posted
At the risk of making me more geeky I wish to start a little think tank to come up with plausible design ideas for a Starship based on "realistic" 21st cutting edge technology and not the crack that alot of scifi writers tend to smoke.
The premise is this: Assuming we had a viable means of FTL travel between point A to point B or at least Star A -> Star B and vice versa "conveniently" how would one design a starship with warfare in mind, assuming we only had the theoretical 21st century technologies we currently possess.
To start:
quote: A warship is a ship that is built and primarily intended for combat . Warships are usually built in a completely different way than merchant ships. As well as being armed, warships are designed to withstand damage and are usually faster and more maneuverable than merchant ships. Unlike a merchant ship, a warship typically only carries weapons, ammunition and supplies for its own crew (rather than merchant cargo). Warships usually belong to a navy, though they have sometimes been operated by individuals or companies.
quote: A starship is a theoretical spacecraft designed for traveling between the stars, as opposed to a vehicle designed for orbital spaceflight or interplanetary travel.
--Wikipedia.
Disclaimer: I hold no engineering degree or DEC, I am operating purely upon speculation and popular science.
To determine how to design a star-warship it is best to travel back in time and consider what the requirements for a conventional ocean going warship.
The first requirement, the most important one, seaworthiness.
quote: In 1976, St.Denis[1] suggested that there are four principle terms that are needed to describe a seakeeping performance. These are:
* Mission : What the ship is intended to accomplish. The role of the ship while at sea. * Environment : The conditions the ship is intended to operate in. This can be described as Sea state, Wind Speed, Geographic Region or some combination thereof. * Ship Responses : The response of the ship to the environmental conditions. The Responses are a function of the Environment and the Vessel Characteristics. * Seakeeping Performance Criteria : What the established limits are for the Ship Responses. These are based on the [Ship motions]] and the accelerations experienced. The criteria are often based on comfort criteria (sea sickness : Motion Sickness Index - MSI), performance based values such as involuntary speed reduction or observable phenomena such as bow immersion.
So on oceans a ship/warship needs to be able to float. So for a spaceship it needs to be spaceworthy as such. What is being spaceworthy? Is it just like taking a submarine and hauling it to space? Nyt.
To make something spaceworthy obviously it A) needs to be hardened against cosmic radiation, B) nuclear radiation as nukes are probably a good safe bet as a standard front line or at least oftenly used in space strategic weapon. C) it needs to be sufficiently armored to protect itself from space debre.
I think that largely covers space worthiness as once something can survive the horrors of space its pretty damned space worthy.
Now that we have determined space worthy using 21st century technology how could we make a warship using 21st century technology? Lets start with something tangibly related to spaceworthiness.
Propulsion:
Obviously a ship needs to move on its own power, compressed air/controlled burst rockets are be used to maneuver for boarding/docking operations, but what about interplanetary movement?
So far I think the most advances have been made in Ion propulsion, so I suspect it'll take the lead although sometime ago I heard of some kind of thereotical form of propulsion being closely looked at by the airforce and NASA so who knows.
We're looking at two different things though, the ability to get from Earth to strategic parts of the solar system within a comfortable amount of time, can ion propulsion or that newfangled one if someone knows what is is allow a ship roughly the size of the IJN Yamato reach pluto is less then a couple of days? I think that is whats needed to be aimed for.
Armour: beyond minimal amount of armor needed to withstand space we'll need armor plate to defend against enemy armament. Now, lets look at armour in terms of the top of the line ocean combatant ships of WWII/Cold War.
The Battleship: The Yamato, possibly the most powerful baddy of the seven seas until Okinawa had around 410 mm of armoured plate, designed not only to withstand shelling on its side, but also should a shell fall under th waterline and hit below the water line.
The most powerful armament until the cruise missile were shells, 18.1" shells to be precise, so battleships needed to be able to withstand the shelling of other battleships. So our starship by extension also needs to be able to withstand the same amount of force it deals. "Take it as well as dish it out" as a minimal requirement.
Personally I would suggest 2-3 Meters of Titanium armoured plate as a starting point, can't speculate much more now until we know more about what we're up against, but a few thoughts.
Because space is a 3 dimensional vacuum there is no way to justify only hardening certain "sides" of the ship, so I'ld expect a rather boxy angled surface kind of warship and hopefully itll angle the right way when taking fire, but as to how effective sloping armour will be in space I do not know, we might be better with a more squared shape.
Upgradibility, it should be possible to semi-easily remove the armor and replace it with better/lighter/stronger armor as technology improves.
Survivability in reentry? I don't know, but I think it should be seriously considered, but for now I think it optional.
Weaponry:
Missiles are a must, unless AEGIS/MAGIC SHIELD/SKY WATCH technology has advanced to the point that missiles are obsolete and unusable we'll still have missiles delivering conventional and nuclear payloads to targets.
A) They're fast. B) They cheap. C) they can be powerful. D) Accurate.
Next, Magneticaly propelled rounds, lets look at Coil guns and rail guns.
Railguns I think are closer to practical use so I'll speak of them, the ability to fire a round at extremely fast speed at a probable really far range if large enough should be fairly powerful kinetic weapon, can it pierce through meters of solid metal? I don't know, but I suspect that railguns could very well be the mainstay weapon of a starship.
Now the question is, how feasible is space superiority fighters/bombers in space? I do not know, but the possibility is there, it is undoubtable all large and medium ships should have the ability to launch/recieve/service shuttle craft of various types though.
Next, what the heck is it with all these different elaborate designs for ships, all the different classes of ships sailing the oceans LOOK ALIKE, the only exception being the carrier but take off the flight deck and you still have the same chassie.
