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Old 07-11-2019, 09:48 AM   #11
malloyd
 
Join Date: Jun 2006
Default Re: How to make space combat more survivable?

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Originally Posted by Fred Brackin View Post
It's not at all hard to get kinetic energy missiles that will impact with the effect of kiloton nukes. That will happen at the surface layer of the armor anyway but it doesn't save anyone. Unless maybe your spaceships are larger than cities.

Superscience drives that make kk missiles impossible is probably te best place to start.
Probably. The central problem is the energy required to move a mass between planets, at least for trips that are shorter than multiple years, is plenty to vaporize a similar mass of anything at all. You have to keep the energies that propel your ships away from their weapon systems. Not just missiles, but you'd also need to be sure whatever powers engines on that scale can't be used to power beams or other weapons. Technobabble drives that somehow can't be used for energy generation make that easier.

Alternatively you can allow those energies but make the ships out of something stronger than it is physically possible for matter to be - either superscience materials that ignore that fact, or the force fields.
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Old 07-11-2019, 10:07 AM   #12
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Default Re: How to make space combat more survivable?

I, admittedly, haven't read the other threads. I've only done a little space combat, but I have a couple of ideas.

1) There was a scene in The Expanse before a battle where they all got into vac suits and drained all the air from the ship. They did this preemptively knowing that they were going to have hull breaches when they got hit. If this is standard procedure, then to kill the crew you would have to either hit them or target the fuel. Either way, it wouldn't be too hard to disable a ship and board with the majority of the crew still alive.

2) Give a HT check to the ship to avoid catastrophic explosions. Sure, the system is still toast, but surely techniques are possible to mitigate explosions. We use them in modern cars and power plants, so why not in space. Or maybe to redirect the force of the explosion into space? That way, maybe the ship takes on some spin, but doesn't get destroyed. If this is a known in-universe problem, then maybe the engineers in-universe have a solution which boils down to a roll.

3) "We have to eject the warp core before she blows captain!" This is similar to #2. Maybe the solution is to have the explodable parts jettisonable? We see this in Star Trek. When the engine takes enough damage or comes down with plot-osis, it may explode. Fortunately, they built in a handy eject button and can have it safely explode somewhere other than in the ship with all the people.

4) OSHA regulations. Maybe the explodium which powers the ship may not be stored near the people to begin with. Take a look at how the Enterprise is laid out. Maybe in your universe, the engines have to be separated like those warp nacelles are from the rest of the ship. In star trek, there are other reasons, but if those are the exploding parts and the people are a distance away, maybe they don't get blown up. Yes, it makes the ship less fortified, but also more survivable. It may be a sensible way to build.
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Old 07-11-2019, 10:26 AM   #13
malloyd
 
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Default Re: How to make space combat more survivable?

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If this is standard procedure, then to kill the crew you would have to either hit them or target the fuel. Either way, it wouldn't be too hard to disable a ship and board with the majority of the crew still alive.
This isn't actually the problem. Despite how often it happens in science fiction, the problem isn't realistically that something on the ship blows up. It's that the damage done by the weapon is already enough to vaporize the ship, or a chunk of anything else of a similar size. The fuel can't blow up if it's already been turned into plasma by the collision....
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Old 07-11-2019, 10:36 AM   #14
Fred Brackin
 
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Default Re: How to make space combat more survivable?

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Originally Posted by khorboth View Post
I, admittedly, haven't read the other threads. I've only done a little space combat, but I have a couple of ideas.

1) There was a scene in The Expanse before a battle where they all got into vac suits and drained all the air from the ship.

2) Give a HT check to the ship to avoid catastrophic explosions.
1) is actually of debatable value. Without air to slow it down shrapnel from impact sites flies at over a thousand feet per second and doesn't slow down. You'd need to have crew in space armor from UT at a minimum jsut to withstand those sorts of fragments but the space armor sees lower levels of threats if there's still atmosphere. Atmosphere also severely limits plasmas. Atmosphere's chief function besides breathing though is heat re-distibution. With no air al the equipennt inside needs hard-plumbed cooling systems in the walls and the crew need to be hooked into those too. The threat of atmosphere providing a way for concussive blast waves to travel can be dealt with more easily by pressure relief valves. Put your crews in armored space suits sure but don't bother draining off the atmosphere.

2) Just like it isn't vacuum that kills crews it's not exploding engines or whatever either. In Spaceships what kills ships is running all the way through their HP. PCs already get rolls to survive this too.

You can't add "compartmentalization" either because Spaceships is already built around this as a central principle. That's what the 20 hit locations are. Each is a separate compartment in the ship. you transfer damage from the intial hit location because there's enough damage to destroy that compartment and blow through the bulkheads.
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Old 07-11-2019, 11:14 AM   #15
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Default Re: How to make space combat more survivable?

