Interesting Plasma Weapon Concept

[Stark]

I never thought Blake's 7 was any less cool for its invisible beams (not counting the Liberator's guns, which were silly). In fact, even as a ten-year old I knew better, and found that to be simply awesome. Hell, the only reason I kept watching Dr. Who was because B7 was on afterwards.

The B7 handguns were pretty awesome: I think it was helped by the awful film they used, so the muzzle flash created a big pink spot. Gunfights had clouds of smoke and totally dead guys everywhere, not silly beams of childishness.

[Connor MacLeod]

I think its just a brain bug really. I mean we see the EFFECTs of bullets (firing and impact) often in movies, but we obviously don't see the bullet itself and they have no urge to paint it in. (Though in some cases like 'Master and commander" I think they did kinda put it in, ora t least I thoughy ou could sorta see cannonballs and not just the effects.)

Ironically it also occurs to me in alot of sci fi energy weapons tend to leave very neat small wounds (especially Star Wars), whereas in movies at least you get a lil blood and gore from a bullet.

The glowy bolts can kinda break "suspending disbelief", ,but the neat kill-holes do it alot more for me (though it can be explained.)

And did anyone else have a flashback to the Furry Conflict guy with this "plasma weapon" theory?

[Sea Skimmer]

I think its just a brain bug really. I mean we see the EFFECTs of bullets (firing and impact) often in movies, but we obviously don't see the bullet itself and they have no urge to paint it in. (Though in some cases like 'Master and commander" I think they did kinda put it in, ora t least I thoughy ou could sorta see cannonballs and not just the effects.)

I always liked The Dark of the Sun, for firing off real mortars when filming, with the camera easily catching the bombs flying through the air as you can do with the naked eye. Can't do that shit in Hollywood!

Conventional guns also have a usually ignored advantage of bring able to fire radically different ammo for different situations. Generally at best sci fi energy weapons have different power settings, which hardly allows for the difference between say a smoke shell and a DPICM shell fired from a 155mm howitzer.

[Darth Wong]

I think its just a brain bug really. I mean we see the EFFECTs of bullets (firing and impact) often in movies, but we obviously don't see the bullet itself and they have no urge to paint it in. (Though in some cases like 'Master and commander" I think they did kinda put it in, ora t least I thoughy ou could sorta see cannonballs and not just the effects.)

I always liked The Dark of the Sun, for firing off real mortars when filming, with the camera easily catching the bombs flying through the air as you can do with the naked eye. Can't do that shit in Hollywood!

Conventional guns also have a usually ignored advantage of bring able to fire radically different ammo for different situations. Generally at best sci fi energy weapons have different power settings, which hardly allows for the difference between say a smoke shell and a DPICM shell fired from a 155mm howitzer.

The ability to use ballistic indirect fire is also a significant advantage.

[Connor MacLeod]

Conventional guns also have a usually ignored advantage of bring able to fire radically different ammo for different situations. Generally at best sci fi energy weapons have different power settings, which hardly allows for the difference between say a smoke shell and a DPICM shell fired from a 155mm howitzer.

And indirect fire, ,as Mike says. I think that pretty much qualifies as a brain bug too (the idea that "newer technology is always better") that you hear. Railguns and lasers and plasma sound and look futuristic, so they must be automatically all around better. (When that's not neccesarily the case.)

I often see similar logic that in every cases a nuke must be better than conventional explosives (even though its easier to make things like shaped charges or fragmentation weapons from conventional explosives - nukes are a bit too indiscriminate mainly in that regard.)

[Sea Skimmer]

Aye, and I’ve yet to hear of a sci fi energy beam with a capability to vary the muzzle velocity of whatever it happens to fire; though I suppose some obscure book might have that. Without that ability, you’ll have an awful hard time effectively shooting indirectly, even if your energy beam is in fact affected by gravity. The need for varying velocity and high angle fire; is why virtually all tube artillery in modern militaries takes the form of howitzers or mortars. True guns are now rare as artillery.

Course, this wouldn’t matter in space fighting, but even the ability to fire different types of ammo sure would be useful, both for ship to ship action and surface bombardment.

