Got a Real-World Weapon or Armor Question? Mk. VIII

[fusilier]

I don't think artillery would work well in outer space. It's way too slow to hit any moving target at more than point blank range, the projectiles are heavy (you don't want any additional mass on a space ship - it costs lots of fuel) and the recoil will throw your ship around, ruining your aim and maneuvering (conservation of momentum is a bitch).
It would work fine from orbit (at least on stationary targets), but it just can't match the range of lasers (or sensors) when in open space.

Yeah, but I think the point is that lasers aren't up to task -- yet. So artillery is feasible. Weight issues and resupply aside (pretty much any of these technologies will require more effective ways of getting supplies into space), recoil can be engineered around -- recoilless cannon do exist. Rockets and "torpedos" would be another viable option.

[Autolykos]

If you're takling about today, there won't be any battles in open space anyway (as there is no use in sending any military stuff there in the first place). And once you're in orbit, the distances are much shorter, which makes cannons in fact somewhat feasible. I would still prefer rockets, though. While the cannon takes less fuel, you need the fuel on your spacecraft instead for compensating recoil and getting back to your original orbit (you just can't fool Newton...). Plus, rockets are way easier to aim/guide to your target - especially in space, where the projectiles can't be steered by aerodynamics.

[fusilier]

If you're takling about today, there won't be any battles in open space anyway (as there is no use in sending any military stuff there in the first place). And once you're in orbit, the distances are much shorter, which makes cannons in fact somewhat feasible. I would still prefer rockets, though. While the cannon takes less fuel, you need the fuel on your spacecraft instead for compensating recoil and getting back to your original orbit (you just can't fool Newton...). Plus, rockets are way easier to aim/guide to your target - especially in space, where the projectiles can't be steered by aerodynamics.

In the case of most recoilless cannon designs, you need more propellant, as that's what's used to counteract the recoil. Which basically works out to more "fuel" whichever way you look at it. Some, very early designs, offset recoil using a captured weight, but they weren't terribly effective.

Also, feasibility may hinge around how many times you expect to fire a cannon. Most laser setups are considerably heavier than a cannon and it's ammunition. So if you only need to carry a handful of rounds into battle, then a cannon may actually be the fuel saving weapon. On the other hand, if you are expecting to be firing a lot, then lasers that can be powered from on board energy generation *might* seem like a better option. But, they would still burn up fuel! So unless you can make your lasers more efficient than artillery, they may in fact use more energy (i.e. fuel). There's no reason to assume, at this point, that lasers would be more efficient than explosives.

[Matthew]

Interesting new series on Channel Four: Back From the Dead (http://www.channel4.com/programmes/back-from-the-dead/). Will it be good or bad? Guess we will have to wait and see! :smallbiggrin:



Now this is a highly fascinating subject. But TV shows like exiting stories, not lab reports. Could be really cool, or as awful as Deadliest Warrior.

Finally got around to watching these. The crusade one was passable, and as expected was based largely on the Jacob's Ford findings; of particular interest to me was the prospective archer, who had perhaps worn down one of his front teeth my using it in bowyer or fletcher practices. Seems plausible to me, but I have no idea what techniques are necessary for such things.

Unfortunately, the Japanese one was hilariously bad. On the positive side they had Stephen Turnbull giving sound historical narrative, on the bad side they literally had samurai flying through the air. The katana worship was out in full force, and any misleading cliché or crazy thing they wanted to say was delegated to the narrator, as usual. A lot of this episode was wild conjecture and over dramatisation, it seemed to me.

[Autolykos]

But, they would still burn up fuel! So unless you can make your lasers more efficient than artillery, they may in fact use more energy (i.e. fuel). There's no reason to assume, at this point, that lasers would be more efficient than explosives. I think I wasn't clear here. The scarce resource on a spaceship (usually) is not energy, but reaction mass. Firing a laser does not require any reaction mass as it does not impart momentum on your spacecraft (technically not correct, as light does have a momentum - but it is so minuscule that it can be safely ignored for all practical reasons). The cannon however requires you to burn reaction mass to compensate its momentum (the "recoilless" designs just burn the reaction mass while firing, so they don't save you anything).

[Hawkfrost000]

I think I wasn't clear here. The scarce resource on a spaceship (usually) is not energy, but reaction mass. Firing a laser does not require any reaction mass as it does not impart momentum on your spacecraft (technically not correct, as light does have a momentum - but it is so minuscule that it can be safely ignored for all practical reasons). The cannon however requires you to burn reaction mass to compensate its momentum (the "recoilless" designs just burn the reaction mass while firing, so they don't save you anything).

But you get your energy from reaction mass no? Thus if reaction mass is scarce then the energy obtained from that reaction mass must be scarce as well.

