[Spaceships] A reevaluation of missiles and point defense

[SuedodeuS]

I just reread the description of hardened from the basic set, and now I see that the lowest it can make an armor divisor is 1. So, yeah, impact warheads are, in fact, useless - at least against military craft.

This changes when force screens come into play. Because I don't see any option for hardening force screens, impact warheads have a better chance of making it through to strike the actual ship. Of course, if the purpose of the attack is to weaken the shields so that a bigger weapon can be brought to bear, I'd say proximity warheads are the way to go.

I don't suspect reactionless drives to change combat too much. Certainly, higher acceleration craft become more affordable (since you don't have to buy antimatter fuel!), but since we've mostly been ignoring price concerns, that doesn't play much of a role. Of course, the decreased storage space for fuel can mean more PD, although I suspect some of the space will need to be used to actually power the reactionless drives.


So far as sub-tertiary mounts are concerned, there certainly is some good justification for allowing them. Because I rather like fighters, however, I'd probably shy away from them. It's kind of hard to justify from a realism perspective. Maybe that many weapons requires such a ridiculous amount of maintenance that it's actually more effective to just limit out at tertiary, or maybe armored warheads are sometimes used.

Of course, I'm not expecting quite the haphazard use of nukes Ulzgoroth indicates. I'd expect them to be used when each one has a high chance of hitting - such as after PD has mostly been destroyed. If I come up with some armored warheads (probably some semi-ablative dDR and 1 HP), all tactical nukes would be of that type.

[jacobmuller]

I was thinking about the sub-tertiary weapons option.
Would a point against sub-tertiary mounts be, perhaps, in putting a limit on how small a weapon you can mount, this is also a limit on a big ship's versatility. This way, if you need to zap smaller ships, you also need to deploy suitable mid-size ships to handle the smaller weapons.
Would a point in favour of sub-tertiary weapons be: how many .50cals does the Iowa have?
I'm in favour of sub-tertiary weapons if said weapons are still of a size listed in the charts, i.e. 3kj beam/ 2cm gun/ 16cm missile, reasoning that anything smaller is really an anti-personnel weapon.

[Dinadon]

Originally Posted by SuedodeuS

Because I don't see any option for hardening force screens

Try looking at force screen varients, on spaceships p.32

[SuedodeuS]

Originally Posted by Dinadon

Try looking at force screen varients, on spaceships p.32

I forgot the force screen variants were in the Design Switches section. Its placement implies that it isn't meant to be a default option for force screens, however. Alright, if the GM allows hardened force screens, impact warheads are yet again useless. Personally, I think the closest thing to a "hardened" force screen should be the heavy screen. Hardened armor makes some sense (composites, reactive armor, etc), but how do you harden a field of energy? The only methods I can really consider seriously are ones that would be more likely to increase DR - which is exactly what the heavy screen does.

[Ulzgoroth]

Hardened means 'resisting armor-penetration enhancements'. Depending on how shields work, they could very well be completely unaffected by things like the frequency of incoming photons, or the shape of a kinetic energy weapon, which would effectively give them cosmic hardening.

Originally Posted by SuedodeuS

Of course, I'm not expecting quite the haphazard use of nukes Ulzgoroth indicates. I'd expect them to be used when each one has a high chance of hitting - such as after PD has mostly been destroyed. If I come up with some armored warheads (probably some semi-ablative dDR and 1 HP), all tactical nukes would be of that type.

If you had a weapon capable of disabling the PD, why would you even bother to switch to nukes? They might make the finishing blow a little bit cheaper, but at that point, however it is you're doing it, you're winning already.

I guess to soften up the PD you'd fire missiles at weak points, which should let you slip some damage in (except perhaps against a SM+15 superheavy, which can actually afford to carry 600 dDR). That could work fairly well if the capital ship is unprotected. It requires your attack squadron to get an advantaged position before engaging, though, since the PD will be centrally mounted. Also requires blueprints of the enemy warship.

