This week’s post will be a bit shorter, as the holidays are now upon us and the year is winding down (but don’t worry – I have a humdinger of a series planned for January – no, not that one; one you did not expect). This week is going to serve as a bit of an addendum to Where Does My Main Battery Go and a bit more silly sci-fi fun to round out the year. Specifically, I want to expand a bit on this statement:
Looking across naval design over the centuries from oars to sails to nuclear reactors, one of the few constants is that the overall shape and profile of the ships are dictated by propulsion and armament (with crew facilities essentially jammed in ‘wherever they fit’).
I wanted to expand on this idea and trace it historically.
What I often see in sci-fi settings are space warships that look like this:
Or even the venerable Imperial Star Destroyer (in this case, an Imperial I, because yes, I am that kind of nerd – you can tell from the communications tower):
What strikes me as off about these designs are their silhouettes – or rather, what they imply, which is that they have been designed around a shape rather than around a function. For the Star Destroyer, at least, I can see parts of the design that have been forced to make way for the main reactor, which bulges out of the bottom of the ship (but my heavens, the decision was made to deform the primary armor around the reactor, rather than simply designing the ship from the ground-up to put such an important thing entirely internal to the spaceframe?). But for what is essentially a gunship, what is so striking about the Star Destroyer is how muted the main battery is to the overall design – I suspect most movie-goers don’t even notice the turrets set on either side of the central island (which is also, as an aside, a terrible spot for them).
Instead, the main armament – and even, to a degree, even the propulsion – appears to be an afterthought. Some series do this more than others – Star Trek ships generally have very prominent engines (in those classic nacelles), but with such understated main weapons – even on the more militarily focused Constitution and Sovereign classes – so much so that the SFX teams routinely forgot what is where and had the wrong weapon shoot out of the wrong place (Kirk, in particular, seems fond in the original series of firing phasers out of his torpedo bays).
(I don’t want to get too out of the way making fun of Sci-fi ship designs, but can I just note that the basic layout of Federation starships – with engines connected to the main ship by long, fragile pylons, makes no sense. I mean, I understand from a production standpoint that originally the idea was that every ship would have two warp nacelles and they’d always have to have line-of-sight on each other to work (thus the moving nacelles on Voyager and Ferengi ships), but they seem eventually to have ditched that in later designs, which then makes what is supposed to be centuries of Federation ship design look really, really foolish if that line-of-sight thing wasn’t strictly necessary.)
What almost all of these ships seem to have in common is that they look like actually began with the shape of the ship and then back-filled how the key components of the ship might fit in with that shape. And that’s probably because that’s exactly how they were made – with artists and modelers working up from a basic idea of the overall shape and visual style of the ship and adding details. Often – as for instance with designers discussing Star Wars starfighters here (note that they discuss the new movie in the last few minutes) – they began by adopting shapes from existing machines.
The problem with this is that you get a ship where the primary purpose of the craft is literally an afterthought in its design – a few tiny ‘guns’ glued on to the side of the model after it is by and large done. And so what you don’t see – compared to any kind of historical warship – are the ways that the demands of the two most dominant design features, propulsion and armament define the shape and silhouette of a design. Indeed, in some ships, the design seems to literally contort around these features – as well it should, as they are the reason for the ship!
Early Purpose Built Warships
To see what I mean, lets talk about the design of naval warships. Now, in a way, the design of historical warships is, if anything more restrictive than the design of most space warships, which tend (in their respective fictions) to be built in space and never operate in atmosphere. Ships that ply the seas rather than the stars are constrained by the shapes they must have to sail effectively; starships have no such limitations.
I’ll cut to the chase: the silhouettes of historical warships are always dominated by two key factors: propulsion and armament. In nearly all cases, everything not directly linked to one of those two facets of performance is relegated to a secondary status (we should make exception, especially in the modern era for armor, but modern warship armor has more often had to conform to a shape dictated by the other two factors, rather than the other way around – that said, the impact of armor on weight was a huge influence in warship design, and a considerable, but more subtle and harder to spot – but very important – influence on warship shape).
