Steve Jackson Games Forums - Pre-made spaceships?

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Re: Pre-made spaceships?

Quote:

Originally Posted by thtraveller

For short duration fighters/craft you could go with non-superscience High-thrust Antimatter Thermal Rockets and the fuel is way cheaper. Antimatter catalyzed hydrogen is only $20K/ton rather than 12M$/ton for full antimatter engines.

Their DV per tank is not very impressive, however. In fact, if you're down at that level HEDM chemical rockets might be a better bet. The drives are cheaper, the fuel is much cheaper, and they give good acceleration.

Here's my attempt at a thrown together TL10, nosuperscience fighter:

SM+5 (30 tons)

Front:
[1-2] Armour, Nanocomposite (dDR14), Hardened
[3] Defensive ECM
[4-5] Fuel Tank - HEDM
[6]Weapon, Spinal Mount
[Core] Control Room (Pilot)

Centre:
[1] Armour, Nanocomposite (dDR7), Hardened
[2] Defensive ECM
[3-6] Fuel Tank - HEDM
[Core]Weapon, Spinal Mount: launcher, 24cm, 7 rounds

Rear:
[1] Armour, Nanocomposite (dDR7), Hardened
[2] Weapon, Spinal Mount
[3] Defensive ECM
[4-5] Fuel Tank - HEDM
[6]Reaction Engine, HEDM Rocket

She'll do 2Gs, has 4.8 mps DV (which is actually less than 7 minutes fuel). The price is $2.76M, a full load of fuel is $63K, and the missiles are $2.333M for conventional ones. The missiles are large enough that even cruiser (SM+10 or SM+11, IMO) armour should be vulnerable to conventional warheads.

More DV can be gained by replacing the spinal launcher with a large one and using the space for fuel tanks giving 7 mps DV (and such a design, were it streamlined, could reach orbit from Earth's surface), maybe a large beam weapon plus power plant and only 6.3 mps fuel, or maybe a second engine for 4G acceleration.

Anyway, what we have is a small, high acceleration fighter, with a single large missile system with enough DV for work in orbital space or similar. If more DV is desired acceleration will drop significantly and/or other systems will have to go (and ECM and armour are really the only dispensable systems), or a bigger vessel will be required.

Re: Pre-made spaceships?

Quote:

Originally Posted by Agemegos

You've got no weapon with a rear firing arc to defend yourself against missiles up the chute. Move the medium battery into the centre section and put it in turrets. And my advice would be to replace it with a tertiary battery of very-rapid-fire [improved] lasers so that you can't be swamped.

Small vessels can't have tertiary batteries. Here's a handy table:

Code:

Battery    Minimum SM

Spinal     +5

Large      +5

Medium     +5

Secondary  +6

Tertiary   +7

Re: Pre-made spaceships?

Quote:

Originally Posted by Rupert

Small vessels can't have tertiary batteries.

I see: not listed on the weapons tables. What a pest!

Re: Pre-made spaceships?

We were posting designes in this thread a while back. You might look there for some pre-made ships.

Re: Pre-made spaceships?

Quote:

Originally Posted by Agemegos

I see: not listed on the weapons tables. What a pest!

Well, they are starting to get into the 'too small' range - even a medium VRF laser for a SM+5 ship is only 30kJ, and does 1d-2 damage, which is about 6d in the normal damage scale - it's in the same damage class as a small arm.

Re: Pre-made spaceships?

Quote:

Originally Posted by Rupert

Give back my loophole!

Re: Pre-made spaceships?

What? Three gatling lasers firing 600 shots a minute each a ships the size of a modern fighter not good enough for you? Even though you can have multiple such mounts? Grizzle guts. ;)

Re: Pre-made spaceships?

Quote:

Originally Posted by yffub

I use TL11 Fusion Torches. I suppose it's cheating to use TL11 engines for TL9-10 ships, but they're the only engines that provide the performance that I want. Since it's my campaign, I don't worry about the discrepancy; Torch Drives are considered superscience anyway.

I was thinking the same. The cheap antimatter required for the AM torch would push up the TL too. So TL 11^ Fusion Torch gives a similar interplanetary performance, and you can use HT and/or Water drives for short duration or combat craft.

You can probably avoid superscience drives for non-interplanetary work if you want to, but it does require a bit more initial design effort for those.

Water and Hydrogen based drives allow the PCs to wilderness refuel too.

Re: Pre-made spaceships?

Quote:

Originally Posted by yffub

It is not cheating to create a game world in which STL drives are 1 or 2 TLs advanced, relative to other technology in the setting.

Re: Pre-made spaceships?

What about this "super fighter"? It has hardened armor and three weapon batteries: a fixed-mount launcher and three fixed-mount improved lasers in the front, and a turret with an improved rapid fire laser in the central hull for point defense. It hosts two crewmen: a pilot and a gunner. The launcher is the main "sinking" weapon against big ships, while the lasers are used against other fighters and/or when missiles run out. Generally, the pilot fires the missiles (usually in proximity detonation mode, so that the +4 to hit offsets the -4 for the second task of a different kind) and the gunner is charged with point defense; when missiles run out, the pilot usually fires the three fixed mount lasers.

SM: 6
Front
[1-2] Armor: Nanocomposite
[3!] Weapons: Major Battery
[4!] Weapons: Medium Battery
[5] Defensive Ecm
[core] Control Room
Center
[1-2] Armor: Nanocomposite
[3!] Weapons: Major Battery
[4] Power Plant: Fusion
Rear
[1-2] Armor: Nanocomposite
[3-4] Fuel Tank
[5-6] Reaction Engine: Fusion Torch
Design Options

* Hardened Front Armor
* Hardened Center Armor
* Hardened Rear Armor