tag:blogger.com,1999:blog-7494544263897150929.post551161474771244568..comments2024-03-28T00:36:19.403-07:00Comments on Rocketpunk Manifesto: Battle of the Spherical War Cows: Purple v GreenRickhttp://www.blogger.com/profile/16932015378213238346noreply@blogger.comBlogger105125tag:blogger.com,1999:blog-7494544263897150929.post-44929345247622159372023-03-08T19:06:38.927-08:002023-03-08T19:06:38.927-08:00Michael: "does anybody know how that waste he...Michael: "does anybody know how that waste heat would compare with a similarly powered laser?"<br /><br />Well, this answer may not be precise since it's heavily influenced by the CoaDE simulator but, here it goes anyway.<br /><br />While there has been a lot of talk in this blog about multi& megawatts lasers i have to notice that solid state lasers (Wich are the most likely to be weaponized any time soon, i think they already did) are very, VERY, inefficient; so that you might have an idea it goes from 4%-10%, and they get less efficient the more power you pump into it and thus, have to be built larger so they don't melt). So, when you have a 20-30 MW laser you'll be getting around 5% of that energy in the laser beam and 95% as waste heat.<br /><br />Now regarding railguns it gets better, you should be able to get around 35%-50% efficiency (same power input) for sub kilogram ammunition. So you end with grams size ammunition traveling at 10-50 km/s. It scales up badly as well (regarding projectile mass). So, if you have a 1kg projectile it drops to around 20%. But it's rate of fire is great (10- 30 slugs/second) as long as you have active rail cooling, a good capacitor bank and solve the rail erosion problem. <br /><br />Coilguns (or Gauss guns) are also very efficient they get to 80%-90%. This would make it look like the best weapon of choice, but it's not that simple. They are very heavy and require high mass (several kilograms)ferrous projectiles, so their muzzle velocity is lower, around 10km/s. Also their rate of fire isn't great.<br />That sums it up. I know the answer got with years of delay but hope it's useful.<br /><br />DanielAnonymoushttps://www.blogger.com/profile/16838266341393800177noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-54958730676770396512021-07-01T11:59:16.146-07:002021-07-01T11:59:16.146-07:00Rick, I have a shameful confession to make:
*I do...Rick, I have a shameful confession to make:<br /><br />*I do not believe in Laserstars.*<br /><br />(Say ten Hail Mary's and twelve Our Fathers.)<br /><br />I'm sure at some point there will be great big Motherwatt superlasers shining across the Solar System, more likely as propulsion or power rather than as weapons. But IMO, that day is not the Plausible Mid-Future.<br /><br />In my lifetime I've seen laser weapons become a battlefield reality... in small numbers under very limited circumstances. There's just too many real-world issues in the field. Thermal stress and distortion and reliability are the limiting factors. The hype around DEWs is like the speed of light, you can approach it with great difficulty and effort but you can never catch up to it.<br /><br />Laser weapons may indeed be deployed in a populated PMF Solar System. But in practice they may prove underwhelming compared to the way they're talked up here. Effective *maximum* range best guess might be planetary orbital distances, probably a lot less, and they won't get near that point anytime soon. Lasers will probably be very valuable as point defense and sensor dazzle, but not as Big Friggin' Guns. That is one with the torch drive and the stealth ship.<br /><br />I hope I'm wrong, of course, it would be RuleOfCool to have a ravening death ray. But I just can't foresee it living up to its optimism.Saint Michaelnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-84048035742103465202019-12-13T10:21:26.695-08:002019-12-13T10:21:26.695-08:00How are you going to armor the missile guidance op...How are you going to armor the missile guidance optics? It seems that if the laser can burn out the guidance sensor, then even a torch drive missile turns into a harmless unguided rocket. It also seems that you can't armor an IR sensor from being hit with an IR laser. E Shttps://www.blogger.com/profile/18171044768882320109noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-23274616572397230212018-05-19T04:45:57.356-07:002018-05-19T04:45:57.356-07:00The correct answer is "whether SpaceBus or La...The correct answer is "whether SpaceBus or LaserCon has the most friends on the appropriations committee". Most military purchases have minimal relationship to tactical utility. Most military equipment is never used. A lot of it doesn't work as intended if it is, but is still used because LaserBus has friends on the Hill. Militaries are always going to be strapped with a bunch of garbage, plus a few weapons which will work almost by accident.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-43656298617848451922014-01-26T13:43:55.631-08:002014-01-26T13:43:55.631-08:00Hi TDA:
I don't thing your 'terror weapon...Hi TDA:<br /><br />I don't thing your 'terror weapon' would do much.<br /><br />These rocks would come in at a shallow angle like the <a href="http://en.wikipedia.org/wiki/Chelyabinsk_meteor%22" rel="nofollow">Chelyabinsk meteor</a>, but at 8 km/s rather than 18.6 km/s, so would have less than a quarter the kinetic energy per unit mass. The Chelyabinsk meteor had an estimated mass of 12,000–13,000 metric tonnes, but it's hard to see your 'rocks with engines' massing more than a few tonnes each. So I would expect each rock to damage a few city blocks, but come in at random & so probably land in open ocean, desert tundra etc.<br /><br />To get those rocks to do some damage to the enemy you want them to come in near vertically on some target of value to the enemy. How about have a bunch of them orbiting the enemy planet at roughly lunar distance & programmed to deorbit at specific targets if they don't receive the 'no go' signal every few days?Jim Baergnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-58341286709833048082012-02-20T20:15:09.717-08:002012-02-20T20:15:09.717-08:00I finally re-read the other comments, and I've...I finally re-read the other comments, and I've got a couple of other points.<br /><br />If a laserstar can burn down all the kinetics coming at it, that's great. But the laser is outputting lots of heat in the process. The term "heat advantage" (or something like it) has been thrown around: at this point, the kinetic ship will definitely have that heat advantage, especially if there's a kind of "lancer" setup where most of the initial velocity comes from the velocity of the ship, not a (powered) launcher. That means the kinetic ship (or its laser-armed buddies) can outlast the enemy solely on heat absorption.<br /><br />A laserstar can make more precise attacks on a ground target, but if the people you're supposed to be deterring (or blind fate) manage to damage that laser (i.e. the optics), the threat disappears. You could, however, send a command ship (which could be laser-armed) with a swarm of smaller "rocks with engines"--not literal rocks, but inert masses that have rockets, fuel, and guidance but nothing else, then set them on a decaying orbit with a command from the manned ship boosting them up every so often. Destroy that ship, no command gets sent, and you have a bunch of dumb bombs falling over the place. Not very precise, but a wonderful terror weapon. Sort of the space equivalent of a "dead-man switch."<br /><br />Probably a lancer will be best for delivery of a kinetic penetrator. That will reduce the mass of fuel and engines, maybe just to s couple of solid boosters for final approach. Most of the evasive maneuvers will be handled on the part of the bus.<br /><br />Again, I feel certain it will be a "combined-arms" environment, but a kinetic shell is much more damage-resistant than a laser: if all else fails, you "cross their T" and shove the thing out an airlock.<br /><br />http://www.projectrho.com/rocket/spacegunconvent.php#id--Kinetic_Kill_Weapons--Equations<br />Go on down to the example--that's the most productive use of cat litter I've ever seen :)<br /><br />-TDAAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-32222576486873383622012-02-20T14:19:04.751-08:002012-02-20T14:19:04.751-08:00I kinda skipped the other comments due to time res...I kinda skipped the other comments due to time restraints, so if any of these are repeat arguments, I apologize.<br /><br />I favor kinetics for this reason:<br />Imagine you're walking down a dark hallway and all of a sudden someone reaches out and jabs you in the eyes. That's a laser strike.<br />Now imagine you're going through that hallway and someone pulls the lanyard on a cannon pointed at you. You know, one of those 19th century monstrosities that fire a solid 12-pound iron ball. At point-blank range. That's a kinetic strike.<br /><br />A laser can mission-kill a target by blinding its sensors, destroying its lasers, or burning through to some critical component.<br /><br />A kinetic-kill shell can mission-kill a target by obliterating the thing. And a starship (at least a "hard" SF starship) will generally be flimsy enough that it can't withstand a solid mass impacting at high velocity. Like one dropped right in front of it.<br /><br />And it'll be harder for the laser to take them down if fifteen, twenty seconds out the thing fragments into 50 or so individual penetrators.