So in space I think that most likely for ease of production all the ship classes will look largely alike differing in A) size, B) armament, C) logistics capability.
Beyond that their shapes should be largely the same.
posted
One of the primary difficulties, I would imagine, is that space is so large. How difficult is it for any two ships to actually come within combat range of one another? Just FINDING the other ship would be very difficult, then maneuvering toward them would be very hard if the other ship moves at all.
In real-life terms, unless we're talking about fantastically advanced systems in the far future, reaction mass might be a very limiting factor. How much fuel can one ship expend changing course constantly to get to the other ship?
I don't imagine a lot of deep-space battles, because there's no point fighting in the middle of nowhere. All battles would take place around a strategic resource: a planet, asteroid, starbase, or the like. In such a case, the available resources and mass of the defending base would be so great that a huge number of ships would need to attack to have a chance of surviving and doing significant damage.
That's my first thought on the matter.
Posts: 3950 | Registered: Mar 2006
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Blayne Bradley
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I looked alot of startegy stuff inregards to planetary battles and all one needs to do is neutron bomb a colony and the task in an extreme case of taking is is moot. Other then that I'ld imagine with the brigade revolution in doctrines weld see alot more mobile wars on planets and combined arms.
Beyond that though space is largely empty so near strategic points unless theres alot of jamming going on RADAR/LADAR should be able to locate other ships so finding people isn the problem.
Getting close you may have a point but eventually like say near a planet ships will need to stand and fight, running away is all well and good but it doesnt win battles.
We can make a few fairly safe assumptions.
Pitched battles between flotilas in space can and will happen.
Finding enemy ships is possibly and possibly easy with the exception of heavy jamming.
The distances fought at are probably within the same range as todays hi tech naval engagements.
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posted
The fighting would probably be happening around planetary bodies, so I don't really see a problem with finding other space ships. Deep space battles are unlikely, because even if you could find someone with magic sensors that detect someone light years away, who'd actually be out there? Fighting will happen in and around planets, moons, etc. But that leaves plenty of room for actual space battles.
As for armor, you've got it a bit wrong there I think Blayne, but it depends. If we're building battleships in space, I'm going to assume we have some sort of advanced way of getting stuff from the planet into orbit, and that we'll be buiding ships in orbital space docks, and not on the surface. So what does that mean? Weight won't matter. Which means we aren't limited to armor like Titanium, we can use much better more defensible armor like the stuff on an Abrams, which is insanely heavy, but it's also far stronger and resistant to hits. I'd expect several feet of that, double hulled and mixed with a kevlar type webbing in between layers, to take a lot of punishment before a puncture. A Kevlar like material will be fantastic at stopping regular projectiles, but you'll still need thick armor to blunt explosives or what I imagine will be the space equivilant of a HEAT round. Space battles I think will be a mix of naval, tank, and air fights.
Weapons? I think you've nailed most of it. Rail guns will be extremely helpful in space, and though I think missiles will have a limited role (I belive point defense in space will probably make a lot of missiles hard to justify, unless we create stealth missiles). But I don't see why we wouldn't have lasers. I imagine lasers would work far better in space actually. There's no atmosphere, which means we'd have a much smaller problem with blooming, where the beam breaks up and loses focus, and cooling would have to be a lot easier since all you have to do is vent the laser to space and it'll cool instantly.
I imagine fighters would be indispensible in space. Giant space ships just make giant targets. It's naval battleships compared to naval carriers. The battleships would be able to do a lot of damage, and would take out a lot of fighters, but I think in the end fighters are very easily mass produced, and could be produced on planet, instead of in expensive space docks, and then launched into space or carried into space. In other words, slap an engine and a cockpit onto a mobile weapons platform with a lot of smaller stablizers to move around, and you've got very mobile weapons platforms. But I wonder if they'll be human piloted or remote controlled. Part of me suspects remote control, but I wonder if humans will ever get over their love affair with flying (Personally I'm pretty nostalgic about the idea myself, and I don't even like flying). I think fighters will be an indispensible part of a battlecarrier group. I suspect a space fleet would be similar to an old school naval fleet. There will be fleet tenders to repair and carry supplies, stealthy scout ships, smaller attack corvettes for light duty and patrol, heavy battlecarriers for the punching and carrying of fighters, and medium sized destroyers to serve as weapons platforms and perhaps more importantly, as point defense for the larger ships to take out incoming nukes before they hit.
I imagine mass drivers would be considered too. I've seen some work recently on real life tractor beams done on a nanoscale. That makes me think controlling resources in space might be a realistic endeavor in the near future if we discover some sort of FTL drive. And it makes me think that mass drivers would be a potent weapon that'd be hard to defend against unless all ships were very small, very light, and highly maneuverable. I guess the weapons will dictate the composition of the ships.
Posts: 21898 | Registered: Nov 2004
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Blayne Bradley
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posted
Remote controlled/robot fighters/bombers will never in my mind become common place, why? Jamming for the former, reliability and pronness to hacking to the latter. Humans will always be more politically reliable then a robot.
Its like the human vs Mobile Doll argument in Gundam Wing.
The thign is Lytharn about armour is that while that stuff is BETTER is it CHEAPER? How easy it is to massproduce good quality Abrams armor in the range of several dozen thousand tonnes to armour a Battleship in space per ship?
Also while I have no doubt there will be point defence but while if its good enough to stop a missile why cant it also be good versus fighter-bombers? A universe where ftr-bombers are effective is also a universe where missiles are effecitve and vice versa. Missiles travel faster and can maneuevr in ways I am certain g forces would not allow a fighter to except in cases of its fighter bombers vs installations and smaller craft.
