I'm Tired of Stupidly Big Sci-Fi Ships 

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The Dune ships are an interesting counter example, since mass and size matter little, but there's a limited number of Navigators to move the ships, meaning you want to be able to move as much as possible in each jumps.

For the 40k part : Servitors are not counted as "crew members" or "passengers" ,if it was the case ,the number of personnel would be considerably higher.

There is weird and kind of interesting bit in regards to the ships in 40k in the book series 'twice dead king' where a necron gets on board one of those stupidly sized imperial battle ships wondering about the massive crew capacity and then realized that everything is done by hand and he looks at a gigantic anti ship cannon being loaded manually by thousands of slaves and crewmen and there are even mutated sub species of human who've founded their own tribal civilization in the bowls of the ship. I found it extremely interesting in it's sheer insanity.

Something good to point out with crew sizes is automation. You can feasibly have an entire ship with a crew of 10 people, if everything is automated. The US carriers have massive crews because it gives them a lot of flexibility, it is generally cheaper/easier than heavy automation, and most of the carriers were designed literally decades ago. They can accomplish this because they have a large system of naval supply networks that makes it very cheap to supply, feed, and transport those sailors. In space, each person on board requires not just food, but air, water, waste reprocessing facilities, and many other elements that just aren't needed on a naval ship. While this is obviously a flawed example, each ISS astronaut is estimated to cost more than $100,000 per hour while on board. While a huge amount of this price is because everything has to be brought from the surface, space is expensive. These costs heavily incentivize automating everything you possibly can, because a robot is drastically cheaper than a person in space.

I always liked how in Isacc Asimov's Foundation's Edge novel, the latest and most advanced ships were notably tiny compared to previous ships, and required hardly any crew due to advanced engines, computers and other tech.

I think the size=power thing is at least partially a holdover from the Age of Sail, where the firepower of a ship was pretty much only proportional to the number of cannons, and more ship=more cannons.

Another factor to consider for massive ships is maintenance and docking facilities. A smaller-size ship can be repaired, maintained and upgraded at any of dozens or even hundreds of facilities, whereas one that's exceptionally large may only have one or two dedicated spacedocks capable of accommodating it.

The easiest answer to the ship-size-to-crew-ratio issue is to say that most of the ship is taken up by giant reactors or solid superstructure or refrigerators or the like, so the populated parts of the ship aren't all that big. I think most Death Star cross-sections, for example, claim that most of the thing's volume is actually solid or void, not inhabitable space. You'd also probably need a large supply of automated systems and repair robots to keep things functioning. Still, you should probably consider how people actually get around inside the thing. A three-mile-long ship means that you need to walk at least three miles to get to the other side. (One thing I really appreciate about Star Wars's Malevolence was that it has an internal train system to move stuff around.)

I'll never forget a bar brag story I heard once. A crew of an oil tanker was sitting in a bar relaxing and a group of Navy servicemen walked in. After a few rounds, the sailors started talking about their ships and it turned out the Navy boys were off an aircraft carrier Boasting about how large the ship was and how it was a monster at 66,000 tons and took thousands of sailors to run The tankermen laughed at this because their ship dwarfed the carrier at something like 100,000 tons unlaiden, but only had a crew of 26 Edit: For y'all who are missing the joke here. They are comparing pp sizes, and while the aircraft carrier has a much different role, it's still sailors talking smack and the mid size tanker easily dwarfs the carrier, and could give it a piggyback ride. In most day to day operation, that aircraft carrier has to yield to the tanker because "might makes right" by navigation convention (smaller boat is more manuverable than the bigger one, and it's _way_ bigger and could run them down)

In Star Wars the point of the insanely massive ships was to scare the population into submission. When a ship is so large it can be seen from orbit the population in the shadow of that ship are going to live in fear. Many of us believe that the downfall of the Empire in Star Wars was due largely to the fact that they misallocated resources to these mega projects that were vulnerable to attack even from a single-seat star fighter.

One of the more notorious cases of the density issue was in the Honor Harrington novel series. David Weber had originally given the dimensions and tonnage of, IIRC, a dreadnought class warship, and someone actually did the math and it turned out the overall density of the ship was roughly equivalent to that of a cloud of smoke. He ended up retconning the numbers to something much more reasonable.

