So I've been toying around with a scifi setting and I'm thinking about what kind of equipment the Space Marines in it would use. Mainly talking about heavy equipment like vehicles, armor, aircraft, and artillery, but small arms speculation is welcome as well. These guys are meant to be based on the space marines from Aliens, not the 40k ones. So they're basically just 80s era US level in terms of technological development. The only exception to this is interstellar travel, which is teleportation based and only works for interstellar travel due to imprecision. So its not relevant for getting stuff to and from space. That has to be done the old fashioned way. As such, weight is an important factor. Right now I'm leaning towards them using modular systems which can be field assembled into whatever they need. Engines, wheels, and various frame components that can be welded or bolted together to make anything from jeeps to armored cars. And the armor is made from polymer fibers like kevlar or nylon shaped and hardened for whatever kind of armor panel they need. For example they could take an engine, some frames, and some wheels, and make a jeep. Or they could take two engines, some extra wheels, and shape some armor to make something like a Cadillac gage commando.
>>65109812>So they're basically just 80s era US level in terms of technological development. The only exception to this is interstellar travelWell, "normal" space travel too anon. You can't do an orbital ship anything like that picture without some sort of magic drive. The propellant mass fraction on something like the Falcon 9 for example is about 95%, ie, 95% of the weight at launch is fuel. About 1% is rocket and that leaves ~4% to get to orbit (these numbers are expended, it's lower with reuse). A rocket sending 17.5 tons to orbit weights about 550 tons at launch. Such is the tyranny of the rocket equation.So you're probably going to need to compromise on that one too, if you want to go really hard SF it could be interesting for sure but would get pretty autistic or you're going to have really dig into the effects (like, any torch drive almost by definition is going to double as a pretty destructive weapon for anything on the business end). How you decide this will then feed into what is realistic elsewhere down the stack. You could fire up KSP if you want to just play with stuff in a fun way vs paper. Depends on what sort of setting feel you're after.
>>65109812Also thinking about fuel. This isn't some sci fi setting with super sci fi batteries, so they're limited to the current limitations of electric vehicles at maximum and probably less. That means lots of heavy batteries that get significantly less mileage than a comparable amount of weight in gasoline. Plus the risk of malfunction, high maintenance cost, and risk of fires. I also doubt the viability of electric powered armored vehicles. My first thought is to make them use the same fuel as their spacecraft, but the spacecraft all use fission rockets for propulsion because its the highest thrust and most weight efficient method of propulsion. So there's no liquid oxygen and hydrogen to run their land vehicles on. My next thought is to have them produce petro chemicals synthetically on site. There are ways to do it via carbon capture or chemically without needing crude oil or large amounts of biomass. Its not energy efficient, but wasting energy is hardly an issue in wartime. They could just setup some nuclear reactors to power the production of the fuel. That however sounds like it'd take a lot of infrastructure and setup, so it would be impractical for smaller scale operations that don't involve long term occupation, and of course doesn't explain how they would bootstrap that occupation to begin with.
>>65109812Getting stuff down FROM space is easy, and can be done in mass. Drop pods are "no big deal" relatively speaking, if the planet has an atmosphere you can dump most of your relative velocity into that and relatively small retrorockets or engines+flight will do for the rest. If your setting has main supply planets with space elevators or launch lifts or emag launch or sky fountains as infrastructure, and/or asteroid belt mining/orbital construction for all the big stuff, then I think you can do a fairly good setting where basically you never have stuff come back up, only people, maybe a few valuable specimens or whatever. You just send stuff down and then abandon it when the mission is over. So you have big jump-drive drop ships that hold in orbit and provide orbital fire support and supply drops.>>65109880>nuclear salt water rocketOk, so yeah this is a relatively obtainable torch drive and does give you the delta-v for some real mass up. But you're basically flying on an enormous plume of high level radioactive waste, like a million chernobyls going off behind you. So maybe that's your emergency escape from an alien infested planet but you probably don't ever want to come back, or at least not with serious protective kit. And don't want to use it anywhere that's intended to get colonized or anything either.