Lasers I distrust because unless you can get lasers hot enough to melt through the best possible composite amrour we can make, I doubt their effective ness past point defence, I haven't seen alot of effective progress in the range of Halo-esqe Plasma cannons able to burn through 6 meters of Titanium with ease within the next say 20-30 years.
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posted
I have a question. I haven't taken AP physics in a few years, and haven't really been interested in science since, so forgive my ignorance. Why wouldn't the heat from the lasers dissipate in space before it reaches the target?
Posts: 2705 | Registered: Sep 2006
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Blayne Bradley
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Because there's no friction? Space is a vacuum. Also were not talking about pen lasers, the lasers used would either be A) point defence lasers aimed at taking down incoming missiles like recently testing on a Boering 747 or would be large cannons used to pierce and melt away meters thick composite armour, which would require significantly sized lasers and significant powe routput making dispersion of the laser unlikely.
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It's an interesting moral argument about mobile dolls vs. human pilots. I liked that angle from Gundam Wing (one of my favorite animes). And I hadn't considered jamming when talking about remote controlled fighters, so I guess humans would be necessary.
I really didn't take cost into account because I figured if we're building space battlecarriers, we probably have a crapload of money. Besides, Titanium is ridiculously expensive and for that matter isn't exactly plentiful. How do you propose to build multiple ships composed of "several dozen thousands tons" of the stuff? I'm honestly not sure what goes into producing Abrams armor. Not many are. It's still a classified process that I believe only the Brits and we have.
The thing about missiles is that, as of yet, they don't maneuver. They go from point A to point B. You're talking about a missile with some sort of AI that'd juke and try to dodge a point defense system, the same way a human pilot would, otherwise all you have to do is track a missile and hit it with some sort of Phalanx like point defense weapon. I think that'd make missiles incredibly expensive per shot, and wouldn't necessarily eliminate their use, but they'd be more of a niche weapon, or maybe a last ditch weapon, than the primary rail guns or laser.
On lasers, that's because we're still working on shrinking the technology to fit it on smaller weapons. I've seen a laser burn through a foot of iron armor, and that was from a small laser in a test lab. In a battlecruiser there'd be a hell of a lot more energy to use, and a lot more space to fit the actual weapon. The weapon could run the entire length of the ship if needed. They could scale the thing UP instead of the direction we're headed now, which is to make it smaller while increasing the yield. The type of thing you're talking about wouldn't be viable for 50-100 years anyway, by which time I expect laser technology would've more than caught up.
Besides, you said yourself that the best composite armor we can make is too expensive, which means they only have to burn through titanium. But I wonder how feasible multiple meters of armor is going to be over a massive space ship. We'd have to master asteroid mining to come up with the resources you're talking about, or we'd strip the planet bare just building a single ship.
Posts: 21898 | Registered: Nov 2004
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I agree that missiles are where it's at, weaponry wise. They're going to be pretty sophisticated things, but like Lyrhawn, I'm assuming that cost really isn't too much of an issue.
I'm not so sure really heavy armor would be worth it anyway. It'd just make your fuel costs jump. I suspect that in space warfare, early detection, location, and overwhelming firepower are going to trump most armor and maneuverability.
That armor's going to have to be mighty thick to stop the nukes the other guy is slinging at you. Granted, nukes might not be viable depending on the resource being fought over. Defense would mostly be missile counter-measures, I'd imagine.
Lasers, currently, would be more useful to paint an opposing starship for a missile than anything else. And most guns would be worthless. Easily avoidable at long range, and you'd have to get way inside missile range.
quote: The record-setting beam measures 20 billion trillion watts per square centimeter. It contains 300 terawatts of power. That’s 300 times the capacity of the entire U.S. electricity grid. The laser beam's power is concentrated to a 1.3-micron speck about 100th the diameter of a human hair. A human hair is about 100 microns wide.
I think lasers could work. I don't really see a need for warships. To defend against invaders we could probably just have planet based weapons.
Posts: 1287 | Registered: Apr 2006
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posted
I think it's Starworld by Harry Harrison that has a pretty good description of a battle using rail guns and missiles, ie not your average whizz-bang laser fest.
Pretty good descriptions of the usefulness of cold, unpowered lumps of iron against "space" defences.
(Not 100% sure about the book ref until I can check it at home - watch this space)
Posts: 892 | Registered: Oct 2006
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posted
Some of this discussion heavily relies upon the assumptions that one brings to the table in the first place.
The viability of armour is heavily reliant on the characteristics of FTL travel in the particular universe. For example, in a universe where FTL travel is difficult to use or constrained with hyperspace gates or the like then armour becomes useful. In a universe where FTL is extremely fast, simple, and small to implement, the possibility of FTL projectiles would render physical armour nearly irrelevant. (we know that inertia F = mv much slower than the speed of light but that breaks down and becomes screwy at near light speed, who knows what happens to mass at FTL speeds, which leads back to our assumptions)
Of course then it also depends on what assumptions you have about FTL sensors and the ability to intercept said projectiles and etc. Lots of assumptions have to be resolved.
Posts: 7593 | Registered: Sep 2006
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Blayne Bradley
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quote:Originally posted by Juxtapose: Or orbital stations.
Eventually either us as a Unified government will have colonies or the superpower blocs of the future will have colonies, either way a military presence in the form of warships will be needed. For very much he same reasons we need them today, why not simply use long range torpeedo launchers and mines to defend our coast? Becuase we need the ability to project force beyond our borders and that is why we will need ships.