To make a somewhat realistic starship you need to think about it like an engineer. You first think of what you want this ship to do, and then you design how big it will be. Most warships in our time are essentially weapon systems that have a ship build around them to bring the weapon system where it needs to be, as well as some space for the crew that you need to operate it squeezed in between. You don’t want a big ship. You build your ship as big as it has to be for the intended purpose, but not bigger.

In defense of the pillar of autumn, a large portion of the ship is devoted to its giant gun and structural supports.

In my view, superships exist for one reason and one reason alone, to hold claimed territory. Once the assault ships and massive fleet battles are over, you warp in the uss huge AF to now act as a mobile star base. This ship should act as the main supply base and fort for your occupying force, it launches strikes from a distance and maybe even acts as a carrier for smaller destroyers. Kind of like if the Enterprise had a pocket defiant with it.

“Star Wars has this strange one-upsmanship that seems so petty!” Star Wars Legends: _Laughs in Suncrusher_

I remember a little graphic EC_Henry put together that really shows the absurdity of this sort of thing. He had the entire crew of the Enterprise D stood up side-by-side on the hull in close formation and they basically amount to an inconsequential speck on the hull. If you found yourself on a random hallway inside the thing you'd think the whole ship was abandoned just based on how long you'd have to travel before you ran into another person. I think in his breakdown he said that if you divided the livable space on board the ship evenly between each crew member, they'd each be given roughly a square kilometer of space on the ship.

Most people: Heresy!

I think one way to excuse it away for yourself, is that we don't know how big all the machinery is. If the ship is 3 times bigger, but holds the same crew, let's just say the extra space is needed for supplies/machinery. And, if the crew seems too small for the size, then consider that there is a lot more automation on that ship somehow (as universes allow), for example AI crew, repairbots, etc.

Wasn't the UNSC _Infinity_ originally a colony/ark ship? That would be pretty much why it's so huge: much like the _Supremacy_, it was actually designed as a mobile base.

"If you do specify a mass for your creations make sure they're in the right ballpark." *Thinks about David Weber's Honorverse ships having the density of smoke, before he corrected the numbers in later editions*

You see, my opinion is there are two ways you can have absolutely giant ships. A. Massive interstellar empire capable of producing a ship like it en masse due to their technological prowess (Forerunner Ecumene). B. It is the most technologically advanced ship and the pinnacle of research at the time (UNSC Infinity). The Covenant, as a side note, is somewhere in between with the 29km long Sh'wada-pattern supercarrier. It takes an immense amount of effort to build a thing, and while there’s definitely more than what we saw in the games, they’re not very common. We only know of two in fact, the Long Night of Solace, which was destroyed during the Fall of Reach, and the Hammer of Faith, which was never completed due to it being destroyed by Blue Team during Operation: SILENT STORM during the Attack on Zhoist.

As soon as the topic for this video came up I thought of Spaceball 1. Spacedock does not disappoint. "Why were you running?" "This ship is too big! If I'd walked, the movie would be over!"

To be fair, the Infinity was also supposed to be a mobile city, as it was originally a mobile ark in case of extinction.

40K's occasional low crew sizes makes more sense when you realize Servitors don't count as 'crew'. Other time there's whole communities of thousands upon thousands living in sections of a ship that barely interact with the rest of it's crew, living for generations just maintaining some part of the vessel as a cultural tradition, mostly otherwise unaware of their place in the galaxy.

"If you make something bigger, you make it heavier, which means you need more propellant.." The fact that this came right after the square cube law is funny. Bigger ships can carry a higher proportion of fuel, and can therefore achieve much better range and/or top speeds.

It is worth noting, if you are intending to have a ship that can operate independently for long time periods, you would go big probably, resources aren't an issue generally once you have asteroid mininig at a high level and if you don't need to pull out of a gravity well, larger let's you have full ecosystems for oxygen, water and food supply, good radiation protection just from the hull as well as space for solar panels and radiators. Not to mention any armaments, docking spaces for smaller craft, mining equipment etc. Of course, in support range or with a fleet this logic does fall down somewhat

I always liked that the Tauri ships in Stargate were more realistically sized. The BC303/304 ships had a fairly rational size for what they were intended to do.

The thing about larger ships being easier to hit comes down to what space combat is like in the setting, I believe. If fighting takes place at hundreds or thousands of kilometers while all combattants are zipping around at double digit km/s, I imagine that whether a ship is 1 km or 5 long doesn't matter as much. Within half a second it will be in a completely different spot anyway.