Given that the only superscience-free high-thrust maneuver drive with remotely acceptable delta-V is Orion (and the only other TL9 possibility is nuclear salt water), I don't see how you can be shy about scattering a few nukes in an attack. The warheads are cheap, anyway. It's the missiles, fuel, and wrecked ships that'll cost you.

Jacobmuller, if you allow ships to carry 3KJ VRF, it would be completely impossible for missiles to ever do anything. Even an SM+5 fighter could carry tertiary batteries of point defense. There's no way that even guns would get through that. Beams are the only weapon that would work at all, unless you brewed up some custom armored missiles.

Limiting the versatility of big ships is exactly the point of not using sub-tertiary batteries. If that versatility is not limited, there is nothing a small ship or collection of small ships can do, that an equal mass of large ship cannot do better.

[SuedodeuS]

Originally Posted by Ulzgoroth

Hardened means 'resisting armor-penetration enhancements'. Depending on how shields work, they could very well be completely unaffected by things like the frequency of incoming photons, or the shape of a kinetic energy weapon, which would effectively give them cosmic hardening.

I suppose my problem isn't so much with hardened shields existing, it's more of "hardened" option for unhardened shields existing. Of course, since it's superscience anyway, there's no problem saying "they just work that way." I just won't be doing so.

Originally Posted by Ulzgoroth

If you had a weapon capable of disabling the PD, why would you even bother to switch to nukes? They might make the finishing blow a little bit cheaper, but at that point, however it is you're doing it, you're winning already.

At missile range, the fighters are also in range of any fighter-killing weaponry the capital ship possesses. The less time they spend in that range, the better. Thus, they would try to strike hard and fast - hopefully softening up PD - then retreat. Because the nuke-toting gunship still has all its PD (provided someone didn't screw up) and heavy armor, it's nearly immune to the capital ship's fighter (and capital ship) killing armament and is safe to launch the coup de grace.

Originally Posted by Ulzgoroth

I guess to soften up the PD you'd fire missiles at weak points, which should let you slip some damage in (except perhaps against a SM+15 superheavy, which can actually afford to carry 600 dDR). That could work fairly well if the capital ship is unprotected. It requires your attack squadron to get an advantaged position before engaging, though, since the PD will be centrally mounted. Also requires blueprints of the enemy warship.

If you're in an SM+5 fighter and you're going up against an SM+15 superheavy, it's time to reconsider your career choice.
Joking aside, I'd say that is the optimal way for fighters to engage a large target. Unless I'm once again mistaken (track record points to yes), it's possible to fire at weak points if you've made a successful engineering analysis task. A fighter squadron could have a variant with it that performed such tasks and relayed the information. Risky, but it would allow such tactics to be used without a blueprint.

Originally Posted by Ulzgoroth

Given that the only superscience-free high-thrust maneuver drive with remotely acceptable delta-V is Orion (and the only other TL9 possibility is nuclear salt water), I don't see how you can be shy about scattering a few nukes in an attack. The warheads are cheap, anyway. It's the missiles, fuel, and wrecked ships that'll cost you.

You're absolutely right - nukes are cheap. Assuming 16cm missiles weigh 1/10 ton, it only costs half again as much to make one into a nuke (conventional 16cm missiles work out to $100K, while a 25 kiloton nuke is only $150K). As the nukes get bigger, the relative cost actually goes down - still half again for 100 kt, but only 1/4 again for 2.5 Mt and 10 Mt.
It still doesn't sit right with me to use them as though they were missiles, however. I'd probably end up having some sort of nuclear weapons treaty preventing excessive use.

Originally Posted by Ulzgoroth

Jacobmuller, if you allow ships to carry 3KJ VRF, it would be completely impossible for missiles to ever do anything. Even an SM+5 fighter could carry tertiary batteries of point defense. There's no way that even guns would get through that. Beams are the only weapon that would work at all, unless you brewed up some custom armored missiles.

