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Babylon 5


Anyone here ever do a write up of B5? The size of the station in tons (!) Starfury's, etc?

I'd be interested in seeing it.


Originally posted by Solo:
Anyone here ever do a write up of B5? The size of the station in tons (!) Starfury's, etc?

I'd be interested in seeing it.


8km long, and about a 10:1 ratio, which would mean it displaced about 287 *million* tons of hydrogen, with a surface area of about 2.111 million square meters.

In 2300AD terms, thats 422,230 hull hits!

B5 was built for 4 squadrons of fighters (one on each of the 4 Cobra arms), started with 2 (Alpha and Epsilon), gained Zeta squadron in "Survivors" and Echo squadron in "Severed Dreams". Squadrons seem to be roughly 6 Furies strong, but several of the command staff have additional furies of their own. Hence in early season episodes they're usually 7 fighters on patrols (6 of the squadrons and Sinclairs). The Omega class definately carried 24 and the Hyperions 6.

So assuming all ships in "Severed Dreams" had full compliments, there were:

Rebel: 18+24+24 = 66 fighters (B5 and 2 Omegas)
Loyalist: 24+24+24+24+6+6+6 = 114 fighters (4 Omegas and 3 Hyperions)

The given length is 9.6m, which, given the boxy configuration and calculations on engine size makes them in the 80-90 dton range (given mass if 48 tons, meaning them have a lot of lightweight materials).

The EF Omega class is over 3 million dTons in size, and has a mass of 44.6 mtons, for a density of 0.89, a little less than water. Must be a lot of space inside.

There was information in the two Bablyon 5 games (the Babylon Project RPG and Babylon 5 Wars). The RPG is out of print. The Babylon 5 Wars game is going to be out of print on the 31st (Agents of Gaming lost the license since Warner Brothers decided that they weren't going to license B5 anymore).

Unfortunately, I don't remember of the information, and I no longer have the games.

Thread Resurrect

Using this fan-produced site:


...plus the sort-of-random assumption that 14 mass tons = 1 displacement ton for armored warships (on the average), then:

G'Quan-class Heavy Cruiser (Narn)
1400m long, 18.6 million metric tons
= 1.3 million tons volume
I'd scale this back and classify it as an early-interstellar dreadnought.

Aurora-class Starfury (Terran)
9.5m long, 48 metric tons
= 3.4 tons volume
No, it has to be larger than that... let's see.
4 wings at appx 5m x 6m x 0.5m = 4 tons total.
Cockpit appx 5m x 5m x 4m = 7 tons.
Total volume is close to 10 tons.
This would be like a souped-up 10+ton Rampart, or more like a larger bomber.

Nova-class Dreadnought (Terran)
1500m long, 32 million metric tons
= 2.2 million tons volume
I'd scale this back and classify it as an early-interstellar dreadnought.

Omega-class Destroyer (Terran)
1700m long, 44 million metric tons
= 3 million tons volume
I'd scale this back and classify it as a TL12-15 dreadnought.

Sharlin-class War Cruiser (Minbari)
1600m long, 44 million metric tons
= 3 million tons volume
I'd scale this back slightly (1 million tons) and classify this as similar in capabilities as a pre-Maghiz Darrian superdreadnought.

Primus-class Battle Cruiser (Centauri)
1500m long, 22 million metric tons
= 1.5 million tons volume
I'd keep the size and classify it as an early-interstellar dreadnought.

Vorchan-class Attack Cruiser (Centauri)
600m long, 3.2 million metric tons
= 230,000 tons volume
I'd classify this as an early-interstellar dreadnought.

Lightning-class Fighter (Vorlon)
25m long, unknown mass
Roughly conical, so say 10 to 20 tons.
This would be an above-Imperial-tech fighter. TL20? Higher?

Star Dreadnought (Vorlon)
1330m long, unknown mass
Probably around 1 million tons volume.
This would be an above-Imperial-tech dreadnought. TL20? Higher?

Planet Killer (Vorlon)
perhaps 45,000m long, unknown mass
Terrifying size.
This would be an above-Imperial-tech monstrosity. TL20? Higher?

"Battle Crab" (Shadows)
1.5km long, unknown mass
Perhaps 1 - 1.5 million tons volume.
This would be an above-Imperial-tech dreadnought. TL20? Higher?

Zephyr 109 Light Fighter (corsair)
16m long, 32 metric tons.
Probably 10 tons. Very light armor.
This would be an early interstellar fighter.

Raider "Battlewagon" (corsair)
300m long, 2.1 million metric tons.
= 150,000 tons volume
Essentially a budget battle rider for up to 21 Zephyrs.
This would be an early interstellar carrier.

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Okay, so noone's taken the bait so far. I can only push this so far on my own...

I'm wondering why these ships are so huge. From a gameplay perspective, you know, not from a "well JMS said so" angle. Justification.

The options I came up with include

(1) They're HEPlaR-driven; they have lots of fuel
(2) Their spinal guns are absolutely HUGE.
(3) Their power plants are absolutely HUGE.
(4) Their pathetic maneuver drives are HUGE.
(5) They carry a lot of support craft.

They're probably all true, with perhaps #1 having exceptions for the advanced races.
So here's some possible things I could come up with.

(1) B5 ships have something like subspace jumpdrives, which require no fuel, but a heckuva lot of power.

