Are space fighters really impossible in realistic Sci Fi?

[essenmein]

As far as I know the actual routine is to go on humvees and/or APCs and assign tanks as/if necessary.

But the point is, that while it might not be wise to bring a .22 to a tank fight, it might be useful to have something big (maybe: a tank) to support small arms.

Yeah depending on what your operational goal is, infantry with tank support, or is it a full armored division that's engaging?

I was looking at it from the perspective of if you've got a modern tank battle going on, that is tank vs tank, then infantry is at best track lubricant.

Are there even infantry carry-able weapons that could knock out say M1A2?

Maybe its a scale thing, if the ships are 3km+, maybe a "fighter" in that context is a 200m vessel, not a 15m fighter plane like we see in sci fi.

 

[Nik_2213]

A small ship may haul a lot of missiles, and such missiles may 'mung' their emissions etc to resemble ship-killers...

While their 'flight profile' matches, you got to 'Honour The Threat'.

It is also practicable to mask a small ship, using eg cryo-cooled hydrogen as an expendable heat-sink and/or aligning radiators away from possible threat axis.

Small ships are also handy for softer targets, 'hit and run' operations. Such attrition must divert materiel from 'Grand Fleet' operations. Like the way Ironclads found themselves vulnerable to small, nimble torpedo boats. Fast Torpedo Boat Destroyers were required to chase off such. And, yes, those Destroyers could be equipped with torpedoes, become the bane of bigger ships' stately battle-lines. So, Cruisers got the job of killing enemy Destroyers. Then Battle-Cruisers to sink those Cruisers, provide support for the big ships, learn they were too flimsy for slug-fests...

An analogy from the days of sail; IIRC, one question of an aspiring Lieutenant placed his fallen Captain's damaged ship- of- the -line on a lee shore, in a full gale. What to do ??

Modern version attacks a 'Carrier Group' with a dozen shore-launched cruise missiles.
A dozen ? No problemo...
Four salvos follow.
Fifty ? Yeah, yeah...
Eight salvos follow...
Oops...

 

[essenmein]

Yeah its always a numbers game, I can shoot down one missile! ok how about two then?

Its a guessing game of how many missiles per hr the attacker can field and how many you can shoot down.

The enemy in my story is basically employing the over whelming numbers tactic, so even though "our" weapons and ships are more advanced, there is a point where they just cannot keep up. Its quite asymmetrical in that context. The protagonists at first don't realize they are essentially fighting a guerilla war and they are the guerilla...

 

[Nik_2213]

"Are there even infantry carry-able weapons that could knock out say M1A2 ?"

IIRC, yes. Tanks are vulnerable to precision top-attack. So, instead of launching a TOW or equivalent missile on a 'line of sight', a jeep-mounted mortar or whatever could loft loitering smart-bombs over the target. Either the 'smarts' auto-identify the tank, stoop and wreck its engine, or the PBI's 'designator' lasers tag juicy prey...

 

[BWV]

What about the structural integrity to hold a kilometers-long ship together under conventional acceleration? It seems that hyper-drive capable ships must be limited to accelerations that are a small fraction of a gee.

Unless your artificial gravity generators double as tractor beams, providing for structural rigidity without needing a structure.

The Earth's tallest buildings are nearly a kilometer in height and do just fine under a constant 1G acceleration

 

[jbriggs444]

The Earth's tallest buildings are nearly a kilometer in height and do just fine under a constant 1G acceleration

Yes, that was the standard I was judging against. One gee sustained constant thrust by a earthly building of less than one kilometer. So presumably less in a spaceship of multiple kilometers. Though I am not expert on the limiting constraints that apply in the two cases.

 

[Nik_2213]

"The Earth's tallest buildings are nearly a kilometre in height and do just fine under a constant 1G acceleration"

{Cough} Straw Man ? They also have mass dampers, base isolation etc, sway in the wind and suffer badly should their foundations shift even slightly.