DM

[Autolykos]

Nope. Energy is most commonly generated by solar panels and nuclear reactions. None of them provide any usable reaction mass.

[Hawkfrost000]

Nope. Energy is most commonly generated by solar panels and nuclear reactions. None of them provide any usable reaction mass.

For satellites yes, not for spaceships.

Solar Panels are inefficient and fragile, they would not stand up to the necessary acceleration that space combat.

Nuclear reactions can be used to directly provide acceleration in large amounts, see Project Orion, does that not mean they have reaction mass? I cant see them providing forward motion purely through Electromagnetic Radiation.

[Autolykos]

Even for spaceships, you wouldn't generate energy the same way you generate thrust. And in general you require much less materials for energy (just look at how much energy you can get out of a few grams of hydrogen in a fusion reactor, and compare that to the thrust you could generate with it).
If you mean the A-bomb-powered rocket with Project Orion, most of the energy is actually wasted (as it goes away in the form of radiation, and not as actual moving particles which would provide much more thrust).
In general, you want to push out your reaction mass as fast as possible (to get more momentum from the same mass). To achieve this, most of the energy stored in your fuel should end up as kinetic energy of the reaction mass, instead of radiating away into space.
I think most of the confusion comes from the fact that chemical rockets use their fuel for both energy and reaction mass (ion engines for example don't).
EDIT: Nitpick: Solar panels could probably stand higher accelerations than the passengers. It's just that they aren't of much use unless you happen to be near a star.

[fusilier]

But unless you can generate enough energy on the fly from solar panels to power a laser (not likely), then you're going to have to store that energy. Batteries and the like can be very heavy, even when empty. Also solar panels, and the systems to operate them, do not have negligible weight.

[Kwinza]

can anyone give me some up to date info on this please;

http://en.wikipedia.org/wiki/Trojan_Ballistics_Suit_of_Armor

whats happening with this now? or has it been supperseded by a better suit?

cheers :)

[Thiel]

can anyone give me some up to date info on this please;

http://en.wikipedia.org/wiki/Trojan_Ballistics_Suit_of_Armor

whats happening with this now? or has it been supperseded by a better suit?

cheers :)
Not that I know of. I do know that none of the serious military news sites or forums wants to touch it with a burning stick.
And to be honest I understand why. Firstly, because it doesn't actually provide any more protection than existing body armours. True, the arms and legs are protected by bullet-proof fabric, but without padding or ballistic plates it won't do you much good. The plates you see are made out of the same plastic that knee protectors are.

The helmet aren't exactly a stroke of genius either. It badly limits your vision and in its current state it isn't compatible with US Army or CF night-vision gear. I like the idea of a trooper sized ventilation system, but in the real world it's going to clog up with dust fairly quickly (This is a problem on vehicles and they don't drag their air intakes along the ground)

The "last words" recorder seems like an excellent way to demoralize your troops and their families. We all want to remember our troops as heroes, but recording their last words isn't going to help. Rather the opposite really, because lets face it, if they are not in shock or unconscious chances are they're going to be crying for their mother and/or life. Not exactly how we want to remember them or how they deserve to be remembered either

Then there's the two pistols. There's two of them, that should tell you enough.

Then there's the foot shovel. I've hiked quite a bit and I can tell you if there's one place where you don't want extra weight it's feet.

Why does the clock have to be in the crotch? Put it on the wrist where we're used to have it. If you're worried about the troops taking their hands of their gun then put it on the inside.

The voice-box is just stupid. We're trying to avoid becoming terminators in the eyes of the locals. Plus, it'll make identification harder.

Putting lights on the helmets aren't a terribly smart idea either. It'll be impossible to hold steady while moving and they'll provide a perfect target for a sniper. (One of the first thing they teach police officers is to hold their torch away from their body since people tends to shoot at it.)

[Kwinza]

I thought the entire suit was meant to be bullet proof? or was that just hype?

[gkathellar]

Nothing is bullet-proof. Bullet-resistant, maybe, but so is existing armor —*and when you take other factors into account, the suit looks significantly worse.

Real powered armor remains a long way off.

[hamishspence]

Now the thread's exceeded 50 pages, will a new thread be put up?

[Autolykos]

But unless you can generate enough energy on the fly from solar panels to power a laser (not likely), then you're going to have to store that energy. Batteries and the like can be very heavy, even when empty. Also solar panels, and the systems to operate them, do not have negligible weight.Absolutely true. However, the entire system is self-sufficient (or at least practically self sufficient when using nuclear power). Resupplying a space ship with shells (or anything else, for that matter) would be a royal PITA. I could see a gun being used for disposable killsats or small fighters operating from a large carrier ship, but not for anything that has to be either usable in long-range engagements (more than, say, 10000 km) or able to operate independently. And even then I'd still prefer rockets.

