Spaceship DR and damage

[pawsplay]

I don't own 4e stuff on ships and their weapons. Can someone benchmark me a few ships and weapons? Also, does Tales of the Solar Patrol use a similar scale?

[Stormcrow]

The Basic Set has general rules for vehicles. These rules cover all kinds of situations. If vehicles aren’t going to play a primary role in your game, the rules in the Basic Set are plenty. Tales of the Solar Patrol uses only these rules.

The Spaceships series includes detailed rules for the design and use of all kinds of ships. Use these rules if spaceships are featured heavily in your game and you like the detail. Whereas the Basic Set uses normal scale for DR and other statistics, Spaceships uses decade-scale (including dDR). Page 470 of the Basic Set explains how to convert from normal-scale to decade-scale.

The spaceships in Tales of the Solar Patrol do not convert perfectly to the Spaceships system. The problems include fitting the listed damage for atomic guns to the Spaceships tables and working out the correct acceleration and speed of the Electron Drive (the flight times in Tales of the Solar Patrol do not match those in Spaceships, or any realistic flight times).

Quadrone has attempted a conversion. I have been looking at this recently myself, and I can see some room for improvement.

[pawsplay]

I don't need rules, exactly. I want to know approximately how much damage a ship's laser cannon does, and what it would take to penetrate a small ship's DR. The basic set has a couple of star ships with DR 100, which seems almost nonsensical.

[vicky_molokh]

Originally Posted by pawsplay

I don't need rules, exactly. I want to know approximately how much damage a ship's laser cannon does, and what it would take to penetrate a small ship's DR. The basic set has a couple of star ships with DR 100, which seems almost nonsensical.

Assuming an SM+5 spaceship, you get 20 dHP (200 HP) for the ship, and about 5 dDR (50 DR) per extra 5% of mass dedicated to armor (on one of the three sides - front, rear, or mid) at TL9 (more at higher TLs or with Force Fields).

Scale HP and DR with SM the same way you scale penalties on the range table, i.e. 5, 7, 10, 15, 20, 30, 50, 70 etc.

[Langy]

How's 100DR 'almost nonsensical'? A tank has roughly 1000DR. There are suits of ultra-tech armor with more than 100DR.

Depending on tech level, a small spaceship - roughly fighter size - might have around 30DR. The bigger they are, the more armor they have. Same with their weapon damage. The laser cannon in Ultra-Tech does around 6dx10 damage and would fit on a heavy fighter sized spaceship.

[pawsplay]

Originally Posted by Langy

How's 100DR 'almost nonsensical'? A tank has roughly 1000DR. There are suits of ultra-tech armor with more than 100DR.

Nonsensically small.

[vicky_molokh]

Originally Posted by pawsplay

Nonsensically small.

I hope you realize that this DR hangs on a metal box that wants to be as light as possible. Spaceships are not as dense as tanks, you know. If they spend 50% of their slots on armor, they won't be very useful.

[pawsplay]

Originally Posted by Molokh

I hope you realize that this DR hangs on a metal box that wants to be as light as possible. Spaceships are not as dense as tanks, you know. If they spend 50% of their slots on armor, they won't be very useful.

I'm just picturing a guy in a DR 150 battlesuit stepping in front of a spaceworthy vessel and saying, "Don't worry, I'll save you!" In any case, it's clearly not a military vessel. What is the DR of something intended for combat? The Basic Rules offer no guidance on that, and Ultra-Tech gives up after tanks. With a DR 700 tank on one hand, and a DR 100 star freighter on the other, I was at a loss for extrapolating what a fighter or small cruiser looks like.

[Stormcrow]

The exact DR will depend heavily on the purpose, size, shape, and tech level of the ship. The armor systems in Spaceships go from TL0 ice armor (DR 10 for a SM+8 ship) all the way to TL12 exotic laminate armor (DR 7000 for an unstreamlined SM+15 ship).

If you're using just the Basic Set, and you're making up your own spaceships, then you can eyeball it. Compare the DR to the strength of the weapons available and ask yourself how what strength hit your ship should be able to sustain without taking damage.

There are no standard spaceships in GURPS, so you're free to make both weapons and armor as strong or weak as you like.

The average Audie Murphy-Class Patrol Ship from Tales of the Solar Patrol has 250 HP, DR 100, its atomic guns do 10d×5(4) burn damage. That's an average of 10 × 3.5 × 5 = 175 points of damage per hit. With an armor divisor of 4, that means that 150 points will get through the armor of a similarly equipped ship per hit. Two average hits on the body (−50 HP left) will leave the ship in serious danger of being disabled (roll HT each turn of stress). (I think I got all that right.) And then there's the Nega-Barrier.

[jacobmuller]

You'd really be better off just buying Spaceships, I mean $9.99? That, combined with the amazing number of designs listed in the Forum, would solve a lot of problems. It's really easy to use and, like everything in GURPS, the system can be altered to fit your personal tastes/ campaign needs.

Some of my personal designs include a 30ton fighter (DR50h), a 700ton merchant (DR60) and a 30,000ton armoured missile cruiser (DR1,400he). The military vessels have hardened, higher tech level armour, damage reduction and anything over DR100 includes EMA. Weapons - a hit on the cruiser, from one of the missiles it carries, would take it to -6xHP. Its beam weapons will do the same to the fighter. The merchant - would be chewed to pieces by even the smallest of the cruisers weapons.

Other folk might not be using hardened armour, EMA, damage reduction, warp pseudo-velocity drives, graviton beams... So my designs are of no functional use to anyone but me. Even if I designed ships using exactly the same options as someone else, we'd have different ships; tomato/ tomáto.