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

Crakkerjakk 07-14-2008 02:47 PM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by safisher
I think it will be hard to see the changes coming at TL9 with the advent of metamaterials. The ships using them may be unrecognizable to us in their geometry as "stealth space ships" too.

I know we've talked about the viability of different metamaterials before, but he is right. No metamaterial will prevent the craft from having to radiate heat. Although whether future advances will allow one to chose which direction that heat is radiated may be up to debate, I think that the First Law of Thermodynamics will still apply even several tech levels removed from our current tech level.

safisher 07-14-2008 02:55 PM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by Crakkerjakk
I know we've talked about the viability of different metamaterials before, but he is right. No metamaterial will prevent the craft from having to radiate heat.

Yes but whether its the slam dunk "automatic detection" that many people assume is nowhere close to assured. The technology that is being experimented with now indicates that there are possible hard science solutions for electromagnetic spectrum shielding and cloaking. I'm surprised this is so controversial. As technology improves, detection, stealth, armor, and firepower are in a constant arms race. It only makes sense that in some future setting they will continue to be in contention. There's too much at risk not to develop ways to deal with the problem.

Crakkerjakk 07-14-2008 03:05 PM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by safisher
I'm surprised this is so controversial.

Honestly for me it's that whole First Law thing. It's one of the big fundamentals. I'm sure there will be a lot of research into making things harder to see, but the typical star trek-esque cloaking fields that come to mind when people start mentioning stealth in space(to me, at least) generally seem(again, to me) to be handwaving the First Law, which you just can't do. I think most research into stealth is going to be with reducing the power requirements of combat craft. Computer controlled ambushers, a la the AKVs of THS. The easiest way to lower power requirements of combat craft is to make it so they don't need to lug around life support systems, IMO.

Cernig 07-14-2008 03:40 PM

Re: [Spaceships] TL9 Military Spaceships
 
Hang on - doesn't that pod only give 45 missiles, not 75?

Langy 07-14-2008 05:40 PM

Re: [Spaceships] TL9 Military Spaceships
 
It's got 45 launchers - and each launcher has 5 missiles. I missed a multiplication in there - it has a total load of 225 missiles, not 75. A full nuke load would be $11,250,000. Still drastically under the cost of an equivalent conventional force.

As to the heat problem, two people and a minimum of electronic devices probably don't put out too much waste heat - but the amount they do put out is accounted for in the +3 IR signature, +4 when the fuel cell is active. I assume that heat sinks could also be used to help 'hide' the heat of the ship for a while, and if a Menippe is landed on an asteroid it could dump its heat into the 'roid, hiding it there.

The 100,000 mile distance between asteroids isn't too bad, either - that's still just half the distance of the Distant combat scale. Still not very good, of course - but well within the capabilities of the Menippe, with its 1G acceleration (with a module installed). This gives it the ability to get an Attack Vector on a foe in the 10 minute time scale, making the engagement range Long - well within range for these missiles against an SM+12 target. At this range, you could place Menippes on several asteroids up to two hundred thousand miles out in order to perform the ambush.

Cernig 07-14-2008 06:31 PM

Re: [Spaceships] TL9 Military Spaceships
 
*blink* 225 missiles on a 30 ton boat?

A 25 KT "physics package" weighs in at around 80 lbs and cannot be made lighter without superscience or contravening the laws of physics. That's 18,000 lbs (9 tons) right there.Then there's the propellent, guidance package, missile body etc. What range do these things have? How much is one supposed to weigh?

If this is RAW then I'm glad I've not bought the book. I'd just have to rewrite it anyway.

Edit: I just read Ultra-Tech on the subject of mininukes (TL9) and Antimatter warheads (Tl10). That's superscience, right there, even if you assume the technology is applied to higher yields. I personally don't believe a word of it will ever actually come to pass and wouldn't use it for a hard-science setting.

Langy 07-14-2008 07:14 PM

Re: [Spaceships] TL9 Military Spaceships
 
With an 80-pound nuclear package, you can easily build a 16cm missile using the Spaceships rules. With this design, the missile only has 6.3 miles per second delta-V and 4G acceleration - with a larger missile I'd use something similar to the Menippe for propulsion, a mini mag-orion in a missile massing around ten tons, making it a very long-range, high-speed weapon.

EDIT: Oh, and remember that the missile pod itself masses a total 30 tons while the boat that carries it also masses 30 tons. The whole delivery platform masses 60 tons.

