Space Fighters

[toddjh]

I think space combat (if such a thing ever takes place, which I kind of doubt) will be all about stealth. With high-powered lasers, if they can see you, they can kill you in less than a second. The only way to survive will be to avoid detection in the first place.

Ships will be black, radar-absorbent, and probably mostly spherical to minimize surface area. I would expect just enough armor to withstand impacts with random space debris -- weapons will be so powerful that defense is a non-issue.

I don't think designers will be concerned with rotating to simulate gravity, either -- I think it's more likely that we'll simply find some way of treating the physiological effects of zero-g on an individual basis. A ship with a rotating section large enough to accomodate the crew would have a fair amount of angular momentum, and that will be a huge liability in maneuvering. Remember the high school experiment where you spin up a bicycle wheel with handles, and then try to turn it?

There won't be a lot of dramatic acceleration, either, at least with rockets. If you don't want to get spotted, you'll set your course from a very great distance or from behind cover, and then coast into weapons range. New or exotic propulsion systems might change this, though.

The big problem will be heat. Powerplants large enough to power offensive lasers will probably put out a fair amount, and even human bodies alone will contribute to the problem. You want to be able to radiate that waste heat away when things are calm, but hide it when you're running silent. I'm picturing retractable radiator fins.

Even so, you'll still be generating the heat when you're trying to stay invisible, so you have to have some way to conceal it. Make the hull as close to a perfect insulator as possible. Then the problem becomes that the interior of the ship gets hotter and hotter the longer it stays hidden. No problem -- carry a huge chunk of ice, or something like it, as a heat sink. Not only does it absorb heat because it's cold, it also absorbs extra heat as it melts. You can freeze it again when combat is over and you don't have to worry about being spotted.

I don't think missiles will work as weapons. In order to be fast and maneuverable, they'll have to have a lot of exhaust, which makes them very easy to track. Fast as they are, lasers would have no trouble shooting them down. Projectile weapons are inferior to lasers in just about every way, so they're out, too. Mines might be an effective tactic if you're on the defensive.

In any case, I wouldn't expect space battles to be very dramatic. Most likely they'd consist of long periods of total inactivity, followed by a few seconds of bright light, and that would be it.

Jeremy

 

[geni]

I think space combat (if such a thing ever takes place, which I kind of doubt) will be all about stealth. With high-powered lasers, if they can see you, they can kill you in less than a second. The only way to survive will be to avoid detection in the first place.

So I just taget your planet which means you have to reveal yourself.

 

[Rolfe]

As I recall, Harlan Ellison was a consultant on the show, and may have had an idea or two.

Having met Harlan Ellison a few times, and read quite a lot of his writing, I think it's highly unlikely he knows the first thing about physics of this sort. (The rest of my comments about Harlan Ellison's personality would get this thread moved to Flame Wars.) They did have other people who might have known what was what in that area though.

The DVD comment says they asked NASA to all the things "Starfuries" if they ever actually materialised - be interesting to see if they ever do.

Rolfe.

 

[toddjh]

So I just taget your planet which means you have to reveal yourself.

Hmm? I'm not sure what you mean. Do you mean you hold the planet hostage to try to force them to surrender? I don't think that will work. If they know where you are, they'll just blow you up.

Planets can't be hidden, obviously, so there's no need to worry about staying quiet there. Planets will be packed with the latest radar and other active detection systems, and even a very stealthy ship will be spotted and destroyed quickly. Planetary lasers (either ground based, if practical, or on orbiting platforms) will be hugely powerful, because they are static and close to resources. I don't think planets will be major players in space combat; planetary warfare will more likely be economic, or by smuggling weapons down to the surface.

Jeremy

 

[Kaon]

For the future spacewars I don't think one-manned fighters like the ones we have today in the form of fighter jets will be the backbone of any fraction. Making war in space is, however, an extremely complicated process that will be nothing like the wars ever fought on the surface of this planet.

Now, as far as fighters used only in space I think is pretty much out of the question. What you want in that shipsize is something more versatile. The best thing would probably be some sort of multi-enviroment, long range, stand-alone weapons platform. Something that can maneuver with a certain degree of ease in space, but can also descend into an atmosphere-enviroment like the surface of a planet.