A more appropriate analogy may be bulk-carriers, ranging from ore ships to VLCCs. They're yay big, they don't like changing direction, they don't like sea-states that affect different parts of the ship in different ways. Even when everything was built to best practice, they may still crack where modules meet. Many design lessons continue to be bought in blood...

For a big spaceship, you may see the equivalent of the old steam-ships with their umpteen boilers, stacks and engines. Yes, it is one (1) ship, but a closer look will show a dozen near-independent power sections flying in rigid formation...

 

[essenmein]

Another thing to consider is that buildings put all their mass on the foundation, which is loosely similar to a rocket. However if you have a more distributed drive then the structural situation changes quite dramatically. You now no longer have the last part that is holding all the weight.

 

[BWV]

"The Earth's tallest buildings are nearly a kilometre in height and do just fine under a constant 1G acceleration"

{Cough} Straw Man ? They also have mass dampers, base isolation etc, sway in the wind and suffer badly should their foundations shift even slightly.

A more appropriate analogy may be bulk-carriers, ranging from ore ships to VLCCs. They're yay big, they don't like changing direction, they don't like sea-states that affect different parts of the ship in different ways. Even when everything was built to best practice, they may still crack where modules meet. Many design lessons continue to be bought in blood...

For a big spaceship, you may see the equivalent of the old steam-ships with their umpteen boilers, stacks and engines. Yes, it is one (1) ship, but a closer look will show a dozen near-independent power sections flying in rigid formation...

Right - unlike a tall building, a spacecraft under 1G acceleration faces no other forces so it can be much longer. Bulk carriers are a terrible comparison because they face all the forces of the ocean at different angles than the direction of motion. A spacecraft only needs 1G acceleration in one direction because presumably to decelerate it would just stop the drive, rotate 180 degrees, then re-ignite it. BTW he Japanese have viable, if uneconomic plans, for a four kilometer skyscraper. These arent my original ideas - read Alistair Reynolds - IMO the best living SF writer (who has a PhD in Astrophysics and worked professionally in the field before he quit to write full time).

 

[jbriggs444]

On the other hand, a typical tall building will be built for office space. You can manage height because you only have to support people, desks, chairs, file cabinets, soda machines and microwave ovens. In the case at hand, we are told that the spacecraft size is based on the need for great heaping gobs of unimaginable power. One would expect them to be pretty dense.

Hmmm, offhand, I'm not sure how feasible it is to generate great heaping gobs of unimaginable power using only radiative cooling and a radiating surface that only scales as the square of the linear dimension. Maybe these ships are pretty light after all. Or maybe they get cooling by cyclically heaving thermally hot beads away and then pulling them back with artificial gravity tractor beams.

You kill such ships by blowing away their cooling clouds.

 

[essenmein]

On the other hand, a typical tall building will be built for office space. You can manage height because you only have to support people, desks, chairs, file cabinets, soda machines and microwave ovens. In the case at hand, we are told that the spacecraft size is based on the need for great heaping gobs of unimaginable power. One would expect them to be pretty dense.

Hmmm, offhand, I'm not sure how feasible it is to generate great heaping gobs of unimaginable power using only radiative cooling and a radiating surface that only scales as the square of the linear dimension. Maybe these ships are pretty light after all. Or maybe they get cooling by cyclically heaving thermally hot beads away and then pulling them back with artificial gravity tractor beams.

You kill such ships by blowing away their cooling clouds.

Actually you'd be surprised how much heat you can dissipate with a black body radiator into space (~0K). Its a delta t^4 relationship. The orange white glowing things on these ships are not drive exhaust or "rockets", but cooling plates. Keep in mind the area for cooling increases proportionally with ship size.

For perspective, to keep 10m2 at ~1300C in space requires about 3MW.

 

[Rive]

Yeah depending on what your operational goal is, infantry with tank support, or is it a full armored division that's engaging?