This is why I like the 40k approach, a galactic empire not only builds big, but builds *lots* of ships.

The funniest part about most huge sci fi ships is that, with what we know about heat build up, they arent _big enough_ to support their crew and armament and not end up as glowing infrared slag hulks just from their inability to shed heat.

In some of these, the ships have purposes beyond simply combat. The UNSC Infinity was I tended to serve as a lifeboat for humanity in the case of Earth falling, allowing the species to escape, plus the primary design consideration for all their ships is where the mass drivers go, and the bigger it is, the more powerful it is. Battlestar Galactica was never intended to enter atmosphere, so it isn't bound by concerns about gravity or drag, and includes limited manufacturing capabilities, while Battlestar Pegasus has enough manufacturing capability to make whole new auxiliary craft. That's even why the ridiculous megaship in _The Last Jedi_ works, but only if you've read extra materials that state it can build Star Destroyers. But ships beyond a couple kilometers that are solely for combat seem a bit silly, and exist only for bigger-is-better logic.

Ships getting bigger isn't new. Modern destroyer and Cruisers are as long and as massive as early battleships.

To ba fair to Star Wars, it's canon that Imperial-Class Star Destroyers are logistical nightmares, and it required a military apparatus the size of the Galactic Empire to field such a ship. When the Empire fell, a huge number of them were mothballed because the infrastructure supporting them no longer existed. Only the most powerful warlords like Thrawn and Zsinj could keep using them, and even then they were usually operated in a reduced capacity (skeleton crews, limited fuel reserves, understrength fighter wings, etc).

Do note that larger ships can equip longer-ranged weapons and better sensors so that they can hit enemies before enemies hit them. They probably also have longer cruise ranges, since they have more room for crew compartments and supplies. They might also survive harsh environments (such as the atmosphere of stars) which will instantly annihilate smaller vessels.

Cargo ships bring smaller than warships is a very ww2 convention where break bulk cargo was the only kind of cargo and the only thing really bigger than a warship was a passanger liner.

I always liked how in the Universal Century of Gundam ships were closer in size to reality. Ships were generally unshielded and no larger than needed. The largest ships are specifically carriers.

You know, the other factor that scifi usually doesn't talk about is heat radiators. Which brings up the idea of big huge sections of these ships being essentially just dead metal and space used to drain thermal energy from the actually important bits of the craft.

One reason for large ships that I like is them being huge because the FTL technology requires a ton of hardware or the way that FTL works it's far more efficient to have one huge ship to make one trip then trying to make smaller vessels darting back and forward (Too much energy, takes too long, etc) Then think how huge ships would effect your setting.

Regarding armor, the square cube law means that scaling up ships requires less armor per unit of volume the bigger they get.

Crew sizes vary wildly with automation. A modern NATO frigate has much less personell but way more firepower than a similarly sized WWII light cruiser. In sci-fi settings, most systems can conceivable run automated, including maintenance which can be done with robots/droids etc.

I think the mass conveyor from 40k makes sense actually. Its working on the same idea as modern cargo ships. The settings FTL option is also probably a factor. Its kinda weird actually that 40k has better considered cargo ships than most other sci-fi settings.

I my setting, massive ships like these are used more as mobile space stations rather than actual capital ships. Intended for establishing an orbital launch platform rather than fighting in pitched battles. (And by "massive" I mean the size of standard Star Destroyers or Galactica, not the crazy huge stuff)

I always thought it was funny how Star Trek TNG always made a big deal about life support failing despite the fact that the huge volume and small crew should give them hours/days of breathable air.

This was Thrawn's entire argument against making things like the Death Star, or the Executor Class, and he brought it up deliberately to Palpatine, that they could do far, far more with hundreds of fleet groups made out of the same amount of materials from the Death Star, it was just that Palpatine had different plans that required them so whether or not you prefer the canon arguments for them, or the Legends ones with the Vong, they had their purpose, it just may have been better to make way more ships than a single, gigantic asset that was incredibly devastating to have destroyed.

I like the size of UNSC ships in Halo. They seem signifigantly more realisitic to what would be viable. The largest ship ever made by the UNSC was the Infinity, and its 5.6km long, with a crew of about 18k people. The most prolific ship was the Paris class frigate, coming in at a very nice 535 meters long with a crew of around 250 people.

