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-   -   [Spaceships] TL9 Military Spaceships (https://forums.sjgames.com/showthread.php?t=42270)

Agemegos 07-15-2008 12:44 AM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by safisher
I think you may miss what I am saying -- not that it's possible now, or that we even understand how it may work in the future, only that its very nearsighted to say that something is impossible. Science progresses very rapidly, and history shows us that time and again the impossible is possible. Perhaps there will be challenges to the second law? Perhaps it will stand. Who can say with certainty?

I can say with certainty that if the Second Law of Thermodynamics did fall in any way, then the effects on spaceship design would be far more profound than simply allowing stealth in space. For a start, you could replace the power plants with perpetual motion machines. A ship that could break the Second Law of Thermodynamics would not have to dick around with TL9 reaction engines.

In any case, defying any of the Laws of Thermodynamics or any of the fundamental conservation laws definitely calls for a "^" superscience descriptor.

Peter Knutsen 07-15-2008 03:15 AM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by Cernig
I'm personally dubious that stealthing would be of more than borderline stategic or tactical usefulness on anything using a nuclear pulse engine, or that anyone (at any TL) could shoehorn a 25 k-t yield nuke into a 6 1/2 inch missile, but other than that nice designs.

Edit: for comparison, the W-80 nuclear warhead - variable from 5 to 150 KT - (TL8) is 11.8 inches in diameter and can be loaded into the AGM-129 cruise missile (TL 8) which is 2 ft 5 inches in diameter and masses 1.3 tonnes at launch. Physics constrains just how small you can make a nuke.

One other thing - where Stealth would actually be useful is on the missiles, just like the AGM-129.

I don't know about 4th Edition, but at least one GURPS 3rd Edition book has rules for how small one can make warheads of various yields at different TLs.

Langy 07-15-2008 03:33 AM

Re: [Spaceships] TL9 Military Spaceships
 
The Von Braun-class of factory ships is designed to accompany a small fleet or task force of other vessels in order to supply them with mobile refueling and rearming. The Von Brauns are capable of mining asteroids and using that material to construct new ships, missiles, and nuclear bomb pulse units. They are also capable of refining water or nuclear pellets out of asteroids. The Von Brauns carry a large number of parasite drones which are used to collect the asteroid chunks the factory and refinery require.

Along with serving as a supply ship, the Von Brauns include a large number of entertainment and recreation establishments in their habitat ring, allowing them to serve as mobile entertainment barges for the task forces they accompany.

The Von Braun is also popular as a civilian ship type for Belter colonies or mining start-ups, though its extremely high cost is usually quite daunting for all but the largest corporations.

Name: Wernher von Braun-class Logistics Supply Ship
TL: 9
dST/HP: 300
Hnd/SR: -2/5
HT: 14
Move: 0.005G/144 mps
LWt.: 100000 Tons
Load: 8,475 Tons
SM: 12
Occ: 400 ASV
dDR: 70/70/70
Cost: $15,290,000,000


Front
[1] Armor, Advanced Metallic Laminate (70 dDR)
[2] Hangar Bay (3,000 Tons Capacity, 500 Tons per Minute Launch Rate)
[3] Cargo Hold (5000 Tons Capacity)
[4] Habitat (600 Rooms)
[5] Fuel Tank (5,000 Tons Capacity)
[6] Fuel Tank (5,000 Tons Capacity)
[Core] Control Room (20 Control Stations; Complexity 8 Computer Network; Comm/Sensor Level 10)

Middle
[1] Armor, Advanced Metallic Laminate (70 dDR)
[2!] Fabricator ($5,000,000 per hour)
[3!] Mining System (500 Tons per Hour)
[4!] Chemical Refinery (1500 Tons per Hour)
[5] Fuel Tank (5,000 Tons Capacity)
[6] Fuel Tank (5,000 Tons Capacity)
[Core] Fusion Reactor (2PP, 50 Years Operation)

Rear
[1] Armor, Advanced Metallic Laminate (70 dDR)
[2!] Fabricator ($5,000,000 per hour)
[3] Fusion Reactor (2PP, 50 Years Operation)
[4] Fuel Tank (5,000 Tons Capacity)
[5] Fuel Tank (5,000 Tons Capacity)
[6] Advanced Fusion Pulse Drive (0.005G Acceleration, 20 Delta-V/Tank)


Design Features
Spin Gravity

Habitats
200 Cabins (Full Life Support)
50 Establishments
5 Offices
95 Steerage

Langy 07-15-2008 09:02 AM

Re: [Spaceships] TL9 Military Spaceships
 
The ME-2 Artemis-class electronic warfare module is designed to provide point-defense and electronic warfare support to other ships in a battlegroup, from other Menippe-class utility ships to, when used in tight formation with other Artemis EW pods, much larger ships such as a frigate or cruiser. Aside from their electronic warfare support, Artemis pods can supply vast quantities of point-defense fire, especially effective against enemy missile swarms.

