminal guidance of missiles, etc. (foil IS chaff, BTW). Decoys are pretty much useless, they need to be as massive as the ship they pretend to be to match acceleration with output. Smokescreens? Adding gasses/particulates seems like a chance to advertise your position, not hide it, though it's not impossible that this could be used to some benefit.

Edited September 13, 2015 by tater

[RandomRyan]

something kerbal, yet destructive.

thats all i can say.

[Jouni]

Would it be out of line to mention how off-topic this has become? How do tanks and terrorism relate?

Tanks are actually quite relevant to the topic. The rise and decline of tanks is a good example of how warfare changes over time. Similar patterns would probably emerge, if you replaced tanks with lasers, missiles, or other space combat technologies. New systems are developed to solve existing problems. Then you need means to counter them, and means to counter the countermeasures. Then something else changes, and your system finds a new role in battle. Then something changes again, and the original problems become much less relevant, sidelining your system.

[tater]

Tanks are actually quite relevant to the topic. The rise and decline of tanks is a good example of how warfare changes over time. Similar patterns would probably emerge, if you replaced tanks with lasers, missiles, or other space combat technologies. New systems are developed to solve existing problems. Then you need means to counter them, and means to counter the countermeasures. Then something else changes, and your system finds a new role in battle. Then something changes again, and the original problems become much less relevant, sidelining your system.

This is so very true, hence my constant whining that such a thread needs a really detailed "universe" to be useful. We need not just TRLs, but geopolitics, economics, and history to really make sense of it.

[GeneralVeers]

There is no fallacy. You are claiming that because low-powered lasers are mitigated by transmission through long path lengths of dense sandstorms within an atmosphere, they will similarly be affected by tiny path lengths though less dense sand.

No I'm not. I'm claiming that since laser test platforms right here on Earth have already failed to perform properly in dusty or sandy conditions, we can infer that laser weapons in space would also fail upon encountering similar conditions. I never specified how long any given path length was, nor how dense any given sandstorm was.

(what you just did is called the "straw man" fallacy, by the way: claiming the opponent said something, when they actually said something completely different)

Would it be out of line to mention how off-topic this has become? How do tanks and terrorism relate?

Unavoidable. In fact, there was no reason to NOT expect that to happen in this particular thread.

The scenario posited by Sanguine in the original post is entirely theoretical. The human race has never fought a space war; we don't know what would actually work. All we can do is extrapolate and guess based on our experience in terrestrial wars fought in the past. So parallels with modern-day technology and tactics are not merely unavoidable, but essential.

Most of Europe disagrees with you. Pretty much everyone scaled down their military forces and reduced the number of tanks by ~5x. The Soviet threat was over, nobody else could threaten Europe with a major ground war, and the European powers weren't planning to attack anyone either.

You're right. The above is exactly what Europe did.

Right before World War II started.

And we all know how that ended, don't we.....?

You're thinking in the same way world leaders were thinking after World War I ended. It wasn't called World War I at the time, it was simply called "The Great War". The world's leaders were determined to prevent another "The Great War" from ever happening again--so they demilitarized. Then Hitler smacked all of them upside the head with World War II, and nobody saw it coming until the tanks were driving right through front doors all over Poland. Only then did World War I end up with a 1 at the end of it. And here we are today, with people thinking that the end of the Cold War means we will have peace in our time. Never mind that minor commotion happening over in the Ukraine; there's no possible way that could evolve into a shooting war between the EU and Russia.........

China is far away and lacks the ability to wage a major war overseas.

I never said "overseas". China vs. Japan, China vs. the Phillipines, China vs. Korea. China has been using military threats to muscle prime territory away from their neighbors, and it's entirely possible their shenanigans will result in a shooting war between China and somebody besides the United States.

You're still confusing "what tanks are good cost-effective for" with "what tanks are good for".

Not at all. Tanks are cost-effective for ground warfare. They combine speed; striking power against a wide variety of targets; and survivability against snipers, shrapnel, and small-arms fire (and, if you stick Chobham armor on them, almost everything else except land mines).

That worked in WW2, because realtime battlefield information was scarce. These days, the situation is completely different.