[razark]

But unless you can generate enough energy on the fly from solar panels to power a laser (not likely), then you're going to have to store that energy. Batteries and the like can be very heavy, even when empty. Also solar panels, and the systems to operate them, do not have negligible weight.
Let's not forget that you need some way to dispose of waste heat generated by the spacecraft. Cooling is an issue even with today's spacecraft, and they're not firing cannons or lasers, or even generating nearly enough power to do so.

Solar panels and radiators are going to be the targets of the first volley in a space battle. Knock out the cooling system and dodge enough incoming attacks, and wait for the enemy to cook itself to death.

Armor is heavy, as well. Spacecraft, for the foreseeable future, are going to be thin hulled, lightweight creatures. Forget lasers, artillery, etc. Missiles would work, but would be heavy, complicated items that would be a problem for logistics. Fifty caliber rifles would be capable of doing considerable damage to anything that will be in space in the next few hundred years.

[huttj509]

Armor is heavy, as well. Spacecraft, for the foreseeable future, are going to be thin hulled, lightweight creatures. Forget lasers, artillery, etc. Missiles would work, but would be heavy, complicated items that would be a problem for logistics. Fifty caliber rifles would be capable of doing considerable damage to anything that will be in space in the next few hundred years.

I just have this mental image of "roll down the window Bob, I got my rifle!."

And no, the image does not include spacesuits or pressure control.

[razark]

I just have this mental image of "roll down the window Bob, I got my rifle!."

And no, the image does not include spacesuits or pressure control.

When I first heard about this:
http://en.wikipedia.org/wiki/Salyut_3#On-board_gun
being a defense against possible attack by American Apollo spacecraft, I had just about the same image.


I see space combat beginning much the same way as air-to-air combat:

Enemy pilots at first simply exchanged waves, or shook their fists at each other. Due to weight restrictions, only small weapons could be carried on board. Intrepid pilots decided to interfere with enemy reconnaissance by improvised means, including throwing bricks, grenades and sometimes rope, which they hoped would entangle the enemy plane's propeller. This progressed to pilots firing hand-held guns at enemy planes, such as pistols and carbines. In August 1914, Staff-Captain Pyotr Nesterov, from Russia, became the first pilot to ram his plane into an enemy spotter aircraft. In October 1914, the first airplane to be shot down by a hand gun from another plane happened over Rheims, France. Once machine guns were mounted to the plane, either on a flexible mounting or higher on the wings of early biplanes, the era of air combat began.

[Thiel]

I just have this mental image of "roll down the window Bob, I got my rifle!."

And no, the image does not include spacesuits or pressure control.

Great, now I've got a picture of an astronaut in full suit in blue overalls and a straw hat armed with a shotgun sitting in a rocking chair on one of the ISS's solar panels.

[hamishspence]

Armor is heavy, as well. Spacecraft, for the foreseeable future, are going to be thin hulled, lightweight creatures. Forget lasers, artillery, etc. Missiles would work, but would be heavy, complicated items that would be a problem for logistics. Fifty caliber rifles would be capable of doing considerable damage to anything that will be in space in the next few hundred years.

What about once the Asteroid Belt starts being mined for metals?

[razark]

What about once the Asteroid Belt starts being mined for metals?
First, you have to get the mining ships off the surface of the Earth. Every pound of hull/structure translates to many pounds of fuel to get it to orbit. Once in space, every additional pound of spacecraft is one less pound of mining ability. Our propulsion technology is simply not anywhere close to what it would need to be to start pushing large ships around. Look at a Saturn V. It's the only vehicle that's gotten us any distance away from Earth, and that was only to the moon. The entire stack stood 110.6 meters. Most of that was fuel tank to push a 10.7 meter spacecraft to the moon. 7.5 meters of that was the Service Module, which was needed to return the 3.2 meter tall people can to Earth. Of the Saturn V, less than 3% of the stack made it back to the Earth's surface.

Before we can start pushing out into the solar system, we need better engines. Until then, the only people that would fund a mission would be governments. Private companies could fund a moonshot, Mars mission, or asteroid rendezvous, but there is not enough return on investment to make it worthwhile, and there won't be for quite a while. The future of exploration is in the hands of government, and the future of exploitation is in low Earth orbit, possibly the moon. Mining an asteroid is far in the future.

Nuclear thermal rockets or something more efficient are needed. Even then, mining companies would be looking to use a little spacecraft as possible to haul as much profit making mining results as possible.

[Knaight]

Fifty caliber rifles would be capable of doing considerable damage to anything that will be in space in the next few hundred years.

