Weapons in space

[Dangerous_Beans]

bomb pumped lasers are useful, because you can send the laser off on a different path to the missile. so the missile can look like it will miss by 10,000km, then detonate and blast off a bunch of lasers. having a bunch of bomb pumped lasers mixed with kinetic kill missiles means your opponent has to shoot down every one, not just the ones that are going to hit them.

same logic applies to Casaba-Howitzers.

[magnemoe]

Lasers aren't really very effective at that. There have been some demonstrations of chemical lasers that are able to defeat artillery rockets and mortars on a ballistic trajectory, but these are attacks at an angle to that trajectory (ie: they don;t have to kill the incoming projectile by acting on its tiny frontal cross-section). There's no laser that can defeat an incoming missile head on. Guns and other missiles however are able to do this, and for a tiny fraction of the size and weight.

I don't think you're likely to see point defences of any kind on space vehicles though. Similar to aircraft, stealth, speed and countermeasures are going to be more effective on a vehicle that has to be lightweight.

Artillery shells and mortars tend to come pretty much straight towards the target at the last 1/3 of the trajectory, they are also small, 12- 15.5 cm in diameter and half an meter long.

Add to the fun that they have thick metal casings and is pretty insensitive to heat and shock, has to survive being shot out of an cannon in the first place. The most sensitive part is the fuse who is in the front.

[magnemoe]

bomb pumped lasers are useful, because you can send the laser off on a different path to the missile. so the missile can look like it will miss by 10,000km, then detonate and blast off a bunch of lasers. having a bunch of bomb pumped lasers mixed with kinetic kill missiles means your opponent has to shoot down every one, not just the ones that are going to hit them.

same logic applies to Casaba-Howitzers.

Yes, it might also make sense as an sort of mine, put an cluster of them to intercept the estimated path of the enemy, now drop them from the missile while its under trust and it will be very hard to predict their trajectory, they would be passive and it should be possible to give them an low radar and IR signature. Best countermeasure would be constant and variable trust.

[magnemoe]

One of the powerful weapon: ISV Venture Star orbital laser gun for propelling the interstellar photon sail. Imagine your ship getting beamed by multi petawatt CW laser...

And if we have a source of huge thrust (Orion drive) than you could pretty much ignore the mass problem anyway (1300 metric tons)

Yes, Niven used them in both the beginning of the Man-Kziin war and Moth in the gods eye.

And yes, an reaction drive is not an effective long range weapon Niven was mistaken here, however it would make an good close in weapon system. an missile to catch up with something with an orion or fusion engine can not just trust towards it back.

[Dangerous_Beans]

Best countermeasure would be constant and variable trust.

i'm not sure about that; the mine could spin around pretty quickly in the last second before it detonates, and at the distances lasers will be effective at light is pretty close to instantaneous, so there is no dodging time. so varied acceleration wouldn't help.

the best countermeasure would be to shoot them, but for that you have to know that they are a threat. the other option is to just not be nearby. both are things that you're unlikely to be doing if you just think that its a missile that missed or debris.

[magnemoe]

i'm not sure about that; the mine could spin around pretty quickly in the last second before it detonates, and at the distances lasers will be effective at light is pretty close to instantaneous, so there is no dodging time. so varied acceleration wouldn't help.

the best countermeasure would be to shoot them, but for that you have to know that they are a threat. the other option is to just not be nearby. both are things that you're unlikely to be doing if you just think that its a missile that missed or debris.

Not so much to avoid getting hit yes more so they don't know where to place the mines. if you burn, drift and brake its easy to predict your path, if you do lots of course corrections this become impossible. until you reach the target.

And as you say here you need to clean it and this can be plenty of work, more so at these mines will be pretty hard to find. just an IR signature from the low power internal system and absorbed sunlight.

[Seret]

Space is probably a bit big to make area-denial weapons much use. You'd have to deploy a pretty immense number of them to occupy any useful sort of volume. You don't really get choke points in space that can be usefully mined.

[TheSaint]

I think that space warfare will resemble a carrier battle more than anything else. When the ships engage they'll launch a fleet of missiles armed with nuclear-pumped lasers, and a fleet of unmanned interceptors designed to stop the enemy's missiles before they reach their targets. The main battle will be a furball of missiles and interceptors between the opposing fleets. The manned ships will have point defense lasers to act as a last ditch defense against enemy missiles should they make it through the interceptors.

Evasive maneuvers could be effective, depending on the range to the target. Even though a laser travels at the speed of light, your opponent's knowledge of your location travels at the speed of light as well. At long ranges, the attacker will have to extrapolate your location when the beam will reach you based on your last known speed and heading. If you are constantly evading, that extrapolation may not be accurate.

Mines may not be very useful, since as others have pointed out space is really big and there are no natural chokepoints. However, placing a lot of mines in orbit around a planet that you know the enemy will want to orbit could be useful, if you can reduce their EM signatures so that they are invisible. If not, they'll be sitting ducks for interceptors.

