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Old 09-08-2015, 12:19 AM   #44
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Join Date: Dec 2006
Location: Eindhoven, the Netherlands
Default Re: GURPS Starships line errata (and some observations)

Originally Posted by ericbsmith View Post
Missile and Gun damage is multiplied by relative velocity in miles per second (mps); so the faster the missile is traveling the more damage it's going to do. See p. SS1:61.
Yes, I knew this. I'm talking about something else.

A standard missile has a minimum velocity of 1 to 2. We'll use 2. This means it doubles its basic damage, which is nice. It's ability to hit, though, is a combination of its relative speed and its accuracy. A TL 9 missile is accuracy +1 or +2, and because of its speed, -3 to hit. Thus, you're at -1 or -2 to hit. For the purposes of point defense, a laser is at -0 to hit your missile (based on speed alone).

A super missile " with 100G+ accelerations may optionally
be available (usually if similar accelerations are standard for
" A TL 9 super-missile is psuedo-velocity. By default, you treat base velocity, for purposes of damage, as x10. That's pretty great! But the accuracy remains +1 to +2, and the speed changes your ability to hit to -12, so your ability to hit is -10 or -11. And lasers are at... -0 to hit your missile (based on speed alone). So your speed has removed accuracy and gained nothing in terms of evading point defense. Fortunately, it does increase the damage substantially compared to the standard missile, as you point out.


Damage is not based on the speed of the weapon alone. That's the minimum velocity. Super missiles suggest that they should exist if similar acceleration exists for space craft. The idea is, of course, that your missiles need to be able to hit the enemy ship! A missile travelling at 1-2 mps is never going to be quick enough to hit a ship racing around at 50-100gs! So what does a ship racing around at 50-100gs mean? It means you should be on the Standard Scale at 20 seconds, or at the distant scale at 1 minute.

The standard scale at 20 seconds has a base relative velocity of 10 mps. The distant scale at 1 minute has a 30 mps base relative velocity. This means that a basic missile fired from a ship does 10x damage (in the first scenario), is still at +1 or +2 for accuracy and is at -6 due to speed, for a total of -5 to -4. A beam weapon point defense is still at -0 to hit you.

So, if you're in a standard scale, 20-second turn scenario, which is considered the standard for something like a super missile, and you have a super missile, you're less likely to hit me and you'll do the same damage as I'll do if I fire a missile back at you.

The real reason to have the super missile is because you shouldn't be able to connect with the super-fast ship with a normal missile, but I don't think the core system really covers that well.
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