Is spaceship armor useless?

[Xplo]

Today I was reading through Spaceships and trying to design a TL9 civilian ship that could defend itself against pirate attacks. And it seems to me that armor is nearly useless; any ship of a given size can easily mount weapons that can defeat any reasonable quantity of armor that ship could carry.

In fact, it's worse than that. The smallest conventional projectile listed - 2cm - does 6dx5 dDam, or about 100 on average, which vastly exceeds the dDR on all but the largest and more ridiculously armored ships. In other words: small fighters can kill nearly anything.

Is there something I'm missing here, or is armor really that useless?

[vicky_molokh]

Armour is indeed very low, but the effect is made worse by just how much damage kinetic weapons do.

[Fred Brackin]

Originally Posted by vicky_molokh

Armour is indeed very low, but the effect is made worse by just how much damage kinetic weapons do.

This is unavoidable given realistic assumptions. Very high velocity missiles (even if small) would destroy even very large ships. evena t abse 1 mile per second you're looking at a regime where solid matter doesn't really stay solid. At 10 miles per second you're looking at solid matter exploding with a force of many times (c. 40x) its' own weight in TNT.

If want to duplicate the battles seen in some fiction you need unrealsitic assumptions and rules because those battles are unrealistic. This means looking for high TLs and most especially the ^ sign and optional/cinematic rules.

[vicky_molokh]

Originally Posted by Fred Brackin

This is unavoidable given realistic assumptions. Very high velocity missiles (even if small) would destroy even very large ships. evena t abse 1 mile per second you're looking at a regime where solid matter doesn't really stay solid. At 10 miles per second you're looking at solid matter exploding with a force of many times (c. 40x) its' own weight in TNT.

I remember hearing that such attacks are defeated by something called 'whipple shield principle'.

Originally Posted by Fred Brackin

If want to duplicate the battles seen in some fiction you need unrealsitic assumptions and rules because those battles are unrealistic. This means looking for high TLs and most especially the ^ sign and optional/cinematic rules.

Well sure, okay, but why do I have to invent systems and modifications from scratch to do it? Why is the TL11^ force shield totally wonderful compared to TL11 armour, but TL^ beams totally pointless compared to TL missiles? (There also isn't much of a serious reason to ever bother with bombs.)

Right now, anything short of an invulnerability field or indestructible armour is worse than having:
1. At least 11% as many missiles in a salvo as the target has PD guns and
2. The willingness to press 'Proximity Detonation'.
(Note: even if we postulated automated gunners that automagically hit with every shot for PD, then same has to apply to missiles.)

[Ulzgoroth]

Originally Posted by vicky_molokh

I remember hearing that such attacks are defeated by something called 'whipple shield principle'.

Well sure, okay, but why do I have to invent systems and modifications from scratch to do it? Why is the TL11^ force shield totally wonderful compared to TL11 armour, but TL^ beams totally pointless compared to TL missiles? (There also isn't much of a serious reason to ever bother with bombs.)

TL^ is not a power level. TL^ beams exist to represent fictional beam weapons that don't act like anything really possible. They are probably mostly not drawn from settings where realistic kinetic-kill missiles are competing with them.

Originally Posted by vicky_molokh

Right now, anything short of an invulnerability field or indestructible armour is worse than having:
1. At least 11% as many missiles in a salvo as the target has PD guns and
2. The willingness to press 'Proximity Detonation'.
(Note: even if we postulated automated gunners that automagically hit with every shot for PD, then same has to apply to missiles.)

Have you forgotten about the rapid and very rapid fire options? A PD gun will almost certainly be VRF.

[vicky_molokh]

Originally Posted by Ulzgoroth

TL^ is not a power level. TL^ beams exist to represent fictional beam weapons that don't act like anything really possible. They are probably mostly not drawn from settings where realistic kinetic-kill missiles are competing with them.

My point is that TLx and TLx^ items don't really compare most of the time. Some of them are outrageously superior to mundane ones. E.g. reactionless drives (with power plants) are in all ways better than any other engine for purposes of achieving orbit.