These platforms will not have a major role in open battle, but rather do hit-and-run missions in space, reconniscance missions, as well as several types of missions on the surface ranging from larger scale bomb attacks to smaller precision warfare stuff.

They also ought to have quite a long range, not beeing immediately dependent on carrier support. The best would be if they could operate as independently as possible. That would of course require mighty efficient power- and lifesupport systems.

As far as open battle goes, large scale attacks and so forth, I would guess that the bigger the better. I mean really large destroyers, cruisers, battleships, you name it! They will sport an array of weapons for different purposes. Also, they would need to have very advanced and massive hulls, composed of extremely durable materials to prevent antimatter from chewing through, or high-velocity objects from penetrating.

For weapons systems there are several possibilities. I would like to go through a few from the top of my head.

Lasers: Point, shoot and hit. Extremely hard to evade, a laser battery can be effective against anything from smaller objects (missiles, torpedoes, rocks etc.) to quite large vessels. Downside is the loss of effect over distance, so even though the light travels on and on, the effect is not sustained indefinately. I would suggest they're better for close range defence, for taking out smaller objects like mentioned above. It was also mentioned that lasers can be "neutralized" by having a highly reflective surface. That may indeed be the case, but if you have a highly reflective surface, you're also highly visible on the most primitive of radarscreens, and other weapons might take you out with ease. If you choose to go stealthy, however, you're harder to hit, and if the surface manages to disperse heat quickly enough, you might just get that much further.

Nukes: A nuke in space won't be nearly as effective as one on the ground. You could almost say, as a rule of thumb, that one nuke on the ground, is worth ten in space. I don't know if that's a good comparison, because the workings of a nuke changes from ground to space. In space you'll get no serious blast, you'll get no thermal radiation (so no need to pack your marshmallows just yet). The only significant effect a nuke would have in space is radiation which, however, will kill just as effectively in both directions, so forget the nukes for now. Wait until you've got space superiority, then bring in the nukes and burn the planet down (unless you want it for something as it is, or just have scruples).

Antimatter: This is some fun stuff! When matter and antimatter comes together they become light (although not necessarily in the good way). The annihilation of matter/antimatter produces highenergetic gamma rays that also spreads out in all directions and might as such not be very pleasent. Another downside is that any given amount of antimatter can only annihilate the equal amount of matter, meaning that if you have one kg of antimatter, you're only going to annihilate one kg of matter. So, you would need a lot of it if you want to do any damage, and don't forget you have to transport it, so steady as she goes.

Mass drivers: Throwing around projectiles is old stuff, but it takes on a whole new dimension in space. There need not be a limit to the effective range of projectiles, depending on the amount of erosive matter it has to travel through. Think twice before you start using these, or you might end up killing yourself on a later occasion.

Now, there's a lot more to be said on the subject, but I think I'll leave it at this for now. Except I just wanted to show you som pictures of a potential space fighter like the one I described in the beginning:

Tigress

 

[geni]

Hmm? I'm not sure what you mean. Do you mean you hold the planet hostage to try to force them to surrender? I don't think that will work. If they know where you are, they'll just blow you up.

They know ehere I am anyway I'm not wasteing resources on all that stelthing stuff I've just gore for straight numbers

Planets can't be hidden, obviously, so there's no need to worry about staying quiet there. Planets will be packed with the latest radar and other active detection systems, and even a very stealthy ship will be spotted and destroyed quickly. Planetary lasers (either ground based, if practical, or on orbiting platforms) will be hugely powerful, because they are static and close to resources. I don't think planets will be major players in space combat; planetary warfare will more likely be economic, or by smuggling weapons down to the surface.

Jeremy

Can they stop the cheap but effective 100,000 od nukes I've thrown at them?

You can't bring your enermy to battle in space if they wan't to avoid combat they can. You also can't control large areas because of the 3D nature. The only way to bring your oposition to combat is to attack thier palnets so that is what you attack. Nukes are going to give you as much destructive powers as you could posibly need and anti matter bombs more so. Then it is just a choice between expensive tageting systems or more nukes.