Your tanks may try to avoid enemy tanks. On the other hand, if the enemy knows that their tanks are superior to yours, their tanks definitely won't avoid your tanks. Your tanks may form a serious threat to infantry and fixed facilities, but the enemy can effectively neutralize that threat by using its own tanks. As soon as the enemy sees your tanks, it sends a few tanks of its own to deal with the situation. As a result, you should expect to face heavy casualties whenever you use tanks.

Okay. You do that. Here's what I do: my "inferior" tanks turn out to be faster than yours, and your tanks are too slow to respond to the threat in time.

Or, my tanks turn around and run away. Yours pursue--right into an ambush.

OR, I purposefully leak a battle plan saying I'm going to lure your tanks into an ambush. Therefore your tanks hold position for fear of getting ambushed, and I get to hit the target unopposed.

But, wait, here's another one! Your scouts inform you that my tanks are attacking from THREE DIRECTIONS at once. What you don't know is, two of those tank forces consist of decoy vehicles made of plywood and being driven by remote control. If you concentrate your tanks on one strike force, I have a two-in-three chance to hit the target unopposed. If you split your forces, the one-third of your tanks attacking my real tanks will be badly outnumbered.

The above scenarios aren't just armchair quarterbacking, either. All of the above have already happened in warfare, many times.

The Sandy Hook shooting didn't feel like a terror attack at all. It was "just" random violence without any perceivable purpose behind it.

Key word being "perceivable". There was a purpose--it's just that you don't know what it is. I theorize that if a mass murderer's wish is simply to make people afraid and miserable, the best way to do that is to specifically do something that IS completely senseless.

[Rune]

No I'm not. I'm claiming that since laser test platforms right here on Earth have already failed to perform properly in dusty or sandy conditions, we can infer that laser weapons in space would also fail upon encountering similar conditions. I never specified how long any given path length was, nor how dense any given sandstorm was.

(what you just did is called the "straw man" fallacy, by the way: claiming the opponent said something, when they actually said something completely different)

Ok, I have to comment on that sandcaster nonsense. What on Earth makes you think that would work better than the same mass, used as a solid plate of ablative armor? For starters, you save on the weight of the ejector, which is invested into more tungsten/C-C composite. As you deposit laser energy on a piece of ablative armor, it vaporizes and a cloud of plasma starts to form, absorbing the heat deposited on the armour plate and de-focusing the laser beam, forcing it to spend more and more energy away from the plate (unless it's pulsed so the plasma can escape between pulses). A "sandcaster", on the other hand, assuming it fires before the laser, would only intercept a fraction of the incoming beam, and the grains that got converted into plasma would push themselves away from the beam path. All the unused armor is not available to contribute to stop the next shot, too.

The above scenarios aren't just armchair quarterbacking, either. All of the above have already happened in warfare, many times.

Yup, that has happened. So have single combatants challenges between champions. Do you think the spaceships will dock so their commanders can slug it out, honorable style? This is like extrapolating cavalry tactics from the middle ages, and them applying them to fight an air battle today: totally different environments call for totally different rules of engagement.

Rune. Sorry if that sounds a bit harsh, but man that sandcaster idea is such a bad one...

[Scotius]

Have you guys seen what Apache helicopter or A-10 Warthog can do to a tank with one missile or a second long salvo from a Gatling gun? If you are fighting an opponent with a decent air force, before you send your tanks in the field first you have to gain aerial superiority. Otherwise you are sending your men to death already packed into ridiculously expensive moving coffins.

[Jouni]

You're right. The above is exactly what Europe did.

Right before World War II started.

And we all know how that ended, don't we.....?

You're thinking about the UK, Netherlands, and Belgium, not Europe.

Europe increased military spending and tank construction significantly before WW2. Otherwise there would not have been a WW2. When Germany attacked France, the French actually had more tanks tanks than the Germans. Still, the French lost, partly because they had guessed wrong how tanks should be used in a major war. Spain was fighting a civil war, while Italy was trying to build an empire by conquering other lands. Hungary and Romania had significant military forces, but they chose to side with the Axis powers. Poland, Chechoslovakia, and Yugoslavia (among others) were recently created countries that never managed to build significant economic or military power before the war started.

