[gurps] Survivable Spaceships

[Clinton N. Fell]

Hey Onno,
> 
> I've been wondering about the damage rules, and what they mean for 
> ship design. What do you think about this reasoning?
> 

> 
> * Systems within a section can be hit directly, by a natural roll, or
>   indirectly, as damage cascades from the previous section if that is
>   already destroyed. That is a way to take out "core" -- destroy "6"
>   and target it again.
> 
>   A side effect is that "1" is slightly safer from random rolls than 
>   "6", because "core" soaks up cascade effects. 
> 
>   Another side effect is that similar systems should be separated 
>   within a section to prevent the loss of both. If they are 
>   adjacent, the odds of hitting the upper system doubles if the 
>   lower system is taken out. 

this does appear to be true, however before a ship begins taking damage 
the core systems are better protected by at least one overlaying sytem. So 
system 1 is exposed to fire immediately, while core is much harder to hit 
right away.  Once system 6 has been destroyed however the core is 
essentially exposed.  So to game the rules always put critical systems 
either in the core, or in an early numbered slot.  Late numbered systems 
are more vulnerable in extended fights.

Likewise on distributing critical systems throughout the design and 
separate from each other.  But the cascading damage doesn't seem as bad 
here.  If you front load all the critical components in the first 3 slots 
then the last 3 slots get nonessential items it still means about 50/50 on 
cascading damage rolling rampant through your important systems. Spreading 
critical systems throughout the design does significantly increase the 
robustness of the design - but runs counter to some actual design issues 
(i.e.  is it better to have a single engine room containing 3 powerplants 
with the associated support and safety equipment - or 3 rooms with the 
support and safety equipment each for 1 engine).  For large spaceships 
this is less significant - A space battleship is assumed to be 
compartmentalized with redundant systems, but a space yacht is 
considerably less likely to.



Clint