Pathfinder class Mobile Jump Gate
rating: 0+x

**By DaltonSpenceDaltonSpence **

With its enhanced scientific sensor array, extensive science staff and independant jump-capable scouting vessel, the Pathfinder-class of mobile Jump Gate Stations is used a forward base for exploration of new starsystems.

Length: 200 yd. (600 ft.) Crew Requirement: 2711
Power Points: +6/-72
Air Performance3: Speed: 100 mph/0.1G Hnd/SR: -3/5 Space Performance: FTL-2/0.1G

Systems Table

Front Hull System
[1-2] Upper Stage - Small (SM+10)4
[3] Armor - Steel (20 dDR)
[4-6!!!] SM+13 Jump Gate (Capacity: 10,000 tons)5


Center Hull System
[1] Armor - Steel (20 dDR)
[2] Control Room (Computer: C8 Comm/Sensor: 10 Stations: 20)
[3] Comm/Sensor Array - Science (Level: 12)
[4] Habitat (600 Cabins)6
[5] Open Space (20 Areas or 1 Acre)7
[6!] Weapon Battery - Tertiary (30 Weapon Mounts)8
[Core!] Factory - Fabricator ($5,000,000/Hr)


Rear Hull System
[1] Armor - Steel (20 dDR)
[2] Hangar Bay (Launch: 500 ton/Min / Cap.: 3,000 Tons)
[3] Cargo Hold (5,000 Tons)
[4-6] Power Plant - Fusion (3x2 Power Points each — 50 yr Fuel)
[Core!!] Stardrive - Super Jump (FTL-2 / 0.1G / 300 dDR)9

Design Switches, Features, & Notes

8 Airlocks (Capacity: 8 persons each)
CAMPAIGN OPTIONS: Reactionless Engine (Drive Field), Stardrive (Drive Field, Rotary Reactionless)
SHIP OPTIONS: Spin Gravity (Maximum 0.5G), High Automation

As a long time fan of Babylon 5 I've always been fascinated by their "Jumpgate" technology, which in GURPS terms most closely resembles a Jump Gate described on page 19 of GURPS Spaceships. The main differences between GURPS and Babylon 5 hyperspace seem to be;

  1. the need to "open a jumppoint" to enter and exit hyperspace,
  2. the ability to loiter at the same relative position to the nearest strong gravity well in normal space without power (subject to gravitic drift), and
  3. the ability to detect other ships and maneuver relative to them and fixed hyperspace landmarks (ie. "jumpgate beacons").

As the above characteristics seemed to make dramatic sense in Babylon 5, I decided to incorporate some of them in my personal hyperspace rule set, with a few variations.

  • Hyperspace Jump Gates (usually called Hypergates) open a "door" to hyperspace 0.5x(square root of total tonnage capacity) yards in diameter. The gate must recharge for 60 minutes between uses and will remain open for two minutes or until a mass exceeding its rated capacity attempts to pass through it (whichever is less). Multiple gate systems in the same ship/station may operate independently at staggered times to allow a smoother traffic flow.
  • The minimum size of a TL9^ vessel that can jump to hyperspace on its own is 10,000 tons (SM+10). This is also the minimum capacity of a stable TL9^ Jump Gate requiring a minimum of one SM+13 system, although this could be installed on an SM+12 vessel as a oversized system (see GURPS Spaceships 7, page 5) requiring three power points.10
  • The base FTL-1 velocity (or "hyperspeed") of a Stardrive (also known as a Hyperjump Engine) in hyperspace is 0.2 parsecs/day. Ships too small to enter/exit hyperspace on their own may do so through a Jump Gate. Other names used for the Stardrive system are Jumpdrive or Hyperdrive depending on whether the ship is or is not Jump capable.
  • For some odd reason, newtonian reaction drives do not work in hyperspace, so Rotary Reactionless Drives (known as "thrusters") are required for hyperspace STL manuvering. Because of this, thrusters are automatically included with Stardrives at no extra cost.
  • Since thrusters cannot be used at the same time as the Stardrive, power can be diverted from one to the other. Ships using neither drive system remain stationary relative to normal space (see item 2 above).
  • Ships at hyperspeed cannot adjust their heading directly, so to make course corrections the ship must disengage the Stardrive, adjust the ship's heading with thrusters, then re-engage the Stardrive on the new heading.

Spacecraft Table

TL Spacecraft dST/HP Hnd/SR HT Move LWt. Load SM Occ dDR Range Cost
9^ Pathfinder-class 300 -3/5 13 0.1G 100,000 8,90011 +12 300ASV 2012 2x $30.23 B
9^ Prospector-class 300 -3/5 13 0.1G 100,000 8,900 +12 300ASV 20 2x $26.43 B
9^ Protector-class 300 -3/5 13 0.1G 100,000 7,40013 +12 300ASV 50 2x $28.09 B


Prospector-class Mobile Jump Gate Mining Platform
This variant is used by mining corporations for temporary operations in systems with limited but significant mineral resources. Replace the Scientific Sensor Array with a Mining system (500 Tons/Hr.) and the Major Science! Lab for a Geology one.
Protector-class Mobile Jump Gate Defense Platform
This variant is often used by mercenary corporations for temporary anti-piracy operations in systems with limited but significant threat potential that do not require a full scale military response. Upgrade the Armor from Steel to Metallic Laminate and replace the Scientific Sensor Array with a Tactical one, the Rear Cargo Hold with a second Hangar bay optimized for a particular model of combat spacecraft and the Major Science! Lab for a Large Ops Center, freeing up 500 tons of steerage cargo space for weapons, frozen troops and other combat equipment.

Adventure Ideas