Steve Jackson Games Forums - [Spaceships] Eclipse Phase Spacecraft

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Re: [Spaceships] Eclipse Phase Spacecraft

Try the Stealthed Landing Pod from Firewall.

"This landing pod is 3.5 meters tall, 3 meters in diameter [volume = 873.7 cf; surface area = 507.2 sf], and has a mass of 3 [metric] tons [empty?] [SM+3]. In addition to room for six morphs [6 * 200 lbs. = 1,200 lbs. (0.6 sh tn) = 3.907 sh tn total [SM+3.2]], it features a cargo hold with room for up to 8 medium-sized* pieces of gear and numerous smaller items."

*Medium size items are cumbersome to hold with one hand, ranging from the size of a 2-liter bottle to the size of a medium dog. They do not fit in pockets, but they may be concealed by larger coverings. Large = Roughly human-sized.

Since it's so small, it might not even have seats (which is fine, because it's usually drifting).

Re: [Spaceships] Eclipse Phase Spacecraft

Quote:

Originally Posted by Eukie (Post 2280862)

Fast Courier

Code:

Front    System

[1]      Advanced Laminate Armor (dDR 10)

         Fuel Tank (33 tons providing 28 mps)

[2-4]    Fuel Tanks (each 50 tons providing 84 mps)

[5-6]    Cargo Holds (100 tons)

[core]   Control Room (C8, comm/sensor 6, 3 control stations)

         Habitat (12 bunks, 1 Luxury Cabin, 1 Mini-Nanofac, see notes)

Centre   System

[1]      Advanced Laminate Armor (dDR 10)

         Fuel Tank (33 tons providing 28 mps)

[2-6]    Fuel Tanks (each 50 tons providing 84 mps)

Rear     System

[1]      Advanced Laminate Armor (dDR 10)

         Fuel Tank (33 tons providing 28 mps)

[2-6]    5x High Thrust Antimatter Plasma Rocket (0.01 G)

[core]   Fuel Tank (50 tons providing 84 mps, see notes)

Code:

TL            10

Spacecraft    Fast Courier

dST/HP        70

Hnd/SR        -3/5

HT            12

Move          0.1G/924 mps

LWt.          1,000

Load          101

SM            +8

Occ           13SAV

dDR           10

Cost          565,000,000

Notes
The Fast Courier is TL11 for Complexity purposes (p. SS8-6).

The Fast Courier runs on antimatter-boosted hydrogen/water, for a refueling cost of $600M per tank. Since antimatter production in Eclipse Phase is mature and large-scale, it may be reasonable to lower this to the same cost as antimatter-catalyzed hydrogen/water, for $1M/tank.

As always, the exact habitat makeup is speculative.

Each of the two Habitat small spaces can be exchanged for 167 tons of extra cargo holds, reducing the cost by 300K each. (And an additional 1M if the Mini-Nanofac is removed.) This reduces occupancy to 3AV.

Each of the two Cargo Holds can be exchanged for 6 cabins, increasing the cost by 1M per system exchanged.

While Spaceships has all fuel tanks for antimatter-based fuels be treated as Volatile systems, it seems rather reasonable to allow the antimatter to be concentrated in a single system: in this case a [core] fuel tank. The other Fuel Tanks should therefore not be considered Volatile systems.

The three control stations can be removed for a 150K reduction in cost.

The Fast Courier can have the Self-Healing feature (p. SS7-22) for a +2M to cost.

You cannot decrease the cost of antimatter production without superscience though, which would make the setting TL11^. If you want to preserve realism, antimatter is going to cost out the nose. I will explain.

So, one gram of antimatter possesses 90 TJ of energy content, which is the equal to 25 GW-H of electricity ($2.5 million worth of retail electricity at TL8). At TL11, antimatter is $25 million a gram, so the reaction mass probably contains 24 grams per metric ton. If we assume the same energy prices as TL8, the efficiency is 10%, meaning that you would need a 99.9% drop in energy prices for antimatter to be as cheap as you want.

Re: [Spaceships] Eclipse Phase Spacecraft

Quote:

Originally Posted by AlexanderHowl (Post 2283470)

Antimatter production using cheap electricity from manufacturing plants near the Sun is an element of the Eclipse Phase setting.