This module design assumes a ship can 'lend' its Defensive ECM bonus to other ships it is in tight formation with - an assumption that I believe makes perfect sense. In order to provide a -2 bonus to a ship one size modifier larger, three ECM modules are required - with the Artemis, it can provide a maximum of a -2 bonus to a single SM+7 vessel, a maximum -6 bonus to a single SM+6 vessel, or a maximum of a -6 bonus to each of three SM+5 vessels.

Name: ME-2 Artemis
TL: 9
dST/HP: 20
Hnd/SR: 0/4
HT: 13
Move: 0.005G/144 mps
LWt.: 30 Tons
Load: 8,475 Tons
SM: 5
Occ: 400 ASV
dDR: 5/5/5
Cost: $5,540,000


Front
[1] Armor, Advanced Metallic Laminate (5 dDR)
[2] Defensive ECM
[3] Defensive ECM
[4] Defensive ECM
[5] Large Multipurpose Sensor Array, Front (Comm/Sensor Level 6)
[6] Medium Weapons Battery (3 2cm VRF Gun Turrets, 1000 shots each)
[Core] Control Room (1 Control Station; Complexity 4 Computer Network; Comm/Sensor Level 3)

Middle
[1] Armor, Advanced Metallic Laminate (5 dDR)
[2] Defensive ECM
[3] Defensive ECM
[4] Defensive ECM
[5] Medium Weapons Battery (3 2cm VRF Gun Turrets, 1000 shots each)
[6] Medium Weapons Battery (3 2cm VRF Gun Turrets, 1000 shots each)
[Core] Large Multipurpose Sensor Array, Middle (Comm/Sensor Level 6)

Rear
[1] Armor, Advanced Metallic Laminate (5 dDR)
[2] Defensive ECM
[3] Defensive ECM
[4] Defensive ECM
[5] Medium Weapons Battery (3 2cm VRF Gun Turrets, 1000 shots each)
[6] Large Multipurpose Sensor Array, Rear (Comm/Sensor Level 6)


Design Features
Stealth Hull (Stealth Bonus: 6)

lwcamp 07-15-2008 10:57 AM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by safisher
And if the metamaterials are also working on the IR signature?

You can have all the fancy metamaterials you want. It doesn't alter that each person in the spacecraft will be generating on the order of 0.3 joule/kelvin of entropy every second. A typical 1 kW appliance will be dumping around 3 joule/kelvin of entropy into the spacecraft environment (assuming the is exhausting its waste heat into a room temperature environment). Add up the demands for lighting, life support, computing, communication, and sensors. Now you have the total entropy load that must be disposed of every second. In space, the only way you can dispose of this is to radiate it. Otherwise, energy and entropy build up until the crew cooks (or the microchips suffer heat failure). If you have fancy metamaterials that prevent radiation, you are simply preventing the spacecraft from getting rid of its waste until it cooks.

We have materials today that minimize radiation. A smooth aluminized surface will do a very good job at keeping an object from radiating (or silvered, or gold coated. Gold is actually best for minimizing radiation from room temperature objects). You don't need metamaterials for reducing radiated heat. But saying that coating a craft in metamateriasl eliminates its need to dispose of heat is like saying that coating a person in impermeable plastic will eliminate his need to dispose of metabolic wastes.

Quote:

Originally Posted by safisher
Heh, I suspect it will require a hull with some sort of multispectral material(s). But clearly it will route the energy in some desirable manner, say, straight away from the enemy. With a big umbrella cloaking you in the front, and your hull converting heat into light and pushing it out the back (or directing it into your laser battery) who knows. Maybe it will be converted to gravitons for reactionless propulsion? I have no idea.

You cannot convert heat (energy with associated entropy) entirely into laser light (energy without any associated entropy). You need to get rid of the entropy (<rant>Everyone always forgets about the entropy! They assume that once you deal with the energy accounting, everything is fine. One of the greatest advances in physics, the second law of thermodynamics, is entirely overlooked</rant>).

Anyway, you can, to some extent, direct your waste radiation. It always requires a larger and bulkier radiator assembly than if you radiate in all directions. It is not to difficult to restrict your radiation into half of the sky, it is very very difficult to restrict your radiation into a narrow cone. The issue now is how do you direct your radiation so the enemy doesn't see it. Now here's the problem - the enemy will undoubtedly be looking from all sides. If you have sufficient forces to have shot down all his picket drones and observational platforms all over the solar system, you've pretty much already won the battle for this solar system, and all that is left is mopping up. There is also the issue that a picket drone with only low power electronics can be much harder to see than any spacecraft that you actually want to do something -so you will not know where your radiated power should not go.