Name: 16cm Nuclear Missile
TL: 9
dST/HP: 3
Hnd/SR: 2/4
HT: 13
Move: 4G/6.3 mps
LWt.: 0.1 Tons
Load: None
SM: 0
Occ: None
dDR: 0/0/0
Cost: $150,000


Front
[1] Warhead
[2] Warhead
[3] Warhead
[4] Warhead
[5] Fuel Tank (0.005 Tons Capacity)
[6] Fuel Tank (0.005 Tons Capacity)
[Core] Control Room (Complexity 2 Computer Network; Comm/Sensor Level -2)

Middle
[1] Warhead
[2] Warhead
[3] Warhead
[4] Warhead
[5] Fuel Tank (0.005 Tons Capacity)
[6] Fuel Tank (0.005 Tons Capacity)
[Core] Fuel Tank (0.005 Tons Capacity)

Rear
[1] Fuel Tank (0.005 Tons Capacity)
[2] Fuel Tank (0.005 Tons Capacity)
[3] Fuel Tank (0.005 Tons Capacity)
[4] Fuel Tank (0.005 Tons Capacity)
[5] HEDM Chemical Rocket (2G Acceleration, 0.5 Delta-V/Tank)
[6] HEDM Chemical Rocket (2G Acceleration, 0.5 Delta-V/Tank)

Crakkerjakk 07-14-2008 07:37 PM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by Langy
The 100,000 mile distance between asteroids isn't too bad, either - that's still just half the distance of the Distant combat scale. Still not very good, of course - but well within the capabilities of the Menippe, with its 1G acceleration (with a module installed). This gives it the ability to get an Attack Vector on a foe in the 10 minute time scale, making the engagement range Long - well within range for these missiles against an SM+12 target. At this range, you could place Menippes on several asteroids up to two hundred thousand miles out in order to perform the ambush.

All I'm saying is that if I were the captain of a vessel in known hostile territory, and there are only three places to hide in several billion cubic miles, I'd be keeping an eye on those three places fairly diligently.

Relevant anecdote:
When I was going through Marine Combat Training, we had a camouflage class. There was some classroom time on camouflage techniques, and then they released us into a dry gully in groups of two to camouflage a fighting position. We had about a half hour before the instructors would come try to find us. Me and my partner found a dry creek bed that was ideal, and we picked a spot where a small tree was growing out of the side of the creek bed. With a minimum of fuss, we had a position where our uniforms matched the foliage, and the round shapes of our helmets merged with the base of the tree so that there wasn't any obviously artificial silhouettes. When the instructor appeared, he walked right up to our position and greeted us.

I asked him how he had seen us. He said he hadn't, but because all the rest of the terrain had so little cover to offer, this tree was an obvious place to hide.

I'm not arguing the game mechanics of hiding on an asteroid. By the rules, it obviously would work well. The problem is, anyone who knows what they're doing will KNOW what a good hiding spot it is, and approach it with a suitable sense of caution. Or just hit it regardless of whether they detect anything, if it's actually a war and they don't have to worry about ammo(using lasers, perhaps.) Thats all I'm trying to say.

Langy 07-14-2008 07:56 PM

Re: [Spaceships] TL9 Military Spaceships
 
We're actually talking about a 400,000 mile radius sphere, centered upon the target. With one rock per 100,000 mile radius sphere, that's 64 asteroids within range. That's not just three hiding places - that's sixty-four hiding places, each of which is several hundred feet in diameter and thus quite a bit larger than the roughly forty-five foot long Menippe.

safisher 07-14-2008 08:05 PM

Re: [Spaceships] TL9 Military Spaceships
 
Quote:

Originally Posted by Crakkerjakk
I'm sure there will be a lot of research into making things harder to see, but the typical star trek-esque cloaking fields that come to mind when people start mentioning stealth in space(to me, at least) generally seem(again, to me) to be handwaving the First Law, which you just can't do.

I don't doubt this. The finer issue, really, is whether some material/ship design will prevent you from detecting the energy.
http://www.sciencedaily.com/releases...0529190038.htm
"This metamaterial has been engineered to ensure that all light is neither reflected nor transmitted, but is turned completely into heat and absorbed. It shows we can design a metamaterial so that at a specific frequency it can absorb all of the photons that fall onto its surface."

Seems that the power requirements of ships could be kept very small if light hitting it were converted into heat. Other articles mention how the materials can be tunable within a range of frequencies. This is at the infancy of the study of the materials, so, it seems safe to say that we don't fully understand exactly what the outcome is going to be.

Some of the real world designs place an umbrella like device between the spacecraft and the enemy, which greatly reduces the likelihood of detection. it's no cloaking device, but is could (possibly) show what futuristic hard science spacecraft will look like -- umbrella shields with metamaterials for many, many purposes (including lenses for sensors and weapons, and for stealth). Perhaps a such giant shield would serve all three purposes.


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