Sci-fi Weapons, Vehicles and Equipment

Salvage operations would be also pretty likely. Even if the thing is dead there might be some worthwhile information on the computers.

In a somewhat realistic environment, the cost of going to Saturn to salvage some data off a computer is going to be, almost literally, astronomical.

We have vast quantities of space junk around our planet right now and it's still vastly cheaper to simply launch more crap.

Salvage operations aren't really going to be a thing outside very special circumstances, and it's not going to happen on a grand scale when those conditions are met. A rocket crew desperate for spare parts is more likely to go and salvage than a trillion-dollar company.

Not unless you have people living there around Saturn.

In the setting being discussed, there is enough interplanetary travel to have dozens or hundreds of orbital stations built around Saturn. It's a lot more believable that people might engage in salvage operations under such conditions.

Propulsion technology is at the heart of any discussion about sci-fi settings. It is literally the most important factor to consider for verisimilitude.

1. If people are still using expendable chemical rockets, then there will not be any interplanetary colonization or commerce. It's just too expensive.
2. If we have reusable chemical rockets, such as Starship or something similar, coupled with in-situ resource utilization, then colonization and commerce become feasible, but spacecraft are still committed to fixed routes and schedules and it will take months or years to get anywhere. There will be no diversions or daring rescues. Available delta-V is the harshest mistress of all. It will always be easier to send a new spacecraft somewhere than to repair or rebuild on-site.
3. If we have nuclear drives, such as nuclear-thermal (fission/fusion), nuclear salt water, nuclear pulse, and so on, then it becomes possible to make rapid transits without worrying so much about launch windows and low-energy orbits. Travel times are cut substantially and you can start talking about interplanetary commutes. However, it is still impractical to wage war in such a setting because of delta-V constraints and the relative fragility of spacecraft.
4. Exotic propulsion systems like antimatter, Kugelblitz, and so on, would open up casual interplanetary travel and the possibility of warfare. They would also make interstellar travel feasible within human lifetimes. Interstellar war is still a no-go.
5. Fictional systems like the Epstein drive work because they get much higher thrust than real life nuclear-thermal fusion and achieve extremely unrealistic fuel efficiencies. These can also give you casual interplanetary travel and the potential for warfare.
6. FTL is required for any sort of casual interstellar travel.

Edited by Fighteer on May 13th 2022 at 1:58:05 PM

Sometimes you can have more than one system, too. Say one for conventional movement and one FTL. This is how it is in my setting, fusion scramjets (which, depending on the design, can also operate as airburning hydrogen engines) and photon drives for things that need delta-v, but wormholes for things that can be done without delta-v including FTL.

Sure, that's fair. It's also the case that anything more exotic than chemical rockets is unlikely to be operable within a planetary atmosphere (or near settlements in the case of airless worlds) because of radiation and other forms of high-energy pollution. So you'd need one propulsion system to get to orbit and a separate system to travel between planets.

There are also alternatives to chemical propulsion for getting to and from orbit, such as space elevators and skyhooks. These won't completely eliminate the need for rockets but can substantially lower the energy costs for individual launches.

Thus we get dedicated spacecraft for traveling around solar systems, "shuttles" for landing and departures from planets, and probably a different type of ship for interplanetary travel if that's possible in a setting.

Of course, if your FTL works within a solar system and isn't extremely disruptive (or energy intensive), then it might replace normal propulsion methods for getting to most places.

Edit: I forgot one obvious outlier: antigravity. If you have gravity control, then you can play God with physics and normal energy constraints for getting places stop mattering.

Edited by Fighteer on May 13th 2022 at 2:33:52 PM

And if the FTL can change your velocity rather than merely teleport you, as many fictional (and perhaps many techniques based on general relativity). Otherwise it will be constrained to work between orbits of equivalent energy, even if they are located in different galaxies. Great to get from Earth to TRAPPIST-1, useless for getting from Earth to the Moon.

Right, you definitely need that. If FTL doesn't change momentum, you could hop over to another solar system and then fly right out of it because your relative velocity is too large.

Edited by Fighteer on May 13th 2022 at 2:40:31 PM

Solar systems aren't necessarily stationary to each other. Bare minimum, stars are orbiting the galactic core at different speeds. On the flip side, you could jump some distance "ahead" of the destination and then accelerate to a reasonable intercept speed. You could even use the main star for a gravity boost.

So a question I did ask a while ago regarding the Space Fighter trope: Does it make sense in a setting where instantaneous momentum-conserving teleportation with an accuracy of a the size of a spacecraft (say a few tens of kilometres) is possible? The idea being that it's momentum-conserving thus delta-v or g-forces aren't an issue. And by randomly jumping around a target while you attack it you have a chance to hit them, without the target having time to respond since you are gone by the moment they are firing back.

Arguably, this works out against the space fighter because the same technology can be used to attack it's base or carrier.

Some sort of teleport spam attack? I like the concept. The main question for any use of the Space Fighter trope, however, is not whether the propulsion technology allows it but why you would choose that kind of platform over some other, more capable one.