Never mind that minor commotion happening over in the Ukraine; there's no possible way that could evolve into a shooting war between the EU and Russia.........

Russia does not have the military or economic power to threaten Europe without using nuclear weapons. It may be able to threaten the unfortunately situated Baltic states and Moldova, but Poland and Romania are already strong enough to oppose Russia with their allies.

Increased military spending in the Western/Southern Europe would just mean that those countries were preparing to defend themselves against the US. After all, the US is the only power in the world capable of presenting a serious threat to them.

I never said "overseas". China vs. Japan, China vs. the Phillipines, China vs. Korea. China has been using military threats to muscle prime territory away from their neighbors, and it's entirely possible their shenanigans will result in a shooting war between China and somebody besides the United States.

Those countries are the exceptions to the rule I mentioned. You only need to be prepared for an old-fashioned ground war, if you have a potential enemy that's preparing for such war. Most of the world doesn't have such enemies.

Not at all. Tanks are cost-effective for ground warfare. They combine speed; striking power against a wide variety of targets; and survivability against snipers, shrapnel, and small-arms fire (and, if you stick Chobham armor on them, almost everything else except land mines).

But is large-scale ground warfare cost-effective for achieving your political goals? Most of the world thinks otherwise. That's why I say that tanks aren't cost-effective.

The above scenarios aren't just armchair quarterbacking, either. All of the above have already happened in warfare, many times.

Those scenarios are all very specific. I could respond with a bunch of equally arbitrary and equally pointless scenarios, but it wouldn't advance the discussion.

The main point remains. Because your tanks are vulnerable high-value targets, you risk heavy casualties every time you're using them. That's why you won't use more than a few tanks outside critical battles, just like how tanks are being used in the Syrian civil war.

Key word being "perceivable". There was a purpose--it's just that you don't know what it is. I theorize that if a mass murderer's wish is simply to make people afraid and miserable, the best way to do that is to specifically do something that IS completely senseless.

Random violence doesn't make people afraid. It's like an act of nature. People die, but because you can't see any purpose behind it, you just learn to ignore it and keep going.

[tater]

No I'm not. I'm claiming that since laser test platforms right here on Earth have already failed to perform properly in dusty or sandy conditions, we can infer that laser weapons in space would also fail upon encountering similar conditions. I never specified how long any given path length was, nor how dense any given sandstorm was.

Yes, but those conditions are NOT similar, and I explained why, in detail. Your argument is exactly "wings work on earth, so they should also work just as well in space."

The path length is exactly what matters. Shooting a laser within a sandstorm is NOT the same as shooting one though no air, then through a couple meters of sandstorm. 50 kg of sand is a GIVEN. That is a traveller sandcaster reload. You are welcome to calculate what volume of space you can cover to exactly replicate a terrestrial sandstorm (including atmospheric effects) with 50kg of material to work with. Then we will know how much of a ship we can protect. If it is less than 100% of the (player-sized) ship, then it's not right. I gave the benefit of the doubt and only used a Scout Courier which is just under 40m long (I think its 37), but it works for all ships under 1000 dtons.

Another example that is EXACTLY analogous to what you are saying. The earth's atmosphere slows a projectile via drag. We can measure the range of a bullet's effective (can still kill) range. Say it's 2000m for argument. Can I release air into space next to my ship, and stop a bullet? Sure, If I add the gasses so that the bullet goes through 2000m of that same density of gas. What if my canister of air only makes a sphere 100m thick? I'm not stopping the bullet, I'm just going to slow it during that 100m.

I found a reference to a sandstorm covering 134km^2, and carrying 6.5 million tons of sand/dirt. They did not list the altitude. Assume it is 8km high (26,000 ft), that's around 6 kg/m^3 of dirt, so our sand canister would have to deploy to a 1.26m radius sphere to match that density. The volume is a cube, so we need a LOT more sand to make this radius reasonable to cover a ship, then we still need to decide how far into the sandstorm the laser penetrates.

(what you just did is called the "straw man" fallacy, by the way: claiming the opponent said something, when they actually said something completely different)

Untrue, and that is not a straw man. A straw man is making a fake argument that the opponent did not make that is easy to defeat, then defeating it yourself. If the opponent makes such an easy to defeat claim, and you defeat it, it's not a straw man.