 

[AWPrime]

Re: Re: Space Fighters

Lasers: Point, shoot and hit. Extremely hard to evade, a laser battery can be effective against anything from smaller objects (missiles, torpedoes, rocks etc.) to quite large vessels. Downside is the loss of effect over distance, so even though the light travels on and on, the effect is not sustained indefinately.

But in a vaccuum you will have a better time hitting things in long range than in earth.

I do think they will be able to make a kill over a range of several light-seconds.

The only significant effect a nuke would have in space is radiation which, however, will kill just as effectively in both directions, so forget the nukes for now.

Just make focused nukes, it should be possible.

 

[toddjh]

Can they stop the cheap but effective 100,000 od nukes I've thrown at them?[/B]

100,000 nukes are not going to be cheap -- that's way more than the combined arsenal of the U.S. and U.S.S.R. at the height of the cold war. And how are you going to launch them? Planet to planet? That's a hell of a lot of fuel you're talking about, especially if you want them to get there in under a year or two. And if you're carrying them on a ship, you have to make sure the ship doesn't get blown up first, and so we're back to stealth.

You can't bring your enermy to battle in space if they wan't to avoid combat they can.

Which is why I'm skeptical that space combat will ever happen at all. It simply doesn't make any sense to fight for a planet from space, and there aren't really a whole lot of other targets out there.

Jeremy

 

[geni]

100,000 nukes are not going to be cheap -- that's way more than the combined arsenal of the U.S. and U.S.S.R. at the height of the cold war.

Remeber they had a shortage of radioactive material and were working with pretty basic technology. I'm assuming some form of nulcear power as standard which would raher solve the materials problem.

And how are you going to launch them? Planet to planet? That's a hell of a lot of fuel you're talking about, especially if you want them to get there in under a year or two. And if you're carrying them on a ship, you have to make sure the ship doesn't get blown up first, and so we're back to stealth.

Lots and lots of small ships

Which is why I'm skeptical that space combat will ever happen at all. It simply doesn't make any sense to fight for a planet from space, and there aren't really a whole lot of other targets out there.

Jeremy [/B]

People will always find reasons to fight however I think MAD would take over pretty fast.

 

[Bikewer]

The rationale given by Bear in the books mentioned (and also in Saberhagen's Berserker series) is that an advanced civilization might come to the conclusion that it was safer to destroy any potentially-competetive races first.

Thus the reason for the radio-frequency silence in the galaxy; no one wants to draw attention to themselves.

 

[Xeriar]

Which is why I'm skeptical that space combat will ever happen at all. It simply doesn't make any sense to fight for a planet from space, and there aren't really a whole lot of other targets out there.

Except for keeping people from dropping rocks on you.

The best analysis would be to evolve from that point, really - the detection and elimination of R-bomb threats and ways to counter them.

 

[Ziggurat]

Re: Re: Space Fighters

I'm going to talk about inter-planetary space combat, rather than inter-stellar space combat (which would mostly focus on attacking planets). I think what people aren't really thinking about are what are the targets going to be in a space-based war? The targets are mostly going to be large infrastructure that you can't maneouver. Stuff like orbital space stations, asteroid mining complexes, that sort of thing. Space is simply too big to track down and kill anything capable of significant movement. The question then becomes, how do you attack that, and conversely, how do you defend that?

Well, you attack that with missiles (probably nuclear, although as mentioned already, the bang in space isn't as powerful since you don't produce a shockwave and most of the radiation just heads out into deep space harmlessly). You launch those issiles launched from a VERY long distance away, and they approach their target as fast as you can possibly make them, to minimize the time in which defenders can try anything. Nukes will take out any exposed structure - you're not going to get a space ship to survive a hit with a nuclear weapon, so you don't use ships for close-up combat. You also coat the missiles with flat, reflective surfaces. Unless an observer gets lucky and catches the mirror at exactly the right angle to reflect the sun (and there should only be one angle for that), it will be close to invisible when not actually firing rockets (BTW, that's the same idea behind the angular shape of the F117 stealth fighter). Mirrored surfaces also protect against lasers, so even if the defender sees the missile when it gets close, it's hard to take them out (remember, they're traveling VERY fast by the time they reach their target).