[Comrade Jenkens]

At the moment missiles are the only effective weapon that could be utilised in space. However both railguns and laser weaponry is in prototype testing with working examples of both. Assuming that you could launch the bulky power generators and capacitors, both of these may also be feasible. Lasers could also be used for point defence, shooting down incoming missiles.

[SargeRho]

Missiles are crap in space, tbh. Lasers are the best weapon we have for space.

[Motokid600]

MAC cannons baby.

[ZedNova]

Phase cannons and modified Sidewinders should do the trick.

[TheSaint]

At the moment missiles are the only effective weapon that could be utilised in space. However both railguns and laser weaponry is in prototype testing with working examples of both. Assuming that you could launch the bulky power generators and capacitors, both of these may also be feasible. Lasers could also be used for point defence, shooting down incoming missiles.

Chemical lasers would do away with the power generation apparatus. They derive their power from a chemical reaction rather than electrical input. The only downside is that your laser has an ammunition count.

You could also use explosive power generators, which use an explosive propellant to generate a very brief, very large pulse of electric current. Same drawback as the chemical lasers though.

Edited September 12, 2013 by TheSaint

[Kryten]

The apparatus needed for that 'chemical reaction' is huge, it'd be very unlikely to offer a weight advantage when you'd likely need a large generator of some kind for a warship anyway. As an example, the laser generating apparatus in the 747 airborne laser takes up almost the entire plane.

[TheSaint]

The apparatus needed for that 'chemical reaction' is huge, it'd be very unlikely to offer a weight advantage when you'd likely need a large generator of some kind for a warship anyway. As an example, the laser generating apparatus in the 747 airborne laser takes up almost the entire plane.

Engineering problem. The COIL laser that they fit in the YAL-1 wouldn't fit in a warehouse when they first developed it back in the 70s. Given time, money, and motivation, it will become smaller and lighter.

It always amazes me how pessimistic the folks on this board are about the advancement of technology, especially since we are fans of a spaceflight simulator. Fifty years ago computers filled an entire room and cost hundreds of millions of dollars. Now you probably walk around with one in your pocket that is more powerful and can download information wirelessly from anywhere in the world. Come on, guys, we live in the future!

[Kryten]

Engineering problem.

And the engineers have spoken. The DoD now doesn't have a single development program for chemical lasers, they're all electrical. Electrical lasers are able to see exactly the kind of progress you're talking about, but chemical lasers have hit more fundamental constraints in terms of reaction rates and conditions.

[Dangerous_Beans]

Missiles are crap in space, tbh. Lasers are the best weapon we have for space.

why is that?

lasers have a range dictated by their focusing optics, and require bulky electrical systems that produce a lot of waste heat. missiles have a "range" dictated by their delta V, and just require some sort of rack to haul them around.

[TheSaint]

And the engineers have spoken. The DoD now doesn't have a single development program for chemical lasers, they're all electrical. Electrical lasers are able to see exactly the kind of progress you're talking about, but chemical lasers have hit more fundamental constraints in terms of reaction rates and conditions.

For now. There are still folks developing chemical lasers. Most medical lasers are chemical lasers, so there is still a lot of money in making them smaller, lighter, and cheaper. With advancements in chemistry and material engineering, they could be big in weaponry a couple decades down the road. I wouldn't count them out just yet.

But yeah, a free-electron laser would have a lot of advantages as well. And you could power it with an EPG, which would give you a compact, light power source, albeit a limited one.

Missiles are crap in space, tbh. Lasers are the best weapon we have for space.

I think that, like most weapon systems, combined arms will be the key. Throwing all of your weight towards lasers or missiles would be the equivalent of equipping your aircraft with only guns or missiles. (Remember how well the USAF did in Vietnam with the missile-only F-4s? They gave that idea up quick.) Or equipping your naval ships with only guns or missiles, that is a bad idea as well. Each has a job to do, and together they can do it better. The whole is more than the sum of its parts. I think that conventional missiles with high-explosive or kinetic energy warheads would be at a severe disadvantage, but even they may find a niche in a point defense role.

[Seret]

why is that?

lasers have a range dictated by their focusing optics, and require bulky electrical systems that produce a lot of waste heat. missiles have a "range" dictated by their delta V, and just require some sort of rack to haul them around.

You'd need tracking and fire control for missiles, and a few other bits and pieces such as coolant if required. Not a biggy though, you'd just need to interface with the navigation system. Aircraft tend to have a combined navigation and weapons system, so fire control is done with the same sensors and electronics as navigation.

Missiles being chemically powered have the great advantages of being light, compact and stable. You get a lot of kills stowed in a small light package. Lasers with enough power to come anywhere near the firepower of guns and missiles are enormous, so really aren't viable for spacecraft. Maybe one day that will change, but I wouldn't hold your breath. I would fully expect to see aircraft (and therefore any potential armed spacecraft) to keep packing guns and missiles for the next several decades at least. There's not really anything on the horizon that looks like it'll outperform them, and the military are understandably quite conservative about their weapons technology. Reliability is fundamental, and past performance counts for a lot.