[Connor MacLeod]

Aye, and I’ve yet to hear of a sci fi energy beam with a capability to vary the muzzle velocity of whatever it happens to fire; though I suppose some obscure book might have that. Without that ability, you’ll have an awful hard time effectively shooting indirectly, even if your energy beam is in fact affected by gravity. The need for varying velocity and high angle fire; is why virtually all tube artillery in modern militaries takes the form of howitzers or mortars. True guns are now rare.

I don't really see how you could do that with lasers without some sort of mirror or forcec field redirection (which is goign to require separate components.) It might make sense by using drones, but that's about it.
And even then, I'm not betting on it having the effective range of a projectile weapon (IE mortar or howitzer)

PArticle beams probably would be pointless. There's gonna be enough problems with the atmosphere screwing with the beam - redirecting it is bound to make that worse (and even if it works, its going to have to affect the cohesion/velocity of the beam to SOME extent, which reducese its effectiveness.)

In theory a railgun COULD vary its velocity, and you probably could design it to carry/fire munitions, but it probably wouldn't be a whole lot better/different than a conventional explosive weapon. Just a bit faster.

Course, this wouldn’t matter in space fighting, but even the ability to fire different types of ammo sure would be useful, both for ship to ship action and surface bombardment.

True. Thougn in orbital bombardment you'll still face some disadvantages with beam weapons compared to projectile (atmospheric interferencee with the beam)

[Ford Prefect]

True. Thougn in orbital bombardment you'll still face some disadvantages with beam weapons compared to projectile (atmospheric interferencee with the beam)

Depending on the wavelength of laser, you may not be able to use them for orbital bombardment at all (as I recall, below 200 nanometres, it's worthless). I'm not so sure about particle beams, though ultimately one would probably be best using kinetic munitions. As has been suggested, you can have different types of munition ... plus there's lots to be said about the simplicity of dropping a can on someone's head at a million miles per hour.

[Ariphaos]

Depending on the wavelength of laser, you may not be able to use them for orbital bombardment at all (as I recall, below 200 nanometres, it's worthless). I'm not so sure about particle beams, though ultimately one would probably be best using kinetic munitions. As has been suggested, you can have different types of munition ... plus there's lots to be said about the simplicity of dropping a can on someone's head at a million miles per hour.

200 nm is the boundary for near-ultraviolet, where atmospheres will be opaque to it. It's a rather bad idea to use low-wavelength light in general due to Rayleigh scattering - especially if you're talking about crossing an atmosphere with it. The military's current research is to mode-lock two (or possibly more?) light beams, which creates a beat effect in the wave pattern, giving higher peak energy. The result is then pulsed - you fire in a series of quick, successive bursts.

The idea is to vaporize more material at once, over a shorter period of time, while allowing the resulting plasma to disperse, which would otherwise shield the target area.

It's purpose in-atmosphere strikes me as being highly specialized, and more defensive then offensive, however.

[Winston Blake]

More to the point, those horrific effects would not be produced by the plasma weapon. Gases are lousy heat conductors compared to liquids and solids, and if the pellet bursts and sprays out a lot of super-heated gas, you won't get spray effects at any appreciable distance from the pellet.

How about just shooting blobs of liquid tungsten at 5000 degrees centigrade? I make that about 230 KJ of thermal energy in a 100g projectile, plus the trivial 125J of kinetic energy you'd get from shooting it at 50 m/s out of a grenade launcher style weapon. It should glow very brightly and splatter pretty nicely.

Make it a comparatively cheap, conventional mini-shell filled with TNT and you get 418 kJ. If it's a tracer it'd be just as visually impressive as a blaster, aside from the fact that its speed would probably make it hard to see on film.

[Sea Skimmer]

In theory a railgun COULD vary its velocity, and you probably could design it to carry/fire munitions, but it probably wouldn't be a whole lot better/different than a conventional explosive weapon. Just a bit faster.

The main advantage of a railgun is you don’t need to haul around a pile of rather heavy, bulky and quite dangerous propellant charges. Explosive shells are far less likely to cause a magazine explosion then propellant is.

[Eleventh Century Remnant]

In the role-playing game 'Traveller', the ultimate battlefield artillery were Meson cannons.
Basically, the meson stream passes through matter interacting very weakly, making it possible (with proper targeting) to draw lines of fire through inconvenient things like the horizon, and they decay explosively at the end of their lives- which were prolonged, and the range set, by accelerating them to precisely controlled relativistic speed.