The larger the ship, the more powerful the weaponry it can mount, the more endurance it has while deployed, the more damage it can sustain, and so on. If they can blink around the battlefield without needing to expend delta-V, then maneuverability ceases to be a factor, so that eliminates one of the presumed advantages of fighters.

Also, if you can do that with combat craft, you could do it with munitions, and teleporting a nuke inside a target's intercept range would be a pretty effective attack.

Remember, the reason that fighters are used in modern day militaries is that they are small enough to land on and take off from carriers and military airfields and can perform high-G maneuvers to evade fire. They can also independently engage over-the-horizon targets. None of these factors really applies in space.

Edited by Fighteer on May 13th 2022 at 5:30:05 AM

If you are popping in and out of 3-D space to take your shots, then I would assume you would want to use the largest weapon platform, which can fire the most attacks simultaneously. A battleship, not a fighter.

Too large a platform and the risk of collisions due to navigation inaccuracies increases. Also, even if counterfire is largely ineffective it is not literally zero percent effective, and a bigger attack craft is an easier target. And larger spacecraft cost more to build.

Then go with Fighteer's other idea and just teleport the missiles.

Well, you said that teleportation accuracy is "a few tens of kilometers". That's a pretty big error rate when talking about close combat. The risk of accidentally hitting something is pretty large, so to avoid that I'd want to jump no closer than 1000 km or so to any given target. At such a distance, the distinction between a capital ship and a fighter in terms of weapons accuracy is trivial.

Well, yeah, but accuracy isn't that much of a concern here. The principal effect of the navigation errors is that they prohibit things like teleporting into enemy craft.

Now of course you can automatize the fighter, but I don't think that, say, a Space Bayraktar is that distinct from a manned spacecraft and would consider both a kind of space fighter.

You are suggesting that a fighter-size craft could avoid enemy fire more easily than a capital craft. This doesn't make sense given your parameters. At the necessary range to avoid accidental telefragging, the physical size of the ship is fairly unimportant, and if both can teleport with the same "cooldown", maneuverability is not a factor.

And yes, automating these weapons would make far more sense than putting people in them, so if you can achieve more economical results with a swarm of smaller, automated ships than with a few crewed capital ships, that could be a reason to use "fighters"... or drones, more properly.

Edited by Fighteer on May 14th 2022 at 9:40:00 AM

Well, except that smaller craft are less expensive to replace...

But unrelated to the above, in my setting you need to navigate in diverse space environments. Sometimes you depart from low gravity worlds and sometimes from high gravity worlds. More importantly you often work around neutron stars or other dangerous environments where you need lots of shielding against radiation.

The solution that spacefarers have found are various types of carrier spacecraft - reusable boosters to get spacecraft to orbit and between orbits, and asteroids with engines or highly eccentric orbits that serve to provide shielding against radiation in systems that need it. Specialization is also often used but since it's pretty crippling, also often avoided.

Edited by SeptimusHeap on May 14th 2022 at 11:58:30 AM

Same reasons why militaries prefer or use other smaller craft on land, in the air or at sea despite the technology of today allowing for 100,000+ ton nuclear warhead slugging, missile spamming naval battleships or multi-engine flying fortresses of aircraft bristling with missiles and guns or tanks so big and powerful that houses are smaller than they are.

They’re cheaper, they get the job done, they’re less risky to lose, they fit the doctrine in play of whoever uses them, you can have more of them, they’re harder to detect, a lot of reasons.

Space isn’t the kind of place where logical reasons like ship costs magically disappear and suddenly everything always no matter what favors Bigger Is Better.

Edited by MajorTom on May 14th 2022 at 7:28:17 AM

I don't really see how this teleport scenario would lead to fighters. Missiles make more sense than fighters by default, this is just going to make missiles even better.

Regarding ship size, that depends. For a straight engagement, size doesn't really impact performance and you'd want the biggest weapons platform you can field. But a battleship is way overkill for policing actions, for instance.

The Lucas critique applies to militaries too - missiles can be dodged or intercepted, especially if they all come from the same direction or from a distance. So there is a reason to have one launch platform attack from all directions and over short distances, especially if you have resource constraints. Now the launch platform does not have to be manned - it can also be an attack drone á la Bayraktar TB2 or even something fully automated - but I don't think that is an essential difference from a fighter.

The traditional concept of a Space Fighter generally includes a living pilot and the capacity for Old-School Dogfighting. It also requires that they return to base. Drones don't have to have these features. If they are simply expendable missile-launching platforms, they can be super cheap.

>The Lucas critique applies to militaries too - missiles can be dodged or intercepted, especially if they all come from the same direction or from a distance. So there is a reason to have one launch platform attack from all directions and over short distances, especially if you have resource constraints

I really don't follow. Missiles can be intercepted or dodged, but so can fighters. A weapons platform can also shoot missiles and thus attack (via missiles) from multiple directions. Nothing about this is done better by fighters. A missile especially is going to outperform literally everything in it's engine class because unlike everything else, it needs to go only in one direction.

The only place a space fighter might make sense, is if we have military bases on gravity wells, like our natural Moon.

And even then, I'd question it.

Just follow rule of cool. You'll be fine.

Edited by Draedi on May 18th 2022 at 4:01:55 AM