<br /><br />Not to mention they're harder to dodge.<br /><br />-TDAAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-30590674242743504482011-01-17T13:45:02.494-08:002011-01-17T13:45:02.494-08:00>And, finally, what would you call a combat spa...>And, finally, what would you call a combat spacecraft the size of a Laserstar/Kineticstar but armed with rocket driven morters tipped with bomb-pumped X-ray laers and/or nuclear shaped charges?<br /><br />Nukestars?<br /><br />Speaking of which: I know the cost would go up a lot, but bomb-pumped lasers on the front would mean a lot less distance to close before being able to wreck the defending 'star, meaning less of them need to be launched. Maybe if the lasing could work with a shaped charge, then a small warhead and laser right behind the nose armor.<br /><br />Couple thoughts on kinetic design:<br /><br />How expensive would it be to put a small, tunable laser on the front of every bus? With a bright light being shined on the enemy's sensors, hopefully targeting would be a little more difficult. Plus, if you either find the wavelength your enemy uses or randomly go through the spectrum, then the enemies point defense optics get a little toasty.<br /><br />Of course, if you use disposable, one-shot buses, might as well turn them into penetration-aids. Leave the missiles as semi-dumb hunks of metal (maybe a small warhead on the front to make a hole in any whipple shielding) while the bus tries to confuse / kill any defending sensor or laser..Danielhttps://www.blogger.com/profile/03150243938040644775noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-71120162428523332122010-10-05T06:19:54.671-07:002010-10-05T06:19:54.671-07:00In my universe, quite the opposite. Kinetics are w...In my universe, quite the opposite. Kinetics are weak to lasers unless used in massive amounts, in each shot. Since every ship capable of fighting uses a laser, with laserships just the warships with the biggest baddest lasers, Kinetic craft are expensive and rare, while lasers commonplace.<br /><br />Check my scenarios in ground warfare. The pirates use a kinetic craft, while cargo ships can be refitted with lasers very quickly for combat.Turbo10khttps://www.blogger.com/profile/03052157965564640932noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-45664077230964312502010-10-05T06:19:48.014-07:002010-10-05T06:19:48.014-07:00In my universe, quite the opposite. Kinetics are w...In my universe, quite the opposite. Kinetics are weak to lasers unless used in massive amounts, in each shot. Since every ship capable of fighting uses a laser, with laserships just the warships with the biggest baddest lasers, Kinetic craft are expensive and rare, while lasers commonplace.<br /><br />Check my scenarios in ground warfare. The pirates use a kinetic craft, while cargo ships can be refitted with lasers very quickly for combat.Turbo10khttps://www.blogger.com/profile/03052157965564640932noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-9589598732807235942010-08-24T18:55:33.670-07:002010-08-24T18:55:33.670-07:00Yes. With a sort of meta strategic implication. Le...Yes. With a sort of meta strategic implication. Less militarized societies or communities may tend to favor kinetics as requiring less defense investment - just the actual kinetics, with a 'civil reserve' of ordinary spacecraft doing the pre-release positioning.Rickhttps://www.blogger.com/profile/16932015378213238346noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-61363732183678304352010-08-24T15:46:49.474-07:002010-08-24T15:46:49.474-07:00I haven't finished reading through the comment...I haven't finished reading through the comments but I'm left with the impression of a rock-scissors-paper type battlefield.<br /><br />The best weapon to use against a laserless craft (e.g. a KEW bus) would be a single high delta V (long range) guided missile.<br /><br />But a single guided missile/torpedo would be useless against a laser armed opponent.<br /><br />The best weapon to use against a laser armed craft would be the KEW weapons bus (swamp the defenses).<br /><br />The best weapon to use against a missile / torpedo boat would be the laser ship (if it had enough delta V to catch them).<br /><br />Of course there's no reason that each of these craft can't carry a couple of auxiliary missiles or smaller weapons buses!<br /><br />BUT a ship with a laser as the primary weapon will always be a warship first and everything else would be secondary.<br /><br />The other weapons can simply be loaded into anything with cargo hard points (interior and exterior) and some extra delta V.