If we are talking about actual combat between two ships in space, rifles are completely worthless. There is no stealth in space, at least not if anything is running a temperature over 3 K, which everything is. One would expect combat to take place at light minutes away, and at light minutes away even the best rifle is hideously inaccurate. Missiles though? Those can change their trajectory, accelerate far faster than anything with humans in it, and at the collision speeds we are likely to see, could be light and thin (though fuel is always heavy).

[razark]

If we are talking about actual combat between two ships in space, rifles are completely worthless.

Note the key qualifier: "in the next few hundred years." Beyond that time period, when you're handling massive enough amounts of energy to throw big hunks of metal around space, the main limiting factor will be heat. You either need massive radiators, which will be big juicy targets, or a massive heat sink (which just delays the problem of removing the waste heat). Long range, high energy space combat is just not going to happen for a long time, if ever.

[Knaight]

Note the key qualifier: "in the next few hundred years." Beyond that time period, when you're handling massive enough amounts of energy to throw big hunks of metal around space, the main limiting factor will be heat. You either need massive radiators, which will be big juicy targets, or a massive heat sink (which just delays the problem of removing the waste heat). Long range, high energy space combat is just not going to happen for a long time, if ever.

Long range is basically the only option, once one is actually into space. Whoever out ranges the other wins, and that leads inevitably to whoever sees the other first. Space combat is all about information, because space combat is about fragile entities that have highly limited maneuverability, basically no acceleration, and pretty meaningless defenses.

That said, the original discussion was about satellites. Orbital combat and space combat are two very different things, for many reasons. Not the least of which is how easy it is to shoot stuff down from the ground, and how little it takes to hit the ground hard from space. Gravity wells will do that for you.

[fusilier]

Long range is basically the only option, once one is actually into space. Whoever out ranges the other wins, and that leads inevitably to whoever sees the other first. Space combat is all about information, because space combat is about fragile entities that have highly limited maneuverability, basically no acceleration, and pretty meaningless defenses.

That said, the original discussion was about satellites. Orbital combat and space combat are two very different things, for many reasons. Not the least of which is how easy it is to shoot stuff down from the ground, and how little it takes to hit the ground hard from space. Gravity wells will do that for you.

The russians had a manned spy satellite (Almaz) armed with a 23mm cannon -- it was for self-defense, I think against missile attacks. They only tested it remotely, but it was a successful test.

I don't think artillery would be terribly inaccurate in space, even over great distances. Aiming would be a problem for a laser as well. If firing over really great distances, then gravitational fields would have an effect on a projectile, but they also effect light too. So any aiming system would have to take those factors into account.

I think the main benefit to a laser is that it travels at the speed of light. On the other hand, long range artillery firing has been an issue since before ww2, predicting the path of an enemy ship is basically a solved problem. Taking evasive maneuvers under long range artillery fire is also something that has been around for a long time. These problems may be exacerbated by the distances involved in space (although space would have some things that also benefit long range projectile weapons), but solutions of one form or another already exist.

The first question is will the particular issues of space combat, prove too troublesome for artillery fire. I see no particular reason to assume so. Evasive maneuvers would only be successful based upon sufficient warning of incoming shells -- I imagine rapidly changing the direction of a large vessel would be difficult. High velocity artillery shells may be difficult to detect, so detection would mainly rely on detecting that an enemy had fired, with sufficient warning to take evasive action.

Although I'll admit that lasers would be better, but they may have their own problems. They can require massive energy reserves, or the ability to quickly generate energy, both of which may add weight, even in excess of a well stocked magazine. Heat generation and dissipation would be a problem for both lasers and artillery (although it may be less for a recoilless cannon, depending upon how it is mounted).

A long range rocket would take longer to reach it's target, would probably be easier to employ counter measures against, but could at least change it's trajectory, and heat dissipation on the ship would be negligible.

Guided artillery shells do exist:
http://en.wikipedia.org/wiki/M982_Excalibur

Although they may rely upon air effects (no discussion of how the guidance works, but the images show fins), if something similar can be developed for use in vacuum, it may provide a nice compromise between a faster travelling artillery round, and the ability to change trajectory like a guided or homing missile.

The point is, artillery shouldn't be discounted off hand. There are many problems with space combat, that will have to be addressed for any of these systems to work (missiles probably being the easiest to implement). We could probably spend many pages poking holes, and pointing out problems with any one weapon system in space.

For attacking something on the ground from space, then as you said, projectiles don't generate any particular problems.

[Knaight]

A long range rocket would take longer to reach it's target, would probably be easier to employ counter measures against, but could at least change it's trajectory, and heat dissipation on the ship would be negligible.