I think it is a reasonable assumption that resources are not a problem, if we are putting our efforts into spaceships then we probably have the resources to sustain it.
Also, a modern aircraft carrier is around 50-90,000 tonnes of displacement. And we have fielded dozens of them as well as hundreds of smaller ships. I don't think Earth is so bare of resources to prevent us from armouring our ships from earths resources itself.
And missiles can maneuevr, look no farther then the Topol-M and the Dengfeng-31A ICBM's.
The ability to send a payload close to c, or faster then c as a weapon I think has been explored in sci-fi but were talking about warships in general, and I think I still answer this point to an extent as to why we cant simply sit on our bums behind orbital MAC stations, power projection, secure transportation of troops etc.
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quote:The Battleship: The Yamato, possibly the most powerful baddy of the seven seas until Okinawa had around 410 mm of armoured plate, designed not only to withstand shelling on its side, but also should a shell fall under th waterline and hit below the water line.
The Yamato has already been made into the most powerful spaceship. All we need is a wave motion drive and we're good to go.
We already have the cool theme song. Posts: 26071 | Registered: Oct 2003
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posted
Pretty certain that, by the time we're dealing with space weapons platforms, we're going to be talking about lasers, rail and coil guns. At 3500 m/s, a projectile has about as much kinetic energy as the chemical energy of an explosive of similar mass. Scale that up, and you're getting the same energy as a nuclear device of the same mass, with the added bonus that your projectile has no electrical components that can be jammed, and is going far too fast to be targeted very well, plus, you'd have to totally destroy the projectile in order to prevent it from damaging your ship.
As far as armor, you can go one of either two ways. Thick enough armor to stop your opponents weapons, at the cost of manueverability. (Mass, not weight, matters for how rapidly you can change your direction). Or no armor whatsoever for high manueverability. Manueverability must be greater then the targetting/flight time of your opponents weapons. With the weapons that we'll likely be using in space, flight speed of weapons will be some significant fraction of the speed of light. If we're using computerized targetting/firing mechanisms, then I don't think manuerverability will end up "beating" armor.
And by armor, I suppose I might end up not meaning thick layers of metal. Certain crystals or ceramics are probably better defence against lasers.
Posts: 4112 | Registered: May 2001
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Assuming that we are dealing with a gravity free environment, where there is no "up" or "down" (read your Ender) then the only way to make sure that you show the smallest available profile from which ever way you are attacked, is to be in the form of a sphere.
Take the central control of the ship, and place it too in 0-g. That whole center room can virtually face any direction you wish, since you will mostly be using enhanced displays and screens, not windows. There will be (is now) no reason to put your command and control in the most vulnerable positions so they can see what's going on. Instead they will be buried in the safest center of the ship.
Posts: 11895 | Registered: Apr 2002
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posted
Try reading Out of the Silent Planet by C.S. Lewis sometime. He gives quite a portrait of life on a spherical vessel.
Posts: 292 | Registered: Jun 2006
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quote:Assuming that we are dealing with a gravity free environment, where there is no "up" or "down" (read your Ender) then the only way to make sure that you show the smallest available profile from which ever way you are attacked, is to be in the form of a sphere.
But that keeps you from having a smaller profile to orient toward your enemy.
Posts: 26071 | Registered: Oct 2003
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posted
Jebus cripes. You guys are talking fantasy, not even science fiction. And certainly not "potential space battle craft using only modern technology".
According to modern physics FTL likely doesn't, and can't exist. In anyway. Even wormholes though cool theory, are likely practically impossible.
Travel in space using current technology is limited to ballistic orbital trajectories. Any time you're going anywhere in space you're in some kind of orbital trajectory. And even with the best of theoretical modern propulsion course correction to avoid fire would be hard to impossible.
Launch vehicles to orbit are extraordinarily expensive. Even the best the launch vehicles of today -- even theoretical ones -- are prohibitively expensive. We're talking thousands of dollars per kilogram launch costs.
And finally cooling in the vacuum of space works through black-body radiation. It is a very slow process that works through natural heat radiation. If it didn't work that way the Apollo 13 astronauts would have frozen instantly when they had to turn off the LEM heaters as the LEM had nothing more than a thin layer of aluminum to protect them. So cooling in space is rather problematic (as is evidenced by cooling system on the ISS, which really only has to dump the heat given to it by the sun into space and requires a fairly extensive cooling system).
So I have to go to take a test on UML (*snore*) but when I get I'll do some speculation on what might actually be vaguely possible with modern technology and how it might actually work.
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Blayne Bradley
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posted
Spheres do not make sense for space combat, there still needs to be a side for your engines, and also you still need to have a land surface efficient shape so that you can place your guns.
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Blayne Bradley
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quote:Originally posted by Alcon: Jebus cripes. You guys are talking fantasy, not even science fiction. And certainly not "potential space battle craft using only modern technology".
According to modern physics FTL likely doesn't, and can't exist. In anyway. Even wormholes though cool theory, are likely practically impossible.
Travel in space using current technology is limited to ballistic orbital trajectories. Any time you're going anywhere in space you're in some kind of orbital trajectory. And even with the best of theoretical modern propulsion course correction to avoid fire would be hard to impossible.
Launch vehicles to orbit are extraordinarily expensive. Even the best the launch vehicles of today -- even theoretical ones -- are prohibitively expensive. We're talking thousands of dollars per kilogram launch costs.
And finally cooling in the vacuum of space works through black-body radiation. It is a very slow process that works through natural heat radiation. If it didn't work that way the Apollo 13 astronauts would have frozen instantly when they had to turn off the LEM heaters as the LEM had nothing more than a thin layer of aluminum to protect them. So cooling in space is rather problematic (as is evidenced by cooling system on the ISS, which really only has to dump the heat given to it by the sun into space and requires a fairly extensive cooling system).