I always found it interesting how giant battleships never actually did that much. They were so big and expensive that no one wanted to risk them being lost and so there were very few large battleship engagements.

I have a growing fondness for the smaller cargo ships, like Serenity, Millennium Falcon, Ebon Hawk, and that new ship from Star Wars Outlaws.

Really big spaceships make more sense if space travel takes longer. More room for supplies and regenerative systems of all sorts. If you can zip to any part of the galaxy in a week or less, they don't need so much storage and regenerative systems.

Something I always liked about Mass Effect is that their ships are a much more reasonable size compared to other franchises. The Reapers are the biggest vessels (being a maximum of 2 kilometers in length) and they're treated as incredibly dangerous still. The codex mentions that their energy cores break physics as they know it, allowing them to operate near infinitely; and they also mention that most of their power is diverted whenever they land just to support their own mass in gravity. They also show why they don't care about being bigger targets, because their shields are so tough that you'd need to outnumber them four-to-one with dreadnaughts to wear down the shield. Anything less they could indefinitely protect against.

I like the idea of a big ship having it's own industrial complex, the AI ships in Polety comes to mind as they have it as a self repair and re arming production. And the Mega class star destroyer sounds like a awesome "villain" plot for starwars if we say they eat asteroids and poop out warships.

8:31 Pegasus was bigger as you know in part because it had an onboard foundry for building fighters and was a much more advanced BS and newer too.

There is a logical sense that I apply even in my own writing: 1. It's not necessarily about quality ships but quantity. You can build a mess of medium-sized ships (200-300 meters long) instead of one large ship. 2. Warships are ineffective if they are too small. Diminishing returns for building something too small to be ineffective in combat. 3. Ships that are too big warrant more resources and the threat of losing them. Large ships can be easily destroyed by a singular nuclear warhead if it penetrates the hull. 4. You can have big ships if your crew (alien race) are also large to operate them.

Having seen a lot of your guys' videos on space combat and ships, I came to the conclusion that bigger war ships only really make realistic sense in a setting that has some sort of energy defence shields. Bigger ship = bigger reactors = more powerful shield = can absorb/deflect more damage.

There are a couple important things missing from this discussion (which admittedly are often glossed over in the source material, too)…Aircraft carriers do not need to carry reaction mass, which many space ships do, and take up a large percentage of their capacity. They also need to either carry an entire ecosystem with them (to supply food, air and water as they go along), or carry enormous stores with them and restock frequently, which is difficult as space ships will generally be MUCH farther from port than any aircraft carrier ever is.

The one thing that seems to be ignored with most large ships is they are never alone. A modern Aircraft carrier has several ships around it providing a ring of protection and rarely gets involved in battle directly. There are missile cruisers around it, supply ships that come and go, submarines, and mine sweepers.THe total coverage is up to 50 kilometres directly and with AWACS they can cover 10 - 200 km. So if anything has gotten in striking distance the taskforce commander and the supporting commanders have made grave mistakes.

In my setting, massive ships are basically a requirement. The most powerful energy source in the modern era is the psychoblitz reactor, which basically means "stick a black hole in a containment chamber, use psionics to extract energy from it". Problem is, these black holes are still subject to hawking radiation, and if they're too small, they will evaporate almost instantly, which means psychoblitz reactors are not viable for small scale use. This effectively means the smallest a ship can be while still being practical is several kilometers in length and diameter.

I love enormous star dreadnoughts but they are far too common. A lot of franchises feel like the only reason their ships are so massive are because huge numbers are needed to feel big in Sci fi. In my own setting, most ships are surprisingly large for their crews because ftl is still long duration between stars and you need a lot of supplies, plus most ships exist to carry people or cargo. The hero ship is a refit cruiser and is kitted for exploration - it has a small enough crew of a few dozen but is still over 100m in length. This is because it needs supplies for long voyages and systems and options for any conceivable enigma they stumble across in a Big Scary Universe.

The “too big ship” and logistics I think work the opposite way. Modern ships have a minimum size for endurance. One the the failings of the US corvette sized (3000 tons) LCS was that it was too small to operate for more than a month at a time. Crossing either Atlantic or Pacific takes 1-2 weeks, so these ships had to be forward deployed. For comparison, 9000 ton DDGs routinely do 9 month deployments. As pointed out, a space ship is going to use a lot of its space for fuel and food.

