[SS] A few questions about SM and armor scaling

[wellspring]

I'm working on a campaign idea and was playing with the Spaceships system, when I noticed a few things and I was wondering if someone can answer a few questions.

Most armor seems to follow the 1/1.5/2/3/5/7/10 progression, but for very low end armors the rounding on 1.5 seems inconsistent. For streamlined steel hulls, you have NO at SM5, followed by 1/2/3. Which means that 1.5 was either skipped or 1 was rounded down to zero. For stone, it starts with SM7 and goes 1/2/2/3, implying that 1.5 was rounded up. Ice starts at SM8, but progresses like Stone.

Then in Spaceships 7, Wood and Etherwood follow an entirely different progression altogether. Adamant and Skystone scale in a manner similar to steel, while Orichalcum has its own entirely idiosyncratic scaling.

The thing is, for things like Steel, the weird rounding differences seem to have little or no real significance. To the point that I thought they might be typos.

I'm asking because I suspect that a lot of thought went into these values and before I start monkeying with them I was hoping that someone involved in the project or playtest could shed some light onto why they behave the way they do.

(I've a few other questions, but this one will suffice for now.)

[weby]

I was not involved with the project, so can only offer my own thoughts based on what I thought when I saw those same strange things.

I do not think there is any consistent logic as if you look at the SM +4 modules they are allowed to have same DR as SM +5 in some cases and for the same SM SL and USL to have the same DR.

In fact in my own system I use exact DR figures that scale correctly instead of the randomly scaling dDR figures. Thus as example stone armor is: SM4:0.3 SM5: 0.5, SM 6:0.7, SM7:1, SM8:1.5, SM9:2 and so on. All the values are rounded down as normal for D-scale combat, but if fired at by normal scale weapons they provide the dDR value*10. That produces some different values than the RAW, but I like the smoothness of the changed system.

Orichalcum: It actually scales the same speed as others but is basically *2 2/3 the steel DR so it looks funny.

As for wood(and etherwood): They just scale differently. I have no clear thoughts on why they scale half the speed. It is likely meant to somehow represent the fact that something that big built entirely from wood would need a lot of internal reinforcement instead of hull, but as none of the other systems have limitations on the structural strength it really makes no sense to penalize only armor modules.

[wellspring]

Thanks! I still hope I hear from someone involved in development, but this was very helpful, especially your house rule about fractional armor values.

I'm also now having a man-crush for your website. Many useful Spaceships rules, errata, and suggestions. I have one suggestion for your Errata section, and I wish SJGames would update the PDF since it's an easy fix that doesn't require any layout changes. In Pyramid 3/34 Alternate GURPS, page 7, the formula is

Crush depth (in yards) = dDR x 150 / L

But this is a typo, acknowledged by David Pulver. It should be:

Crush depth (in yards) = dDR x 15000 / L (Citation)

I'd actually prefer if it were expressed as

Crush depth (in yards) = dDR x 5000 / L

But have L be the ship's length in yards rather than feet, since that's consistent with the rest of Spaceships, and GURPS in general. It also makes the formula easier to calculate.