(2) From what forum posters seem to say, Earthforce ships run on reaction drives, so perhaps that means something like HEPlaR. The big ships are lumbering beasts, which means the drives are really big compared to Traveller ships -- they remind me a bit of the Discovery's engines from 2001: A Space Odyssey.

(3) So, the big B5 dreadnoughts are mostly powerplant and reaction mass fuel, then spinal gun, with enough room to squeeze in carried craft, the subspace jumpdrive, reaction drive, and life support.

If I assume that Earthforce dreadnoughts carry a couple of 5000t escorts, and the hangar requirement is many times the volume of carried craft for maintenance purposes, then that could also take up plenty of space. Assuming that ships strapped to the hull require no extra volume, but also can't be protected or repaired very well (for some value of "very well").

So, given a million-ton Earthforce dreadnought, maybe I'm looking at:

200,000 t powerplant
200,000 t long-term-storage jump capacitors
200,000 t fuel
150,000 t PA spine
150,000 t hangar
20,000 t subspace jumpdrive
10,000 t reaction drive
20,000 t bridge, staterooms, life support
50,000 t for other stuff

I should be using HGS to help benchmark this. I can fill up 500kt easily with it even using the "little" spinal guns. The other 500kt could be divided up between fuel, capacitors, and carried craft.
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Right, a million ton ship with a PA spine and no screens, using HGS:

Ship: Hyperion
Class: Hyperion
Type: Dreadnought
Architect: JMS
Tech Level: 13

HD-Y3115G4-590007-78R39-3 MCr 645,006.872 1 MTons
Bat Bear 5 Y 5W1YY Crew: 8214
Bat A Z AX1ZZ TL: 13

Cargo: 578.000 Emergency Low: 1000 Fuel: 250,000.000 EP: 50,000.000 Agility: 0 Shipboard Security Detail: 1000 Marines: 1000 Pulse Lasers
Craft: 36 x 20T Fighter, 10 x 2500T Escorts, 3 0T Launch Tubes
Fuel Treatment: Fuel Scoops
Backups: 1 x Model/7fib Computer 1 x Bridge
Substitutions: W = 150 X = 300 Y = 100 Z = 200

Architects Fee: MCr 6,450.069 Cost in Quantity: MCr 516,005.498

Detailed Description

1,000,000.000 tons standard, 14,000,000.000 cubic meters, Cylinder Configuration

581 Officers, 6597 Ratings, 36 Pilots, 1000 Marines

Jump-1, 1G Manuever, Power plant-5, 50,000.000 EP, Agility 0

Bridge, Model/7fib Computer
1 Backup Bridge, 1 Model/7fib Backup Computer

Spinal Mount, 600 100-ton bays, 300 50-ton bays, 950 Hardpoints

Particle Accelerator Spinal Mount (Factor-R), 200 100-ton Meson Bays (Factor-3), 200 100-ton Missile Bays (Factor-9), 300 50-ton Fusion Gun Bays (Factor-8), 450 Single Pulse Laser Turrets organised into 10 Batteries (Factor-7)

200 100-ton Repulsor Bays (Factor-7), 500 Triple Sandcaster Turrets organised into 10 Batteries (Factor-9), Armoured Hull (Factor-5)

36 20.000 ton Fighters (Crew of 1, Cost of MCr 0.000), 10 2,500.000 ton Escortss (Crew of 2, Cost of MCr 0.000), 3 0.000 ton Launch Tubes

250,000.000 Tons Fuel (0 parsecs jump and 28 days endurance, plus 200,000.000 tons of additional fuel)
On Board Fuel Scoops, No Fuel Purification Plant

5,000.0 Staterooms, 1000 Emergency Low Berths, 578.000 Tons Cargo

16 Escort (in hangar)s (20,000.000 tons, Crew 20, Cost MCr 0.000)

MCr 651,456.941 Singly (incl. Architects fees of MCr 6,450.069), MCr 516,005.498 in Quantity

240 Weeks Singly, 192 Weeks in Quantity

Minbari drives are pure gravitic, according to both RPG's and B5W. Pretty much, they cruise like naval vessels in water, can turn on a dime, etc.

Centauri and Narn ships have gravitics, but not, apparently, for drives.
Re: Gravitic drives -- is this similar to inertialess drives?

Doesn't seem to be; all three games I've played have them having inertia, but being able to change course for less than the required thrust.

In the full-thrust variant from the Chameleon Ecclectic Babylon Project RPG, Gravity Drive ships simply alter their inertial direction at midpoint and end point. One point of thrust will turn the ship 30°... at any speed.

Un B5W, it's not so pronounced, but it takes about half as much power to turn as newtonian vectors would require.
Just did some pack-of-the-napkin math for the Nike... if it's really a 1700 x 255 x 170 meter slab, then it displaces over 5 million tons.
I did some poking around with the Babylon 5 miniatures rules. They've classified ships based on mission:

Patrol - light, fast, small ships. Maps to fighters and small escorts.

Raid - light, medium-sized ships with an average acceleration. Maps to small escorts and destroyers.

Skirmish - mid-to-large sized, medium weapons. Maps to destroyers and light cruisers.

Battle - large ships, heavy weapons. Maps to heavy cruisers.

War - very large ships, heavy weapons. Maps to battleships.