<br /><br />JimAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-41455793736015280102010-03-30T06:04:06.216-07:002010-03-30T06:04:06.216-07:00I did some caluclations on a recoverable bus, and ...I did some caluclations on a recoverable bus, and the numbers aren't as bad as they look. If I assume the same tech as given here, and wish to throw the projectiles at 10 km/s, the ship might break down as follows:<br />50% kenetics<br />10.8% recoverable ship<br />28.4% launch fuel<br />10.8% return fuel<br /><br />The actual delta-v is 30 km/s for the recoverable part, while still being able to launch 50% of the launch mass in kenetics.Byronhttps://www.blogger.com/profile/07778896782683765138noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-46450548778391609332010-03-09T15:07:16.280-08:002010-03-09T15:07:16.280-08:00I would appreciate more visual materials, to make ...I would appreciate more visual materials, to make your blog more attractive, but your writing style really compensates it. But there is always place for improvementAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-17607870391604534872009-09-10T21:23:32.598-07:002009-09-10T21:23:32.598-07:00One general difference between laser and kinetic c...One general difference between laser and kinetic components is that there is no particular reason for big kinetics platforms (except to be big and impressive). They can just as well be deployed from multiple smaller bus vehicles, allowing some more flexibility.<br /><br />But I'd expect laser stars to be big, with the largest practical power supply and weapon installation, because one maximum laser can outrange two smaller ones of equal combined power, whereas kinetics are simply additive.<br /><br />On the other hand, there's reason for kinetic buses to be fast, whereas speed does not add to the direct fighting power of a laser star.<br /><br />So a constellation deploying both weapons might have one big laser star, a few smaller laser craft, and a number of kinetics buses, medium sized or smaller.Rickhttps://www.blogger.com/profile/16932015378213238346noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-65260286873630648332009-09-10T19:55:20.108-07:002009-09-10T19:55:20.108-07:00I would rather have constellations be a main ship ...I would rather have constellations be a main ship (Laserstar of Kineticstar) as a command ship for a small flotilla of smaller drones, themselves armed with an assortment of weapons and/or ECM. They can deploy large radar-reflective sails or overly large radiators to mask the thermal signature of your Laserstar. They jamming won't do all that much but might make it just confusing enough you have to add a few seconds for targeting computers to sort through the chaff. Use the kineticdrones to launch some projectiles in the mix to make things confusing to the other side, force them to overheat their lasers, stress their target acquisition software, and play merry hell with the enemy crew's stress levels. the laserdrones can be used as CIWS for the main vessel, or sweep the enemy ships from more angles than they can deal with.<br /><br />An assault force would combine Laser constellations and Kinetic constellations, coming in from different angles. If you are the attacker and the defender has to protect a specific area, they will be faced with multi-pronged attacks. Because of the implied distances between your constellations, each main ship would be crewed to have command-level decision making in rapid comm range of the flotilla. Since none of these maneuvers can be stealthy, the enemy knows what may be happening. This is the other reason you want command-level decision-making in each constellations: if this is all posturing, there's the chance of someone on one side overreacting. If one captain jumps the gun, you don't necessarily want the whole fleet to commit.<br /><br />"It was an adder!"Jean-Remyhttps://www.blogger.com/profile/07186948442919090289noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-85289384713285229492009-09-10T19:16:42.792-07:002009-09-10T19:16:42.792-07:00Jim, you might want to use a rail/coilgun to launc...Jim, you might want to use a rail/coilgun to launch an NSWR propeled kinetic mini-bus; I, for one, wouldn't want a barely controled fission reaction going off in my face :)<br /><br />Also, on a slightly different track, the minimum number and make up of a Combat Constellation would be...what? three Laserstars, a Kineticstar, and a Commandstar? or three Kineticstars, one Laserstar, and a Commandstar? Or skip the Commandstar and do three Warstars (smaller, combined arms warships)?<br /><br />And, finally, what would you call a combat spacecraft the size of a Laserstar/Kineticstar but armed with rocket driven morters tipped with bomb-pumped X-ray laers and/or nuclear shaped charges?<br />Just some thoughts...<br /><br />FerrellAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-70948382335754867382009-09-10T13:57:48.040-07:002009-09-10T13:57:48.040-07:00More in the seminar than I can comment on!