Guided artillery shells do exist:
http://en.wikipedia.org/wiki/M982_Excalibur

Although they may rely upon air effects (no discussion of how the guidance works, but the images show fins), if something similar can be developed for use in vacuum, it may provide a nice compromise between a faster travelling artillery round, and the ability to change trajectory like a guided or homing missile.
I'm thinking that the ability of the ammunition to change trajectory is basically mandatory. Ships would be visible a very long way out, and missing by a miniscule fraction of a degree off perfect can lead to missing the target entirely. I had some calculations elsewhere, regarding the size of a mount needed to hit something of a certain size assuming you could control the moving parts to a certain distance, and I'll track them down. Suffice to say that a gun of a few meters needs precision to more than the atomic level to hit something a light minute out. Laser, unguided projectile, it doesn't matter.

[Hawkfrost000]

I'm thinking that the ability of the ammunition to change trajectory is basically mandatory. Ships would be visible a very long way out, and missing by a miniscule fraction of a degree off perfect can lead to missing the target entirely. I had some calculations elsewhere, regarding the size of a mount needed to hit something of a certain size assuming you could control the moving parts to a certain distance, and I'll track them down. Suffice to say that a gun of a few meters needs precision to more than the atomic level to hit something a light minute out. Laser, unguided projectile, it doesn't matter.

If this is true then why not consider missiles? They have no recoil and although they are quite heavy they could probably have more destructive power than a shell or slug, especially if they are nukes.

Although they cannot be directly guided (limited by the speed of light) they can be directed to home in on certain targets (by infra red, radar or lasers). I also once heard of a theory that had "starfighters" shepherded a group of missiles to their target, allowing them to react much faster than if they had been guided by the capital ship that launched them.

DM

[fusilier]

I'm thinking that the ability of the ammunition to change trajectory is basically mandatory. Ships would be visible a very long way out, and missing by a miniscule fraction of a degree off perfect can lead to missing the target entirely. I had some calculations elsewhere, regarding the size of a mount needed to hit something of a certain size assuming you could control the moving parts to a certain distance, and I'll track them down. Suffice to say that a gun of a few meters needs precision to more than the atomic level to hit something a light minute out. Laser, unguided projectile, it doesn't matter.

Yeah, I would generally agree with this, but would point out a couple of things. 1. Just because you've spotted other ships, doesn't mean you know that they've fired at you, or that you've even identified them as enemies. As an artillery shell lacks it's own propulsion system, it will be harder to detect than a missile. 2. Artillery shells, and missiles, can be fitted with proximity fuzes, to go off when they are "close enough" and don't need a direct hit. If you are using nuclear warheads, then "close enough" can be quite far. 3. Barrages can allow for statistical spread, although they are wasteful on ammo (and therefore weight).

Still some serious problems with aiming, makes some sort of guided projectile seem more feasible.

[Knaight]

If this is true then why not consider missiles? They have no recoil and although they are quite heavy they could probably have more destructive power than a shell or slug, especially if they are nukes.

I've been arguing for missiles since the beginning. As for guidance systems, those would just have to be contained on the missile.

[Hawkfrost000]

I've been arguing for missiles since the beginning. As for guidance systems, those would just have to be contained on the missile.

Exactly, one could argue that they are easier to detect than an artillery shell. However you could pull all sorts of shenanigans like detonating a first wave of missiles a few thousand kilometers off the target ship then they would be virtually blind and unable to detect the next wave of missiles until its two late.

DM

[Autolykos]

The artillery shell would be hot enough just by friction with the barrel to be easily detectable - so no big advantage over the missile here.
As far as nuclear warheads go - they would definitely fry unshielded electronics over a large-ish distance, but actual destruction would probably be fairly limited (sure, being off by a few kilometers would be no big issue - but that's already pretty close when talking about space combat). Also, crew and electronics have to be somewhat protected against cosmic rays anyway, so the long-range effects might be surprisingly underwhelming.

[gkathellar]

As far as nuclear warheads go - they would definitely fry unshielded electronics over a large-ish distance, but actual destruction would probably be fairly limited (sure, being off by a few kilometers would be no big issue - but that's already pretty close when talking about space combat).

Nukes are much more limited in space than they are in a terrestrial environment. Without a planet's electromagnetic field to bounce off of, the EMP effects are pretty limited. Moreover, since there's no atmosphere to burn, a nuke's explosive power is significantly reduced. Mostly what you're getting from a nuke in space is radiation.

Mind you, in orbital combat the nuke remains the supreme EMP.

[Hawkfrost000]

Nukes are much more limited in space than they are in a terrestrial environment. Without a planet's electromagnetic field to bounce off of, the EMP effects are pretty limited. Moreover, since there's no atmosphere to burn, a nuke's explosive power is significantly reduced. Mostly what you're getting from a nuke in space is radiation.

Mind you, in orbital combat the nuke remains the supreme EMP.

How much radiation are we talking about here? Would there be enough to either kill/injure the crew or damage the hull through large amounts of heat through radiation.