Well, one thing is sure: while fighting for superiority is done with the big ones, everything else is for the cheapest available option. Even in space, there will be something what will be considered cheap and (relatively) expendable => fighter.
Yeah, you are right: it might be a bit bigger than usual. But maybe not - maybe that 200m 'figher' will have some smaller drones...

 

[essenmein]

Well, one thing is sure: while fighting for superiority is done with the big ones, everything else is for the cheapest available option. Even in space, there will be something what will be considered cheap and (relatively) expendable => fighter.
Yeah, you are right: it might be a bit bigger than usual. But maybe not - maybe that 200m 'figher' will have some smaller drones...

Cost does weigh in, in my case though its mass/energy cost not $$$, at the end of the day a $ really is an energy value (potential work? lol).

The thing I wanted to work through is that it doesn't matter how cheap if it logically/strategically doesn't work. I didn't want to have these little pew pew fighters blowing up these 3km ships which are meant to be hard to kill by something its own size, because why then would you build the big ships?

Watched a lot of docos on tank development (interesting stuff humans do in times of need) You either have tanks that can kill the other tank, or, the shells bounce off, in which case you went to essentially zero chance of a kill before you get killed (note pre sabot rounds..). In any reasonable scenario if 3km ship can take a hit or two from another 3km ship, then even a kamikaze 15m fighter is like a bug splat on a windscreen.

Note also, these ships do not have the bridge any where near any outside surface, all deep within the hull.

 

[Rive]

it logically/strategically doesn't work.

vs.

Small ships are also handy for softer targets, 'hit and run' operations. Such attrition must divert materiel from 'Grand Fleet' operations. Like the way Ironclads found themselves vulnerable to small, nimble torpedo boats. Fast Torpedo Boat Destroyers were required to chase off such. And, yes, those Destroyers could be equipped with torpedoes, become the bane of bigger ships' stately battle-lines. So, Cruisers got the job of killing enemy Destroyers. Then Battle-Cruisers to sink those Cruisers, provide support for the big ships, learn they were too flimsy for slug-fests...

Those 3km gigants are supposed to be the big ones, but they will still need a support fleet of smaller ships. And those smaller ships will be good candidates for operations where those 3km gigants are not necessary, but that means they will also need some even smaller ships for support... And so on.

I just can't see a scenario where something really small is NOT needed at the end of the line.

 

[essenmein]

vs.Those 3km gigants are supposed to be the big ones, but they will still need a support fleet of smaller ships. And those smaller ships will be good candidates for operations where those 3km gigants are not necessary, but that means they will also need some even smaller ships for support... And so on.

I just can't see a scenario where something really small is NOT needed at the end of the line.

That would be true against another human like enemy, however that is not the case with the main protagonist. The type of enemy has to be considered. These aliens in the story are very alien that operate at a different scale, temperature, energy source (ie food), in the story they don't even make an attempt to communicate, they don't care, to them we are equivalent to what insects are to us. Our first encounter is "oh look there is a weird hot alien ship, oh what's tha..." (boom exploration ship gone). There is no boarding party, there is no capturing ships, there is no small ship. There is only survive or die against extremely hostile extremely large alien things. And if we happen to survive, they just keep pouring in ships because they now know where we are (in that instance at least).

The size of our ships is simple A10 thunderbolt math, here is the gun or guns we need to kill these things, now wrap an engine and air frame around it. Go.

In that context to me at least, fighters don't make sense.

I don't want to go to far into it, but the big ships we have are not human origin, we find alien tech from one side of an ancient war and accidentally inherit the responsibility that comes learning about that and knowing the mere existence of this alien force. For the time being the only thing keeping us from total annihilation/extinction is that they simply don't know where Earth is.

Then later in the story when us humans meet other carbon based creatures not too dissimilar from us, is when we realize that ummm, all our weapons are so large we can't even fire them near your planets atmosphere for fear of the collateral damage... One xray laser blast is created with mega tons of anti matter explosion yield as the pump source. Every time one gun barrel fires its like tzar bombas going off.

