Re: [Spaceships] Armor Density
 

Er...that may make something coherent, but only makes any sense once you completely discard the meaning of Systems in the Spaceships mechanics.

Re: [Spaceships] Armor Density
 

"Hits" on armor was kinda dodgy to begin with, ignoring it is a really good idea. Armor is something you penetrate in order to get to the important bits inside, only something like a matter disintigration beam should have any effect on armor - other then going through it or being stopped by it.

Re: [Spaceships] Armor Density
 

I think the volume of what is inside the armour is more important than the volume of armour - armour volume is just how thick the covering will be.

Using excel and VDS:
for a known dDR, you can get the thickness (2.75 pe mm for steel?)
for the weight of armour, you have a volume (density 7.9)
volume and thickness give you area of coverage, ie the surface area these ships are meant to have.
Assign volumes for all systems, and a hull design, and you get how far your armour has to spread.

Re: [Spaceships] Armor Density
 

I was working on a mass/shape modification for spaceships although I got sidetracked and haven't finished it.

Basically, I assigned a density modifier to various components based on the intitial Mass:SM ratio, which hovered around 0.3 Specific gravity... I then just used the Spaceships 3-10-30-100 mass progression to create a "Density Modifier".

• This worked out to -2 for Hydrogen tanks (Specific gravity less than 0.1)

• -1 for open areas and roomy habitats (Specific Gravity less than 0.3)

• +0 for normal habitats, organic/ice armors, and most components (Specific gravity less than 1)

• +1 for low-access components (penalty to Fire Control), Most fuel Tanks and low-density armors (specific gravity less than 3)

• +2 for clamps and high-density armors (Specific gravity less than 10)

• I do have a hardened High-Density Armor type (Irridum based alloy) in my
  campaign that earned a +3 density mofifier (Specific gravity less than 30)

Total it up, divide by 20, round towards zero, subtract it from SM.
This affects targeting and active sensors (not passive sensors).
It also affects armor value, add the density modifier to SM to determine dDR.

------------

I also came up with rules that modified front/center/rear profiles based on shape... as well as coolant issues based on shape. For instance a sphere gets -2 on all profiles but has a much bigger heat problem. The base-line assumption was a 3:1 rectangular/cylindical shape.

Hope that helps!

Re: [Spaceships] Armor Density
 

Nice one. Takes a lot of the maths out - very GURPSian.
Must try it for the designs I have.

Re: [Spaceships] Armor Density
 

As Anthony said, by not assigning armor to the damage system (as it should be). The damage system is based on the assumption that all systems have the same volume. If you use the assumption that armor takes up no volume (which is what this alternative system is based upon), then there's no problem.

Re: [Spaceships] Armor Density
 

Emphasis mine.

No, that's just not true. I've already quoted, from the book, where it specifically states that the systems do not take volume into account. The damage system only takes mass into account not volume.

If your new system doesn't take mass into account and only works on volume, then you'll be fine, but don't go saying that the original system takes volume into account when the book specifically states it does not.

There's no reason you couldn't build one based on Volume, however, you'd have to go back and figure out how large each system is, then rebuild the entire system by adding a mass component to keep track of, and you'd still be limited to 20 systems as each one would then be 5% of the total volume.

Re: [Spaceships] Armor Density
 

The damage system assumes equal hit probability on all components. That only makes sense if all components have equal volume (actually, equal exposed area). Basically, your quote, while accurate, is not true -- the actual behavior of Spaceships is inconsistent with the stated design.

Re: [Spaceships] Armor Density
 

So, what you're saying here is accurate...but the entire point of the design system is simplicity and fun, fast play.

It's explicitly said, and all performance is calculated, based on the assumption of 20 equal-mass slices.

The targeting probabilities is a side effect of wanting to use d6 dice mechanics, and was clearly done for ease of rules and play.

It's a mass-based system, with some kludges there for purposes of fun.

Re: [Spaceships] Armor Density
 

All performance and stats are calculated based on the assumption of 20 slices that are equal in both mass and volume. This is a simplifying assumption, but it results in significant implausible results in extreme cases. There are no ways to fix the anomalies without increasing complexity, but adding extra armor boxes that don't count against the limit of 20 is probably easier than recalculating DR and SM based on what modules the ship contains.