You are arguing that the fact of lasers not being effective in sandstorms is exactly the same as traveller sandcasters in space, even though they use very small amounts of sand. Your argument IS easy to defeat, I am not putting words in your mouth at all.

We have 3 givens. One, 50kg of "sand" to make your defense. Two, it must be possible for this to be 100% effective much of the time vs at least a single laser. Three, the lasers deliver multiple MJ per square cm.

Is it possible to make a 100% effective "sandstorm" that is plausible using 50kg of particles?

I would argue that it is not plausible, for reasons laid out above.

Edited September 13, 2015 by tater

[shynung]

Have you guys seen what Apache helicopter or A-10 Warthog can do to a tank with one missile or a second long salvo from a Gatling gun? If you are fighting an opponent with a decent air force, before you send your tanks in the field first you have to gain aerial superiority. Otherwise you are sending your men to death already packed into ridiculously expensive moving coffins.

Yep. Though, to be fair, aerial superiority can be achieved by either fighter jets or AA systems. So even a combatant group not having an access to aircrafts could deny the use of their opponent's air assets.

[GeneralVeers]

Ok, I have to comment on that sandcaster nonsense. What on Earth makes you think that would work better than the same mass, used as a solid plate of ablative armor?

Simple: when you want to soundproof a room, what do you encase it in? Solid steel armor? Nope. Spongy insulation. Curtains. Cloth wall-hangings. Materials that disperse and scatter sound waves.

Light is similar. What you want with a laser is something that scatters and disperses the beam. And that doesn't conduct the heat into your ship's armor.

Yes, but those conditions are NOT similar, and I explained why, in detail.

Your explanation was bogus and irrelevant and littered with red herrings. The only conditions that matter are these: a laser is going through a cloud of sand, or dust (or an actual cloud). What happens? The beam is scattered to the point where its damage output becomes negligible.

Untrue, and that is not a straw man. A straw man is making a fake argument that the opponent did not make that is easy to defeat, then defeating it yourself.

And that's what you did. Knock it off.

You're thinking about the UK, Netherlands, and Belgium, not Europe.

I'm thinking about the whole enchilada. With guacamole. Europe being the guacamole in what is turning out to be a really bad analogy.

Whether or not Europe increased military spending before World War 2 (my history books disagree) is irrelevant to the fact that Europe clearly didn't have enough troops and spent a bunch of their funds on the wrong things (such as the Maginot Line). The entire reason I brought up World War 2 in the first place was to point out that Europe was caught completely off-guard. Just as you will be, next time a major war involving Europe breaks out. Just because the Cold War is over does NOT mean its tactics (and its weapons) are obsolete.

The tank is not obsolete. Though, as Scotius pointed out, it does have vulnerabilities. There is no one perfect weapon system; everything (even a Death Star.....) belongs in a mixed force.

Russia does not have the military or economic power to threaten Europe without using nuclear weapons.

Yes it does. Because the Russians have one very important piece of military hardware, that Europe does not.

A backbone.

Inferior weapons can (and currently do) pose a huge threat if the people staring up the barrels are afraid to shoot back.

But is large-scale ground warfare cost-effective for achieving your political goals? Most of the world thinks otherwise.

If my political goals included conquest? Absolutely. Tanks for the win. Plus supporting infantry and air power. The reason most of the world thinks otherwise is because most of the world isn't trying to conquer the rest of it. The one entity that is (hint: it's in the Middle East, and it starts with an "I") is an army of morons who don't know how to drive/repair/maintain tanks.

Those scenarios are all very specific. I could respond with a bunch of equally arbitrary and equally pointless scenarios

They're not pointless, because they HAVE been used in past wars. With great success, and repeatedly.

The main point remains. Because your tanks are vulnerable high-value targets, you risk heavy casualties every time you're using them.

Aha! Thank you for reminding me. That's another good military tactic: give your opponents a big, scary target that they will waste firepower on, while ignoring the flank maneuver coming in on their side......

Random violence doesn't make people afraid.

Every time I read about a school shooting in the news, people say the exact opposite. So I disagree. Random violence is one of our worst fears--precisely because it's random. That which cannot be known or predicted is exactly what scares us the most.

