Further meditations on space combat

[BlackCat]

You're a ****.

Yeah, and you are an idiot

Please stay away until you are going to be serious (well, that can be a problem in a pure speculative thread).

[Patroklos]

Sensors. Well, they'll probably still be the same - optical and passive/active radar. The difference will be that several ships sensors will work together to build the "map".

We already do this via Link 4A/11/16

[Elok]

We're missing some key context here. Why are battles happening in space in the first place? What's the motivation to build a big ship and fill it with humans and send it flying around? Much more plausible is a bunch of ASAT satellites shooting each other down until someone has orbital superiority.

Yeah, I guess that needs to be filled in, but I was reluctant to do it for fear of getting bogged down in "that would never happen, there would obviously be a transnational federation of such-and-such versus the space Nazis." I guess we should presuppose that either planets in our system have been rendered habitable, or else that we have some kind of FTL drive, ONLY in the sense that we're assuming there's some reason to go into space in the first place. Presently there isn't, to my way of thinking anyway. I guess a lot does depend on the geo(astro?)-political realities, as in real war. Really, though, this thread is: "the Star Wars fighter model doesn't make much sense. How would it really work, if two spacefaring powers had to duke it out, in terms of known or at least vaguely feasible technology?"

KH, bearing in mind that I'm not a physicist and please don't yell at me, why would the ships necessarily be in orbit? That strikes me as the space equivalent of being in a harbor-you're stuck in one course that takes energy to move from, and therefore more vulnerable. I'd move out far enough from the planet to keep it in sight but not close enough to fall around it.

[Elok]

So this object hurtling at 100 miles per second relative velocity has maneuvering jets?

I think there's some confusion, that he thought you were asking about the ships. But as Patty said, maneuvering jets might be feasible on a shell, and would be valuable for course correction; if the shell were moving in a direction we'll arbitrarily call "west," it would of course have to continue moving "west," but jets could introduce a slant if the target is "north," "south," up or down. As for moving an object that fast, I'm too dumb and lazy to do/understand the math, but vacuum helps a LOT. The two systems I've heard of through wikisurfing are Gauss cannons and rail guns. Both have problems that could presumably be fixed.

Gauss cannons are a series of electromagnets that fire in sequence to sort of suck the shell down a tube at high speeds. Current problem: you can't turn off the magnet fast enough to keep it from holding the shell back. Rail guns rely on a pair of long, metal rails with the shell sandwiched between them. Give one rail a positive charge and the other a negative, and the shell is magnetically propelled along the channel real quick. So quick, in fact, that supposedly the rails tend to vaporize from friction after one shot. But then, you'd think the shell would vaporize too, so I don't get it. Anyway, maybe exposing the whole apparatus to the cold of space would mitigate the heat somehow? Beats me, I just like thinking about blowing **** up in space.

[BlackCat]

We already do this via Link 4A/11/16

Yeah, I know that there are some activity on this. My knowledge about it is from the danish ship Absalon that apprently uses some relatively new radar tech to find the pirates at ethiopia.

http://en.wikipedia.org/wiki/Absalon_class_flexible_support_ship

I get my info from the danish enginering society site, but that is in danish, so I guess it won't say you much

[Elok]

With sufficiently powerful mass drivers you don't actually impart all of the energy on impact - the 'hunk of metal' flies clean through the other ship causing minimal damage.

Really? Damn. Well, that would introduce a practical consideration: don't over-power your gun, or you'll have to use a warhead to make the enemy into powder. OTOH, the faster the shell the harder it is to deflect or intercept, so maybe you'd still want it fast.

[BlackCat]

KH, bearing in mind that I'm not a physicist and please don't yell at me, why would the ships necessarily be in orbit? That strikes me as the space equivalent of being in a harbor-you're stuck in one course that takes energy to move from, and therefore more vulnerable. I'd move out far enough from the planet to keep it in sight but not close enough to fall around it.

KH will probably beat me up, but you need both - close defense and "high sea flotilla".

[Elok]

Completely automated. If you need people to live there they can go once you've killed everything.

Bombard the planet with asteroids until you've wiped out all life or something

I think that even in the present day a genuine D-Day style invasion would be doomed to failure. Even more so if tactical nukes are deployed. Even worse in space, the lines of communication are so long and transports would be hugely expensive and massively fragile. There's very little downside to nuking stuff in space, there's no land there to ruin, but the invaders would probably want to preserve something (otherwise they'd have nuked it all from orbit, it's the only way to be sure)

I think you are thinking too much like WW-II in space.

I'm assuming you would not wait until the whole planet is controlled and covered by a rival power and a strong base established, complete with missiles capable of reaching orbit, before attacking. If you did, of course, it would be a royal ***** to take. And the problem with bombarding with asteroids (or nuking) is that they do substantial, indiscriminate damage to the real estate, drastically reducing its value to you. I certainly wouldn't want to drop a large asteroid on a habitable planet, I'd have to rebuild the whole damned ecosystem before I could use it. Not to mention humanitarian concerns for the civilians and not wanting to demolish all that useful infrastructure. Transports are expensive; rebuilding several cities with power plants and factories wouldn't be too cheap either. Don't buy into "the myth of space power."

[BlackCat]

Really? Damn. Well, that would introduce a practical consideration: don't over-power your gun, or you'll have to use a warhead to make the enemy into powder. OTOH, the faster the shell the harder it is to deflect or intercept, so maybe you'd still want it fast.

Well, he have a point, but then, there are no reason that it is a single lump. Just as a simple exaple - if the mass is steel rods bundled together that loose this "bundling" after firing, then you will have a shrapnel effect. The closer to the target when release, the better.

[BlackCat]

Elok, have you ever tried Imperium Galactica II ? It's not a very challenging game (except for figuring out that you may need to open the manual pdf to load the needed fonts), but it has a bit of this "protect planets - build attack fleet" flavor.

[Patroklos]

I rememeber that game, entertaining. I like Pax Imperia 2 better.