Limiting the versatility of big ships is exactly the point of not using sub-tertiary batteries. If that versatility is not limited, there is nothing a small ship or collection of small ships can do, that an equal mass of large ship cannot do better.

QFT. Subtertiary PD batteries can easily prevent any ballistic attack short of ramming. I wouldn't mind seeing the math of a subtertiary VRF gun battery going up against a subtertiary VRF laser battery, though.
If you want fighters to exist, you'll probably need to keep the smallest battery at tertiary. It's hard to imagine a role for small craft - other than as piloted missiles or recon craft - in large-scale space combat if it's effectively impossible for them the damage capital ships.

[Ulzgoroth]

Originally Posted by SuedodeuS

At missile range, the fighters are also in range of any fighter-killing weaponry the capital ship possesses. The less time they spend in that range, the better. Thus, they would try to strike hard and fast - hopefully softening up PD - then retreat. Because the nuke-toting gunship still has all its PD (provided someone didn't screw up) and heavy armor, it's nearly immune to the capital ship's fighter (and capital ship) killing armament and is safe to launch the coup de grace.

I think you're misjudging the beam-weapon dynamics at L range and out. A VRF beam against SM+5 balances out to zero modifier, and at TL9 that beam has to be a SM+12 medium battery. If it's a fixed mount, it can get a +2 out of that, but ECM can be worth -6, or -3 with tac-sensors, and the gun only does 2d*5/2 per hit, so it works out to fighters not dying all that quickly. And bear in mind that they're attacking something 3000 times their own size in this scenario. Acceptable losses are definitely in play.

A singular larger gunship, on the other hand, is at risk if it comes anywhere near a well-armed capital unit. It's easier to hit, due to its size, unless it's as big as the capital ship being attacked it can be seriously damaged by primary or spinal fixed beams, and it doesn't have the safety in numbers that fighters do. If it's more like an oversized, armored fighter, you probably need something like a 3GJ RF, preferably fixed, which is all-around awkward but possibly worth carrying.

But I'm not sure why you'd use medium gunboats like that. Fighters can deliver the nukes perfectly well on their way out, especially since unless you've totally disarmed the capital ship you still need to shoot a few. Heavy weapons aren't intended for antimissile work, but taking out a 25kT weapon with an capital-ship killing main beam is a good trade in my book.

...I'm going to try to build a heavy warship, and see if I can come up with something at all practical. It's going to be big, I can tell you that.

Originally Posted by SuedodeuS

If you're in an SM+5 fighter and you're going up against an SM+15 superheavy, it's time to reconsider your career choice.
Joking aside, I'd say that is the optimal way for fighters to engage a large target. Unless I'm once again mistaken (track record points to yes), it's possible to fire at weak points if you've made a successful engineering analysis task. A fighter squadron could have a variant with it that performed such tasks and relayed the information. Risky, but it would allow such tactics to be used without a blueprint.

Yes, it can. I thought that was harder than it is, but you only have to succeed by 5+. It's difficult, but should be possible. Send along some fighter-sized sensor shuttles maybe, and have them share the results.

You may be right about that being competitive with or even better than just dropping a bucket of nukes. Depends on the circumstances, I suspect. I've been assuming that there are more than a hundred fighters out there, so they can overwhelm the big ship's integral PD and annihilate it in a single nuclear launch. Given the mass difference, I think that ratio is more than fair to the capital ship.

Oh, and to prod at the joke, with 999 friends and a couple nukes each, that'd be a downright easy fight. Depending on its return fire, we might wind up decimated, but that's a lot better than they'd do.