This makes a certain degree of sense: the primary role of any purpose-built warship (aside: I’m going to avoid multi-purpose craft – ships that can serve both military and civilian roles – here, in both my sci-fi and real world examples) is to deliver a primary armament of some sort to a battlespace. The subordination of every other function of the ship to these main purposes plays itself out visually in the design. Let’s start with an old example: possibly the oldest purpose-built warship in the world, the Mediterranean trireme:
What I’m going to do with each of these images is put red marks around the primary armament of the ship in question and blue marks around the propulsion systems. In the event, the trireme is an awkward first example: the oars serve both as part of the propulsion, but also part of the armament, as the trireme’s main weapon was speed. While later Mediterranean oared warships may have been more focused on boarding (this is a hotly contested topic, I recommend W. Murray, Age of the Titans (2012) to get a sense of the debate and the design considerations it spawned), the trireme was definitely a ramming oriented ship. The perfect engagement was one where it got in, got the hit, and then backwatered back away again.
Consequently, triremes were built for speed, because speed was offensive power. Everything was sacrificed for this: there is functionally no cargo room, literally no crew quarters (the rowers slept on their benches) and the ship’s structure is built light and thin (with costs to both survivability and seaworthiness). Occasionally a sci-fi show will joke that a given ship is “little more than guns with an engine strapped on” but the trireme is almost literally this thing – little more than a ram with a (human powered) engine installed in the back.
Centuries of evolution in the design did not change the basic balance of speed and armament:
Moving into the age of sail, we can see a similar dominance in ships of the line:
Now, the ships of the line are a bit of an odd case, because they descend from, and thus share design characteristics with, the multi-purpose sailing ships of the 16th and 17th centuries. Nevertheless, the design demands of being a specialist warship have taken their toll: the demand for more guns meant stacking additional gun-decks vertically, which in turn gives the ship a deep draft (which you cannot see, because it’s below the waterline; and yes, yes, this is a British ship, so I suppose it has a deep draught). That in turn has demanded a broader beam (that is, the ship is wider) to maintain a stable platform – Victory, with three decks of guns (plus lighter guns on the quarterdeck) is nearly 16m wide, while a classic 74-gun third-rate ship of the line might be only 14m wide, and a single-gun-deck ship like a light frigate might need only to be 10-12m wide.
Alright, I hear you say, but what about a more modern ship? Something with an engine? One of the (more or less) constants of pre-dreadnought and dreadnought design was that, in terms of displacement (essentially weight), around two-third of any given battleship consisted of the main propulsion, the primary armaments, and the armor. Everything else – everything else: crew quarters, crew amenities (food, post, hygiene, recreation, social spaces), command spaces, storage spaces, damage control equipment, machining tools for repairs, all of it – had to be squeezed into the remaining third or so.
Meanwhile, the relatively inflexible demands of the shape of the main battery and primary propulsion (along with the demand for elevated command spaces to allow for effective navigation and spotting) mean that all of those other things had to be crammed into whatever space the ship’s hull made available. As an aside: this design philosophy is abundantly clear if you’ve ever been on a museum ship that lets you get around even a little bit – bunk spaces and mess halls and the like are crammed into whatever space is available, sometimes contorted around other, more important ship functions. For instance, the world’s sole surviving pre-dreadnought, IJN Mikasa:
Now, you may say – “wait, but you’ve designated the secondary guns as part of the main armament” – but remember, this is a pre-dreadnought, so the secondaries are still conceptually part of the main armament, which is why they’re allowed to dictate so much of the ships central mass, rather than being confined to casemates or upper-works wherever they will fit (a more common pattern in later dreadnoughts, until WWII when the placement of secondaries, now anti-air batteries, begin to matter a lot again) – instead, the housing for the casemates of the secondary battery is a core part of the design and takes up a lot of the space above the waterline.
The propulsion system of a ship like this dominates the space of the ship’s lower decks. On Mikasa, directly beneath the smoke-stacks were 25 coal-fueled boilers, which fed power to a pair of triple-expansion engines (a compound steam engine which passes the steam through multiple cylinders to extract more power) set aft of the boilers, which in turn drive the shaft out to the propellers. The space the entire assembly demands is actually visible in the placement of the stacks – no doubt naval designers would have loved to place the smoke-stacks somewhere, anywhere where they wouldn’t frequently cloud the aft spotting tower with smoke, but the demands of powerful engines capable of moving such a heavy ship at respectable speeds forced compromise.