[Rune]

Simple: when you want to soundproof a room, what do you encase it in? Solid steel armor? Nope. Spongy insulation. Curtains. Cloth wall-hangings. Materials that disperse and scatter sound waves.

Light is similar. What you want with a laser is something that scatters and disperses the beam. And that doesn't conduct the heat into your ship's armor.

Ablative armor. Meaning first you have to provide enough heat to vaporize it, then it starts to scatter your laser light just like your sand is supposed to do. Dude, that is like laser protection 101, make the beam spend its energy somewhere with a high latent heat of vaporization but low conductivity. And making comparisons to sound waves is a totally flawed metaphor, starting with air being the actual acoustic insulator, not the foam. Do you even know what happens when a weapons-grade laser hits something? Scattering is like a third order effect, that mainly affects targeting lasers on an atmosphere. Pulsed high power lasers are actually pulsed to leave the shockwaves of each pulse to do extra concussive damage. How do you say that you keep your sand in place between pulses?

Rune. Don't tell me, next you'll suggest mirrors.

[tater]

Your explanation was bogus and irrelevant and littered with red herrings. The only conditions that matter are these: a laser is going through a cloud of sand, or dust (or an actual cloud). What happens? The beam is scattered to the point where its damage output becomes negligible.

It;s not the least irrelevant.

You are now saying the effects of sand and atmosphere on earth on a laser are IDENTICAL to just sand/dust in space, regardless of the density of the latter?

If that is NOT the case, explain what you mean. Be precise.

And that's what you did. Knock it off.

Nope, you are doing it to yourself by "doubling down" on an analogy that is somewhat useful as a baseline, but entirely different in specifics.

You have 50 kg of sand/dust/whatever to spread. Make it equal a sandstorm in space. How big is the cloud? Show your work.

[Scoundrel]

If I may be permitted to offer my humble and worthless internet opinion on the sand caster idea?

Firstly, there's nothing stopping the sand from expanding into a cloud of uselessness since the cloud would have to be deployed quickly lest the lasers do serious damage. Sand has no means of controlling its velocity once it is ejected from the vessel. It won't form a protective cloud of anything because it disperses to meaningless densities within a matter of seconds... actually, likely tenths of a second. The reason? There's nothing slowing the sand down!

...unless someone is suggesting nano-rcs for each grain of sand so it holds its position perfectly... and I don't think anyone here is trying to say that. Remember, we're talking about the near-vacuum of space where the only thing that would affect the sand is gravity and whatever the sand happens to impact. Newton's laws of physics and all that.

Don't believe me? Try this fun experiment: open up KSP, build a ship with a whole bunch of TR-2V decouplers (or TR-2C... whichever you prefer) rigged up to a handful of cubic octagonal struts to expand into a multidirectional "protective anti-laser cloud" and set them to all go off to an action group. Get the ship into orbit (without exploding... not exploding is important!) and activate it. Count how many seconds your cloud of anti-laser decouplers lasts as an effective "cloud". Betcha it's a small number.

Secondly, you've just scattered a solid substance into your orbital path that is travelling at dangerous velocities - maybe not to you, but to future crafts, or even your "wingmates" who may be trying to join you and are travelling at much higher or lower velocities while trying to get to your position. Ouch! You've effectively created an small area of denial weapon that, depending on your orbit, could last for decades before its orbit decayed enough to be considered safe. Grains of sand travelling at thousands of meters per second are bad news! This alone would probably make space naval architects throw the idea out the window.

Or weaponize it.

Thirdly, what about sand getting into the combustion chambers of various maneuver thrusters, or even your main engines? Sensors? Weapons? Radiators? I personally cannot imagine many scenarios where a high velocity debris field in space is a good thing for anyone near it. Imagine what it would do to the optics of your lasers as they sandblast your protective coatings off it, or, heaven forbid, scratch those precious optics!