The Expanse really shifts my perspective on things. As ships are vertical rather than horizontal, a 36 m long ship is still adequately sized, with several floors. I think a Donnager, state of the art battleship, is around 540 meters or so. And it is the largest capital ship in the Martian navy. It can actually fit escort ships within its internal drydocks. When designing custom ships I try to reference things like The Expanse, the Soujourn and Halo, and the scale is way off. Not sure what my point is, but can we have a whole series on designing new space ships?

Also try Star Wars KOTOR, where no warship outside of the comics is more than 1200 meters long. A Sith dreadnought is between 600-800 meters, and most Republic ships are barely over 100-500 meters.

The reason why the UNSC Infinity was so big was because it was meant to be a contingency in the event Earth fell and the war was lost hence why it was designed to be self-sustaining.

"Warhammer 40k" Well of course, that's the point of Warhammer, it's a parody

5:04 Dad's bringing in the groceries understand this principle well

The thing with large ships is there gets to be a point where you don’t need more people to take care of it

They're incredibly unrealistic even for their own universe's logic, yet they're way cooler than any reasonably logical ship will ever be.

Want to blow your mind? First, look up shipping container ship size compared to an aircraft carrier, and after that look up the "Blue Marline ship."

I agree that sometimes people just throw out numbers based on pure shock value/spectical or an endless game of oneupmanship, but otherwise I think it’s almost expected. Given the economy of a more developed and technologically advanced earth, multiplied by all of the developed planets in a sci fi state, plus all of the colonies and stations, you will have either massive ships, or tons of them. More likely both, like we have seen throughout history of capital ships and escorts: ships of varying size covering each others weaknesses.

4 main issues I have with this which can end up really effecting the sizes of ships. Most of which can basically be summarized by 'if this were true, then who would have build battleships.' First, armor is probably to be in an all or nothing scheme, where more vital parts of the ship would have more armor and the rest would barely be armored. If you can double the protections of the guns/command/communications/magazine/sensors etc at the cost of less armor in stuff life crew quarters, then the ship is already surviving longer in combat. Second, sci-fi ships would have a much greater degree of automation, you can just have a swarm of roombas instead of having a crew whose primary job is to keep the floors clean. Using Star Trek replicators, as an example, means you can remove anyone who works in the galley. Third, for at least some of the settings, the size of ships is pretty much standardized, and naval arms races between factions will gradually increase the size of ships as everyone wants to have the new class of ships be better than the old one and the enemies' counter to it. Over the last 100 years, the displacement of a US destroyer has gone up around 9 times, despite the newer ones being basically unarmored compared to the old ones. Assuming this trend continues, then in ~60 years, destroyers will have the displacement of an Iowa Class battleship. Fourth, and something very few tv/film series ever take into account is how target acquisition works in space. The distance you can hit a target is significantly higher than any series which lets you clearly identify two ships shooting at each other in the same shot. not to mention how speed vs armor has pretty much always been the biggest tradeoff and most of said film/tv does not have practical evasion for capital ships. This gets even more confusing when you realize that bigger ship means bigger engine means you can put more armor for the same speed.

When I watched Space Battleship Yamato back in the 70's, they made her seem huge on the inside, being able to hold dozens of fighters and support craft. In SBY 2199, they scale her back to the original Yamato's size, as they stick only a few fighters and support craft wherever they can find room.

In terms of realism I actually think bigger is exactly how it's going to be done in the earlier stages. These will be multigenerational vehicles so the size is to accommodate room for future growth and lots and lots of fuel and supplies.

There's a reason why my current shipbuilding project is keeping most warships at something like 25-50% of their "wet navy" versions. There's only so much you CAN do with that mass and while there are larger ships (freighters and colony transports), most warships are in the 250m-2km range. And even the largest warships are literally the hub of a fleet and not independent combatants on their own. Still, I do have a fond love of the ships of "Gunbuster," which are HUGE (the biggest is 50KM).

Why shouldn't sci-fi ships be less crew dense than their US navy counterparts? Have you seen a submarine? Consider crew comfort if you have the luxury of making a bigger ship. That and you should consider even if it was supposed to scale, it would do more to the surface area than its size.

