[Spaceships] How does large-scale space warfare play out (without superscience)?

[Michael Thayne]

I've been thinking about how large-scale space warfare plays out if you use the Spaceships rules. It's honestly sort of weird. In a non-superscience setting focused on Earth (and probably most other star systems) you probably have one planet that's friendliest to human life, which is going to be the focus of the setting. When fighting for control of said planet's orbit, the tactics are simplified quite a bit—no need to weigh the merits of complicated fighter-and-carrier setups. You can just have the fighters (or more likely attack drones). Whoever has the most drones "wins"... sort of. Here's where it gets complicated.

The most important weapons in Spaceships are missiles and point-defense lasers. By default, point-defense lasers can be very good, but not perfect. There's always at least a ~2% chance of failing totally to stop an attack. This is okay if the only things in orbit are your drones and the enemy's drones, but what if you also have spaceports or, god forbid, a space elevator? It's tempting for the weaker side to just throw everything they've got at the enemy's most valuable space assets—not the cheap drones—to make the other side's inevitable "victory" as costly as possible. This can work because the rate of bad point-defense rolls is roughly constant, and targeting the most valuable stuff maximizes the costs of a bad point-defense roll.

If one side is massively outnumbered, the "target the spaceports" strategy can be mitigated by assigning multiple point-defense lasers to every missile attack. But if one side is only slightly outnumbered, it's more of a "mutually assured destruction" situation. At least as far as I can tell. I'd be very interested in hearing strategies to make the destruction more one-sided when your numerical advantage is modest.

Now, in order for space warfare to matter much at all, the main world can't be the only thing in the system that matters. The battle for Earth orbit (or whatever) isn't the end of the story. Controlling Earth orbit lets you deny other people the use of space, but the other side might be able to get revenge by hitting you elsewhere. In the Transhuman Space setting, this is what happened in the Pacific War—China wiped out the Transpacific Socialist Alliance's presence in Earth orbit, but the TSA's long-range AKVs (drones) were able to cause headaches for the Chinese in deep space, and in fact continued to do so after the war ended. Again, the solution is plenty of point-defense lasers, and possibly some kind of convoying. During attempted high-speed intercepts of commercial ships, you have the advantage that relative velocity penalizes ballistic attacks, plus the fact that the attacker may only be able to fire off a limited number of salvos before you're out of range.

Thoughts on this set up? Anything wrong with my logic?

[Ulzgoroth]

Okay, so my 'Spaceships is broken' stuff I didn't think the other thread needed? Here I think it is.

Missiles and point defense work very very differently depending on deeply weird parameters. Specifically, turn duration and number of missile crew.

The key is, missiles are enormously more effective one at a time. A single missile can generate as much as 10 hits, and will almost certainly get at least a few. A volley of missiles resolved as a rapid fire attack rapidly throws that away. A 3 missile volley is literally no better than a lone missile, and a 10-missile volley achieves hardly anything extra. And it costs you vastly more.

If you let either turn time or single gunners operating entire batteries force missiles to be fired in volleys, it's wildly different from if you arrange for each missile to be an independent attack. (Of course, the latter is a resolution problem.)

So, to loop back...Spaceships has some really serious problems if you want to use it this way.



As for the counter-value strike, there's a fix for that, especially if you're using tactical maps at all. A defense in depth (with drones or point defense escorts) lets you put missiles fired into your high-value rear areas pass through the point defense filter repeatedly and get bled dry.

[AlexanderHowl]

I generally prefer long distance lasers to missiles and point defense drones to point defense on capital spacecraft. Since missiles have a maximum delta-v, you can calculate how long it takes them to reach their targets, which could be measured in hours at TL9. Multiple point defense drones can engage missiles within their range, allowing for overlapping defenses, greatly reducing the chance that a missile will penetrate to defenses of the spacecraft.

For example, a SM+12 capital ship can easily carry 900 SM+4 point defense drones for the same space requirement as 60 VRF laser turrets and a fusion reactor. Each drone can easily possess 4 VRF laser turrets, meaning that the spacecraft would have 360,000 shots per turn defending it rather than 6,000 shots per turn defending it. If facing a volley of 6,000 missiles, the spacecraft with drones has a decent chance of surviving, as each drone might eliminate 7 missiles, while the ship with turrets will likely be overwhelmed.