My un...More in the seminar than I can comment on! <br /><br />My understanding of railguns is that they are limited to a few km/s max. Any faster and you melt the rails, not good. Coilguns may be more complex, but they give higher speed and less waste heat. Without getting into SF magitech, upthread Michael outlined a coilgun about 100 m long and shooting at 10 km/s, with acceleration comparable to a rifle round.<br /><br />Pretty much keel mounted, but I will argue that primary directed energy weapons will generally be keel mounted, because you can mount a longer range weapon that way. And with long range, and given limited prolonged acceleration, you generally have time to turn and fire. <br /><br />Particle beams are Nasty. And they don't sound extraordinarily effective, so their use against humans might be the equivalent of gas warfare. Depending on hard it is to armor/harden electronics, they don't sound very useful against robotic ships.<br /><br />At 10,000 km, not long range in space, even a beam spread of 0.01 percent means a beam diameter of 1 km and a tiny fraction of the beam energy hitting the target (unless it is humongous).Rickhttps://www.blogger.com/profile/16932015378213238346noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-14654056974632342272009-09-10T09:04:28.266-07:002009-09-10T09:04:28.266-07:00Sabersonic: In a power limited situation (such as ...Sabersonic: In a power limited situation (such as the 1 GW reactor we have been talking about) a big (perhaps primary) advantage of the coilgun is that it can convert most of that power into kinetic power of its projectiles rather than heat power dissipated in the plasma arc. With 1 GW available, a coilgun might be able to deliver 900 to 950 MW of power in the form of the motion of the projectiles, while a railgun might only give you 200 MW. <br /><br />There's also the issue that the electric arc erodes the rail, so the rail will need to be replaced frequently. In some railgun designs, the rail is part of the ammunition, and replaced after every shot.<br /><br />Jean Remy: A coilgun is simply an electric motor unrolled into a line. As a linear electric motor, it no more needs superconductors than a rotary electric motor. Copper will work fine. Since the main inefficiency of an electric motor is due to electrical resistance, superconductors will increase the efficiency - but well designed electric motors already reach 90% to 95% efficiency.<br /><br />I suppose, just for the sake of completeness, I will mention that there are two "flavors" of coilgun. The equivalent of a synchronous electric motor requires the projectile to be made out of ferrous metal, and the switching magnets attract the ferrous metal in the projectile. The equivalent of an asynchronous electric motor uses projectiles without ferrous metal, and pushes/pulls on the projectile by inducing eddy currents in the conductors for the magnetic field to push against.<br /><br />As far as particle beams, a Z-pinch isn't really involved (you only get a Z-pinch when you have a current that is screened from its own electric charge by an ambient material). A good linear accelerator is all you need. particle beams do not self focus in space. Their main range limitation is the random thermal motion of the particles in the beam - the beam may start out a micron wide, but if the particles have an average thermal speed of 0.01 c and the beam is moving at 0.5 c, you get the beam opening in a 50:1 cone (this example is rather unrealistic for illustrative purposes - 0.01 c is not uncommon for the thermal motion in particle beams, but the speed of the particle bunches is likely to be more like 0.99 c to 0.999 c and this introduces relativistic effects into the opening angle. I can go into more details on how to calculate this if others are interested).<br /><br />A particle beam does not do kinetic damage, not in the sense of a kinetic round. The momentum of a particle beam is about the same as that of a laser of the same energy, and the beam particles do not act as a continuous media to disrupt the target. Rather, each particle punches through individually, losing energy by ionizing the atoms it passes by and occasionally smacking into a nucleus and shattering it into more high speed particles. This does heat the target, but heats it deeply rather than on the surface. It also produces all the effects of ionizing radiation (which it is), such as health effects and amorphizing the crystal structure of delicate electronic components.