Spaceships - Smaller systems

[Ethics Gradient]

According to the rules in place of a normal sized system I can take 3 one SM smaller systems. Or 9 two SM smaller system, and so on. Which is great because I need more than 20 systems for my ship.

But here's my problem: my ship is SM+7 and each habitat (price 300k) gives me 2 cabins of space. If I instead take 3 SM+6 habitats (each 100k with one cabin) I get 3 cabins of space! This works for larger ships too - a SM+8 habitat gives 6 cabins, but 9 SM+6 habitats give 9 cabins. And all for the same cost.

Is this legal? Some of the ships in Spaceships 8 are using smaller habitats. What am I missing?

[Langy]

SM+6 habitats shouldn't really be rules-legal. A single cabin, on every other ship size, is 7.5 tons. On SM+6 ships, it's 5 tons.

Also, if you use a 2-SM smaller system it provides 10 extra systems, not 9, since the progression is 1-3-10-30, not 1-3-9-27.

[Ulzgoroth]

The rounding in spaceships has painful results all over the place.

[munin]

There are other places where smaller systems produce some weird results due to GURPS Spaceships progressions. If following a rule leads to nonsense results, adjust the rule. Here are some adjustments I like:

For Habitats I would say that spacecraft of SM+7 or higher require 7.5 tons per cabin -- so you can't have an SM+6 Habitat, but you can have a half-size habitat (one cabin occupying half an SM+7 system).

For Open Spaces, a smaller Open Space has 1/3 the areas of a standard-sized system (round down).

SM+10 spacecraft have an additional workspace for every three smaller systems which would require workspaces if standard size (round up).


I also say that smaller Weapons cost 1/3 as much as a standard-sized Weapon system, but that's just because I don't like the cost progression of Weapon systems.

[Ethics Gradient]

Originally Posted by munin

For Habitats I would say that spacecraft of SM+7 or higher require 7.5 tons per cabin -- so you can't have an SM+6 Habitat, but you can have a half-size habitat (one cabin occupying half an SM+7 system).

Sounds good. Shame really, I could have used that extra cabin in a central radiation shielded location.

BTW, can I have a half-size engine with one half acceleration? There are half-size fuel tanks, but no half-size engines are mentioned.

[munin]

Originally Posted by Ethics Gradient

BTW, can I have a half-size engine with one half acceleration? There are half-size fuel tanks, but no half-size engines are mentioned.

I don't see why not. I've used one in a build.

[RyanW]

Originally Posted by Ethics Gradient

Sounds good. Shame really, I could have used that extra cabin in a central radiation shielded location.

BTW, can I have a half-size engine with one half acceleration? There are half-size fuel tanks, but no half-size engines are mentioned.

Don't see a reason not to allow it.

[MatthewVilter]

Originally Posted by Langy

...if you use a 2-SM smaller system it provides 10 extra systems, not 9, since the progression is 1-3-10-30, not 1-3-9-27.

This sounds right to me... I don't need rules to back up this common sense call, but if it is written down somewhere can someone point me to it?

[Ulzgoroth]

Originally Posted by MatthewVilter

This sounds right to me... I don't need rules to back up this common sense call, but if it is written down somewhere can someone point me to it?

No, the written rules don't cover it. The written rules leave out lots of fairly obvious and useful possibilities, and hamstring some others for no good reason.

At least the small clamp, small factory, and large shield generator rules are good for something. (The small control room too, but that was already established by the SS1 authors notes.)

[MatthewVilter]

Okay good to know. Is there like, a list of useful possibilities that get hamstringed for no good reason I could see? ^.^