[Rupert]

Well, using smaller systems you can do better than that. If you 'cheat' and use them recursively you can do much better, and compete with drones, though in a more detailed system that tracks surface area that probably wouldn't work.

[Michael Thayne]

Originally Posted by Ulzgoroth

As for the counter-value strike, there's a fix for that, especially if you're using tactical maps at all. A defense in depth (with drones or point defense escorts) lets you put missiles fired into your high-value rear areas pass through the point defense filter repeatedly and get bled dry.

I've thought about that. How well it works might depend on scale. The tactical combat scales that seem to work best for realistic ships seems to be either 3 minutes / 100 miles or 10 minutes / 1,000 miles. In the latter case, missiles will cover about three times as many miles per round, and it's fairly easy for them to zip straight through the "defense in depth" in one round unless the attacker is massively outnumbered, and "the attacker is massively outnumbered" can make things easy for the defender even without clever strategies.

In the former case (3 minutes / 100 miles) I've thought a bit less about because for long-range engagements, there's no way you're actually fitting that on your gaming mat, or even on multiple gaming mats laid end-to-end on a long table. You've actually influenced my thinking on this a lot. In terms of finding ways to range-limit missiles, you've convinced me not to do anything stricter than "must get an active sensor lock before launching missiles". For SM+4 drones with tactical arrays, that limits engagements to 90 hexes (or squares?—squares might work better), which can be done with two game mats laid end-to-end. I guess if you wanted to use the 3/100 scale, you could use two game mats and not have them represent adjacent areas of space, just using them to track movements of a fleet's components relative to each other, while fleet movements relative to each other are tracked with pen and paper?

Okay, so now that you've found a way to make the 3/100 scale work, if your point-defense drones have UV lasers, you can have them move ~1000 miles ahead of the thing you want to protect, and the incoming missile will be forced to spend a round inside the laser's range on the way to the target. But that can be countered with attack drones that boost to very high speeds before releasing their missiles. Not sure what the counter for that tactic is.

I also wonder if part of the upshot of all this is that ultimately all "stations" end up with some kind of drive (fusion pulse? fusion rocket?) to help them get out of the way of very-long-range missile sniping.

[Michael Thayne]

Wait a second the "defense in depth" strategy, even when used with assumptions maximally favorable to it, doesn't solve the 2% miss chance problem AFAICT. It can solve the problem that vs. proximity detonation warheads, sometimes your odds of stopping all 10 sub-munitions is even worse than a 2% miss chance, so you have incentive to fire before the sub-munitions are released (i.e. when the missile is still at least 1 round away from the target in the tactical combat system).

[Michael Thayne]

Originally Posted by AlexanderHowl

For example, a SM+12 capital ship can easily carry 900 SM+4 point defense drones for the same space requirement as 60 VRF laser turrets and a fusion reactor. Each drone can easily possess 4 VRF laser turrets, meaning that the spacecraft would have 360,000 shots per turn defending it rather than 6,000 shots per turn defending it. If facing a volley of 6,000 missiles, the spacecraft with drones has a decent chance of surviving, as each drone might eliminate 7 missiles, while the ship with turrets will likely be overwhelmed.

Because of how the rapid fire rules work, how many shots you have matters less than how many turrets you have. (Similarly missiles matters less than number of salvos.) In this scenario you have 3,600 turrets. Against 3,600 salvos you have a potentially serious problem because of that 2% miss chance. (Partly this is a function of how the point defense and spreading fire rules interact. David has confirmed that the second PD attack in a round is at -2, the third is at -4, etc.)

[AlexanderHowl]

Each gunner program is effectively a different character though, so it is a 2% chance per gunner program. If each program of the drones targets a different missile volley, and multiple drones target the same volley, you will have a much higher chance that someone will succeed. For example, if a volley of 10 missiles is attacked by one turret from four different drones, the cumulative chance of all four gunner programs missing is 1:6,250,000. With 900 drones, you can cover 600 ten missile volleys with 6 gunner programs/turrets each, meaning that the probability that any missile will penetrate is pretty low (mathematically, the chances of one missile penetrating is around 1:2,000,000 on a 20-second scale).

