[Spaceships] Submarines of space

[Ulzgoroth]

I decided to see if there was any way to use GURPS spaceships to build a viable stealth-focused ship without superscience.

It turns out that it is, somewhat. My design has a few slightly non-standard components, but they're straightforward and not really necessary.

Name: JP Holland Interdiction Vessel
TL: 9
dST/dHP: 50
Hnd/SR: -4/5
HT: 12
Move: .001G/37.8mps
LWt: 300 Tons
Load: 8.8 Tons
SM: 7
Occ: 8 ASV
dDR: 3/3/3 (hardened)
Cost: 14.7M

Front
[1] Advanced Metallic Laminate (dDR 3 hardened) + 10 tons ionizable gas
[2-4] Fuel Tank (45 tons ionizable gas)
[5] Control Room (3 control stations, C7 network, level 5 sensors)
[6] Spinal Mount (missile launcher, 32cm)
[core] Habitat (2 bunkrooms)

Middle
[1] Advanced Metallic Laminate (dDR 3 hardened) + 10 tons ionizable gas
[2-3] Fuel Tanks (30 tons ionizable gas)
[4] Solar Array
[5] Solar Array
[6!] Mixed Battery (1 30 MJ laser turret, 4 30 KJ VRF laser turrets, 8 tons supplies)
[core] Spinal Mount

Rear
[1] Advanced Metallic Laminate (dDR 3 hardened) + 10 tons ionizable gas
[2-3] Fuel Tank (30 tons ionizable gas)
[4] Spinal Mount (15 missiles)
[5!] Ion Drive (.0005G)
[6!] Ion Drive (.0005G)

Features: Stealth

Crew: 1-8
One pilot officer/captain, one missileteer, one engineer, and extra crew member suggested. Up to four additional gunners may be carried, and the ship can conduct all normal mission activities with only a single crewman.

Supplies: 24.3K fuel load, 15M in missiles usually with 750-1500K worth of nuclear warheads, up to 8K in food


A standard deployment for a JP Holland entails either a somewhat fast pass pre-arranged to intercept one or more regularly scheduled cargo transports, or loitering close to major trade corridors/transfer orbits. Its main mission is to destroy solitary freighters and remain undetected.

The solar arrays are designed to fold when not in use, though they do not retract and remain exposed targets.

Ships are usually named after historic submarines or classes, preferably pre-20th century designs.

Design notes:
The mixed battery is a straightforward derivative of the medium and tertiary batteries. The heavy gun is probably useless in most situations, but it's included in the spirit and role of a U-boat deck gun. The armor/tank combo is 1/3 of an armor section and 2/3 of a fuel tank, which seemed the most elegant way to keep the ship from being completely naked. Taking off the armor probably wouldn't do the design much harm.

If this ship is state-of-the-art (or at least has current-TL stealth), its modifier to be spotted in open space while running the drive is only 46+SM-TL (of the detecting ship), plus search time and +2 for enhanced arrays. This goes down to 42+SM-TL if the ship shuts down and shrouds the solar panels to eliminate their IR signature and run 'silent'. Either way, the ship has a reasonable to very good chance of getting to launch range (.5-1 LS, -48 to -50) of a typical freighter (skill 10-12, basic array) with SM <= TL without being detected, unless the crew is standing intensive sensor watches.

If surprise is achieved a surprise launch should destroy or completely disable the target. This should have a 25kT warhead in most cases, though disabling shots with conventional missiles will usually work if blueprints are available.

After an attack, the Holland can clear datum by a light-second in 69 hours for 1.5mps. This isn't necessarily enough to avoid spotting, but it has a chance depending on what drives are available for pursuit and how close they start.

For best results on long missions, a Holland should be deployed and recovered by a tug of some kind. Saving half the total insertion/extraction delta-V helps keep mission times within semi-tolerable ranges.