Future Warfare

[Mirannan]

Spiegal - I agree completely about tokamaks. One more problem with them is that they would probably create more radioactive waste than a fission reactor does; the hot neutrons released by the reactions normally (so far) used are quite good at making all manner of structural materials radioactive.

One of the problems with a fusion reactor which emits a lot of its energy as neutrons is that the only way we know of to extract the energy is thermal. Which introduces a heck of a lot of waste in the conversion.

Again incidentally, it may be the case that p/B11 is technically a fission reaction, as the products are smaller than one of the reactants and also more numerous. Which is only of interest to people who like to nitpick.

 

[JonH]

Google "focus fusion".

Thanks for this steer. I'd never come across DPF before. It's an interesting technology.

 

[Bowler1]

Narrow your mind and think like a soldier.

Well said.


I think tactics would decide on stealth or all guns blazing. Planets and orbits, moons and rocky asteroid fields could be used to hide behind. Superior fire power is always going to help, but I think the first to draw and shoot on target could be more useful. Single ships will operate differently to a fleet, as will different classes of ships. Sneaky little spy ships or big mother ships with support vessels, each will operate differently. Lots to think about and all open to technology too, who is faster, cloaking, communications and lots more to change the mix. My poor yellow head is spinning.

 

[Mirannan]

An interesting point that I've only recently considered is that DPF fusion is a pulsed process; the dense plasma in the name only exists for a brief period. Which probably means that a DPF fusion reactor would have a characteristic sound when operating. Further to that, the probable way of controlling the power output would be by altering the frequency of the pulses - so the sound would change according to power level.

Unfortunately, I think DPF fusion is unlikely to get to market even if it's feasible. Clean, cheap power in small (supply for a house, maybe?) units would be something that vested energy interests would do just about anything to stop. Huge headlines along the lines of "RECKLESS ENERGY COMPANY WANTS A NUCLEAR REACTOR IN EVERY HOUSE!!!" along with rad danger sigils and the like.

 

[Tower75]

One thing that I can see happening, if space combat every happens, would be like the Helfort Wars books:

Ships are about 5,000,000 KMs away from each other and are travelling at 500,000 kms a second, so you have to work out firing solutions, shoot a cone of thousands of rail gun slugs to try and intercept the ship, like shooting bird-shot at a bird , then following it up with missiles.

Once that opportunity is passed however, you won't get another one, you're moving too fast to do anything about it.

 

[JonH]

An interesting point that I've only recently considered is that DPF fusion is a pulsed process; the dense plasma in the name only exists for a brief period. Which probably means that a DPF fusion reactor would have a characteristic sound when operating. Further to that, the probable way of controlling the power output would be by altering the frequency of the pulses - so the sound would change according to power level.

Unfortunately, I think DPF fusion is unlikely to get to market even if it's feasible. Clean, cheap power in small (supply for a house, maybe?) units would be something that vested energy interests would do just about anything to stop. Huge headlines along the lines of "RECKLESS ENERGY COMPANY WANTS A NUCLEAR REACTOR IN EVERY HOUSE!!!" along with rad danger sigils and the like.

From what I read, I think each reactor will have a characteristic frequency and output level. If you pulse too infrequently, the deposition level will be too high, if you pulse at too high a rate, you'll overheat, so there'll be an optimum rate which will be all the cooling can bear, and that will give you a particular power output, and sound.

If the prototype reactors are expected to run at 5 MW and fit in a room, I doubt they'll go in every home, at least until they miniaturize them further. 1,500 of them would supply the entire UK. And why would you want one in the house? I certainly haven't the space for it -- even at a tenth of the size, and why should I bother with maintenance and refuelling? It would be like having individual water-treatment works in every house: technically possible, but undesirable.

If it works I think it will be introduced as a module of a larger-scale nuclear reactor, so you might get twenty of them to create a 1GW power station, then you could cycle maintenance, and run at 95% capacity. Whether community-level reactors would be allowed in cities is debatable. Would you want a new-design nuclear reactor at the end of your street?

Back on topic, I think DPF could be used as the basis of a ship-mounted X-ray cannon. Especially as the power comes out naturally in the form of X-rays pulses. (And that should get it funding, too.)

 

[Mirannan]

JonH - That's the point, isn't it? The phrase "nuclear reactor" is scary precisely because the only ones we have, fission reactors, are effing dangerous. A DPF fusion reactor wouldn't be; it might slag down, but is unlikely to blow up (and even if it does it's going to be on chemical explosion scale, not nuclear) and won't, under any circumstances, spew out radioactive isotopes. I can easily imagine one of these in the bottom of an apartment block or at the end of the street, or running an 18-wheeler.

Regarding the OP, one advantage of DPF power is that the power generation could be distributed rather than having one big point of failure in the middle of the ship. Which, for a warship, is a very good thing indeed.

And regarding the issue of having a power plant at the end of the street; well, many people have a substation (which is moderately dangerous) at the end of the street and somewhat fewer have propane gas depots or petrol stations not much further away. Either of which can and do blow up if proper safety procedures are not adhered to. The obstacles to widely distributed DPF power units, if they can be got to work, will be vested interests and Luddism - not any real risk.

 

[Vertigo]

I once read something that really is a horror. Imagine an interstellar war. Now imagine 100-ton autonomous ramscoop drones with an acceleration of double-digit Gs, with a few lightyears of runup and which stop boosting (except for course correction) a few light-days from target.

Double digit acceleration from a ram scoop (drone or otherwise) is highly unlikely. In fact the biggest criticism levelled against ram scoops is the doubt that the engine will ever be able to generate more thrust than the drag of the scoop. I personally think that should be possible but I very much doubt if you'll ever get a ram scoop up to 1g never mind double digit g's. Interestingly enough they are potentially capable of much higher rates of deceleration than acceleration.