To me that's actually a annoyance I have with a lot of scifi, the energy scales of the weapons. Say you have a rail gun, but if you want to give your projectile say 10kt yeild equivalent in kinetic energy, they you need to put that 10kt in there on launch. I think that would make rail guns much larger than people think...

 

[essenmein]

Thinking about it, even without special aliens, I don't think fighter craft make sense in even in a near - medium future human context.

Absolutely for support, escort, and other ancillary tasks, but I doubt maned small craft would be much good against a equal foe on a front line space war.

Reasons:
1) weapon capacity is too small and a pilot limits evasive manouvers due to g force limits, drones would be more sensible.
2) since its unlikely something like a full startrek cloak is realistic across all EM they would be detectable.
3) small craft = small armour means CIWS type systems would render them useless, this is essentially already the case today hence all the grumbling about the F35 having lower dog fight capability due to long range weapons. No reason to think that would change in favour of the fighter in the future, if any thing it would only go more against it.
4) We can already shoot down a high speed projectiles, hence I think even missiles would have limited use, unless they are more used as recoiless high speed mass round.

Now this hinges on the following:
Actual battle ships and larger craft are in play, basically I don't think carrier style fleets make as much sense in space as they do on the ocean since once away from planets its essentially a direct fire exchange, carriers work because they can send their planes over the horizon and themselves remain out of direct fire range (ie minimal armour requirements). They would not have that luxury in space.

Since in space its direct fire combat the entire time, any small craft would just get chewed up by a wall of high speed projectiles, no dodging around geographic features. Leaving the large ships lobbing larger hunks of mass at each other.

I also don't think lasers make much sense, unless the photons themselves are high energy (eg xray/gamma), a chunky xray pulse is just a neat way of transferring the energy of a nuclear blast to a targeted point. Nukes in space are just a blink of xray/gamma, its not until that light hits some mass that bad things happen.

But I think mass drivers is the most realist space weapon, after pondering it for a while, there is no way I can think of to effectively stop v high speed mass (like 2-3% speed of light) unless you invoke the magic of shields.

 

[Rive]

not the case with the main protagonist.

No one can beat a story plot, that's sure.

But story plots better to have some touch of realities regarding resource-effectiveness.
OK, it is entirely possible even to shave with a splitting axe. There are even competitions for this, as far as I know.
But can you imagine somebody who would try to do everything with that same splitting axe?

 

[BTA]

I think there is a basic flaw in this line of thinking, the original question is wrong. Use of conventional planet based warfare and technology would not be used off planet. Our concepts of combat originate in "face to face", "within visual range" and "line of sight" situations. The way we think about attack and defense is not applicable to space combat. We are a ways from being able to imagine space combat in realistic terms, even between ourselves.

And, there are too many variables about what the situation could be. Lasers or other energy beam weapons could easily be counteracted, especially when a spaceship has to be hardy enough to be in space. What field effect shields would a spaceship have? A spaceship would have to be immune or highly resistant to micro-meteorites effectively moving at faster than light speeds, example: the meteorite is moving toward the spaceship at 3/4 the speed of light and the spaceship is moving toward the meteorite at 3/4 the speed of light for an effective 1.5 times the speed of light speed of impact.

It takes energy to project an energy beam, shooting multiple beams to cover all possible places the target could be would be a huge, ineffective and inefficient, waste. Shooting bullets or other projectiles would be much more of a waste - you had to make the projectiles and haul them around on the spaceship: you had to use more fuel and other resources to carry around projectiles. Where does your spaceship get more fuel, etc when it runs low?

And, whatever form of attack you use, that reveals your location, your intent and the extent of your offensive capabilities. Your enemy now knows where you are, that you are hostile and what you can do.

Destroy or disarm the point of origin of the spaceship. Make peace with the enemy. Hack their programs. Be seen as either too powerful or not rich enough to be worth conquering. Or, be seen as too useful or not useful enough to disrupt.

 

[essenmein]

No one can beat a story plot, that's sure.