I think modern warships – by modern here, I really mean post-1880 or so – conceal some of the degree to which propulsion and main armament dominate the ship’s design (and thus its appearance) because so much is hidden beneath the decks. Note, for instance that the big-gun turrets are not the only part of that gun system – the entire gun assembly is actually five decks tall, plus the turret, beginning with magazines and ammunition storage at the bottom, and a lift for shells to be brought up to the guns. The motor that turns the turret is roughly at the waterline (on the platform deck) and the systems to elevate and train the guns are themselves nearly two decks tall. That assembly is protected – above and below the main deck by an armored shell called a barbette. A large part of the reason this entire setup is stacked vertically is so that the magazines – which take up quite a bit of space – can be placed as low in the hull as possible, since a hit to a magazine would almost certainly doom the ship. In short, the barrel of the gun and the turret that you see poking out of the top are just the tip of the iceberg of the total gun assembly.
And remember, this is a pre-dreadnought, oriented around a mixed battery of guns. What about a modern ‘super-dreadnought’ all-big gun battleship? Now, I’m sure you’re all expecting Yamato and Musashi‘s massive 18.1in guns, but I don’t have a good internal layout plan for the Yamato, so I’m going to go with an USN Iowa-Class ship, the USS Missouri (BB-63), both because I can find a full deck plan, but it’s also a design I’m more familiar with. Same deal as before:
The turret assembly for each of the (technically-not-triple, they can elevate independently) triple-16in turrets is even larger than Mikasa and runs all the way to the keel and fills nearly all of the horizontal space on every deck with the equipment for raising shells, elevating the guns, turning the turrets, magazines and so on. You can get a pretty good sense of what all of the stations in the turret are doing from this 1955 training video on the operation of the guns.
I want to contrast that with the scale of a Star Destroyer’s main armament – you will need to excuse the poor picture, I took it from my copy of Star Wars: Incredible Cross-Sections (I told you, I am that kind of nerd – I’ve had this book, along with the Essential Guides, since I was in high school, much of it even back before the Dark Times, before the Prequels), the book is quite large and scanner-unfriendly, so I had to use a camera:
By my count, the entire assembly – fire control, power cells, the turret itself, everything but the reactor powering the damn thing – comprises about 8 decks. To give a sense of the comparative size of these two ‘battleships’ – the Mikasa is 131.7m long and has a beam of 23.2m; a Star Destroyer is supposed to be 1,600m, and up to 600m wide. It is, conservatively, something like two thousand times larger than Mikasa (perhaps a thousand times the size of Missouri) in terms of total volume, yet the gun main gun assembly looks to be only a bit larger – and it includes fire control (which was not housed inside the turrets on historical battleships because that is a very silly place for it) – and it only has eight main turrets. The total volume – and one assumes mass – of the Star Destroyer devoted to its armaments – even if the main reactor is included – is shocking small.
It really makes me wonder what all of those other decks are for on a Star Destroyer. Oh, sure, you have the hanger spaces, but these are all in the thin end of the wedge and don’t even seem to fill that – what on earth is taking up all of the space in the massive island in the center-aft of the thing? Looking at various cross-sections and technical drawings, the answer appears to be ‘nothing.’
(As an aside before it comes up: ‘what about aircraft carriers?’ Well, the main armament of an aircraft carrier is its air-wing, which (in its full operation) takes up the entire flight deck, plus the entire hanger deck, both of which in modern carriers run the full length of the ship, plus armory spaces further down and repair and machinery. If anything, an aircraft carrier is more contorted by its main armament than any other modern type of warship.)