There's a few things you can do to try to defend agaiInst such an attack. One is bury your stations inside an asteroid. A hundred feet of rock will stop just about anything. If you have a small space station, making it maneoverable can save you too - since nuclear explosions in space will dump most of their energy as radiation that zooms off harmlessly into space, rather than creating a superheated gas ball as it does on earth, dodging may be possible. Lasers will definitely be used, although with mirrored surfaces, it's no guarantee you can kill it even if you can track it. You'll also need a defensive network of eyes stationed some distance away from you - missiles will probably need to keep an unmirrored surface open on their back side for thrust and maneouvering, as well as possible communications with home (good idea to be able to abort an attack, as well as update target info, during flight), so even if you can't spot it coming at you, your network of eyes might spot it after it enters their perimeter. Your eye network would communicate with base via lasers, so that they'd remain essentially invisible to attackers and thus pretty much impossible to take out.

Lasers are going to be primarily defensive weapons. Defenders can put lots of them around their stationary targetsd, so an attacker can't match them going toe-to-toe with anything that moves fast. And if you don't move fast on the attack, you won't survive (you'll be a target for missiles for a long approach journey). So lasers are out of the question as a primary attack option.

Antimatter is cool, but you need energy to create antimatter, and it's always going to be wildly inefficient to produce. So from a simple economic perspective, it will simply NEVER make sense to use antimatter as a general-purpose weapon. You're always going to be better off just using that energy and money producing fleets of many more nuclear weapons instead. The only case where antimatter might be better is sneak attacks/sabotage.

Rail guns are neat, but you can't hit targets reliably millions of miles away with them, so they're only going to be useful for defense as well. However, they might serve some purpose for anti-missile defense: fire small particles at a very high rate to essentially create a cloud of bullets to intercept an incoming missile. High velocity of the incoming missile, regardless of the speed of the railgun projectile, will probably ensure destruction of the missile. But again, you've got to be able to detect the missile coming in, and unless the gun is pretty much right on the target, hitting an incoming missile is still going to be VERY tough (especially if it decides to do last-minute evasive actions as it approaches the target).

So basically, ships wouldn't be used for dirrect assault. But you would use ships as mobbile missile batteries - maneouver them around in preparation for launching assaults on the target of your choice, but the ships themselves would not engage directly. Ship-to-ship combat will not happen, because it's simply to easy to avoid contact - at interplanetary speeds, it's simply not going to be possible match speeds and locations of an enemy ship. Imagine two flies in a stadium zipping around at 100 miles an hour (and appropriately large turning radii). Now imagine them trying to grapple mid-flight. It's just not going to happen.

 

[Carn]

Except for keeping people from dropping rocks on you.

The best analysis would be to evolve from that point, really - the detection and elimination of R-bomb threats and ways to counter them.

I think the name R-bomb is not perfectly fitting, because a even larger thread would be asteroids.
Does anyone know how much energy it would require to get a 10 km asteroid localized in the asteroid belt, get on collision course with earth?

The big advantage is that practically all the impact energy is supplied by gravitation, the only thing you need to do is give it a small punch and have good computing power, because it will hit or miss after 1 or more years and no chance to correct in between.

And 10 km is certainly now size limit.

Carn

 

[Rolfe]

[another Babylon 5 derail]
That's how the Centauri totalled Narn.
[/derail]

Rolfe.

 

[Camillus]

If you want to know in detail about the likely realities of space combat then I suggest going here.

In my (non-expert) opinion though combat space craft will fall into three main classes: large, fast, armoured, heavily automated battleships with a small human command crew operating from inside a heavily shielded “storm cellar”. Those battleships will launch small, fast autonomous kill vehicles (AKV’s) and true missiles (operating as kinetic kill munitions (KKM), nuclear weapon platforms or bomb-pumped x-ray lasers) fired in large salvoes from long distance.

AKV’s are the ‘fighters’, although they’ll be piloted by AI’s or expert systems rather than wasting space on life support for a human. They’ll have two mission profiles: hunter-killer (HK) where they track enemy ships and either ram them for a kinetic kill or deploy some sort of nuke or kinetic weapon at relatively short range to achieve target destruction. Their other mission will be screening the battleship from enemy missiles or AKV’s and they’ll probably use some sort of KKM pods that allow them to scatter high velocity particles (ball bearings work well) into the path of incoming vehicles.