<br /><br />A particle beam can be deflected by a magnetic field. You would use a strong magnet for the turret. You would also neutralize the beam just before it left by injecting a co-propagating beam of oppositely charged particles. The primary beam will probably be protons, and it will be neutralized with electrons, giving you a beam of hydrogen plasma.<br /><br />There is no intrinsic reason a particle beam needs to be inefficient. With high Q superconducting accelerating cavities, you could in principle put most of your energy into the kinetic energy of the particles. The main inefficiencies would then the the refrigeration you need to keep the superconductors cool. In principle, a free electron laser could have very nearly the same efficiency since it is essentially a particle beam that converts its particle beam energy into light energy, so it may be that particle beams and lasers have the same efficiency.<br /><br />LukeLukehttps://www.blogger.com/profile/09617890536562434320noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-31852426000560122702009-09-10T08:37:53.614-07:002009-09-10T08:37:53.614-07:00Jean Remy
"I think if we tart throwing in tor...Jean Remy<br />"I think if we tart throwing in torchdrive the kinetic buses will fall by the wayside."<br /><br />The NSWR ( http://en.wikipedia.org/wiki/Nuclear_salt-water_rocket ) sounds like it would scale down far enough to put in a missile that could track a target that is also using a NSWR to maneuver.<br /><br />Re: rail guns vs. coil guns.<br /><br />This technology: http://en.wikipedia.org/wiki/Launch_loop could be adapted to shooting 'cannonballs' at an enemy. BTW If I understand it correctly the waste heat would go into the launching loop & not into mass that is launched, so the 'cannonball' would not be enormously conspicuous in the infrared.Jim Baergnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-24068824826578966592009-09-10T07:44:28.799-07:002009-09-10T07:44:28.799-07:00This comment has been removed by the author.Jean-Remyhttps://www.blogger.com/profile/07186948442919090289noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-86615365778387156832009-09-10T05:55:51.210-07:002009-09-10T05:55:51.210-07:00A minor point, but IC fusion doesn't necessari...A minor point, but IC fusion doesn't necessarily require a laser. If the society has managed modest levels of antimatter production, you could do antimatter initiated fusion. <br /><br />It seems likely that heat will by a problem with a rail gun, but does anybody know how that waste heat would compare with a similarly powered laser? <br /><br />To weigh in on the particle beams issue: It seems to me that a particle cannon could have similar range and response time as a laser, but has fundamentally different doctrinal issues. Lasers seem to be the weapon to use when you need to project useful power, ie, power that you can use without causing unnecessary damage and without irking allies. Discreet, effective force projection. Particle beams, on the other hand, are the weapons you use when you want people to know that whoever stands against you will be dead, no questions asked. They get one chance to surrender, and if they don't take that chance, they die quickly from the initial damage or die slowly from a heavy radiation dose.<br /><br />The United States would use lasers.<br />The Roman Empire would use particle beams. <br /><br />MichaelAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-11562386172903754422009-09-09T23:05:33.858-07:002009-09-09T23:05:33.858-07:00Saber: "However I have to ask this question: ...Saber: "However I have to ask this question: Would a self-propelled Kinetic round be a better choice over an Electromagneticly Launched Round from a dedicated coilgun either spinal or mounted upon a turret?"<br /><br />I think one of the points we've been discussing is to actually put a self-propelled kinetic <i>in</i> a rail/coilgun to give it that initial kick.<br /><br />Coilgun v railgun (VERY simplified)<br /><br />A railgun is a Jacob's ladder on steroids. It's of a (relatively) simple construction as you basically have two conductive rails, you create a plasma arc with the projectile, and you shoot the whole thing downrange. They require a LOT of power and create a LOT of waste heat. We already know how much of a problem waste heat is in space.<br /><br />A coilgun is a Maglev train, and similarly more complex in construction. The projectile is in suspension inside magnetic coils, and the polarity in the coils is changed very fast, attracting and repulsing the projectile along. They require supraconductors which either need to be cryogenically cooled, or require the invention of "warm" supraconductors. They generate less heat but as far less "brute force" approach have a lower acceleration.