Re: [Spaceships] Eclipse Phase Spacecraft

Quote:

Originally Posted by Eukie (Post 2283553)

Antimatter production using cheap electricity from manufacturing plants near the Sun is an element of the Eclipse Phase setting.

Yes, I understand that, but that is part and parcel of the underlying assumptions about antimatter production in most settings, so Eclipse Phase would have to be doing something different. If the Eclipse Phase setting could produce electricity for $100/GW-h, they would hardly have any social issues. Such a society would be unbelievably wealthy, as they could practically do anything that they wanted.

What can you do with a GW-h? A human being possesses an average energy content of around 750 MW-h, so the energy content of a human being would be worth $75. Even at a 10% efficiency, you could make a human body out of raw elements for $750. One of the central elements of Eclipse Phase is the lack of resources to make physical bodies for digital entities, an element that could not realistically exist if energy was worth only $100 per GW-h of electricity.

Re: [Spaceships] Eclipse Phase Spacecraft

Quote:

Originally Posted by Eukie (Post 2280772)

RPG industry luminary John Snead wrote the spacecraft chapter for the Eclipse Phase roleplaying game and in discussions on the EP forums revealed that the designs were fairly realistic and provided the vital performance numbers for the various spacecraft.

Might you have similar info that would allow you to GURPSify the "Courier Morph", 1.5 metres tall, which uses a metallic hydrogen rocket to accelerate at a quarter gee for 90 minutes?

Re: [Spaceships] Eclipse Phase Spacecraft

Quote:

Originally Posted by AlexanderHowl (Post 2283557)

What can you do with a GW-h? A human being possesses an average energy content of around 750 MW-h, so the energy content of a human being would be worth $75. Even at a 10% efficiency, you could make a human body out of raw elements for $750. One of the central elements of Eclipse Phase is the lack of resources to make physical bodies for digital entities, an element that could not realistically exist if energy was worth only $100 per GW-h of electricity.

This is a bizarre economic model. I don't know what 'energy content of a human being' means, but there's no possible meaning that would make that a sensible approach to cost estimation.

Manufacturing capacity, not raw energy or common matter, is probably the actual limitation.

Re: [Spaceships] Eclipse Phase Spacecraft

Quote:

Originally Posted by DataPacRat (Post 2289182)

Might you have similar info that would allow you to GURPSify the "Courier Morph", 1.5 metres tall, which uses a metallic hydrogen rocket to accelerate at a quarter gee for 90 minutes?

To answer my own question, by abusing Spaceships' scaling rules more than a bit, I seem to get a reasonable approximation. Anyone see a way to improve this draft?

GURPS Spaceships Courier Morph:
(1.5 m tall, lacks legs, has arms, metallic hydrogen rocket (accel 0.25 G, delta-v 8.2 mps), plasma sail (accel 0.01G, 3 months, delta-v up to 480 mps))
* TL10, Unstreamlined
* Hull: SM+0: 0.1 ton (200 lbs), length 2 yards, dST/HP 3
* Design Switches:
- Advanced Computers
* Design Features:
? Self-Healing: $2,000
? Stealth $5,000
? Chameleon: $3500
? Hardened armor: +$1500
* Systems:
- 12x SM+0 fuel tanks: 0.06 tons (120 lbs) fuel ($360), delta-v 8.4 mps, $360
- 3x SM+0 Nanocomposite Armor, dDR 1, $500x3 = $1,500
- 1x SM+0 Control Room: Complexity 5, Comm/Sensor -1, 0 control stations, $200
- 2x SM+0 Robot Arm: $1,000*2 = $2,000
- 1x SM+0 Magsail: 0.001G, req 1 PP to turn on, $1,000
- 0.5x SM+0 Power Plant, MHD Turbine (1 PP for 12 hours), $50
- 3.75x SM-2 cargo bays: 3.75 lbs capacity
- 1.25x SM-2 HEDM Rocket: $37.50, 0.25G accel
* Total Cost: $5,147.50 to $17,147.50, $360 to refill tanks
- cargo capacity 3.75 lbs, loaded weight 200 lbs, empty weight 76.25 lbs
- air performance (up to .25 gees): 125 mph
- active sensors: 0.5 light-seconds (93,000 miles), comm range 0.5 AU (46M miles)