But story plots better to have some touch of realities regarding resource-effectiveness.
OK, it is entirely possible even to shave with a splitting axe. There are even competitions for this, as far as I know.
But can you imagine somebody who would try to do everything with that same splitting axe?

Heh, that's the thing about storys, you're in control :)

Resource effectiveness is something that's important though, and after just looking at the scales of things that happen in space, and more precisely the scales of energy that occur, its my feeling that human scale, ie what we think is big, and what we think is a "WMD" I think needs a re think when talking galactic terms. Then the question is if you can manipulate much larger energy or power quantities, what could then be "realistic".

The chicxulub impactor, is a great example to compare what we call a "WMD" and what is actually a WMD. Based on those scales our biggest nuke is barely a firecracker. And that was a relatively small rock, ~15km in dia.

 

[essenmein]

I think there is a basic flaw in this line of thinking, the original question is wrong. Use of conventional planet based warfare and technology would not be used off planet. Our concepts of combat originate in "face to face", "within visual range" and "line of sight" situations. The way we think about attack and defense is not applicable to space combat. We are a ways from being able to imagine space combat in realistic terms, even between ourselves.

And, there are too many variables about what the situation could be. Lasers or other energy beam weapons could easily be counteracted, especially when a spaceship has to be hardy enough to be in space. What field effect shields would a spaceship have? A spaceship would have to be immune or highly resistant to micro-meteorites effectively moving at faster than light speeds, example: the meteorite is moving toward the spaceship at 3/4 the speed of light and the spaceship is moving toward the meteorite at 3/4 the speed of light for an effective 1.5 times the speed of light speed of impact.

It takes energy to project an energy beam, shooting multiple beams to cover all possible places the target could be would be a huge, ineffective and inefficient, waste. Shooting bullets or other projectiles would be much more of a waste - you had to make the projectiles and haul them around on the spaceship: you had to use more fuel and other resources to carry around projectiles. Where does your spaceship get more fuel, etc when it runs low?

And, whatever form of attack you use, that reveals your location, your intent and the extent of your offensive capabilities. Your enemy now knows where you are, that you are hostile and what you can do.

Destroy or disarm the point of origin of the spaceship. Make peace with the enemy. Hack their programs. Be seen as either too powerful or not rich enough to be worth conquering. Or, be seen as too useful or not useful enough to disrupt.

First since the OP was talking about realistic scifi, relativity is real and your 1.5x light speed effective impact is not correct. However the micro meteor thing is a real problem and basically some sort of composite armour is all I can think of to stop them.

I also don't see a mechanism that we know about at the moment that would allow this "shield" thing to work, but please, if I'm wrong here let me know lol.

Then re combat since distances are extremely large in space, and hitting things from those large distances involves needing to essentially look into the future to see where you need to shoot since even light can take significant amounts of time. That makes me think that if two foes are aiming to shoot at each other and actually do anything other than create more micro meteors that will find a planet in a few 100k years or some random blinks of light for a future civilisation to wonder about, they will have to get close to each other to be effective.

 

[BTA]

If you are willing to be unrealistic enough to have unlimited amounts of energy to shoot lasers at all possible places the other spaceship(s) could be... Then, why not have ESP, mind assault, destroy or interfere with the smallest but most essential parts of their technology (remotely frying the transistors in the power regulator of their engine, using telekinesis or pyrokinesis, teleportation, creation of space/time warps, creation of black holes (microscopic but precisely placed would do the job), fission/fusion of their flux capacitor or dilithium crystals, astral/ethereal projection, severing their spiritual silver cord, psychic domination, projected illusions/delusions, spells, demons, entities from other dimensions,

 

[essenmein]

Because large amounts of energy are realistic, and they are large to us but absolutely normal in space, we see them happening all over the galaxy, yet we've never seen telekinesis.