Meson cannon were also used in ship to ship, ideally detonating inside the target vessel; planetary defence meson cannon, because of their (supposed) terrain piercing abilities, were often buried miles underground.

Aside from the difficulty of turning something needing that much precision into a field- reliable weapon, is there any shred of scientific credibility to this at all or is it another one for the dustbin of bad ideas?

[Ford Prefect]

The main advantage of a railgun is you don’t need to haul around a pile of rather heavy, bulky and quite dangerous propellant charges. Explosive shells are far less likely to cause a magazine explosion then propellant is.

Go figure. Isn't there also a limitation to how much velocity you could realistically get out of chemical propellant? Presumably you could just keep putting more and more in, but that's going to get pretty silly pretty fast.

[Ariphaos]

Go figure. Isn't there also a limitation to how much velocity you could realistically get out of chemical propellant? Presumably you could just keep putting more and more in, but that's going to get pretty silly pretty fast.

Yes, but, at least in our atmosphere, that's also competitive with the speeds at which the physical round will begin to ablate.

[Darth Wong]

In theory a railgun COULD vary its velocity, and you probably could design it to carry/fire munitions, but it probably wouldn't be a whole lot better/different than a conventional explosive weapon. Just a bit faster.

The main advantage of a railgun is you don’t need to haul around a pile of rather heavy, bulky and quite dangerous propellant charges. Explosive shells are far less likely to cause a magazine explosion then propellant is.

Mind you, you now need to haul around a large power source, and most sci-fi high-density power sources seem to be rather volatile.

[Ariphaos]

Mind you, you now need to haul around a large power source, and most sci-fi high-density power sources seem to be rather volatile.

The year before I attended college, one of the senior projects was to produce a functioning railgun. 18 industrial-grade batteries were being used, and one of the assistants (how someone so stupid...) hooked one of them up backwards. Something like six or twelve of the batteries were completely ruined, and the thing wouldn't even fire afterwards, apparently overheating the magnet in the process.

Were it not for that incident I'd probably praise their simplicity.

[Darth Wong]

Mind you, you now need to haul around a large power source, and most sci-fi high-density power sources seem to be rather volatile.

The year before I attended college, one of the senior projects was to produce a functioning railgun. 18 industrial-grade batteries were being used, and one of the assistants (how someone so stupid...) hooked one of them up backwards. Something like six or twelve of the batteries were completely ruined, and the thing wouldn't even fire afterwards, apparently overheating the magnet in the process.

Were it not for that incident I'd probably praise their simplicity.

Ever seen an industrial battery depot for forklift trucks? It's unreal; you don't want to get anywhere near it. Certain technologies only seem really clean when you don't see the back-end.

[Lord of the Abyss]

I think its just a brain bug really. I mean we see the EFFECTs of bullets (firing and impact) often in movies, but we obviously don't see the bullet itself and they have no urge to paint it in. (Though in some cases like 'Master and commander" I think they did kinda put it in, ora t least I thoughy ou could sorta see cannonballs and not just the effects.)

I recall reading some years ago that you could see the cannonballs coming with the older low velocity cannon; I don't know if that was true in Master and Commander's era.

[Cykeisme]

When you're firing from outside an atmosphere, the free destruction you get out of the dropped object's gravitational potential energy is a big bonus.. at least until your power generation and weapon energy output gets to the point where the free GPE of a dropped object becomes negligible in comparison, then I guess a directed energy weapon might be better.

And indirect fire, ,as Mike says. I think that pretty much qualifies as a brain bug too (the idea that "newer technology is always better") that you hear. Railguns and lasers and plasma sound and look futuristic, so they must be automatically all around better. (When that's not neccesarily the case.)

Regarding indirect fire, is it feasible to have a railgun that allows you to vary the muzzle velocity?

Depending on the type of projectile (whether it relies entirely on kinetic energy to do damage, and what kind of mass we're talking about) I think this could be a pretty good way to achieve indirect fire capability.

I think its just a brain bug really. I mean we see the EFFECTs of bullets (firing and impact) often in movies, but we obviously don't see the bullet itself and they have no urge to paint it in. (Though in some cases like 'Master and commander" I think they did kinda put it in, ora t least I thoughy ou could sorta see cannonballs and not just the effects.)