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Originally Posted by Fred Brackin View Post
You can't add "compartmentalization" either because Spaceships is already built around this as a central principle. That's what the 20 hit locations are. Each is a separate compartment in the ship. you transfer damage from the intial hit location because there's enough damage to destroy that compartment and blow through the bulkheads.
It seems like the default assumption is bulkheads meant to shield. What about compartments meant to break? Things which don't transfer damage from one component to the other because they just separate? This forces the opponent to target the people-part of the ship or the drive-part of the ship or the small fragile connector bit. I don't think it's supported by the rules, but it doesn't seem unreasonable.
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Old 07-11-2019, 02:22 PM   #16
Fred Brackin
 
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Default Re: How to make space combat more survivable?

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It seems like the default assumption is bulkheads meant to shield. What about compartments meant to break? Things which don't transfer damage from one component to the other because they just separate? This forces the opponent to target the people-part of the ship or the drive-part of the ship or the small fragile connector bit. I don't think it's supported by the rules, but it doesn't seem unreasonable.
This would be the thing known to CT as a "dispersed structure" probably. There were no favorable rules there except perhaps for cheapness (and maybe meson guns). You couldn't armor such a hull in CT and I think it would be much more expensive in Gurps.

It wouldn't help at all with the secondary explosions from nuke-scale kinetic impactors and not real nukes either. What it might do is expose the systems that are (Core) in Spacships so they could be attacked directly.

It would also make radiation shielding much harder.

You wouldn't try and defend against nuclear scale explosions by spreading out your components by a few tens of meters. You'd make smaller whole ships and spread them out by hundreds of kilometers.

I've been trying to convey that the way to make Spaceships combat more survivable is to change the weapons used. Fiddling with ship designs won't do much at all.
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Old 07-11-2019, 02:38 PM   #17
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Default Re: How to make space combat more survivable?

High velocity impactors aren't really nuke-like, even if they have as much energy. (Which is highly unlikely unless you've given your KK weapon superscience propulsion.)

A meteoric-speed impactor is only going to transform into an omnidirectional explosion if it gets stopped by what it hits. If it doesn't lose most of its multi-mps incoming speed in the collision, it mostly blows through the hull in a cone of plasma and shrapnel. Only a small fraction of the energy winds up in material flung off perpendicular to the original impactor's trajectory.
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Old 07-11-2019, 03:12 PM   #18
Anthony
 
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Default Re: How to make space combat more survivable?

I strongly recommend use of an exotic drive tech that simply makes kinetic missiles less effective. It can be particularly useful if drives generate a warp field of some sort, because then you can tune its properties for whatever else you want to go on, such as boarding actions (two examples of this are Drive Field in Spaceships 31, and Exophase Drives per SS7:22, but plenty of other options exist). A lot of SF is best handled as a Hyperdynamic Cosmos (SS7:26).

Another thing to consider is not having space combat. Even when survivable, it's generally pretty boring.
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Old 07-11-2019, 03:34 PM   #19
Fred Brackin
 
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Default Re: How to make space combat more survivable?

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A meteoric-speed impactor is only going to transform into an omnidirectional explosion if it gets stopped by what it hits. .
That's what's going to happen. Objects only remain solid when molecular binding energy exceeds the kinetic energy of the component particles. That only happens at sub-meteoric speeds.

Even at 7 miles per second a mass contains enogh energy to explode like 20 x its' own weight of TNT. The non^ missiles of Spaceships have 10 miles per second of Delta-V at 28 cm or less and 20 at 32 cm or larger.

So that 32 cm missile turns into a plasma 57x as energetic as detonating TNT and that's the entire missile and not just a warhead.

https://en.wikipedia.org/wiki/Table_...ion_velocities

....puts the detonation velocity of TNT at 6900 meters per second. A plasma 57 x as energetic as that must have a velocity of the square root of 57 x 6900. That's 52,000 meters per second which is actually faster than the 32,000 meters per second obtained from the missile's Delta-V.

So there will be no solid pieces of the impactor or the part it impacts directly. Just an incredibly energetic plasma. Solid chunks from the edge of the blast zone where the explosion has started to dissipate are possible but they won't be going forward. Al the little individual atomic nuclei have collided with other atoms and transformed their momentum into radiating photons and random motion.
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Old 07-11-2019, 03:51 PM   #20
Anthony
 
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Default Re: How to make space combat more survivable?

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Originally Posted by Ulzgoroth View Post
A meteoric-speed impactor is only going to transform into an omnidirectional explosion if it gets stopped by what it hits. If it doesn't lose most of its multi-mps incoming speed in the collision, it mostly blows through the hull in a cone of plasma and shrapnel. Only a small fraction of the energy winds up in material flung off perpendicular to the original impactor's trajectory.
This is of somewhat limited relevance. Consider a 100g kinetic impactor at 20 km/s with a cross-section of 1 cm^2 hitting a hull with a sectional density of 10g/cm^2. It has a kinetic energy of 20 MJ. After the impact, the average velocity of the resulting plasma is 18.2 km/s (with total mass 110g) with total kinetic energy 18.2 MJ, and the remaining 1.8 MJ will consumed turning both components into a plasma cloud expanding at 6 km/s.

Now, assume there's air on the other side. Our plasma starts out pretty dense, but it's still going to interact air, spreading further. The end result is that it only takes a few meters before nearly all the energy is converted into a general explosion.
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