Originally Posted by SuedodeuS

You're absolutely right - nukes are cheap. Assuming 16cm missiles weigh 1/10 ton, it only costs half again as much to make one into a nuke (conventional 16cm missiles work out to $100K, while a 25 kiloton nuke is only $150K). As the nukes get bigger, the relative cost actually goes down - still half again for 100 kt, but only 1/4 again for 2.5 Mt and 10 Mt.
It still doesn't sit right with me to use them as though they were missiles, however. I'd probably end up having some sort of nuclear weapons treaty preventing excessive use.

You also want these errata here (they ought to be listed in the PDF errata as well, but they aren't). They don't make your basic evaluation wrong though. Nukes are cheap.

I've got no aversion to throwing them around like popcorn, myself, so long as you're doing it away from habitable planets. But if you don't like it, treaties are probably the way to go. Or nuclear dampers. Nukes have a limited but real place in Spaceships combat.

Originally Posted by SuedodeuS

QFT. Subtertiary PD batteries can easily prevent any ballistic attack short of ramming. I wouldn't mind seeing the math of a subtertiary VRF gun battery going up against a subtertiary VRF laser battery, though.

I'd need some definitions. You can already build a 2cm VRF cannon, but you can't make a gun smaller that 30KJ VRF by the book. It's the option of making point defense guns 10x smaller than any other weapons that completely broke the picture. I don't think a 2mm VRF cannon makes any sense, and it'd probably have too little damage to be used as a weapon.

[Ulzgoroth]

Ok, here's my effort to build a capital warship. I am...doubtful of it's utility. Unless somebody else can come up with a much better design, I'm unconvinced that large ships have any place in TL9 combat.


TL: 9
dST/dHP: 500
Hnd/SR: -3/5
HT: 13
Move: 2G/105.6 mps (mostly at .005 G)
LWt: 300,000 Tons
Load: ? Tons
SM: +13
Occ: 500 ASV
dDR: 300h/100h/100h
Cost: 24.6B

Front
[1-3] Advanced Metallic Laminate (dDR 300 hardened)
[4*] Mixed Battery (1x3GJ RF fixed, 6x100MJ VRF fixed, 2x300MJ RF fixed)
[5*] Major Battery (fixed 100GJ laser, 2d*50(2) L/X)
[6] Fuel Tank (15 k ton nuclear pellets)

Middle
[1] Advanced Metallic Laminate (dDR 100 hardened)
[2] Habitat (100 bunk rooms, 50 cabins, sickbay, total life support)
[3*] Mixed Battery (2x100MJ VRF turret, 24x 30MJ VRF turret)
[4-5] Fuel Tank (30 k ton nuclear pellets)
[6] Tactical Array (comm/sensor 13)
[core] Control Room (C8 network, comm/sensor 11, 30 control stations)


Rear
[1] Advanced Metallic Laminate (dDR 100 hardened)
[2-3] Fuel Tank (30k ton bomb pulse units)
[4] Fuel Tank (15k ton nuclear pellets)
[5] Advanced Fusion Pulse (.005G, 20mps/tank)
[6] External Plasma Pulse (2G, 4mps/tank)
[core] Fusion Reactor

Notes:
-Fuel costs: 7.5B tactical fuel, 3B cruise fuel.
-For best effect, the ship's engineer should increase power every round in combat.
-Designed for L range, but can kill much faster at S range.
30MJ: S
100MJ: S/L
3GJ:L

[joelbf]

I've redone my calculations from my first post, but with spread-fire penalties for the pd-gunners.

Worst case (for point defence) is 10-minute scale. Assuming skill 12 (and noting that higher skill gives an edge to point defence):

Effective skill for missiles is 32, which gives on average 22,21 hits with a stdev of 4,15.

Effective skill for pd is 18, this means that spreading fire over 3 targets gives the best total result: 25,4 hits with a standard deviation of 5,26.

This means that on average -3,19 missiles will hit with a stdev of 6,7; the probability of less than one hit is 73%.

If you use 2 pd-turrets per missile launcher the distribution drops to -28,6 hits on average with a standard deviation of 8,52. The probability of less than one hit is 99,97%.