>>65109880>so they're limited to the current limitations of electric vehicles at maximumWhich are increasing rapidly fwiw. You don't necessarily need super scifi, theoretical limit of a lithium air battery is close to fossil fuel but a motor can be near perfectly efficient whereas ICE is like 20-30% energy-to-wheel efficiency. So batteries can store 1/3 the power and still be fine. Torque is also very very good. I don't think electric is a stretch here, in such a world they'd have sunk way more money into it decades earlier.>Plus the risk of malfunction, high maintenance cost, and risk of firesAll less then conventional, so that's not an issue.>syngasThe infra to do this at scale is more magic tech then electric + a compact nuclear reactor or three, maybe some RTGs depending on environment to go with stuff, that can be dropped down for power/heat.So yeah, I think your plan here is big space-only jump drive carriers of various classes and support ships that bring in all your land stuff. Small operations send down some vehicles and enough consumables for whatever the expected operation time is, and something to get the people back off. When the mission is over you either leave stuff intact for later in some cover, or destroy it from orbit after leaving it. Maybe have a saltwater drive thing for emergencies or in certain situations. In a full scale occupation you're aiming to set up multiple bases around the planet, taking advantage of your relative mobility to come down where they can't do an immediate response, and/or doing kinetic bombardment strikes to take out shit like ICBMs. You can have fun figuring out what your FOBs and so on look like, but probably want a nuke plant and at a minimum some equipment that can give you water and depending on situation air too right off. Ammo is better to just bring in, very high density for value.
>>65109849I was just using that as an op image. I'm already not planning on anything like that.What I was thinking at the moment is them using blue origin style space planes carry conventional aircraft into atmosphere. These are dedicated exospheric craft that exist exclusively to bring more normal jet aircraft to a height they can function from. I do have a bit of a cheat written into the setting though. There exists a form of antigravity, but its incredibly rare, difficult, and expensive to produce. Its treated like nuclear weapons were during the cold war, in that its an incredibly tightly guarded secret that the existing powers don't want people knowing. If you have it, you're a major galactic power, and Earth is a regional power at best. If Earth did manage to build some antigravity devices, they'd be incredibly valuable strategic assets. Probably large LHD type ships which can briefly hang in upper atmosphere to deposit aircraft. Alongside some smaller rocket assisted craft built for retrieving special operations groups to planetary surfaces. I guess for anything they aren't willing to risk their irreplaceable antigrav shuttles for could be done by dropping fuel on the planet from orbit to refuel their spacecraft. Or they could just use nuclear rockets for takeoff, which would fuck the environment, but why should that matter, its not their home planet.
>>65109812>Right now I'm leaning towards them using modular systems which can be field assembled into whatever they need. Engines, wheels, and various frame components that can be welded or bolted together to make anything from jeeps to armored cars. And the armor is made from polymer fibers like kevlar or nylon shaped and hardened for whatever kind of armor panel they need. For example they could take an engine, some frames, and some wheels, and make a jeep. Or they could take two engines, some extra wheels, and shape some armor to make something like a Cadillac gage commando.This probably takes things too far and owuld result in all kinds of reliability issues and engineering problems. A better approach would be to have a couple barebones plattforms in different sizes, with modular kits enabling them to fulfill a wide variety of roles with just 3-4 different-sized plattforms.Basically the Boxers' idea taken up to eleven.
>>65109898>So maybe that's your emergency escape from an alien infested planet but you probably don't ever want to come back, or at least not with serious protective kit.What about on planets with either no atmosphere or an already uninhabitable one? Say like Mars or a less hot and acidic version of Venus. Anyways I could see that being in their war doctrine for total galactic war. It would fit with the cold war in space theme I'm going for. It'd be a bit like all those tactical nukes they had parked in Germany in case the Soviets tried crossing the border.
