Saturday, December 26, 2009

Science, Technology and Space Combat


First let me wish everyone a very happy Boxing Day and hope you celebrate it in good company.


Today's thoughts are about space combat as depicted in Science Fiction.

Some SF Warships are set in a universe or science that is so different from today that no meaningful scientific analysis of their technology is possible. I wrote a short story featuring such a ship in my short story 'In Command' in Baens' anthology 'Transhuman'. My story consentrated on the ship's captain, the only living person on the giant warship unless you count the AI.

http://www.amazon.co.uk/Transhuman-Mark-L-Van-Name/dp/1416555234

Iain Banks has written a whole series of brilliant novels about The Culture, a space-dwelling civilisation based around giant AI controlled ships that use a science so high that it makes electronics look like a stone chisel.

http://www.iain-banks.net/

I play games with toy soldiers and have had fun with many space combat games. The picture above is of an Imperium battleship from the Warhammer 40K universe.

http://www.games-workshop.com

These drift through the currents of a 'warp' inhabited by psychic daemons, guided by three eyed navigators who can 'see' into warpspace. Otherwise, they are huge WWI battleships with tens of thousands of crew hauling on chains to load the guns.

Other stories look at near-future space warships. TV and films almost always get the science utterly wrong. Space has no resistance. You apply thrust to increase acceleration in a specific direction and that is all you can do to speed up, slow down or change direction. In gravity well, where all near-future space combat is likely to happen, the overwhelming force is gravity so all movement is along orbital tracks. Given that craft will have limited fuel supplies then spaceships cannot go anywhere and will move from place to place along predictable orbital solutions. A reasonable analogy is with sailing ships that tracked along wind routes. The predictability of navigation means that defensive mines and battler stations are a real possibility.

There is no shock wave in space so blast weapons are useless. The best ship killers will be bullets fired from something resembling a machine gun. Shells with proximity fuses, that fragment into flak would work. Missiles that are small spacecraft would also be a possibility. They would probably look like balls with two offset motors on booms to control course change and would fire their engines sporadically.

Lasers might be useful as a sniper device but the energy needed to power a ship killer would be prohibitive. Maybe a one shot weapon powered by a preloaded capacitor/battery would work.

Nukes would be great because of the radiation (not blast) that they generate.

The ideal warship would have no crew. People don't belong in space and a ridiculous percentgage of mass and energy of a warship design would be needed to protect them just from space itself, let alone enemy action. The mathematical nature of space warfare makes it ideal for computers, communication links to 'pilots' being used for strategic decisions, like changing the orbital approach.

Last but not least, electronic warfare, detection (active and passive) and stealth, will be overridingly important. The first side to detect and plot the track of an enemy is likely to be the victor. An anology is with submarine warfare.

1. So what would a near future space ship be like? How would you design one?

Here are a couple of websites to stimulate the little grey cells:
http://gizmodo.com/5426453/the-physics-of-space-battles
http://www.projectrho.com/rocket/index.html

Finally, for fun, let's hear your version of a fantasy/ultra-technology space warship?

13 comments:

RJ_CruzeJr said...

For a near-future warship, I'd probably go with an unmanned vehicle (get rid of the fragile bit of humanity, along with making more volume available for reaction mass and/or weaponry). For it's main drive, to get into position, use an ion thruster, but for quick thrusting and maneuvering (evasive action, rapid redeployment, whatever) good old chemical boosters and thrusters.

Also it'd be an insanely stealthy design. After all, you can make it as weird-shaped as you like without having to worry about aerodynamics. Though, I'm guessing it'd look pretty freakin' ugly -- like it was designed by Clarence "Kelly" Johnson and H.P. Lovecraft after the second bottle of tequila. It flies in the vacuum of space blowing stuff up; it doesn't need to be pretty.

Of course, the downside is that the stealth would only work when it's not maneuvering. It'd probably operate like a submarine: it uses its drives to get into position and then goes silent (I remember a Ben Bova story along those lines...)