What would be nice is to have a variation of modules listed in the official PDFs such that picking some subset of them (without as much tweaking as is required now) would allow one to achieve the desired feel. Right now it just takes too much effort to make space-operatic spaceships. (Though I'm semi-ready to restart the discussion of houserules that make it possible.)

Originally Posted by Ulzgoroth

Have you forgotten about the rapid and very rapid fire options? A PD gun will almost certainly be VRF.

Seems like I did. So, more power to the defence. Point taken.

Still, the combat devolves into a contest of saturation.

Hmmm. Crits normally mean that defence isn't possible, though I wonder if that applies to PD too.

[Fred Brackin]

Originally Posted by vicky_molokh

I remember hearing that such attacks are defeated by something called 'whipple shield principle'.

)

Nope Whipple (it's man's name) plating is designed to protect against space dust at only a few km per second. A very thin layer of strong material several cm from the real hull explodes when impacted by a piece of space dust. That few cm is enough to allow the explosion to dissipate before it hits the real hull.

The less your incoming projectile looks like space dust the less well it works. Whipple plating is designed to oppose micrograms of mass with milligrams of shielding. Missiles that weighed a hundred killos woudn't be affected much by Whipple shielding. You'd need a much more massive layer of exterior plating a much greater distance from the hull

It's also ablative and even against schemes that work like shotgun shells of space dust would only be stopped the first time.

[Mirtai]

In my experience, Spaceship armor does have a use. Without armor, anyone with Beam weapons will chew you up.

Beam weapons are very accurate, and they cross the distance between ships at (literally) the speed of light.

For example, I was in a playtest where a fighter with 6 missile launchers fought a larger ship with only point defense lasers. The fighter fired from about 2000 miles out... and the ship with the laser turrets destroyed the fighter in the first 20 seconds of return fire from it's lasers...

Meanwhile, the missiles were still accelerating, and wouldn't arrive for several minutes. While the missiles were smaller targets, the laser turrets had tons of time to blow them all away before they arrived. None of the missiles made it even half way.

Now, if the fighter had been well armored, the point defence lasers couldn't have harmed it, and it could have fired all it's missiles to overwhelm the laser turret's point defence, or closed the distance to give the target less time to defend.

At TL 9, it's actually pretty easy to have enough armor to soak most beam weapon fire... and, as it has been pointed out elsewhere, you can shoot down balistic and missile attacks with your beams. But since you cannot shoot other people's laser beams out of the sky, the only defence vs them is armor... so get some if you want to survive past the first 20 seconds of a fight.

[panton41]

Originally Posted by Xplo

The smallest conventional projectile listed - 2cm - does 6dx5 dDam

Where are you getting this number? I see 3d dDAM as the base damage for 2 cm guns?

Edit: You're looking at 20 cm, the smallest gun is 2 cm.

Edit 2 (my signature isn't far from the truth):

I see that the smallest fighter can mount a 16 cm missile at a minimum or an 8 cm gun not counting making it smaller using rapid fire. Keep in mind, though, that civilian ships probably won't be able to survive serious weapons fire. They'll have minimal armor (one layer per hull location) and possibly even the cheapest they can get (to save on costs) meanwhile warships will carry multiple layers of expensive armor and (in many settings) shields and the simple differences in size driving the numbers upward. Look at the armor rating of a SM+15 ship with multiple layers of an expensive armor.

Personally I've found it hard to justify fighters when you're in a fleet engagement. Unless the fighters are solely tasked with targeting support vessels (cargo and tanker vessels, etc.) they really can't make a dent in heavily armored warships, either with missiles and flying like a bat out of hell before firing them. (With the exception of firing nuclear and antimatter missiles.)

[ericthered]

Realistic spaceships (which is the default assumption) behave much like submarines when it comes to combat, which means a small ship can take out much larger ones.

If you want to change that assumption, change it. Triple the armor and HP. Alternatively, treat each hull section independently, with its own HP.