[Spaceships] Armor Density

[RyanW]

So I've been debating whether these two house rules were too complicated, since they require logarithms, cube roots, and all kinds of other nasty things. So I started simplifying the math. It now features only multiplication, addition, and comparing to a chart. It can be done on a $1 calculator, or very quickly on paper.

And what's best of all: the results are perfectly identical.

First of all, some quick terminology: Heavy armor means steel, iron, or orichalcum. Light armor means ice, wood, or etherwood. Medium armor means pretty much all other armors. Roomy systems are those that have substantial empty spaces, such as habitats and hangar bays, while extremely roomy systems are those that are almost entirely empty space, such as open spaces. If using the smaller subsystems rule, treat a smaller system as 1/3 or 1/2 of a system.

Get the secret number by adding 9 times the number of heavy armor systems and 7 times the number of medium armor systems, then subtract 10 times the number of roomy systems and 30 times the number of extremely roomy systems. Remember this number: You'll need it later.

A lot of armor makes a ship smaller, increasing armor thickness

Look up the secret number on the chart below. If it falls between two rows, use the row above. The result is the multiplier to all dDR (including that of light armor, even though it doesn't contribute to the secret number).

Number	Multiplier
-600	0.6
-554.67	0.7
-287.67	0.8
-131.67	0.9
-34.67	1.0
28.66	1.1
72	1.2
102.5	1.3
124.66	1.4
141.33	1.5
153.66	1.6
163.33	1.7
171	1.8
177	1.9
182	2
185.66	2.1
189+	2.2

A lot of armor makes a ship smaller, decreasing target area

As before, look up the secret number on the table below, using the row above if you fall between. The result is the reduction of SM for combat purposes.

Result	SM Change
-600	+1
-163.33	0
92	-1
172.66+	-2

Special case: Exotic materials

Exotic laminate can be any of a number of different hypothetical ways of making super tough materials. Depending on the exact technology in the setting, this could be a light, medium, or heavy armor, or an even more dense super-heavy armor. If the latter, multiply the number of subsystems by some higher number when calculating the secret number. 9.5 would be as dense as lead, 10 would be as dense as gold or osmium, and 10.5 is exotic collapsed matter of effectively infinite density.

[jacobmuller]

I thought about doing the volume thing. Gave everything a volume rating and compared bulk cargo ships to 70% armour combat ship. Decided it wasn't worth all the extra work - they still fitted into their SM class:( It did, however, give data for floorplans.
Hadn't thought about increasing armour. Guess it'd work in reverse too for high-volume systems (habitat).
re table. Using only dense armour, 20x9 = 180. Any reason it goes over 180?

[Anthony]

An even easier method: just have armor not take up any component space at all (i.e. you can have 20 modules, plus armor); instead, if you have more than 20 total modules in a ship, multiply acceleration, delta-V, and jump capability by 20/(# of modules).

[Darekun]

Part of the problem with any system that adds volume detail to Spaceships is that the systems already have vastly different volumes.

When I first got Spaceships, I tried it out with a handful of designs; among them were a fire support drone and a diplomatic shuttle, both with the same mass(same Spaceships SM). I then tried comparing those Spaceships designs to equivalent VE designs, and they differed in volume by more than an order of magnitude(with corresponding difference in SM).

Which totally makes sense, but it's all ignored by Spaceships. And I do mean ignored, not just abstracted — rolls to hit that drone and shuttle take the same SM modifier, despite the shuttle being a larger target.



Now, a system/list for assigning densities to systems, and a system for adjusting SM based on density, might be neat, and would support this sort of thing. It just has to first determine that 5 tons of armor is thinner on the shuttle than on the drone.

[PK]

Originally Posted by Anthony

An even easier method: just have armor not take up any component space at all (i.e. you can have 20 modules, plus armor); instead, if you have more than 20 total modules in a ship, multiply acceleration, delta-V, and jump capability by 20/(# of modules).

That doesn't make sense, as modules are based on mass, not volume. Armor definitely takes up mass. Using your suggestion, cargo bays would be free, not armor.

[RyanW]

Originally Posted by jacobmuller

re table. Using only dense armour, 20x9 = 180. Any reason it goes over 180?

If you have an exotic armor that is denser than steel, you can use a higher multiplier than 9. Look at the special case note at the end.

[jacobmuller]

Oops - Reading failure LOL

Have you assigned density to other systems?
eg Habitat, hanger, cargo 0.25, electronics 0.5, powerplant 1, drives, 2...

[Mark Skarr]

Originally Posted by Rev. Pee Kitty

That doesn't make sense, as modules are based on mass, not volume. Armor definitely takes up mass. Using your suggestion, cargo bays would be free, not armor.

As would, ahem, empty space. Also hangars and habitats would probably take up significantly less than one module as they're mostly "empty space."

[Anthony]

Originally Posted by Rev. Pee Kitty

That doesn't make sense, as modules are based on mass, not volume.

Modules are based on both mass and volume -- the reason you can only fit X modules in a SM +Y hull is because of volume, not mass. The mass of the modules is handled by the change in performance.

[RyanW]

Originally Posted by jacobmuller

Have you assigned density to other systems?
eg Habitat, hanger, cargo 0.25, electronics 0.5, powerplant 1, drives, 2...

No. I considered it, and might do it in the future. If I do, it's going to be only one or two non-standard multipliers. Maybe -5 for "roomy" systems and -10 for open spaces. That would mean sending the tables into the negative.