Dune's Cargotrailers really deserved more attention as they are designed to exploit economy of scale to an absurd proportion. Navigators are rare in the Dune universe, they need precious Melange to operate the ships, so the more cargo you can fit into the single vessel, the better. All space travel is basically a "mass transit" in the Dune universe. They also fold space, so they do not need to care about things like inertia. Their tubular design is very effective and structurally sound.

There are actually a lot of reasons why space ships could be gigantic: 1. Economics 1. A warp drive might be expensive, but upscaling a warpdrive is not. Thus economics dictate that the more mass per warp drive, the better. (Also a great justification for having all warships carry potentially world-ending weaponry). 2. Economics 2. In low-tech settings transfer windows are of crucial importance for any interplanetary civilization. For example a Jupiter->Earth transfer window comes once every 13 months or so, and since Jupiter should be the focal point of every hydrogen-based economy they best make sure that as much cargo as possible leaves Jupiter during said transfer window, and the bigger the ship the less hull per cargo space. 3. Demographics. If you have some sort of nomadic society, they need somewhere to house their massive population base. Bigger ships means more space for people.

In defense of the Infinity, it was a colony ship first that was retrofitted for war and it has its own small fleet of warships it carries around. Then you also have the fact that AI is one of the reasons why UNSC ships can seem to be so under staffed yet seem to be completely fine in terms of them being maintained. This technically makes it easier to have a crew that's more easily supplied and feed for longer periods of time before needing resupply.

Try Mobile Suit Gundam UC timeline. Most warships are between 100-400 meters long, the only Star Destroyer-sized ship is a fuel tanker, and their idea of a large warship is 600-800 meters, less than a kilometer long.

I actually think a lot of sci-fi is UNDERSIZED for what they're trying to accomplish and the crew numbers quoted, for one main reason: Air is worth more than space, and " mostly empty" rooms with the same goods as well packed stores really dont add that much mass overall. Air compresses very well, so we all just sorta handwave "tanks in the wall" but to actually get not stale poor quality air you need space and exchanges of air between them. An emergency system may be able to dump 30 atmospheres into a room by the time its sealed. But you wont want to LIVE there. Air needs room to "breath" almost as much as people do. Empty space is a VERY cheap solution to that problem. Weight of materials is actually a pretty inconsequential calculation to cost to manufacturing on an industrial scale. A big box twice the size of another box isnt twice as expensive, because theres a certain minimum amount of effort to get everything to make the box to the right place. Bigger is usually cheaper per inch or meter. For a minimum increase in weight, say 10%, you can probably get a 25% or greater "size" with all else being equal. Since we're mostly talking future space magic areas, that cost benefit seems cheap for the one thing you CAN'T trade for, air. You can convert water into it sure, but air compresses better so why bother? Most water is a closed system anyway, so better to overstock air and recycle water.

Always keep in mind that size does not equate to destructive power. A PT boat can crank more damage than an oil tanker 95% of the time and the tanker's main attack would be a one shot deal that you could see coming from miles away. Literally.

For our sci-fi setting (Voidskipper), there's actually several very good reasons for the ships being so massive by most setting's standards: - Automation out the wazoo and ubiquitous brain uploading makes the crewing requirements vastly more manageable. - When a population of a trillion is considered an irrelevant backwater, and doing maintenance teardowns of entire stars is a common public works project, you can afford such huge ships. In huge numbers, too. - Warp drives capable of superluminal travel simply can't be miniaturized below a few kilometers, and neither can the required power plants. And you need to go significantly BIGGER than that before you can get a remotely practical payload fraction.

The real problem isn't the size of the ship, it's the size of the ship and what they're using it for. There is a maximum size for a warship beyond which just building a fleet would be better than building a huge ship. If it's larger than that limit, it needs additional uses, such as being an armed colony ship or habitat.

I thought the Infinity made sense for its size. Most of the space in the vessel was taken up but the MAC guns, armor, engines, and other ships it carried inside it. It also carried marines that wernt part of the crew and their equipment so I don't see room for the ship to have a huge crew because u have the bridge crew, engineering crew and weapons crews but security is taken care of by the marines so maybe they might have some science people also on board but I dont think they had much extra space.

It is nice though when there does exist a big ship that actually has a reason to be there, especially if it's the only one of its kind. Something like The Ark from Transformers: Fall of Cybertron comes to mind.

When your space ship is so big its own gravity causes it to be a ball.