So I have to go to take a test on UML (*snore*) but when I get I'll do some speculation on what might actually be vaguely possible with modern technology and how it might actually work.
FTL travel is not utter fantasy it IS science fiction is well grounded in thereotical physics, see Alcubierre Drive, and there is quite a bit of recently released theoretically work being done by NASA that implies that FTL IS possible.
Also coilguns/railguns can be used to launch heavy payloads into orbit.
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Ok, so 21st century. I think that means we will be seeing battles for control of Earth orbits, the purpose being to support your ground troops by having spy satellites over enemy territory and preventing him from doing the same to you. Later in the century it's just possible we could see battles for control of mineral-rich asteroids, but I think it will be a lot cheaper to just find your own asteroid, they're hardly scarce, so I don't think it very likely.
So the 'spaceships', then, are likely to be satellites, or conceivably a manned space-capable fighter, able to dip into atmosphere or climb out of it. The objective is to kill enemy spy satellites and protect your own. I think nukes are not likely to be used, firstly because EMP knows no flag, and second because nukes in low Earth orbit are likely to make trigger fingers itchy in any number of nuclear powers. Nukes are definitely a weapon of last resort, here, and if you're that desperate, why not hit the troops invading you?
That leaves lasers, missiles with chemical warheads, and just plain rocks. The two first can be fired from Earth stations as well as from orbit.
I think no practical amount of armour will protect a satellite going at orbital speeds from a rock in its path. We can therefore largely ignore armour. The defense against rocks is to be able to detect them and maneuver out of their way, or push them out of yours with, say, a machine gun.
A thing to consider here is that the best way to defend your satellites might be to just build them cheap and launch hundreds at a time, and not care very much if you lose one. The countermeasure would be to interfere with launch capacity, hitting the launch vehicle before it can get to orbit and deploy its hundreds of satellites; this I think requires the aforementioned manned space-capable planes. This may be the best way to get humans fighting in space. The space-plane, then, should be able to get into enemy-controlled orbits, go low, and fire something at a rocket rising towards orbit. At the speeds and heights involved, ground-based missiles can largely be ignored (not true for satellites, but true for human-controlled powered flight), so the defense is basically another space-plane. They would probably fight each other much as modern jet planes, but with the ability to dodge in and out of atmosphere, with all the maneuvers that implies - go down and you can get Gs out of your wings, go up and you can flip over and shoot backwards at a pursuer.
Posts: 10645 | Registered: Jul 2004
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posted
I actually like the Galactica design. It makes sense to me that a ship would have to be large enough to maintain adequate environmental controls, living quarters, recycle plants, et cetera to make long voyages possible.
Such a ship would have poor maneuverability and would only be good for FTL or hyperdrive/warping/inserttheoryhere traveling. It should have weapons intercept ability for protection. If you are anticipating a fight, it should have small, maneuverable, and armed spaceships to protect it and engage enemies.
Posts: 2445 | Registered: Oct 2004
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1) Engines. Since we have not decided on exactly what form the "engines" will take, then I get to choose what I think will work. A large central "engine" with exhaust modules evenly spaced around the ship would allow for very great mobility in almost any direction.
2) Needs to have room for guns and needs a large profile in order to aim those guns. no you don't. Old time wooden ships didn't take up space on their decks for guns. Most were stuffed in the holds, and fired when the gun ports opened. But we are not talking many guns here. We are talking missiles. Missiles launched from all over the ship, not just one area, would be a) less vulnerable to being completely removed by one lucky strike of the enemy, b) not cause a major loss of striking distance by having to fly from the other side of the ship, around the ship, then in to the enemy.
So what I am suggesting is not officially a sphere. It is a construction of triangles placed in such a way as to create a sphere (Buckyball?) The center of each sphere contains the engine exhaust system which moves the ship. At each corner of the triangle sits either 1) a point defense laser system, 2) a missile launch tube, or 3)an airlock combined with part of the sensor array/communications array/missile guidance system.
Posts: 11895 | Registered: Apr 2002
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quote:FTL travel is not utter fantasy it IS science fiction is well grounded in thereotical physics, see Alcubierre Drive, and there is quite a bit of recently released theoretically work being done by NASA that implies that FTL IS possible.
Also coilguns/railguns can be used to launch heavy payloads into orbit.
1st about science fiction: There's a movement of sorts in the literary sci fi community called MundaneSF-- it focuses on what is scientifically plausible.
FTL is right out according to most Mundane writers.
(I've got some personal problems with the Mundane SF crowd-- not the idea, per se, but some of their manifestos have been...well, insulting to other speculative fiction writers)
Now about those railguns launching material into orbit-- where will you be getting all the energy for the launch?
I tend to see more fighting being done by AI/robot/remote control in the future; I think the human factor gets romanticized far too much without any real reasonable basis.
Posts: 14554 | Registered: Dec 1999
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posted
Seriously, the type of FTL drive your fantasy environment provides really determines what types of warfare are possible, even if most science fiction on TV doesn't explore the repercussions* because its well, difficult to do while staying interesting on tv.