>>65109898What about planets with lower gravity than Earth? What's the threshold where chemical powered craft can come and go from them practically?
>>65109974>What's the threshold where chemical powered craft can come and go from them practically?The exact number depends on the specifics of your chemical engine. At moon levels (~16% of earth's 1g) it's trivial, that's why something like Apollo could work. At Mars levels (~40%) you need a real rocket but you can do it SSTO in a fairly straight forward manner, like with SpaceX the SuperHeavy booster is only required on Earth, the upperstage Starship by itself should be sufficient to get from Mars surface to orbit.Though of course, you need the fuel, so "practical" is going to also depend on what infrastructure is practical. Again, at low enough gravity you don't need any, even simple hypergolics or solids you bring down will do it. Then there's a level where you need some cryogenics for practical major lift, but that could be doable from, like, a "stage 2" base if the planet has sufficient volatiles to work with. And then maybe you have solid rockets as your emergency escape, that's pretty straight forward for a spacefaring power. Of course from a story perspective rockets and fuel infra are tempting explodey targets for whatever you're fighting so that feeds into tactical considerations.If you're doing space based construction and mining however, then you've potentially got a LOT of "regular" mass to work with (stuff like uranium is still going to be rare) without any super high tech. So you can potentially lean on that with the exception of the magic FTL. I'm not sure if you really need antigravity even to do a cool story.One big challenge though is to explain why tech doesn't rapidly advance further. You can come up with a cool setting of 70s/80s space tech in a world where the US/USSR space race went a little differently and more seriously. That gives a few decades before computers get good and make humans obsolete. But if you want more then a few decades that'll take some thinking.
>>65109924>Which are increasing rapidly fwiw. In real life, yes, but I said current limits are a maximum. This is a retrofuturist setting where electronics technology stagnated hard in the early 80s. The only hard limit I placed for this is the minimum size of transistors reaching their limit in the late 70s. But other technological limitations are needed to keep the aesthetic. Like LCD displays being much more primitive to keep CRTs in use, or magnetic tape storage remaining the main method of data storage. That doesn't mean EVs need to nerfed to 80s levels, but they do need to fit within the other limits enough and be less popular than gas cars on Earth to keep the aesthetic. Perhaps I could explain the prevalence of gas powered cars as the result of oil company lobbying and marketing to make people stay dependent on them even after the proliferation of nuclear power.
>>65109965That sounds like a lot of added weight. Especially if those vehicles are made of conventional steel and composite materials. Maybe if they could get it down to two basic frame and engine sets, with plenty of interchangeable parts between them and a modular design.So you have a light frame that can either be an unarmored light truck for utility work, an unarmored troop transport, or a lightly armored truck like the humvee. Then you have a heavy frame that can be a heavy transport truck, an APC, a mobile howitzer, or an assault gun depending on configuration. They'd use aluminum frames and that field reconfigurable armor. Either as polymer fiber that can be shaped as needed then hardened with resin, or premade hard panels than can be bolted on and are interchangeable.
>>65110023My explanation is the the physical limit on the size of transistors before they become physically impossible. We're approaching that limit now, which is why computers aren't advancing nearly as fast as they used to. The story would just move the upper limit of moore's law to the transistor density of something like an 8088. That keeps space from being automated fully and maintains the cool aesthetic. A bit like Fallout making transistors a dead end technology.
Even if precise adjustment of warp coordinates is difficult, surely it's possible to warp cargo from a planet's surface into orbit?
Ok assuming they're using electric vehicles and dumping things on the surface with the expectation that most of the heavy stuff if going to stay there. What would their air power look like?Obviously they have orbital support to rely on. But would that completely replace air power? Wouldn't they still need atmospheric transport, and wouldn't they also need close in weapon support? And what if they can't rely on constant 24/7 orbital support?Not having gas would limit their aircraft options wouldn't it?