Either way there won’t be a lot of manoeuvring going on because there is no stealth in space. All (realistic) space craft are easily detectible at long ranges; they’re incredibly hot compared to the background of space and any drive they use is even hotter. For example the manoeuvring thrusters of a space shuttle in orbit around Earth can be detected from beyond Mars using current technology passive sensors. If that shuttle fires its main engines you can detect them from beyond Pluto. A realistic fusion torch drive could be seen from Alpha Centuri; there’s no hiding from the opposition and catching him by surprise.

So both sides know where the other guy is, where he’s going and what course he’s likely to take. If one side doesn’t want to fight they can probably avoid doing so unless the opposition has vastly better delta-V.

If both sides want to scrap then they approach on closing vectors, with the AI performing evasive manoeuvres to stop the enemy’s beam weapons scoring hits at extreme range. At the same time they deploy their defensive AKV’s and fire the first of many salvoes of missiles. The AKV’s boost ahead of the ship to intercept enemy munitions and to ensure that any anti-missile KKM they fire have dispersed enough by the time the main ship comes barrelling through that they don’t mission kill their own side.

The two side’s initial salvoes close on each other and that area of space becomes a maelstrom of high velocity metal, nuclear explosions and x-ray lasers. Anything that survives that ploughs on toward its target. It’s likely that this would be repeated several times as the two ships close from extreme range. Any surviving defensive AKV’s would shift mission profile after deploying their anti-missile defensives and switch to HK mode, hoping to ram the enemy battleship as it comes through.

Any missiles or HK AKV’s that survive interception are now closing on the target which fires up its point defence weapons to take them out before they get to dangerous range. Once again space is filled with lasers, munitions and nuclear detonations. If the battleship’s AI is lucky it gets all the incoming AKV’s and missiles. If not the ship takes hits from nukes and x-ray lasers and if it’s really unlucky a couple of tons of AKV with a combined velocity of tens of kilometres per second. If that happens it’s game over for the battleship as it converts virtually instantaneously from pride of the fleet to expanding ball of plasma.

Assuming that both sides manage to take out all incoming munitions (or survive any hits from those that got through) then they whiz past each other, either slowly if they really want to kill each other or quickly if they just want to do a drive by. As they approach to within a few hundred thousand kilometres they open up with lasers and particle beam weapons that begin knocking chunks off the other side and bathing the interior with ionising radiation (hence the “storm cellar” for the crew).

Shortly thereafter one of them dies.

So it’s likely that the rules of space battles, when we have the technology to make them happen will be:

1. No hiding, you can’t so don’t even try.
2. You’ve only got two options: run or fight. Pick one and make sure it’s the right one because you won’t be able to change your mind.
3. The AI will do the decision making. Almost everything will be automated, the computer will almost always get it right and outcomes will be highly predictable.
4. Combat will be over quickly; either a missile will decide it or a single close pass with beam weapons will see one, or both, of the combatants dead.
5. Beam weapons can only hit moving targets at relatively close ranges because of the problems of light speed lag.
6. Speed is life. Anything that lacks the ability to manoeuvre is dead. Space stations I’m looking at you.
7. Size is life. Planets and large asteroids make good bases because they can have weapon systems and power supplies vastly superior to anything that can be carried on a ship. As a result they can put up enough volume of fire that any vessel that approaches them is dead.
8. You can’t assault a planet until you’ve scrubbed it clean of all defences. Asteroids are good for this – strap on an engine and drop it on the target. You’ll need a lot of rocks though because any self respecting planetary system will know that and will have lots of asteroid defences in place.

Unfortunately it’s not very romantic but that’s the way of the world.

 

[neutrino_cannon]

A nuke isn't going to be that effective in space. No air, no shock wave. The only thing going out is radiant energy in various frequencies and a little debris. The intesity of both will drop off at the inverse square, so the lethal radius of a nuke would be rather small.

Space is big.