* (books can be better, or rather...I would say that they have a much bigger variance in quality with a marginally higher mean so if you pick the best ones they will be better than the best on TV)
$$$ spoilers for a few shows $$$
Babylon 5 explores this a bit, jump gates can provide a bit of a bottleneck for smaller craft requiring bigger carrier craft. They also become a strategic point to attack. On the other hand, the energy release involved in forming an exiting jump-point becomes a tactic that can be taken advantage of, the Blackstar is one obvious example and the consequences are not fully explored. (e.g. a static station like Babylon 5 would seem like an obvious target and a big fleet like at the Battle of the Line could just open jump-points on top of a defending fleet making that extremely hazardous)
Star Trek is really inconsistent between variations for good reasons (plot, many writers) but the Picard Manuver is a good example of what happens when you do not have FTL sensors but you do have FTL weapons, which also dictates what FTL weapons are effective.
BSG has its concept of directly jumping from point to point, which is a massive strategic nightmare IMHO. In the series, they explore this by having Galactica jump inside an atmosphere bypassing defenders. This is a nightmare since an offensive force could always do this, jump in nukes to any strategic planet or resource without risking any engagement.
As a fun example, if we're talking about something approximating real life with *just* easy FTL travel, you do have to deal with issues like not having FTL sensors and you do have problems with relativity. For example this is one issue that needs to be resolved:
quote: For non-relativistic objects Newton defined momentum, given the symbol p, as the product of mass and velocity -- p = m v. When speed becomes relativistic, we have to modify this definition -- p = gamma (mv)
Notice that this equation tells you that for any particle with a non-zero mass, the momentum gets larger and larger as the speed gets closer to the speed of light. Such a particle would have infinite momentum if it could reach the speed of light. Since it would take an infinite amount of force (or a finite force acting over an infinite amount of time) to accelerate a particle to infinite momentum, we are forced to conclude that a massive particle always travels at speeds less than the speed of light.
Conversely, if you really *had* a drive that could manage to accelerate something to near-light speed it could essentially have "near"-infinite momentum or "near"-infinite energy. Whats the point of armour against something like that?
I think Star Trek wimps out on this part by always (IIRC) having ramming at low sublight speeds and the one time they did consider attempting it at warp (Best of Both Worlds II), they wimped out.
So you really *can't* divorce the discussions of weapons from your baseline rules for FTL travel, the mechanics of FTL dictate what is effective and what is not, making this discussion rather pointless really.
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I agree with Mucus about needing to define FTL in order to understand how warfare can be conducted.
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Blayne Bradley
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quote:Originally posted by Scott R:
quote:FTL travel is not utter fantasy it IS science fiction is well grounded in thereotical physics, see Alcubierre Drive, and there is quite a bit of recently released theoretically work being done by NASA that implies that FTL IS possible.
Also coilguns/railguns can be used to launch heavy payloads into orbit.
1st about science fiction: There's a movement of sorts in the literary sci fi community called MundaneSF-- it focuses on what is scientifically plausible.
FTL is right out according to most Mundane writers.
(I've got some personal problems with the Mundane SF crowd-- not the idea, per se, but some of their manifestos have been...well, insulting to other speculative fiction writers)
Now about those railguns launching material into orbit-- where will you be getting all the energy for the launch?
I tend to see more fighting being done by AI/robot/remote control in the future; I think the human factor gets romanticized far too much without any real reasonable basis.
Nuclear Fusion?
To define the discussion within a more narrower scope lets keep FTL as being the "Harry Turtledove Drive" where basically to jump between stars requires the craft to travel far enough away from a gravity well that it can safely jump away.
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That just shows your ignorance, right there. Poul Anderson used the concept before Turtledove had ever seen a lizard. And I'm sure he was not the first.
Posts: 10645 | Registered: Jul 2004
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quote:FTL travel is not utter fantasy it IS science fiction is well grounded in thereotical physics, see Alcubierre Drive, and there is quite a bit of recently released theoretically work being done by NASA that implies that FTL IS possible.
From Wikiepedia:
quote:However, there are no known methods to create such a warp bubble in a region that does not already contain one, or to leave the bubble once inside it, so the Alcubierre drive remains a theoretical concept at this time.
quote:Significant problems with the metric of this form stem from the fact that all known warp drive spacetimes violate various energy conditions. It is true that certain experimentally verified quantum phenomena, such as the Casimir effect, when described in the context of the quantum field theories, lead to stress-energy tensors which also violate the energy conditions and so one might hope that Alcubierre type warp drives could perhaps be physically realized by clever engineering taking advantage of such quantum effects. However, if certain quantum inequalities conjectured by Ford and Roman hold, then the energy requirements for some warp drives may be absurdly gigantic, e.g. the energy -1067g might be required to transport a small spaceship across the Milky Way galaxy.
We don't know how to make them -- we don't even have a theory on how to make them. All we have is that the mathematics does not prohibit them from existing and the mathematics shows they could create FTL. Well there are a hell of a lot of things that the mathematics works out for that are total and complete fantasy. As the great Richard P Feynman said: "Physics is to Math as sex is to masturbation." Pretty much all FTL theories are just masturbation right now. We have no theories on how to make them actual practical factual realities.. all we know is the math seems to work okay in our current theories. Most of them seem to take advantage though of the huge holes left by our lack of understanding of quantum gravity. Which makes them even closer to fantasy.
quote:Also coilguns/railguns can be used to launch heavy payloads into orbit.
No again, the power requirements are prohibitive. Also the accelerations involved would flatten anything but raw materials and then there's risk of what happens if you miss and undershoot -- no one would allow it. In addition they could only launch magnetically charged payloads. Which means only natural magnets or electromagnets. And any electromagnetic payload that has a field strong enough to be used like that would again have prohibitive energy requirements. We're not just talking bullet trains at 300 mph here, we're talking 15000 mph orbital velocities. And that's after air resistance and gravity have done their things. Which means when it leaves the gun it had better be going a hell of a lot faster.