>>65110094No, this sort of thing can get you "in the solar system". Once you're there you have to rely on physical movement. Besides, the amount of radiation it puts off would make it impractical to do on a planet's surface.
>>65110059I dont see the niche where the lego block method provides meaningful advantages. If I'm dropping a group of men for a sudden surprise surgical strike, the absolute last thing I want is them to be stuck assembling vehicles. In a large scale deployment that same question applies, except its probably more vital they get them active given the likelihood the opponent has equivalents ready to go. Once you start talking about mounting howitzers and whatnot I think youd be better off figuring out how to flatpack something like a M56 and just go with that instead
>>65110298The vehicles would be assembled on the flight over or in orbit depending on how long you're there. I do see your point though.
What about technicals?Instead of bringing all these different vehicles, you just adopt a modular truck system. You can have a flet bed, a picked, a closed roof transport. Could mount any number of guns to it. Mortars, machineguns, grenade launchers, autocanons, maybe even small howitzers or direct fire artillery, not really big stuff, but maybe your pack howitzers can also be attached to a truck if you want to. Bolt on armor panels (similar to that one skeletonized truck system the army tried a few years ago) for a quick and dirty APC, with these panels also doubling as portable barricades or components of prefab structures. You could still have tanks and dedicated armor or spgs, but you only pack those things on the ship if you think you'll need them. Otherwise you just keep a small fleet of trucks and a various different equipment to attach to them.
>>65110345And since you know these things are likely going to get left behind or destroyed to prevent capture anyways, it works better with it being cheap trucks instead of more expensive dedicated vehicles.
>>65110039So, BattleTech without the magic heat-expansion fusion drives that allow for a 100,000T ship to expend <5T of fuel each day on a constant 1G burn.
>>65110419No mechs either, and no phone company, and no space feudalism, and aliens exist. So really not like Battletech at all beyond it being retrofuturist. I'd say it has more in common with Alien's setting, but without the horror.
>>65109812i'll paste some notes i took for a similar headcannon scenario---Room temperature supercapacitors, allowing for even more power delivery and output. It would allow for lasers, coilguns, much better computer (miniaturized auto targeting devices) due to less/no heat, magnetic levitation for trains and other logistics craft, and magnetic shields for spacecraft (personal shields too?).Supercapacitors could deliver a lot of instant power for laser and small railguns. Proposed design: portable railgun powered by a backpack containing a large battery and a supercapacitor.Solid state batteries would enable powered exoskeletons and HUDs and wearable sensors, radios, IFF, etc.---1/?
>>65112470Cased telescoped ammunition has volume and pressure advantages. Reduced volume, due to the projectile not protruding from the casing. This has logistical benefits. Pressure can be higher as the cases are fully supported in the chamber, allowing one to increase pressures without blowing out the part that lies unsupported over the feed ramp.Feeding can be in the form of a rising or rotating chamber mechanism with push through feed or eject (textron/ares design), or by adapting modern chambers and using traditional ejectors and extractors (textron patent, unbuilt prototype). The moving chamber design is theoretically simpler in mechanical terms and reduces heat buildup, but comes with ergonomic problems.The casings will be made of advanced polymers in most standard issue cases. Polymer is the lightest practical material that you can use, and by being a thermal insulator, prevents heat from heating the chamber much better than metallic cases, though it concentrates heat in the barrel throat. It is also easy, quick and cheap to make. If using an extractor for ejection, durability could be an issue; there is a risk of torn rims. For this we will solve by using a metallic base, like True Velocity does in real life. Heavy duty applications (very high rates of fire, very powerful charges) would use CT casings made of alloys such as magnesium alloys and beryllium-copper alloys. 2/?