Weaponry would be a mix of missiles and kinetic kill devices (I call them "guns"), along with a small laser for ranging and blinding optical sensors.

Then the other intangibles like: it'd be a maintenance nightmare, constantly going off-line for all sorts of sundry reasons; the logistics of operating it will be ten times what the bean counters said it would be; and in combat it'll do stupid stuff like prioritize the DirecTV satellite as its prime threat rather than the two dozen incoming missiles, or, in a fit of electronic pique, it'll fire off its entire warload at Vega for no apparent reason then self-destruct.

As for my ultra tech warship -- I'm thinking something like Space Battleship Yamato, except a hundred times cooler looking, and decked out with kill-o-zaps, hellbores, and its own Caribou Coffee franchise! Now that's what I'm talkin' about!

Kate said...

I'd guess near-future unmanned with a dedicated link to VR techs who do the actual guidance and management - because it's going to be a long while before we even get close to human pattern-matching to detect hostile action, but viable VR communications links should be available a lot sooner.

That of course requires a manned ship somewhere not far from the unmanned one.

I'd say a spherical design (maximum capacity per unit surface area, plus no blind spots for weaponry), firing absolutely everything available. Laser fire for distance work, guidable missiles with nuclear warheads (since they'll be slow enough that they'll be avoidable except at ludicrously close range). EMP pulse weapons to take out control systems.

Each manned vessel would probably control a lot of unmanned ones.

For far future where it's indistinguishable from fantasy in the practical sense, I'd say probably still spherical or elliptical for the maximum volume to surface area (especially manned vessels) with a central core that provides some kind of simulated gravity and - probably more important - inertial damping so that the squishy human-like bodies inside stay at the same velocity as the spaceship.

Unmanned warships could get a whole lot weirder: some kind of core engine with a framework studded with all kinds of weaponry (these wouldn't be able to enter atmosphere and would probably be used for orbital defense and the like). I'd see lasers remaining the workhorse for distance weaponry because without faster than light anything laser fire would be undetectable until it hit. Ditto EMP weapons, which could be combined with laser fire.

For closer in, any kind of fast-moving physical material would work, although nuclear would have the added bonus of radiation issues.

If lightspeed remains a 'hard' barrier, and some kind of shortcut like wormholes happens, ships that cross those would have to be designed to handle whatever dangers are posed there. With something like wormholes with known entry/exit points, control of the entry/exit points would become the main focus for military control - unless of course the military in question belongs to an ideological "destroy the unbelievers" culture that just slaughters anything in its way.

Short-short version - it'll probably leave our best guesses in the dust and be weirder than anything we could think of - but that shouldn't stop us trying.

Francis Turner said...

I think a big problem with combat spaecraft will be heat. Firstly combat weapons are bound to involve significant energy release at launch and unless we come up with 100% efficient launchers a good deal of the energy will be heat. Since theres no convection and limited conduction (conduction within the craft only) a lot of work is going to have to go into radiative heat dissipation because otherwise the second or third shot will overheat the launcher.

Radiating all this heat will however make the launching craft standout to infrared detectors so that makes the idea of stealth a bit tricky too.

Chris McMahon said...

I've often though near-future space combat might be a little like the early piracy in the Caribbean. It wasn't so much the huge broadsides and gun blazing, with the ships going down at the end. The early pirates used to overhaul other ships just for the resources they needed, like coils of rope and barrels of tar. Chests of gold were few and far between.

In space, with such huge distances and scarce resources, I would think early combat is more likely to be over supplies of oxygen and fuel - and you would not want to damage the other ship too much.

matapam said...