[Michael Thayne]

Originally Posted by AlexanderHowl

Each gunner program is effectively a different character though, so it is a 2% chance per gunner program. If each program of the drones targets a different missile volley, and multiple drones target the same volley, you will have a much higher chance that someone will succeed. For example, if a volley of 10 missiles is attacked by one turret from four different drones, the cumulative chance of all four gunner programs missing is 1:6,250,000. With 900 drones, you can cover 600 ten missile volleys with 6 gunner programs/turrets each, meaning that the probability that any missile will penetrate is pretty low (mathematically, the chances of one missile penetrating is around 1:2,000,000 on a 20-second scale).

Yup! This is where having a numerical advantage so you can assign multiple PD guns to each salvo is helpful. How large the numerical advantage needs to be actually depends on an unanswered rules question I posed a few months ago:

Originally Posted by Michael Thayne

If multiple gunners are possibly going to fire in point-defense against an attack, do they all have to declare before any dice are rolled? Or can gunner #2 wait until seeing if gunner #1 got the job done? This potentially has a big impact on the number of point-defense gunners you need to defend large, valuable targets, where a 2% chance the target gets hit by a nuke is not acceptable.

By the first interpretation, you might want two or more PD lasers for every missile launcher your opponent has. By the second interpretation, having 10% more PD lasers than your opponent has launchers might be fine.

[Ulzgoroth]

I've got to ask, how many missiles per salvo are you envisioning?

Because as you note, it's salvos, not missiles, that give effect. RoF is voluntary. It's stupid in setting, but I'd seriously consider only firing one missile per gunner per turn regardless of turn length or number of available tubes in order to not waste colossal amounts of very expensive ammo.

Originally Posted by Michael Thayne

I've thought about that. How well it works might depend on scale. The tactical combat scales that seem to work best for realistic ships seems to be either 3 minutes / 100 miles or 10 minutes / 1,000 miles. In the latter case, missiles will cover about three times as many miles per round, and it's fairly easy for them to zip straight through the "defense in depth" in one round unless the attacker is massively outnumbered, and "the attacker is massively outnumbered" can make things easy for the defender even without clever strategies.

You realize that this problem is entirely an artifact of the tactical system dropping the wait and attack functionality (and the time granularity of course), right? The missiles are going to 'overfly' the screening craft at point-blank range. There's no simulation justification for not being able to shoot at them while they do - it's just the rules decided not to deal with it.

Perversely, it's possible to beat that problem by counter-firing ballistic weapons (although the timing may be brutally restrictive). This probably isn't effective, since guns are inaccurate and missiles are too costly (unless you use missiles above the minimum allowed size on the attacking side). But it could let you force an attack roll when the missiles are hopping over your weapon platform's location.

EDIT to add: What actually could be viable here is use of nuclear counter-fire. Except that that entirely stops working if you don't use 10-mile hexes, so never mind.

Originally Posted by Michael Thayne

Wait a second the "defense in depth" strategy, even when used with assumptions maximally favorable to it, doesn't solve the 2% miss chance problem AFAICT. It can solve the problem that vs. proximity detonation warheads, sometimes your odds of stopping all 10 sub-munitions is even worse than a 2% miss chance, so you have incentive to fire before the sub-munitions are released (i.e. when the missile is still at least 1 round away from the target in the tactical combat system).

That is a plus that I hadn't been thinking about in this go-around, yeah.

I don't see how it doesn't solve the 2% miss chance, though. Defense in depth means that the missiles get attacked (at least) twice - once by the screen and once by final point defense. The latter only needs to engage the 2% that survived the screen.

Although this does bring up an actual, once again perverse, benefit of large missile salvos. A 900 missile salvo (one tertiary battery in 10 minute time, if it doesn't run out of ammo first) can be stopped by a single point defense gun...but it cannot be stopped by any reasonable amount of screening guns, because those chip away at the 900, not at the hits that arise after the ballistic attack roll. You need 100 screening hits before you even give the missiles -1 to their attack roll!

(Of course, 900 separate single-missile salvos would be even harder to stop, but there's no way the rules permit that from less than 900 tubes.)