In any event, gravitons for reactionless propulsion is clearly not TL9 non-superscience like this thread is about.

Quote:

Originally Posted by safisher
But clearly we are in a very early stage for this type of thing. Who can possibly say with certainty "cloaking in space is superscience" when the advances of metamaterials are continually moving forward?

Because even metamaterials are limited by the constraints of physics. They can do some amazing things, yes. But they are still physical systems and subject to physical laws. They cannot make entropy go away.

Luke

Peter Knutsen 07-15-2008 11:27 AM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by safisher
"There is not the slightest indication that nuclear energy will ever be obtainable. It would mean that the atom would have to be shattered at will." Albert Einstein

"Heavier-than-air flying machines are impossible." Lord Kelvin.

I think you may miss what I am saying -- not that it's possible now, or that we even understand how it may work in the future, only that its very nearsighted to say that something is impossible. Science progresses very rapidly, and history shows us that time and again the impossible is possible. Perhaps there will be challenges to the second law? Perhaps it will stand. Who can say with certainty?

Was Einstein referring to a Physical Law(tm) when he said that nuclear energy was impossible? Was Lord Kelvin?

Peter Knutsen 07-15-2008 11:30 AM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by Langy
The ME-2 Artemis-class electronic warfare module is designed to provide point-defense and electronic warfare support to other ships in a battlegroup, from other Menippe-class utility ships to, when used in tight formation with other Artemis EW pods, much larger ships such as a frigate or cruiser. Aside from their electronic warfare support, Artemis pods can supply vast quantities of point-defense fire, especially effective against enemy missile swarms.

This module design assumes a ship can 'lend' its Defensive ECM bonus to other ships it is in tight formation with - an assumption that I believe makes perfect sense. In order to provide a -2 bonus to a ship one size modifier larger, three ECM modules are required - with the Artemis, it can provide a maximum of a -2 bonus to a single SM+7 vessel, a maximum -6 bonus to a single SM+6 vessel, or a maximum of a -6 bonus to each of three SM+5 vessels.

I think that this design in particular calls for my house ruled Super-Sized Sensor/Comms Array. You'd power up your module a lot, and you only have to sacrifice 2 weapon slots.

safisher 07-15-2008 12:44 PM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by lwcamp
In space, the only way you can dispose of this is to radiate it.

Right. If you can prevent, even for a brief time, in some limited manner, the enemy from detecting your emissions, the result is much better than "stealth is impossible." That's all I'm saying.

Quote:

Originally Posted by lwcamp
But saying that coating a craft in metamateriasl eliminates its need to dispose of heat is like saying that coating a person in impermeable plastic will eliminate his need to dispose of metabolic wastes.

I haven't said that. And who is saying the ship must have people aboard it, anyway?

Quote:

Originally Posted by lwcamp
You cannot convert heat (energy with associated entropy) entirely into laser light (energy without any associated entropy).

Even if its not entirely, the point still stands that ships will likely make use of materials and energy in ways we don't today.

[QUOTE=lwcamp]The issue now is how do you direct your radiation so the enemy doesn't see it. Now here's the problem - the enemy will undoubtedly be looking from all sides. . . . so you will not know where your radiated power should not go[QUOTE=lwcamp]

The tactical employment argument is the weakest. I can think of many scenarios in which a ship would benefit tactically from being able to radiate in one direction. Stealth systems today are highly limited in their employment too, but we still spend billions to research and produce them.

Quote:

Originally Posted by lwcamp
Because even metamaterials are limited by the constraints of physics. They can do some amazing things, yes. But they are still physical systems and subject to physical laws. They cannot make entropy go away.

I'm not arguing that the laws will be handwaved, only that the materials (and in particular, ship geometry) could produce effects that could meaningfully reduce a ship's signature without reducing such claims to "superscience."

martinl 07-15-2008 01:56 PM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by Agemegos
I can say with certainty that if the Second Law of Thermodynamics did fall in any way, then the effects on spaceship design would be far more profound than simply allowing stealth in space. For a start, you could replace the power plants with perpetual motion machines.

Very few settings with FTL deal with the inevitable time travel spin off technologies. Is stealth with the rest of thermodynamics untouched very different?

Diomedes 07-15-2008 02:17 PM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by martinl
Very few settings with FTL deal with the inevitable time travel spin off technologies. Is stealth with the rest of thermodynamics untouched very different?

Certainly not, as long as you hang the superscience caret on it, and don't confuse it with actual science.


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