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Old 02-10-2019, 10:51 AM   #51
Fred Brackin
 
Join Date: Aug 2007
Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

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Originally Posted by Rupert View Post
An increase in percentage hits seems odd, and suggests not comparing like with like.
The article that had this factoid said it was because the framework that held the 6 barrels of the Gatling together made the whole assembly more rigid and thus rediced vibration compared to a single barrel.

There might also have been a difference in motor-driven v. recoli-operated.

So it wasn't comparing like with like but there are sharp limits in how high you can push ROF with a single barrel.
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Old 02-10-2019, 04:57 PM   #52
Michael Thayne
 
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Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

One very important feature of the tactical combat system is that it potentially allows longer high speed engagements that aren't quite fast passes. This potentially makes interdicting traffic in deep space much more feasible. An attack force that might have a 50% chance of destroying a civilian freighter in a fast pass might see its odds of success increase to 7-in-8 (87.5%) if you use tactical combat in way that allows three rounds of missile fire. This is even more important if you're relying on beams (which I'm not sure you'd want to do, but if).

The one really complicated scenario, I think, is if say America and China are both rushing warships to Saturn to control the helium mining there. Does it matter who gets there first? How do logistical issues, particularly the need to resupply missiles and reaction mass, affect things? Do you even bother trying to resupply drones or do you just let them be orbital weapons platforms until they run out of missiles (at which point they're still useful as comm/sensor relays). That's actually a place where things might get fairly strategically rich.

Hmmm, though all that's assuming not many forces are deployed to Saturn when the shooting starts. If Earth orbit is by far the most heavily militarized place in the Solar System, whoever wins probably has an unshakable hold on Earth orbit. But if forces are more spread out, and there's a risk that a fleet that had been hanging out near Saturn (or Mars, or the belt, or whatever) might counter-attack, suddenly Earth orbit gets trickier to manage because it's not just about winning but keeping your winnings. Of course, Earth is right there for resupply purposes, but depending on interface tech it might be cheaper to resupply with stuff manufactured in, say, the asteroid belt. So even that gets complicated.
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Old 02-10-2019, 11:21 PM   #53
Michael Thayne
 
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Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

So about that scenario where you've lost in Earth orbit but what to retaliate against your enemy's helium-3 mining operations (likely in Saturn orbit but possibly elsewhere). There are a number of possible ways you could structure a helium-3 mining operation, but relying on a station in low Saturn orbit (like Cassini station in Transhuman Space). The question of how you'd attack such a station is surprisingly complicated.

One technique would be to drop some drones into a resonant orbit going in the opposite direction, so you can make repeated passes against the station at high relative velocity, ideal for missile attacks. However, I'm unclear on whether such a strategy is possible given Saturn's rings—maybe you could avoid them by using a slightly inclined orbit? Wikipedia says they're 1 km thick at their thickest, but I don't know if there are significantly elevated impact hazards at greater distances from Saturn's equatorial plane.
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Old 02-11-2019, 06:20 AM   #54
AlexanderHowl
 
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Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

The problem with a resonant opposing orbit is that the station defenses have a similar advantage against your spacecraft. A smart major power will also seed the rings with two dozen SM+8 automated defensive batteries camouflaged with ice armor. With ten tertiary missile batteries, six sections of ice armor, two VRF tertiary gun batteries, a control room, and a tactical comm/sensor array, they would carry 2,100 20cm missiles and 84,000 2.5 cm rounds each. Since the opposing orbital velocities would be 20 mps, even the 2.5 cm rounds would deal 6d×10+40 damage.
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Old 02-11-2019, 10:51 AM   #55
Fred Brackin
 
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Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

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Originally Posted by Michael Thayne View Post
So about that scenario where you've lost in Earth orbit but what to retaliate against your enemy's helium-3 mining operations (likely in Saturn orbit but possibly elsewhere). There are a number of possible ways you could structure a helium-3 mining operation, but relying on a station in low Saturn orbit (like Cassini station in Transhuman Space). The question of how you'd attack such a station is surprisingly complicated.
If you can be patient and your target is in a fixed orbit you can design a drone for stealth and launch it from a distance on a space probe-like trajectory.

In specific Spaceships terms you need to avoid the case where your opposition is observing your launching vehicle. That grants automatic detection of any missiles launched by that ship (even that is probably a not entirely realistic assumption for play balance and simplification). If you don't see the launching ship when it launches you need to spot the missiles themselves with their much smaller SM.

Your space probe-like impactor doesn't have to be much more than some tanks of cold gas for maneuevering/course adjustment, a small computer brain with a small battery and a lot of radar absorptive material. It could have a very low thermal signature.