I recall reading some years ago that you could see the cannonballs coming with the older low velocity cannon; I don't know if that was true in Master and Commander's era.

I don't know any either way, but it's worth stating that the visibility of a projectile is not affected just by its velocity, but also by its size. A cannonball is pretty huge compared to a small arms round.

[Starglider]

What is it with this obsession with railguns? Any reasonably advanced sci-fi powers is going to be using coilguns instead. Railgun rail wear problems are still going to be severe with any currently conceivable materials technology (we might get it down from rail replacement every ten rounds to rail replacement every hundred rounds) and that's with a relatively limited muzzle velocity. Coilguns have no wear problems and will become much lighter if we develop room-temperate superconductors (which is a lot more likely than magic rail materials).

Regarding indirect fire, is it feasible to have a railgun that allows you to vary the muzzle velocity?

Yes, this is a straightforward upgrade to the control electronics.

[Ariphaos]

What is it with this obsession with railguns? Any reasonably advanced sci-fi powers is going to be using coilguns instead. Railgun rail wear problems are still going to be severe with any currently conceivable materials technology (we might get it down from rail replacement every ten rounds to rail replacement every hundred rounds) and that's with a relatively limited muzzle velocity. Coilguns have no wear problems and will become much lighter if we develop room-temperate superconductors (which is a lot more likely than magic rail materials).

Because, despite my above post, they are not significantly more complex than a conventional gun. Needing to replace any single part is simply a matter of replacing said part. Adjusting the 'muzzle velocity' is simply a matter of controlling the amount of juice you're giving it. Railgun with 30% efficiency means you plug that into the basic equations and you're good to go. No timing issues involved - if you know the maximal output of your gun, relative firing rate, have a few spare parts (being able to fire a hundred times before replacing the rails would mimick reloading from the Crusader design).

A coil/Gauss gun, on the other hand, needs very exact timing that could even be sensitive to changes in atmospheric content. Changing the exit velocity is not simply a matter of changing the wattage applied - you must also change the timing. You can't fire an effective Gauss gun without a computer. When replacing a broken part of a coilgun, any given coil also needs to be hooked up to the timing again, in the correct order, in the correct direction. More idiotproofing is required.

[Zixinus]

Say I have a magnetic thrower (either coil or rail), and I have the brilliant idea of heating up the projectile. I have no idea how it could be done effectively and fast enough, but lets say we can do it.

Question is, is it worth it? Say a projectile firing iron needles? Perhaps with putting wolfram/tungsten (why does it have two names?) in the middle?

Also, do rail guns or coil guns have less recoil then a conventional firearm?

[AMX]

Also, do rail guns or coil guns have less recoil then a conventional firearm?

Depends.
Conventional guns can vent or redirect propellant gasses rearwards, lowering or even completely eliminating recoil; but that has certain drawbacks, obviously.

If such methods are not used, or only to a limited extent, EM weapons have less recoil.

[Dooey Jo]

I think its just a brain bug really. I mean we see the EFFECTs of bullets (firing and impact) often in movies, but we obviously don't see the bullet itself and they have no urge to paint it in.

Unless it's Transporter, where they made every bullet a tracer for some reason...

[Winter]

Hello, everyone -- first post here. I'm Winter, lead story dev for UFO:AI. Adrian Magnus posted a link to this thread on the UFO:AI forums, and after reading the whole thing, I figured I'd drop in.

I'll begin by admitting that I don't know a hell of a lot about plasma physics. Nor do I have much free time for research, especially for a freebie side project (much as I love the game). When I do get into it, I simply don't have the background to understand most of the reference material that's available. Other times we're forced to play a bit loose with realism due to engine limitations or the quirkiness of a particular 3d model.

Even so, while I may not always achieve it, I do try to ground every bit of material in reality as much as I can. This would be easier if I had some knowledgeable people I could count on to give me some pointers and exchange/critique ideas. So, good posters of this forum, I'd like to invite those of you who think your brains are up to the challenge to join the project and keep us writers on the plausibility track.

We may not be able to satisfy every detail to the exacting specifications of reality, due to flaws both technical and personal, but we try. And I think that's important in this day of cartoon games that throw physics and plausibility out completely because it makes development slightly more difficult.

Anyone who's interested, please post here to let me know.

Regards,
Winter