DM

[fusilier]

The artillery shell would be hot enough just by friction with the barrel to be easily detectable - so no big advantage over the missile here.

So a missile is burning fuel, and spewing out hot gases as it travels. An artillery shell is merely going to have heat relative to background. If it's not radiating it's heat efficiently, then how are you going to detect it? (If it is radiating it's heat efficiently, then you won't be able to detect it once it cools off). For that matter how exactly are you detecting the heat signatures of incoming objects -- infrared? Will you be able to detect something that's relatively small, fast, and not leaving a heat trail, with sufficient warning?

[razark]

If it's not radiating it's heat efficiently, then how are you going to detect it?
Radar. We can do it today.


Will you be able to detect something that's relatively small, fast, and not leaving a heat trail, with sufficient warning?
Yes:
http://en.wikipedia.org/wiki/Counter-RAM

[gkathellar]

The recurring problem with all of these suggestions seems to be ratios of mass/energy expenditure to accuracy. Kinetic weaponry never hits, while missiles and artillery require too much energy to field effectively. Lasers have both problems (accuracy and energy). You can get accuracy, but it costs too much. You can reduce the price, but your accuracy is going to be nonexistent.

The root of this problem is with the idea that space combat will take place between independently moving craft. Why would this ever occur? Spacecraft are for transport. Relatively large, predictable targets (planets, space stations) are so much easier to attack, and the potential gains for such attacks are much greater than those of shooting down a ship. If you want to win a war in space, your efforts will be focused on the destruction or seizure of your enemy's habitat — and while armies can credibly defend a habitat from incursion in terrestrial warfare, an armada is useless in space where there are so many angles of attack.

If space warfare is possible, it'll very likely consist of habitats throwing nukes and mass drivers at each other, or at each other's planetary defenses if their intent is to conquer rather than destroy. There's no reason to build ships with guns, because their only conceivable use is to fight other ships with guns, and fighting ships with guns will not win you a war.


How much radiation are we talking about here? Would there be enough to either kill/injure the crew or damage the hull through large amounts of heat through radiation.

DM

I recall that a nuke's effectiveness in space is really distance-dependent. At close range, it'll vaporize just about any target with relative ease — at a reasonable distance, a ship's existing radiation shielding should be able to handle the blast. I can't provide specifics, though.

[fusilier]

Radar. We can do it today.


Yes:
http://en.wikipedia.org/wiki/Counter-RAM

That's cool. But I have to question it's effectiveness against proper artillery rounds. It looks like it was mainly modified (from an anti-missile weapon) to deal with mortar rounds, which are subsonic. UPDATE -- The most detailed article I could find on it didn't mention taking down artillery rounds, only mortar rounds.--

Also sometimes militaries are . . . let's say . . . "optimistic" . . . when reporting the effectiveness of certain countermeasures. Take for example the Patriot missile controversy.

Of course, countermeasures will develop, and ways around them will develop as well. There hasn't been much combat to prove many of these technologies, so for now, anti-ship missiles haven't been rendered obsolete by such systems.

[Thiel]

That's cool. But I have to question it's effectiveness against proper artillery rounds. It looks like it was mainly modified (from an anti-missile weapon) to deal with mortar rounds, which are subsonic. UPDATE -- The most detailed article I could find on it didn't mention taking down artillery rounds, only mortar rounds.--

Also sometimes militaries are . . . let's say . . . "optimistic" . . . when reporting the effectiveness of certain countermeasures. Take for example the Patriot missile controversy.

Of course, countermeasures will develop, and ways around them will develop as well. There hasn't been much combat to prove many of these technologies, so for now, anti-ship missiles haven't been rendered obsolete by such systems.

The standard integration test for the SeaWolf system is to shoot down 4.5in artillery shells. Those are very much supersonic.
The Aster missile family is also supposed to be able to do it.
There's several hard-kill systems available that can be fitted to tanks.

[Autolykos]

So a missile is burning fuel, and spewing out hot gases as it travels. An artillery shell is merely going to have heat relative to background. If it's not radiating it's heat efficiently, then how are you going to detect it? (If it is radiating it's heat efficiently, then you won't be able to detect it once it cools off). For that matter how exactly are you detecting the heat signatures of incoming objects -- infrared? Will you be able to detect something that's relatively small, fast, and not leaving a heat trail, with sufficient warning?
I'm not contesting that a missile will be easier to detect (wrote so myself IIRC). I'm just saying that artillery shells will be far from undetectable. The rate at which the shell loses heat in the beginning probably won't even affect its detectability in the long run, as it may be colder if it is built to radiate more heat, but will radiate as much as a hotter object with better insulation (didn't do the math yet, so I might be wrong here). Any way, it will take a very long time for the shell to cool to a temperature within the standard deviation of the microwave background (2,725K ± 0,002K) and actually become undetectable (EDIT: by thermal means - radar still works).