For reasons such as this I tend to think that large stations in fixed orbits are a feature for settings with very low amounts of major conflict or even terrorism. Without superscicnee thay can be extremely hard to defend.

You could make your "stations" not stationary by giving them a propulsion system and making small random changes in their orbits at relatively frequent but allso random intervals. Doing this for rotating stations does get more complicated.
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Old 02-11-2019, 11:13 AM   #56
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Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

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Originally Posted by Fred Brackin View Post
If you can be patient and your target is in a fixed orbit you can design a drone for stealth and launch it from a distance on a space probe-like trajectory.

In specific Spaceships terms you need to avoid the case where your opposition is observing your launching vehicle. That grants automatic detection of any missiles launched by that ship (even that is probably a not entirely realistic assumption for play balance and simplification). If you don't see the launching ship when it launches you need to spot the missiles themselves with their much smaller SM.

Your space probe-like impactor doesn't have to be much more than some tanks of cold gas for maneuevering/course adjustment, a small computer brain with a small battery and a lot of radar absorptive material. It could have a very low thermal signature.

For reasons such as this I tend to think that large stations in fixed orbits are a feature for settings with very low amounts of major conflict or even terrorism. Without superscicnee thay can be extremely hard to defend.

You could make your "stations" not stationary by giving them a propulsion system and making small random changes in their orbits at relatively frequent but allso random intervals. Doing this for rotating stations does get more complicated.
The further away you launch from, the more time the space station has to discover it before it arrives. Large stations can likely afford to have observing probes scattered throughout the star system in order to avoid blind spots (especially if such attacks is a major concern). So, you would have to launch from very far away indeed, giving an abundance of time for telescopes scanning the sky or probes you fly by to discover you.

Having that much time also means that you can get away with making such random orbit changes very infrequently if that is the solution you go for.
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Old 02-11-2019, 12:24 PM   #57
Fred Brackin
 
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Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

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. Large stations can likely afford to have observing probes scattered throughout the star system in order to avoid blind spots (especially if such attacks is a major concern). So, you would have to launch from very far away indeed, giving an abundance
When entire solar systems are monitored for any possible launches that is a setting that has what I was calling a very low level of major conflict (or even terrorism.

You are also probably understimating the difficulty of spotting one of these stealth impactors. It doesn't need to be big and it will have an extremely low thermal signature.
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Old 02-11-2019, 01:17 PM   #58
AlexanderHowl
 
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Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

Accelerating an impactor is usually going to result in massive heat signatures that could be detected by a network of satellites in L4 and L5. Cold gas systems only can provide a few hundred meters per second of delta-v before they become unmanageable (cold gas systems give 1/3 the delta-v of chemical rockets, so they would give 0.05 mps per fuel tank, meaning that 1 mps of delta-v would require 16 fuel tanks). In a realistic setting, accelerating an impactor would require fusion or nuclear pulse engines, both of which cannot be hidden with realistic stealth, and the enemy will know it is coming weeks or months before it get there (though stealth can make it harder to target when it gets near its target).

For example, a TL10 nuclear pulse drive gives 0.005g for 100 mps per fuel tank. A SM+4 impactor could potentially have 15 fuel tanks, allowing it to reach 2,700 mps, meaning that it will have quite a bit of energy. At 100,000 miles, it would do its final corrections, giving the defenders one final chance to stop it. If it is not stopped, it will have the equivalent energy of five megatons of TNT, but there are easier ways to blow things up at TL10.
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Old 02-11-2019, 02:37 PM   #59
Fred Brackin
 
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Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

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In a realistic setting, accelerating an impactor would require fusion or nuclear pulse engines, .
Are you claiming that we don't live in a "realistic setting"? We've sent space probes into the outer ststem and even out of it with chemical engines.
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Old 02-11-2019, 05:07 PM   #60
AlexanderHowl
 
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Default Re: [Spaceships] How does large-scale space warfare play out (without superscience)?

Do you want an impactor to take over ten years to reach its destination? Chemical rockets are only able to get to Saturn through gravitational assists and Hoffman transfers, which take forever. Considering the orbital radius of an artificial satellite will vary by as much as 0.1% per year in a complex system like Saturn's just due to the gravitational interactions, you may be off by quite a bit when you final get to Saturn if you do not want to risk detection by using additional rockets.

Anyway, an impact going to Saturn through using chemical rockets has to expend 12.5 mps just to account for differences in orbital velocity. Since it is nearly impossible for chemical rockets to get to that delta-v through staging, you need the gravitational assists to gain the required delta-v. At best, it might be able to have another 1 mps of delta-v to allow it to ram at 1 mps.
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