Lastly, as great a sci-fi author's solution as it is, a sand cloud to counter laser weaponry pre-supposes that the sand cloud, however briefly (what with the sand flying in all directions in the vacuum of space), is dense enough to scatter the laser for a meaningful amount of time. Now scattering a low power designating IR laser with a bucketful of sand in space would be easy, but a high power pulse laser weapon would likely burn through the cloud with ease: if we can burn a 5mm hole in the 10mm thick hull of a warship in 1/10th of a second at tens of thousands of kilometres distance - so 1700°C+ for titanium alloys, likely closer to 2000°+ for warships - then we can vaporize a handful of particles of sand at 1650° (assuming quartz rather than silicon, which would be 1414°C) without even remotely effecting our ability to cut a neat little hole in a hull; heck, depending on its wavelength, the laser could ignore the sand all together!

In summary, I believe the sand caster would likely make a fantastic orbital area denial missile warhead... and not much else.

Edited September 15, 2015 by Scoundrel

[baggers]

About stealth in space (again, yes).

We have today, small railguns capable of suborbital shots. So imagine a big railgun capable of orbital, and interplanetary shots.

http://forum.kerbalspaceprogram.com/threads/134317-Big-guns-in-space

A "regular" ship can carry and power that sort of railgun, and retain some mobility: it's an "interplanetary warfare mobile platform", isn't? ^^

So, next stage is: a nuclear submarine armed with an interplanetary railgun. Stealthy!

Thinking of that, a underwater species/civilisation will be a real pain to fight ^^.

Next, a submarine capable of interplanetary travel for hiding itself on Titan Kraken Mare!

[tater]

Snipped a bunch of good stuff.

All true. Later versions of the rpg hand-waved some sort of "gravtic" control of the cloud to maintain it (like a tractor beam) since they had artificial gravity (they wanted Star Wars-like ships where you can walk the decks under acceleration).

I read a few papers last night on High Energy Lasers... the Navy is doing a lot of work on these. Looks like delivered power (simulations and tests tend to standardize on a 5km range, and look at a 100cm^2 target area for the beam) is about 1/2 to 1/3 of transmitted power in both a maritime and desert environment. The latter includes dust, but not a "sandstorm." This shows how profound even nominal atmospheric effects are on laser weapons. At 5km in space, this would be mostly diffraction and jitter limited, instead (there is a small particle density, obviously). A huge difference, right off the bat.

Their description of dust vs water vapor or other aerosols suggests that the dust is a problem because the beam doesn't vaporize it, but heats the particles which heat the surrounding air, causing thermal blooming. In space, the particles are heated, but there is no air to heat and cause the blooming.

Interestingly, they also did simulations from a 5km altitude firing DOWN through maritime and desert conditions, and the delivered power ration is somewhat better, as you would expect (shorter path-length through the higher density air/dust near the surface). They approached 60% of the power delivered to the target in that regime.

In general in the atmosphere (sea level), propagation efficiency plummets after 3-5km (the latter with adaptive optics). By 12-15km, it's well under 20%, and effectively zero for non-adaptive optics.

Without question, atmospheric densities of gases and aerosols over kms would seriously hamper laser weapons, but you need reasonable path-lengths though those areas. If a ship needs to haul around thousands of tons of gas/dust/sand to have the system work, it doesn't make much sense. It would also pose a navigational hazard (hitting it with any decent closing velocity would scrub your hull for you).

[cicatrix]

Personally, I thihk that there is nothing in space worth fighting for. For now, perhaps. Modern technology offers very limited options and most of the solutions are so expensive (with possible exception perhaps of a bucket full of nails put into a retrograde orbit) that they would sooner banrkupt the party who tries to use them thus ending the war before it begins.

Before venturing any further - any combat is a sequence of tactical decisions usually made before the engagement and usually all of them go down the toilet as soon as the actual fighting starts. The problem is that even modern-day hi-tech warfare requires decision making at speeds no human can even dream of achieving so it comes down to the computers. Here we come to a conclusion - it is extremely ineffective to have human crew onboard any war spacecraft because computers are faster, cheaper and require nothing but electricity to operate.

So, even if something in space would ever require fighting it will come down to drones vs. drones. I also think that it's more practical to make lots of light cheap expendable (probably one-time kamikaze-like) drones that interact with each other like bees than to make big armored vessels. So, as I see it - a container of relatively-light drones (missiles if you like) is delivered into a designated area then they spread and start searching for enemies. After a target is aquired, one of them (or several) start towards it and explode on contact. Of course, enemy drones will try to engage the attackers and send interceptors, etc. Whoever has more drones wins.