Its the main reason I love homeworld. The assault frigate is the size of A corvette A battle cruiser is smaller than A star destroyer The pride of hiigara is smaller than the Super star destroyer

In defence of the Infinity, it does have its own means for food growth. It was built as an ark for humanity if the covenant ever glassed earth. Halo Warfleet is great for more info on it.

My biggest pet peeve in the scale thing is that the difference between cruisers and battleships or any other type is that the size is increased three fold or more when a huge difference in real life is maybe a 20-60 meter difference in length and a 5-10 meter difference in width

Real-life warships are insanely crowded. Some even utilize hot-bunking (one bed for two men, one man works, one man sleeps) to save space. If everyone was afforded actual personal living space aboard, you could easily inflate even a regular modern ship to 1-1.5km long without expanding its crew complement. And yes, what a concept, the Empire providing individual sleeping quarters for every stormtrooper, but then again why not. Working in space, even in fantasy space, is a lot harder than working at sea - you can't go out on the deck to breathe some fresh air and smoke a butt. It would be like being on a submarine that can NEVER SURFACE. Even the sturdiest men would start to waver and break after a while if not given space to unwind, especially on the Star Destroyers that are meant to be deployed for months and years at a time. The Empire might be evil, but it ain't stupid. Well, mostly.

"You could try to make these weapons smaller, but to maintain the same effectiveness they need to use more energy for unit volume, and that's a recipe for melting." That may apply in the heat of battle, but in the long term, what matters is energy per surface area. Especially because dissipating waste heat in space is pretty difficult.

As shown in S4 of BSG though, there is an entire negative space (empty space) between the outer hull and the inner hull, plus the additional very thick framework that made up the ship's integral structure, when excluding all that, the actual area where people moved around is considerably smaller than what the ship makes it look like. And as for the UNSC Infinity, also explained in canon, as well, the ship was comissioned just after humanity got one-halved population-wise, so much less personel was around to crew a single ship, as well as the ship not needing as much personel as it could hold.

I'm tired of people thinking 1km is 'big' in terms of space craft.

at least when David Weber's honorverse books went into bigger ships much of that size went into missile storage, in a setting where missiles quickly became the most important armament that a warship could have

Just skip to 2:00

There was this scifi parody, where they put engines on planets and flew around with them, because it was cheaper that way...

One example of a big ship whose size is absolutely justified is the Nauvoo from The Expanse. In any harder sci-fi setting without artificial gravity, if you want full 1g gravity, you're going to need a pretty sizeable ring or drum. If the idea is that there's something like a self-contained ecosystem inside, I think again you're justified in having it be a pretty sizeable drum, ie an O'Neill cylinder.

I am not tired of big sci-fi ships. Love it.

That poor Evergreen ship can never catch a break.

Not even a little bit tired of absurdly large ships. Love giant ships.

Honestly, considering the galaxy portrayed in 40K, I think the Universe Class cargo carrier is actually legitimate. Imagine how much you'll need to haul to supply an entire WORLD with food/water/air(sometimes) and a wide variety of everything from raw materials to advanced tech. Now add that every trip is risky, so you want to make as few as possible.

6:39 The square-cube law still benefits larger ships, as even though the armour is not simply a coating, it can be treated as such relative to the total cross-sectional area of the ship, which would reasonably be one or two orders of magnitude larger than the thickness of the armour (as an example, the beam, which is the widest point on a ship, of the _Yamato_ was 127 feet, while the armour on its sides was 16 inches). Another advantage of increasing size is that not all systems need duplicated if you ship becomes twice as large, so you now have more room for even more fuel or armour. The downside of scaling up is that while your fuel is going to increase volumetrically, your thrust is going to be bottlenecked by the surface area of your exhaust nozzle (assuming your big ship doesn't have a more efficient nozzle than your small one). So you'll have more dV on a big ship than a small one, but worse acceleration. you could of course, increase the size of the thrusters, but this will also increase the size of the silhouette presented to the enemy. Just based on on some loose estimates, a good size for a spinal-mounted railgun or coilgun that shoots telephone-pole sized tungsten projectiles is about 3,200 feet long. Beyond that, I dont think you would get much more value for getting bigger, and it could still be destroyed by an average nuclear warhead. To shrug off nuclear bombs, I think you'd need a ship the size of Britain or Oklahoma.