After the last post on sci-fi ship design, a number of folks asked me if there were any designs that struck me as having felt a bit more on-target. And there are some – a common design, particularly in video-games, are ships built around a single large spinal-mount railgun (e.g. Mass Effect, Halo), resulting in a design with a main reactor in the middle, plugged into an engine assembly behind it, a gun assembly in front of it, and the rest of the ship essentially wrapped around that core in whatever shape will fit. I also think that – though I am only now making my way through the series – a lot of the ships of The Expanse strike a good balance, for instance the Donnager-class:
The main armament is on the bow in two massive turrets and one assumes that the power, ammunition and battery stems for those huge railguns dominate that mid-ship-section, while the massive engine (and presumably reactor) dominate the ship’s aft (although it also has a lot of big internal empty storage space which I find a little unlikely for a ship that is still essentially a gun-delivery-system. Science-fiction loves big multi-multi-purpose ships with marines and fighters and guns and mid-sized craft, but in practice it is hard to see why those functions wouldn’t be split up between specialist craft (so that you are only lugging the capabilities you need, all the more important when fuel and available delta-v matter).
And that will be the last scheduled Collections post for 2019. There won’t be a normal Friday post next week because of the holidays (I will be taking some much needed rest, and by ‘rest’ I mean I will be attempting to catch up on my research). The week after that will also be an ‘off’ week (the first week of January plays host to both the largest professional conference for historians and the largest professional conference for classicists and archaeologists. Obnoxiously, always on the same days and never in the same place.) I may have a few one-offs here or there, but the regular posting schedule will resume on January 10th.
New things to come with the New Year!
68 thoughts on “Collections: Starships in Silhouette”
It doesn’t help that depictions of Star Wars capital ship armaments vary wildly between sources. Wookiepedia lists so many armaments for the Imperial Star Destroyer that it’s hard to tell if it has a proper main battery armament as we’d recognize it. Not to mention, while we don’t explicitly see it used as such in the films, the ISD (on top of its battleship and carrier roles) apparently also serves as a troop carrier/assault ship. That might account for some of that inexplicable “unused” space — it’s Stormtrooper barracks, multi-environment training rooms, and storage for all those AT-ATs, landing craft, prefab bases, and other stuff it’s allegedly ferrying around all the time. Which gives you an explanation for all that space, but makes the jack-of-all/master-of-none problem even worse.
Judging from its cutaways, the Venator Star Destroyer from Revenge of the Sith might be a better example of a ship built around its armament and engines — it’s overwhelmingly a carrier, and much of its bow and keel are built around its hangars and flight deck (that we never see in the films). Although it still suffers from the poor main battery placement of the ISD.
A possible post-facto explanation for the seemingly miniscule armaments might be that the real main armament of a ship armed with energy weapons is actually its main reactor, and the ship has just enough energy weapons/emitters to make full use of that power, such that adding more guns wouldn’t actually allow you to put more energy on target. But that suggests you could dispense with the fighter and troop facilities to build a smaller warship with just as much antiship punch as an ISD, which ought to be the main backbone of the Imperial Navy. Unless, in the post-Clone Wars environment where the Empire no longer faces the Separatist naval threat, ferrying around Stormtroopers and their kit to suppress planetary uprisings is actually the ISD’s primary role, and its antiship role is practically an afterthought by comparison…
We do get a decent shot of a Venator flight deck halfway through this scene.
I’m with you on the post-facto reactor argument for Star Wars, and would agree that the Empire is primarily operating a force designed for counterinsurgency and police action rather than conventional fleet combat. An example of a stripped down pure warship might be the Separtist Recusant Class Light Destroyer from Episode III, which removes all the room for crew/troops and is purely optimized for combat.
>Unless, in the post-Clone Wars environment where the Empire no longer faces the Separatist naval threat, ferrying around Stormtroopers and their kit to suppress planetary uprisings is actually the ISD’s primary role, and its antiship role is practically an afterthought by comparison…
I know little about Star Wars, but I think it’s sort-of possible. I *heard* that in our times the whole idea of aircraft carriers is about pummeling poorly equipped states. Countries you don’t have a significant advantage over are supposedly able to effectively counter aircraft carriers, making them a poor investment. That would mean aircraft carriers primarily work against countries which can’t *afford* to counter them.
I don’t mean this as a criticism of aircraft carriers specifically. Relative power of armor and weapons changed significantly across ages. Perhaps in the far, far future are no longer a bully’s weapon. What I mean is that you don’t have to be very efficient against much weaker enemies.