[Scoundrel]

All true. Later versions of the rpg hand-waved some sort of "gravtic" control of the cloud to maintain it (like a tractor beam) since they had artificial gravity (they wanted Star Wars-like ships where you can walk the decks under acceleration).

Yeah, I played some Traveller (along with Star Frontiers, FASA's Star Trek, Aliens, d6 Star Wars, Space Master 1st & 2nd Ed, GURPS, SFB, blah blah blah, but finally settled on BattleTech and WH40K: rogue trader... dating myself there! ) though I always thought they had the star wars/star trek stuff in there from the beginning. Then again I only dabbled a little and have no clue what edition I played, so I'm no authority.

Anyways, if you have the ability to manipulate objects through gravity via tractor beams and other handwavium powered devices, then you don't need sand. You just throw a gravitic "shield" in the path of the laser and simply bend it away from/around the vessel.

<snipped cool laser stuff>

I'm hardly an expert on lasers (my knowledge is admittedly limited to designating lasers and whatever I read on Winchell's Atomic Rocket's site), but I suspect that we'd find that, in the future, weaponized lasers are inferior to other, more thermally efficient weapons because heat management will be the primary limiting factor in warship capability. Plus I don't believe a ship-based laser battery could dramatically overheat a warship designed for space superiority/dominance: the volley of hyper-velocity tungsten annular blast warhead shells fired from the lased vessel's mass drivers would tear the lasing vessel in half well before the heat became an issue.

Now, in terms of hull integrity, those lasers could possibly burn their way through and do some damage in the meantime, but I suspect lasers that burn holes and lasers that just heat ships up to overload their cooling systems will likely be two different kinds of lasers: one fired from ships, the other fired from ground or large "stationary" orbital installations.

Personally, I suspect lasers would be restricted to point defence and sensor blinding/EW duties, though I could see atypical wavelength lasers being used to irradiate crew members, or disable electronic systems like some experimental lasers do now. I might even go a step further and speculate that future armour systems will be what dictate which weapons systems end up being the best primary armament.

[tater]

Yep, as a few have said (myself included), the exact universe/scenario needs to be specified since technologies don't exist in a vacuum. Measures, and countermeasures, etc, as nauseum.

[GeneralVeers]

Ablative armor.

That's one way, and something that I think has already been mentioned in this thread. Something else I'm sure you're familiar with: reactive armor. When a shell, RPG, kinetic penetrator, HEAT round, or whatever else hits reactive armor, an explosive charge under the armor goes off; this small explosion foils explosive shells and RPG's, knocks kinetic penetrators out of alignment, disrupts the molten jet administered by HEAT rounds, etc. Effectively, reactive armor is knocking the outer armor layer away from the target so the impact of the weapon doesn't contact the hull. If the tank armor is built as a grid of small tiles, the reactive-armor detonation of one tile leaves the rest of the armor intact.

Sound familiar? Reactive weapon? Not in contact with the hull? The basic concepts already exist on the modern battlefield.

Meaning first you have to provide enough heat to vaporize it, then it starts to scatter your laser light just like your sand is supposed to do. Dude, that is like laser protection 101, make the beam spend its energy somewhere with a high latent heat of vaporization but low conductivity. And making comparisons to sound waves is a totally flawed metaphor, starting with air being the actual acoustic insulator, not the foam. Do you even know what happens when a weapons-grade laser hits something?

If the target is a plane, drone, artillery shell, or ICBM warhead, what usually happens is a few seconds of laser exposure causes part of the target's hull to melt and/or break off. The loss of aerodynamic streamlining then causes the target to tumble out of control and break up. We've got a long way to go before the energy delivered per unit time is enough to explode a TIE fighter with a millisecond laser burst.

How do you say that you keep your sand in place between pulses?

I never did. And the answer is, you don't. Just as with reactive armor, a sandcaster would be a one-shot emergency countermeasure. It buys you a couple of seconds to change course, fire back, or get the warp drive online. Or, at the very least, it forces the enemy to spend twice as much time hitting you with the laser before killing you and turning the laser turret on your squadmates. If you can cut the enemy's kill rate in half, that's definitely worthwhile.