[fusilier]

The standard integration test for the SeaWolf system is to shoot down 4.5in artillery shells. Those are very much supersonic.
The Aster missile family is also supposed to be able to do it.
There's several hard-kill systems available that can be fitted to tanks.

I'm not sure where to find this information. The wikipedia entry for the SeaWolf system, claims that on *one* occasion during testing it successfully intercepted a 114mm shell. (See previous statement about "optimism")

Most of what I can find, is anti-missile countermeasures. I'm sure they're working on some anti-artillery measures, but I haven't seen much that's very convincing (reactive armor seems to be the way to go for an active defense against artillery).

[Knaight]

Most of what I can find, is anti-missile countermeasures. I'm sure they're working on some anti-artillery measures, but I haven't seen much that's very convincing (reactive armor seems to be the way to go for an active defense against artillery).

Its worth noting that artillery is likely easier to shoot down in space. For one thing, you are trying to intercept a linear trajectory instead of a parabolic one (or technically an elliptical one that can be modeled as a parabola in most cases), for another range is likely to be drastically increased simply because planetary gravity is a non issue, and, for that matter, its easier to hit something with a linear trajectory. In short, there is more time to shoot down an easier target.

[fusilier]

I'm not contesting that a missile will be easier to detect (wrote so myself IIRC). I'm just saying that artillery shells will be far from undetectable. The rate at which the shell loses heat in the beginning probably won't even affect its detectability in the long run, as it may be colder if it is built to radiate more heat, but will radiate as much as a hotter object with better insulation (didn't do the math yet, so I might be wrong here). Any way, it will take a very long time for the shell to cool to a temperature within the standard deviation of the microwave background (2,725K ± 0,002K) and actually become undetectable (EDIT: by thermal means - radar still works).

So I still don't understand how you intend to detect heat. Vacuum is an excellent insulator, so things in vacuum give off heat through radiation only. Radiating heat can be tricky to do. In fact one of the big problems with lasers (rail guns) and cannons will be heat dissipation, and large radiating surfaces would have to be employed. Which someone else already noted would be a weak spot that can be targeted.

If an object isn't efficiently radiating heat how do you detect it thermally in vacuum? Is infrared sensitive enough?

[fusilier]

Its worth noting that artillery is likely easier to shoot down in space. For one thing, you are trying to intercept a linear trajectory instead of a parabolic one (or technically an elliptical one that can be modeled as a parabola in most cases), for another range is likely to be drastically increased simply because planetary gravity is a non issue, and, for that matter, its easier to hit something with a linear trajectory. In short, there is more time to shoot down an easier target.

*IF* you can detect it early enough! That's the key to any of these counter measures. And that's where artillery trumps a missile -- it's faster and smaller: detection is theoretically more difficult, and reaction time needs to be shorter.

Also you can overwhelm a point defense system, but you could do that with missiles too.

[Hawkfrost000]

So I still don't understand how you intend to detect heat.

Infrared Telescopes? :smallconfused:

DM

[Knaight]

*IF* you can detect it early enough! That's the key to any of these counter measures. And that's where artillery trumps a missile -- it's faster and smaller: detection is theoretically more difficult, and reaction time needs to be shorter.
Longer ranges means more time to accelerate, and in a vacuum you can achieve functionally constant acceleration (strictly speaking, you slow down ever so slightly, but you would have to be traveling at relativistic speeds for that to be relevant at all). For that matter, greater than constant acceleration is likely, as long as fuel is the majority of a missiles weight. Artillery isn't faster in space, and while it might be closer when you detect it, it will still take longer to get there. At which point it will miss anyways, as not being able to hit from a decent range is still an issue.

As for detecting it early enough, consider the detection capacity of the Hubble space telescope. And then realize that anything with people on it in space, or anything burning fuel or using a battery is significantly above 3K, and the infra red will be glaringly obvious. You can get drones pretty cold, but 3K is simply not within reach in the foreseeable future.

[razark]

Artillery isn't faster in space, and while it might be closer when you detect it, it will still take longer to get there. At which point it will miss anyways, as not being able to hit from a decent range is still an issue.
Add thrusters and a seeker head to an artillery shell, and you avoid the missing problem. Or fire a missile as an artillery projectile. When it closes within a specified distance, activate the seeker head, locate the target, and fire the engine. It won't have time to accelerate to it's full potential velocity, but if you're not going for a kinetic kill, that doesn't matter quite as much.

[gkathellar]

Add thrusters and a seeker head to an artillery shell, and you avoid the missing problem. Or fire a missile as an artillery projectile. When it closes within a specified distance, activate the seeker head, locate the target, and fire the engine. It won't have time to accelerate to it's full potential velocity, but if you're not going for a kinetic kill, that doesn't matter quite as much.