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I would make a randomized-honeycomb-type ship, as far as profiles go. Since we are assuming no real aerodynamics (being space and all), something that could cause problems for tracking and locking weapons systems would be preferable (a must, at least in part, at the velocities you could get to). The issue of a sphere as a profile, while space efficient, it is also easier to predict where it can be.
Heck, make it an actively randomizable largely empty ship. Sure, they could aim at the weapons installations, which would have to remain somewhat fixed, but that still provides a better chance to flee without major damage, no?
posted
If we stuck a launch base on the moon, powered the rail gun with material brought up via space elevator, then maybe your launch scenario would work out well...
Eric James Stone had a great story in Analog a couple years ago about a space elevator being built over the ocean...
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Blayne Bradley
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Alcon you are in no way participating in the spirit of the discussion, I am talking what theroetical technologies we can conceivably have availiable to make the most possible/plausible starship for war purposes to project force.
Its like you have a group of nerds talking about 4th Edition and suddenly a hot girl comes in and snickers at them for them going to be virgins for the rest of ou-their lives.
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Blayne, and then your last post is like having one of the nerds comeback with some lame response about how the hot girl is no 7 of 9. In other words, unproductive, and bound to devolve the conversation into anything but the original topic.
quote:Originally posted by Blayne Bradley: Harry Turtledove is the first author to use it that I have read. So for now I credit Harry for it.
And I suppose you would also credit Bill Gates with inventing the operating system on the grounds that Windows was the first one you've personally used?
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quote:Originally posted by King of Men: That just shows your ignorance, right there. Poul Anderson used the concept before Turtledove had ever seen a lizard. And I'm sure he was not the first.
Heck, *I* use that idea in my fiction, and I haven't read either of them!
quote:Originally posted by Bokonon: Blayne, and then your last post is like having one of the nerds comeback with some lame response about how the hot girl is no 7 of 9. In other words, unproductive, and bound to devolve the conversation into anything but the original topic.
-Bok
The point is that Alcon is objecting more on engineering grounds then theoretical grounds, even if we tossed out FTL for the mean time and keep it an in system Earth vs Martian Human colony sort of thing or Earth vs Space colonies we still end up with warships to project force. There is significant progress with railguns/coilguns in their development, the US Navy hopes to have one in service by 2012/2020. It is not hard of a stretch to imagine using railguns to launch construction materials into orbit once the engineering issues are solved.
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It seems that if we use rail guns or any sort of projectile artillery, there has to be some sort of apparatus on the opposite end of the ship that fires something like compressed gas in synch with the guns so as to keep the ship from spinning or moving.
Lasers would not have this problem.
Would it be a terrible idea to use some sort mobile EMP generating device that would fire like a missile and initiate on a timer? Or would generating an EMP that could disable a battleship sized craft not be plausible?
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quote:The point is that Alcon is objecting more on engineering grounds then theoretical grounds, even if we tossed out FTL for the mean time and keep it an in system Earth vs Martian Human colony sort of thing or Earth vs Space colonies we still end up with warships to project force. There is significant progress with railguns/coilguns in their development, the US Navy hopes to have one in service by 2012/2020. It is not hard of a stretch to imagine using railguns to launch construction materials into orbit once the engineering issues are solved.
Okay, so lets take a look at those warships. We've already established that cooling is not easy in space, nor is power production -- since doing that on any kind of large scale requires lots of cooling. That rules out high powered propulsion systems or weapons, limiting us to mass drivers and missiles. Since our propulsion systems require us to use ballistic orbital trajectories to get from point a to point b this isn't too much of a problem for long distance targeting. Even low thrust high specific impulse systems like the Ion Drive wouldn't really be able to preform evasive maneuvers for long with out exhausting their fuel supplies and likely ending up way off course and just spinning out into the void and crashing into their target rather than making a nice orbital entry. On the other hand, arming ships with missiles and mass drivers would be highly impractical: remember launch costs in the thousands of dollars per kilogram. That extra mass would also up the fuel costs for changing orbits -- so the more ammunition you carry the harder it gets to get the delta V you need to get anywhere. With the distance and time scales we're talking about for interplanetary war you'd likely need quite a bit of supplies and ammunition to operate a combat vessel. It goes up exponentially and before long it would get prohibitively expensive to arm or armor a warship. Armor's heavy, weapons are heavy and power hungry and it's hard enough today for us to design space craft to just get from point a to point b with the bare essentials. Even with possible theoretical drives of today, warships just wouldn't be practical.
It would be much more practical to develop missiles that could be launched from the surface of a planet towards a target in any orbit. Since the orbits are known, it'd be easy to target, any craft would be a sitting duck. Since practically only so much ammo could be brought, armor would be too heavy (and not likely able to resist a nuclear blast) and dodging isn't really possible with the propulsion systems available(not to mention guidance on the missiles) it would be easy to detect an incoming ship and then just lob missiles at them till they run out of point defense, fail to shoot one down, or simply drive themselves off course trying to dodge them. If you take into account that if we're talking Mars-Earth there's a 6 month travel time in which to lob missiles and those missiles could very easily be nuclear (if they went off in orbit people would care, but in deep space?) any warship would be a sitting duck.
If a decently developed Mars colony and Earth went to war it would probably be more like: "We're not talking to each other, nyah!" It'd be the ultimate stalemate.
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Blayne Bradley
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or Earth can just glass the planet and start over.
And once more your opposing this on grounds of engineering, once the problems are solved they can be used, were imagining this on the assumption that the engineering problems like nearly every single human problem has been solved.