Rune. Don't tell me, next you'll suggest mirrors.

Don't need to. Somebody else already did.

It;s not the least irrelevant.

You are now saying the effects of sand and atmosphere on earth on a laser are IDENTICAL to just sand/dust in space, regardless of the density of the latter?

That should be obvious. Sand and dust will always scatter and disperse a laser beam. Doesn't matter where. On Earth, in space, on the Moon, in the bloody Epcot Center.

Don't believe me? Try this fun experiment: open up KSP, build a ship with a whole bunch of TR-2V decouplers (or TR-2C... whichever you prefer) rigged up to a handful of cubic octagonal struts to expand into a multidirectional "protective anti-laser cloud" and set them to all go off to an action group. Get the ship into orbit (without exploding... not exploding is important!) and activate it. Count how many seconds your cloud of anti-laser decouplers lasts as an effective "cloud".

LOL. Did you really think a KSP player like me hadn't done something like that already?

You engineered it wrong. You forgot to turn the explosive force of the decouplers to minimum. Or, better yet, use Clamp-o-trons. With near-zero ejection force. When you eject the debris screen, it moves away from the ship at near-zero velocity.

So, at the risk of sounding cliche'--"been there, done that".

Secondly, you've just scattered a solid substance into your orbital path that is travelling at dangerous velocities - maybe not to you, but to future crafts, or even your "wingmates" who may be trying to join you and are travelling at much higher or lower velocities while trying to get to your position. Ouch! You've effectively created an small area of denial weapon that, depending on your orbit, could last for decades before its orbit decayed enough to be considered safe.

Seeing as how the human race is already doing this, has already created an orbiting cloud of dead satellites dense enough to be a hazard to new satellites (and, also, probably a hazard to alien spacecraft, which is probably the real reason they haven't invaded Earth......) and is still continuing to fire new junk into space without caring about the problem.......

"Been there. Done that."

Grains of sand travelling at thousands of meters per second are bad news! This alone would probably make space naval architects throw the idea out the window.

Or weaponize it.

Lastly, as great a sci-fi author's solution as it is, a sand cloud to counter laser weaponry pre-supposes that the sand cloud, however briefly (what with the sand flying in all directions in the vacuum of space), is dense enough to scatter the laser for a meaningful amount of time. Now scattering a low power designating IR laser with a bucketful of sand in space would be easy, but a high power pulse laser weapon would likely burn through the cloud with ease

That's just the thing. This whole thread is theoretical, and we don't know how powerful a Terran high-end laser weapon would be.

[tater]

That should be obvious. Sand and dust will always scatter and disperse a laser beam. Doesn't matter where. On Earth, in space, on the Moon, in the bloody Epcot Center.

The problem is that you need to demonstrate that 50kg of sand can be a 100% effective defense against lasers, as it is in traveller.

I showed in even more detail that this is not the case. USN testing and simulation shows that weapons (that are still effective, BTW) lose 50% of their transmitted power just from the AIR, and that the primary effect of dust is thermal blooming (an atmospheric effect).

In the real world, terrestrial laser tests have 100% of the laser path length inside the atmosphere.

Once agin, in the sand caster case, the "sand" (it might be highly variable in composition) cannot possibly interfere with the laser for more than a few meters. This is not remotely the same as multiple km path lengths through aerosols/dust reducing the delivered power, for simple quantitative reasons (not to mention the coexistence of atmospheric effects by definition).

And dispersed "sand" composition would have to have a mixture of particles, as well, each designed with maximum efficacy vs specific wavelength ranges. This means the density of effective particles is even smaller, as once again, you need to make your cloud with just 50 kg canisters.

Can't you just do the math and show how these are effective? You MUST do this to make the positive claim that 50kg of sand dispersed near a ship is as effective as a sandstorm with possibly millions of tons of sand/dust in the air. That IS the claim you are making, that targeting lasers don't work in sandstorms, therefore High Energy Lasers in space are defeated by 50kg of dispersed sand. That is what we are discussing, the efficacy of traveller sandcasters.

Any more realistic analog in space is not dissimilar, the only real variable there is the wavelength, transmitted power and beam size of the lasers int he real world, sand is still just sand.