I think the most likely scenario for space combat will be fleet actions with the opposing sides passing each other so fast that only computers will stand a chance of targeting the enemy and most of the battle time will be spent turning for another pass. Think days of manoeuvring for each millisecond pass.

 

[Sapheron]

Do you need to worry about drag in space? Surely accelerating one thing is pretty much the same as any other of similar mass in a vacuum without any major gravity?

 

[Vertigo]

ram scoops work by putting out a huge 'scoop' either physical or magnetic which collects all the tiny amounts of matter in space and uses them as reaction mass. The act of catching them is what creates the drag. The question is purely whether one can throw them out the back faster than the speed you caught them. If you can then your aggregate force is positive and you have acceleration. Note that you have to get up to a pretty high speed first before the ram scoop becomes practical. And once up to high speeds it does not take a lot of matter in space to create drag. And believe me if you have double digit g's acceleration on an interstellar voyage you are going to get up to seriously high speeds (relativistic even) and you are going to have some serious drag.

 

[Toby Frost]

I agree with a lot of what's been said about spaceships, but I'm not sure about the idea of high-speed "jousting" as the ships zip past one another at incredible speed. For one thing, space is so big that I'm not sure ships would often stray into one another's sensor range by accident. For another, I suspect that the majority of warfare would occur at points of strategic importance, such as the orbit of a major planet. In those situations, I would expect ships to slow down to a combat speed and do all the stealthy stuff already discussed.

 

[Darkchild130]

Yeah, I'm not into the high speed jousting either. As a hit and run tactic sure,both if both sides wanted to legitimately fight each other they would slow down, it would take an age to wheel round for an attack pass otherwise.

Also, you have to consider that fleets may be assaulting a planetary defence fleet etc with plans to launch an invasion force of aforementioned strategic targets.They would need to slow down to drop troops, and get into decent covering positions to defend against counter attack as they did so. Same goes for shipyards, sensitive installations, larger scale observation posts and the like. Basically anything you don't want obliterated needs to be captured, and you can't capture anything when you're space jousting.

 

[Bowler1]

I agree with a lot of what's been said about spaceships, but I'm not sure about the idea of high-speed "jousting" as the ships zip past one another at incredible speed. For one thing, space is so big that I'm not sure ships would often stray into one another's sensor range by accident. For another, I suspect that the majority of warfare would occur at points of strategic importance, such as the orbit of a major planet. In those situations, I would expect ships to slow down to a combat speed and do all the stealthy stuff already discussed.

I do think strategic points too. Think battle of Midway as an example. The Americans knew the Japanize fleet was on way, but waited for it to arrive. A planet or other rocky/gas/sunny points should give the defender a slight advantage, which could be the make or break in a fight.

 

[Spiegal]

Hey guys what if... there were no battles in deep space. At all.

If they detected each other they just reported it in to wherever their nearest outpost was and carried on their merry old way.

The greatest ship based weapon would be shaking your fist through a porthole at the enemy.

 

[Darkchild130]

Human nature says no, then rams a tank sized railgun slug up your arse for shaking your fist at it.

 

[Toby Frost]

If you're flying fast enough, the railgun shell won't connect and you probably might as well just shake your fist for all the good it would do. A ship would probably would just keep on going at immense speed and warn the nearest Point of Strategic Importance of potential trouble, unless slowing down to fight in the middle of nowhere was somehow necessary. "Station A, I detected a blip in sector XYZ - you might want to fire up your defence grid, just in case."

 

[Darkchild130]

If you're flying fast enough you wouldn't shake your fist either. Or in other words, don't take my comment literally I'm making a point. People will find ways and reasons to fight as long as there are people.

 

[Spiegal]

Human nature says no, then rams a tank sized railgun slug up your arse for shaking your fist at it.

Ouch, depleted uranium up the tailpipe. Can't we all just get along?


On a side note, while it's obvious that railguns are a pretty safe bet for hypothetical starship weaponry but what about active defenses? I'm thinking of things like the Phalanx CIWS on sea vessels or Quick Kill on tanks.

I would presume something that would be able to deflect the projectile rather than destroy it would be preferable. I don't know what sounds worse, a shell the size of a house or a hundred the size of a car...

I also remember reading somewhere about giant nets being deployed in space to destroy projectiles passing through them. The wires are loaded with explosive charges that detonate when something passes through to create a shield thousands of kilometres across.

 

[Tower75]

Ouch, depleted uranium up the tailpipe. Can't we all just get along?


On a side note, while it's obvious that railguns are a pretty safe bet for hypothetical starship weaponry but what about active defenses? I'm thinking of things like the Phalanx CIWS on sea vessels or Quick Kill on tanks.

I would presume something that would be able to deflect the projectile rather than destroy it would be preferable. I don't know what sounds worse, a shell the size of a house or a hundred the size of a car...

I also remember reading somewhere about giant nets being deployed in space to destroy projectiles passing through them. The wires are loaded with explosive charges that detonate when something passes through to create a shield thousands of kilometres across.

I assume the first point-defence will be anti-missiles missiles.

Then a type of chaff/decoy thing

Then CIWS systems

Then finally explosive armour to deflect impacts.

I don't belive a railgun slug needs to be any bigger than a conventional bullet. When it moves that fast, a bullet-sized slug would causes a hella bang and a big hole.

 

[Darkchild130]

A combo of everything mentioned in the last two posts for defences. I genuinely think space combat is going to take a "golf bag" approach for offensive and defensive weaponry. With it being so ridiculously dangerous in such a hostile environment, any other mentality is tantamount to suicide.

The railgun slug does need to be a certain size, because mass. Especially if you are chasing another vessel moving at similar speeds, or one in a defensive roll to maximise deflection.