A star quake on a neutron star creates an (I think) xray pulse that would take our sun several hundred thousand years to produce an equivalent amount of energy. Energy scales in space are so obscene we're going to run out of zeros pretty quickly if we keep using the tinyest of tiny unit for energy, the joule.

 

[essenmein]

Just as a reference:
"On December 27, 2004, several satellites and telescopes from around the world detected an explosion on the surface of SGR 1806-20, a neutron star 50,000 light years away. The resulting flash of energy -- which lasted only a tenth of a second -- released more energy than the Sun emits in 150,000 years."

 

[BTA]

"Because large amounts of energy are realistic..." spaceship shoots multiple xray pulses (from their miniature artificially created neutron star power source) covering most of the locations the enemy spaceship could be by the time those pulses arrive. Enemy spaceship detects incoming xray pulses because the pulses create ripples in the spacetime continuum and those ripples affect quantum entanglements, and takes evasive action. My credibility of space combat is going through catastrophic failure event.

large amounts of energy coming from a small spaceship, no. We are still trying to figure out how mantis shrimp pack so much punch. If neutron star xray pulses were an available technology, there would be an effective countermeasure and combat itself would be obsolete. Present day technology includes smart missiles, computer viruses, EMP bombs, nuclear, chemical and biological weapons. Present day technology makes beating our chest, roaring and stamping our feet.. obsolete.

 

[essenmein]

Perhaps this is an issue of definition.

To me "realistic" means it fits within our known laws of physics. Since the laws of physics to my knowledge haven't changed in millions of years or since the beginning of our universe really, nuclear power and space flight for example have always been possible within those laws, before we even existed as a species. Its just taken us this long to figure out the how. So its not inconceivable that more engineering and knowledge wouldn't give us the how for much much larger energy sources and all the possibilities that opens up. We know how to make anti matter, and we know how to make fusion, we just haven't perfected it yet, and we haven't scaled it up yet, but its not unrealistic that we could.

The only reason I raised the neutron star as an example is simply to demonstrate that absolutely ridiculous energy levels are real things that exist naturally and that us as humans think we've done some big things when in reality we haven't done any thing big at all, our planet looks big to us, but you can fit 1.3 million of them inside our sun, and our sun is a small star as far as stars go.

Will we as a species ever get to where we can release a 100k years worth of output from our sun in fractions of a second? highly unlikely, but those energy levels themselves are not fictitious, where as telekinesis ESP etc are fictitious, so IMO its a straw man argument to say well if large energy is realistic then so must be ghosts. We've seen large energy sources, we orbit one, but there is no evidence for demons.

 

[Rive]

the scales of things

Sure. If a race has 3km big fighters, then ... well, I've read stories (still Sci-Fi) where the body of an intelligent specie was big as a planet, so those fighters are still acceptable somehow.

But no figters at all? No way.

 

[essenmein]

Sure. If a race has 3km big fighters, then ... well, I've read stories (still Sci-Fi) where the body of an intelligent specie was big as a planet, so those fighters are still acceptable somehow.

But no figters at all? No way.

Well you could call any flying thing with a weapon "fighter", in which case any space battle would be basically impossible without them. Need to define the term "fighter" better!

Although when faced with planet sized intelligence, those 3km things are likely the size torpedoes you need :D

Or is that a missile? not certain there is a functional difference between torpedo and missile in space?

 

[Rive]

Need to define the term "fighter" better!

Well, maybe we can define it as the smallest manned vehicle of any fleet?

not certain there is a functional difference between torpedo and missile in space?

With reference to space games, usually a torpedo is slower and beefier, while missiles are fast and agile

 

[hmmm27]

In a space battle, most munitions wouldn't be primarily destructive ; they'd be chaffers, decoys and EM pulse, and lots and lots of disposable sensors. Everything stealthed against reflection and cooled to MBR.

 

[Lren Zvsm]

I agree but just for info 10G is survivable for humans. I think it's the limit imposed on Red Bull air racers.

For about how long? Humans would not survive for long on a planet with 10x Earth's gravity, would they?