We go about this with the assumption that cooling can be eventually done, that energy is not a problem in the future since we can probably have fusion reactors/ion engines. The counter assumption that "this isnt possible because it is impractical as of now" is counter productive to the discussion.
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quote:Originally posted by Scott R: I tend to see more fighting being done by AI/robot/remote control in the future; I think the human factor gets romanticized far too much without any real reasonable basis.
AMEN! Heck, that's where air warfare is headed in the near future due to g-forces and other factors. The F-22, F-23 and F-35 are probably the last manned fighters the USAF will order. Possibly there will be manned carrier/cruiser type space battleships to launch drones.
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quote:Originally posted by BlackBlade: It seems that if we use rail guns or any sort of projectile artillery, there has to be some sort of apparatus on the opposite end of the ship that fires something like compressed gas in synch with the guns so as to keep the ship from spinning or moving.
Lasers would not have this problem.
They most certainly would. You cannot escape Newton; put out momentum X in direction Y and you will acquire momentum X in direction -Y.
Posts: 10645 | Registered: Jul 2004
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quote:or Earth can just glass the planet and start over.
And once more your opposing this on grounds of engineering, once the problems are solved they can be used, were imagining this on the assumption that the engineering problems like nearly every single human problem has been solved.
We go about this with the assumption that cooling can be eventually done, that energy is not a problem in the future since we can probably have fusion reactors/ion engines. The counter assumption that "this isnt possible because it is impractical as of now" is counter productive to the discussion.
Then your discussion isn't "What's practical now" as advertised in the first post. It's science fiction. Which is exactly what I claimed. And still borderline fantasy with some of the things you've claimed.
And my argument considered fusion and fission as possible power sources. Their cooling requirements and mass requirements are pretty ridiculous. They also have their own fuel requirements. If we go so far as to say we assume the cooling is solved with minimal mass and we equip the warships with VASIMRs -- the best today has to offer, Specific Impulses in the hundred thousands and Exhaust Velocities in the thirty thousands and it uses hydrogen for fuel, the lightest fuel there is. Then you still have to deal with the fact that they will be sitting ducks to ground launched missiles while in transfer orbits. It's possible they could try and use lasers for point defense (since we're assuming we've solved cooling), but the easy solution to that is to simply mirror coat the missiles. The lasers would then get harmlessly reflected. So we're still in a sitting duck situation.
The same would go for any missiles launched from planet to planet, re: Earth glassing Mars. The Martians would have six months to detect and pick off any missiles launched from Earth using their own missiles. I stand by my case, stalemate.
On the other hand, while warships would still be impractical using the VASIMR and Fusion, colony ships would not and exploration ships would not. *drool*
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quote:They most certainly would. You cannot escape Newton; put out momentum X in direction Y and you will acquire momentum X in direction -Y.
Yeah, but the momentum vs energy (Ie Damage) would be much smaller I would think. So it would be much less of a problem.
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posted
I feel that either lasers or guided missiles are key. Mass drivers are just too slow at the distances in a space battle. Just like modern fighters don't dogfight with machine guns because the range of missiles is massively greater, I see the same thing happening in space.
Mass drivers will be limited to point defense weapons, or for firing at stationary targets. With the distances involved and the defensive maneuvering of the ships, rail guns won't be useful against moving targets.
I also think that either guided missiles or robotic fighters will be the key to success. Human-piloted ships are severely limited in their acceleration by the human body. Unmanned ships and missiles will be able to accelerate and maneuver at much higher speeds.
Posts: 3950 | Registered: Mar 2006
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quote:Originally posted by Blayne Bradley: assuming we only had the theoretical 21st century technologies we currently possess.
quote:Originally posted by Blayne Bradley: And once more your opposing this on grounds of engineering, once the problems are solved they can be used, were imagining this on the assumption that the engineering problems like nearly every single human problem has been solved.
We go about this with the assumption that cooling can be eventually done, that energy is not a problem in the future since we can probably have fusion reactors/ion engines. The counter assumption that "this isnt possible because it is impractical as of now" is counter productive to the discussion.
As Alcon just summed up, you're changing the parameters of this discussion mid-stream. I'll just address the "realistic" propulsion aspect (as that's my field of expertise) 1) Ion drives: Current Ion drives tend to be on the order of a few kg for just the thruster itself (ignoring all the feed system and power system components) and while they have a very nice Isp (efficiency) ~3000 seconds, they only provide ~10 mN of thrust... that means that the ~10 kg component could just about lift a piece of paper. These would have effectively no place on a combat vessel (at least not for any kind of combat maneuvering) and if they were used for long-range propulsion it would mean excessively long trips (i.e. months+ between Earth and Mars).
2) Other high efficiency systems (such as pulsed detonation and nuclear thermal propulsion) tend to operate with gaseous hydrogen as a propellant. While some of these might be more viable (i.e. they can sometimes provide significant thrust) they are still far from anything that could be used for combat purposes. A proposed earth-mars exploration mission (3-4 man crew with just the supplies to get there... factors of magnitude lighter than any kind of armed and armored combat craft) would take months to get there, was about 90-95% propellant (by mass) and about 95-99% highly sensitive cryogenic propellant tanks (by volume). Add to that something like a football field worth of radiators to deal with excess heat from the nuclear reactor and the tank's cryogenic system. So basically you'd be flying around in the hindenburg in space (not something I'd want in a combat situation). (note: this was my class's senior design project, and we were being pretty agressive with most of the technology we were proposing).
short summary: with 21st century "realistic" technology space battleships are not going to happen... now short range, orbital fighters might be reasonable, but that sounds like another discussion.
If you want to shift this more fully into the realm of quasi-reasonable science fiction, then just admit it.
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