This is roughly the principle behind the missile bus — fire a container into range, which will then unload multiple warheads while you remain at a safer distance.

[hamishspence]

If space warfare is possible, it'll very likely consist of habitats throwing nukes and mass drivers at each other, or at each other's planetary defenses if their intent is to conquer rather than destroy. There's no reason to build ships with guns, because their only conceivable use is to fight other ships with guns, and fighting ships with guns will not win you a war.

A moving, heavily armed and armoured habitat come to attack another one, is basically, a ship with a gun.

[Karoht]

This is roughly the principle behind the missile bus — fire a container into range, which will then unload multiple warheads while you remain at a safer distance.I'd rather just use a rail gun to throw an entire bus at a target, personally. Just more my style.

Though an entire bus filled with and covered with missiles is just fun to imagine.

[Maquise]

I have a question about lammelar armor. How does it compare to other armor in terms of protection, weight and ease of wear, and construction?

[Spiryt]

I have a question about lammelar armor. How does it compare to other armor in terms of protection, weight and ease of wear, and construction?

Wow, that's one broad question, sheriff. :smallwink:

Lammellar generally was used throughout the whole Asia in span of many centuries, so details would obviously depend on particular construction.

Generally, from it's nature, it's stiff, nicely "isolating" armor, which is practical mostly for protecting torso - hard to make decently working elements for limbs & stuff.

They were found mostly in dry steppe areas, as far as I understand one of main hypothetical reasons is that small, mostly organic cords used to connect the plates were obviously not very resistant to damp conditions.

[Fhaolan]

I have a question about lammelar armor. How does it compare to other armor in terms of protection, weight and ease of wear, and construction?

Lammelar can be made of multiple different materials. I've seen historical wooden, bone, and steel lammelar armours, and people have made leather ones as well (although I'm not convinced as to the historical accuracy of the leather ones). On average though, lammelar is stiffer than people usually think, and due to the overlap needed in the plates, quite a bit heavier. The smaller the plates, the higher the end weight tends to be (unless the plates are correspondingly thinner, and therefore weaker) as the ratio between overlaped plate to exposed plate increases. Because of this, I've found that lamilar tends to be lighter than scale, but still heavier than a solid breastplate.

Construction-wise, lammelar is just like scale and rivited mail in that it's tedious to churn out all the pieces and attach them together. Not particulary difficult, just tedious. Again, the smaller the plates the more tedious is gets.

The lammelar I dealt with was stiff enough so that the entire torso could stand up on it's own without any other support. While it could flex, it was definitely not as flexible as mail or scale. There is an advantage to this though. It distributes the force of a blow over a large area, it will deform under that blow, but it will also flex back again rather than staying compressed as a solid breastplate would. There will likely be individual plates that stay deformed, of course.

[Autolykos]

So I still don't understand how you intend to detect heat. Vacuum is an excellent insulator, so things in vacuum give off heat through radiation only. Radiating heat can be tricky to do. In fact one of the big problems with lasers (rail guns) and cannons will be heat dissipation, and large radiating surfaces would have to be employed. Which someone else already noted would be a weak spot that can be targeted.

If an object isn't efficiently radiating heat how do you detect it thermally in vacuum? Is infrared sensitive enough?
Any hot object is emitting heat as thermal radiation, period. It's the law, specifically the Stefan-Boltzmann Law*:
P=epsilon*sigma*A*T^4
(P is the emitted power, epsilon is the emissivity or "blackness" of the object, sigma is a natural constant, A is the object's effective area and T is the absolute temperature). The emissivity won't get much lower than 1% (for polished silver), and even then a hot object (say, at 500K) still radiates plenty.

As for how other systems have trouble radiating enough heat, the emissivity won't get higher than one, either. You can get a little more excess heat off by increasing the effective area, but that's only so much. If you need to get rid of excess energy in the Megawatt (or even Gigawatt) range, that's a completely different game from a hot cannonball (and doing this will make you a *really* bright target).

*EDIT: I don't know how firm you are with physics, but what this tells us in essence is that the amount of energy you are radiating in a fixed time mainly depends on your temperature, and there are precious few other things you can do about (and they have very little effect).

[Hawkfrost000]

New thread time?

DM

[Knaight]

Well past. Apparently we are on page 52.

Probably time to drop the futuristic weaponry discussion as well, considering the thread title.

[Thiel]

I've gone ahead and made a new one. It can be found here (http://www.giantitp.com/forums/showthread.php?p=11941948#post11941948)

[Fortinbras]

In terms of historical accuracy, what are some of the better viking movies?

[endoperez]

In terms of historical accuracy, what are some of the better viking movies?

We're on a thread 9 now:

http://www.giantitp.com/forums/showthread.php?t=217159