>>65112470>>65112476materials: gamma-titanium-aluminide.Cited characteristics (AI summary):- lighter than titanium, which itself is about half as heavy as steel- VERY strong- corrosion resistant (especially important in other worlds)- can survive up to 800-1000 C temperatures before failure- abundant minerals- today it's only used in specialized contexts due to energy, tooling and processing costs (vacuum processing), but these would be trivial in a scifi scenario with asteroid/exoplanet mining and unlimited fusion energythis could be the common material replacing steel. Weight can be further reduced with 3d printing of equipment, allowing for man portable autocannons and other weapons that are too heavy currently. 3/?
>>65112470>>65112476>>65112486Weapon barrels made of this alloy would be lighter and have greater heat and corrosion resistance than current chrome-molybdenum-steel barrels, though they would have worse heat dissipation. This can be overcome though. One could use forced air cooling, liquid cooling (enabled by lighterweight weapons), 3dprinted ooling channels, or just swapping the barrel more often/the entire gun (viable if you have effectively unlimited minerals and orbital delivery). Advanced alloys make railguns viable too, but would be expensive and special purpose
>>65109812I like Morningstar's vibe. The retro aesthetic is due to the socioeconomics, science has clearly progressed and the cheap crap given to the disposable soldiers is similar to our tech level with some quirks like 6.8mm caseless in helical mag AR10s and ceramic/polyethylene body armor. Rockets land vertically and use NASA's radiators and magnetic radiation shielding.
>>65112470>>65112476>>65112486>>65112495Weapon technologies- Electrical firing, instead of firing pins - less vibrations, more accuracy - form factor now only limited by chamber and bolt but not by hammer and trigger linakge - instant firing, not even the few milliseconds of firing pin travel - perfectly crisp triggers, good for bullpups, heavy weapons, can be placed literally anywhere to allow for new ergonomic designs - stacked bullet volley guns! Metalstorm -perfect for integration with combat bots (fire by thought, no finger actiom)- Integrated batteries to power attachments (fit into stock or grip) - ammo counters - thermal/night scopes that don't have to carry their own batteries - fire control systems: target recognition, fire when chance of hit is guaranteed, optimal fire rate control - sensors to diagnose things like barrel temperature - biometric/credential lock on weapons to avoid treason!!- Smart link sight systems that project reticle and/or weapon POV into HUD for close range shooting, more intuitive and quicker than aiming, though sight will still be present for longer range aimed shots- Ammo counters either on the weapon or on magazines. Triviality of data collection and manufacturing capacity could mean weapon and ammo design tailored specifically for each world and threat.
>>65112470>>65112476>>65112486>>65112495>>65112502## Heads up display- enabled by electronics being so cheap- Features: - compass on top of FOV - IFF: icon above friendlies, maybe even "skeleton" display - works through networked gear - or maybe through image recognition - color coded edge highlight (already exists) - live map - navigation map if available - indoors floorplan if available - simple motion sensor/pointer to nearby friendlies if nothing is available - 3D pings - aimed by weapon smartlink and fire control system - virtual reticle at center of FOV to aim pings? - follow eye tracking with neural link??? - status of squad (alive/dead/wounded) - orders and dispatches can appear as a banner - weapon reticle / POV as picture in picture if weapon is equipped - weapon ammo count/temperature/status if linked and equipped with sensor - picture in picture image or video feed - environmental conditionsetc
one day all of /k/ will be 100% vidya-guns threads if the europeans are weeded out or range banned.there is almost no reason for europeans to need to post here
>>65112470>Supercapacitors>Lasers>Exoskeletons>ShieldsI wouldn't really call it a similar scenariio. Humanity in this setting is decidedly not in possession of any of that. Not that it doesn't exist, just that they lack the technology to produce it in a usable form in the quantities needed to adopt it. All the big kids on the galactic block have it, and they don't.
>>65112498too grimdark, but I do like space capitalism aesthetic. I was generally going for a more grounded tonally speaking version of 80s America with its theming. The tech is hard limited though because its specifically meant to be humanity being technological inferior to its neighbors, in addition to selling the aesthetic.