<br /><br />Purple v Green... v Orange?<br /><br />Orange Option being particle cannons. If the technology to create z-pinched near-light-speed particle cannon exists, they might have greater reach than a laser(self focusing), will not require a vulnerable mirror, will inflict kinetic damage added to thermal damage, and have a time to target close enough to a laser that the difference would be insignificant (especially compared to a kinetic bus). The disadvantages are probably the need to mount a large accelerator, they can't be turreted since deflecting the beam robs it of most of their delicious kinetic energy, requiring the entire ship to swing, and they might be deflected with magnetic shields. Their energy requirements are probably a little off the wall compared to lasers and missiles.Jean-Remyhttps://www.blogger.com/profile/07186948442919090289noreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-13009294621086256262009-09-09T22:22:16.239-07:002009-09-09T22:22:16.239-07:00Correct me if I'm wrong, but I have read/heard...Correct me if I'm wrong, but I have read/heard somewhere that for a coilgun to have a range equal to that of a railgun then the coilgun's lenght would have to be about two times or more the barrel length of the railgun. However, the chief advantage of a coilgun over a railgun would be a higher Rate of Fire which is perfect for the high volume saturated fire needed to at least keep a target craft busy while it either the attacker or its buddies maneuver themselves towards that target craft's weaker sides.<br /><br />However I have to ask this question: Would a self-propelled Kinetic round be a better choice over an Electromagneticly Launched Round from a dedicated coilgun either spinal or mounted upon a turret?<br /><br />I ask because from what I can gather, the chief factor in the cost of the Kinetic Round would be the drive motor that accelerates the mass towards a target and be able to have a high enough DeltaV budget to not only reach the target, but to also make course adjustments to lower its chances of being zapped out of the sky and keep on track with the target craft. <br /><br />But what if that round only needed enough DeltaV to make course corrections and keep on target while some other external force gave the projectile the velocity needed to cross the distance between the shooter and the target? A Coilgun-launched Kinetic Round does offer that possibility as shown by the following visual examples at 5:57 to 6:02 and 7:44 to 7:58 in the following video clip: <br /><br />http://www.youtube.com/watch?gl=JP&hl=ja&v=aZ_kGr0EK3M<br /><br />However I am unsure if it is a viable weapon system layout for orbital space combat, let alone deep space. Then I got this little brain fart: If diffusion of a laser decreases its damage potential of the focal point upon the target and the distance between the laser and the target having its own diffusing properties, then would it not be prudent to launch a Kinetic Round/Missile/whatever towards the enemy craft that deploys a Laser Diffusion Cloud that is closer to the lasing ship than the lased ship?<br /><br />And since a majority of the combat spacecraft classes are potentially being designed with an armored face plate as evident in the previous replies, would it be too presumptuous of myself to think that a majority of the offensive weapon systems would utilize a mechanized system similar to the Disappearing Gun as this article describes:<br /><br />http://en.wikipedia.org/wiki/Disappearing_gun<br /><br />And one other thing:<br /><br />"In spite of the practical elegance of Michael's layered shutters, for cinematic purposes there is nothing like the order 'Unshutter main mirror!' ... external view, in silence, as the armored shutter slides slowly open to reveal a big laser mirror."<br /><br />Well there's nothing really stopping one in creating that little visualization. Granted, it doesn't make mention to the inner shutters but then again, how much detail do the reader/audience really need?<br /><br />- SabersonicAnonymousnoreply@blogger.comtag:blogger.com,1999:blog-7494544263897150929.post-27854811949678018562009-09-09T20:54:45.223-07:002009-09-09T20:54:45.223-07:00Railguns and coilguns have very different technica...Railguns and coilguns have very different technical details, but in SF the terms are used pretty interchangeably. As I did in my last post, when I wrote 'railgun' even though I'm actually imagining a coilgun. <br /><br />I think people say 'railgun' because it sends its payload at express highball speed. :-)Rickhttps://www.blogger.com/profile/16932015378213238346noreply@blogger.com