Most of the spacecraft will have to be extremely reflective, otherwise the sun will cook them. An early space combat scheme involved paining enemy ships black so that the temperature inside would skyrocket. No air, remember? That convection thing doesn't work quite so well anymore. I agree that stealth will be largely impossible because of this.

As for guided missiles, there will be some aspect of dodge-ability if they bear any resemblance to present anti-ballistic missile weapons. The sensor scans about a one degree cone, that being the only area it could realistically scan given the engagement distances involved. One degree is not very big, even several hundred thousand kilometers away, if you have high enough thrust engines. Besides, only easily intercepted missiles will have lots of fuel for maunvering anyhow.

Rail guns would have severe recoil problems, and you would still have to solve barrell erosion issues. For the power consumption, gauss rifles just aren't worth it.

Conventional cannon, even with liquid propellant, don't have the velocity and would give you away with big flashes of light in any case.

I'm going to say lasers are the most effective weapon. With good enough focusing and aiming, you could hit targets at a great distance with a great degree of accuracy, even if they were moving (lead for c velocity projectiles isn't going to be that hard). As an added bonus, you'll cap the enemies before they can shoot missiles off at you.

I'm not so sure about moving asteroids. Those things are really big. You might just as well take the engines you intended to scoot the rock with and fling them at the planet, which would yield higher kinetic energy anyhow (1/2m*v^2).

 

[Bikewer]

In the Larry Niven/Jerry Pournelle collaboration Footfall, the alients used asteroids, referring to such a weapon as a "foot". (The aliens were highly-evolved pachyderm-type creatures, with a strong herd mentality. Putting one's foot on the fallen enemy was a sign of dominance.)

Heinlein used rocks as weapons too, in The Moon Is A Harsh Mistress. Firing from the Moon using magnetic accellerators.

 

[geni]

A nuke isn't going to be that effective in space. No air, no shock wave. The only thing going out is radiant energy in various frequencies and a little debris. The intesity of both will drop off at the inverse square, so the lethal radius of a nuke would be rather small.

So? you don't trigger the things until they are within cm distance of the target.

 

[Ziggurat]

Either way there won’t be a lot of manoeuvring going on because there is no stealth in space. All (realistic) space craft are easily detectible at long ranges; they’re incredibly hot compared to the background of space and any drive they use is even hotter.

Actually, not true at all. With engines off, a non-manned craft (such as a missile) could get quite cold. And recall that the blackbody emitance is proportional to the absorption, so with a reflective surface, you're not going to be radiating much at all. A cold mirror in space is invisible.

For example the manoeuvring thrusters of a space shuttle in orbit around Earth can be detected from beyond Mars using current technology passive sensors. If that shuttle fires its main engines you can detect them from beyond Pluto. A realistic fusion torch drive could be seen from Alpha Centuri; there’s no hiding from the opposition and catching him by surprise.

Also not true. While surprise is hard to come by, hiding is not. While it may be possible to see the thrust from such a long distance away, actually tracking a trajectory with enough accuracy to intercept at large distances is pretty much impossible. Invisibility at long ranges is entirely possible - they'll pick you up a few times as you do course corrections, but in between they've got nothing. You won't be able to intercept at long distances. Missiles will be going close to as fast as you can make a ship go. If you send something out to intercept, relative velocities will be huge. You won't be able to target an invisible missile with accuracy, so you can only hope to get in the general area, but your relative velocity difference means you can't do anything even once you get there. You can't turn your interceptor around to match the missile, because it won't be able to outrun the missile (fuel requirements guarantee this), you can't hit it with lasers because you'll only have a short time to be in range and lasers won't penetrate reflective surfaces well, and you can't even touch it with anything else.

 

[Ziggurat]

So? you don't trigger the things until they are within cm distance of the target.

Triggering is actually a challenge. Relative velocities are going to be HUGE, and even for a nuclear device, the detonation sequence takes a finite amount of time. Wait a millisecond too long, and your missile has smashed itself against the target without detonating. Detonate a millisecond early, and you're far away enough from the target that the blast force is significantly attenuated (it'll go as 1/r^2). Actually, a millisecond is probably much longer than the critical time scale here. This isn't an inherently unsurmountable problem, but it will be a challenge, and it's likely that you're not guaranteed a good hit with any single nuke.