Near term – say, while acceleration and endurance limits mean that we have to pay attention to gravity, no force fields or inertial dampers, no FTL communications. I think you'd see battleships that might be technically mobile, but are for most engagement lengths slow enough that they're bases, not ships. Heavily coated with rubble to stop lasers and radiation, Possibly with multiple shock absorber braced compartments for the live persons controlling the various unmanned weaponry that are doing the flying around out there. Multiple marconi cages, multiple, swappable, replaceable antennae. Optical cables wherever possible to reduce the amount of EMP charge that could be induced. Perhaps a lot of surface mounted, aimable mirrors. Keep them angled so that lasers shot from the direction of the approaching Bad Guys is reflected back at them, or missiles they have launched.

The actual weaponry would be semi autonomous, when given the go codes. The operators would mostly be in charge of battlefield tactics, picking among scenarios, and sending the changes to various clumps of thousands of variously kinetic, explosive, radiation weapons.

A lot of the weaponry you'd be hastily designing would depend on the attacker's weapons and defense. If it's on par with ours, minimal problem. Fighting aliens who do have force fields, heavy lasers, particle and plasma weapons and the acceleration and the engine endurance to ignore gravity wells will be a whole 'nother problem.

For them you start out with lots of junk in orbit, all beeping and tweeting, and hope destroying all of them gives your spy sats enough time to gather some data on their capacities. Especially the capacities of their shields. FOF signals to get through it would be nice. You have to figure out how to 'touch' them. Spectral analysis of their hull material, for some disbursed nanobots to eat, either after they slowly leak through the shields, or you counterfeit an FOF response and get something through that will disperse the nanos.

John Lambshead said...

Dear RJ

I think the analogy between near future space warships and submarines is close except for the lack of crew in the former.

John

John Lambshead said...

Dear Kate

I suspect that technological advances will mean the manned 'ship' is on a planet or a space station in close orbit.

John

John Lambshead said...

dear Chris

I see a problem in boarding actions with matching vectors on the target vessel. It is likely to require an enormous amoount of fuel.
John

John Lambshead said...

Dear Francis

Good point. I had forgotton heat. Another reason to have no crew. Suddenly infra-red guided missiles look attractive as a weapon.

John

John Lambshead said...

Dear Pam

I think the problem with large slow-manoeuvering battleships is that they would be horribly vulnerable to kinetic energy bolts (i.e. bullets) and nukes.

John

matapam said...

With missiles, lasers, particle beams and whatever they come up with next, any massive ship is going to be at a serious maneuvering disadvantage.

Hence the use of heavily shielded constructs as bases for control of more mobile, unmanned weaponry. The base itself, whether it can maneuver or not, or is down on a planet, will always be a prime target. Hence the rubbled exterior. It'll absorb some kinetic impact, as well as conceal the location of redundant control centers, with shock absorbers as well as more technically advanced shielding. With nukes, you protect against the EMP by using as much optical cable as possible, especially for long runs, and layered conducting and insulating containers. I've heard these referred to as both marconi cages and faraday cages. The sheer mass of rocky material will help protect against radiation, as well as passing along the heat more slowly, and some heat and blast effects being mitigated by the physical removal of the rubble. AKA, hot, molten radioactive debris flying off into space - and not affecting the working ship parts at all.

Mind you, a flying gravel heap isn't sexy.

I'd much druther be flying a sleek and stealthy ship that can land at need, and slip deep into enemy territory to report on troop movements. Any fight against unknowns (Aliens, time or dimension traveling humans etc) is going to require massive efforts at data collection.

nyrath said...

Well, there ain't no stealth in space. Refer to the Atomic Rocket website, under "Detection"

@Francis Turner: yes, getting rid of the waste heat from your weapons requires huge radiators. Trouble is, radiators are pathetically vulnerable to hostile weapons fire. This is one of the major problems.

And huge battleships are not necessarily ponderous. The important thing is thrust to mass ratio. It is possible to give a huge ship such large engines that it can run rings around a fighter. Spacecraft are NOT wet navy vessels.

For more details, read the Atomic Rocket site, all the chapters that start with "Space War:"

Chris McMahon said...

Hi, John. True - but the same problem would apply to any space engagement/manoeuvre in any case.