Aircraft carriers are really useful and convenient for plinking trucks in Libya, but that mission could also be performed by a much cheaper platform. The reason why we pay so much for CVNs is their utility in high-end peer state wars, whether that was the GIUK gap in the Cold War, or the Chinese A2AD zone today. Substantial developments have been made in anti-carrier hardware in the last few years, but the crux of USN planning against China still revolves around how to bring the carrier group into the fight.
The Empire/Republic always had naval dominance, I suspect, given they only have enough ground forces to invade Russia, then lose. The Star Destroyers primary role seems orbital bombardment & supply- you need both at the same time, so combining them isn’t an issue, and the Tie Fighters are well equipped for a space-craft designed for orbit-surface attack (inexpensive and maneuverable is probably the way to go when you’re going to be engaging in atmosperic fights- an X-wing is far costlier to lose, given it’s additional shields and hyper-drive, and is only slightly safer from bad conditions, given how Luke, the rebel’s ace pilot, once crashed his into a swamp due to fog).
So the Star Destroyer stays in orbit and blows up any significant pockets of resistance (i.e. whole cities/ small countries) with it’s absurdly powerful turbo-lasers (it only takes a star destroyer 1 day to glass a full planet, so while it doesn’t have numerous guns, each is perhaps overly ‘large’. It is a laser, so this isn’t reflected in physical size), and also supplies ground troops that move in and establish control of local government/clear areas of vital resources.
Note the first time we see an ISD that’s apparently performing it’s standard role, it’s doing a customs blockade and supporting the occupying force on Tattoine.
At least, Han is a bit surprised to be getting personal attention from the 2 ships but not surprised that they’re in orbit and trying to blockade a small freighter, which tells me that’s a standard function. Likewise the stormtrooper presence in Mos Eisley might be heavier than usual but the citizens don’t seem to find it unexpected.
I would go further and argue (while I mostly agree with the substance of the post) that the Star Destroyer is not primarily a warship. As in it’s primary purpose is not to fight and defeat enemy warships of similar size and threat, because in the period they were designed and used (19 BBY onwards) there were no true spaceborne military threats to the Empire (that it knew of).
The design and construction of the ISD comes as the Galactic Empire seeks to take and hold political power over old Republic and Separatist (whose droids have been shut down) systems and suppress insurgency (a real but also artificially amplified threat). Richly flavoured with the Empire’s brand of fascism
The ISD and VSD both aim to be able to do almost all sorts of power projection. The idea being that whatever the problem, the Empire can dispatch an ISD to deal with it. Insurgency, piracy, medical relief mission or simple intimidation, the ISD is a unit of military power that can do it all. The fact that I imagine it would be fantastically wasteful to design and supply something that *could* do all these things but rarely needs to do *any* of them probably doesn’t matter to the Emperor or the people in charge of the navy*. In the words of Zapp Brannigan “lets show these freaks what a bloated runaway military budget can do…”
They are carriers (with the ISD, iirc, carrying and deploying 6 squadrons of TIEs with 4 full squadrons of reserves plus pilots, engineering crews and repair/rearmament facilities).
They are troop transports come assault carriers with men, equipment and transport to land and support a small army. Like a lot of modern naval carriers and assault ships I think we can safely assume they get used as humanitarian (or rather the Imperial equivalent of “we need the stuff these people make so we probably should save some from the deadly space virus”).
They are warships with enough armament for use against planetary and spaceborne targets the Emprie thought they might face (the Rebel Alliance’s premier capital ships like the Calamari cruisers were at least in the old canon beautiful cruise ships the Mon Cals very reluctantly retrofitted into warships).
These ships are also long range power projection platforms. They are big, imposing and frightening to see appear over your planet/city/home (I’m thinking of the one in Rogue One descending into the upper atmosphere). They also, we can surmise, have a very long operational range. Before Disney Thrawn canonically spent years at a time in command of a single Star Destroyer exploring the unknown regions, indicating that while they probably didn’t usually do so the ISDs almost certainly have the capability to go without full resupply for years at a time.
Basically I think that empty space is probably just full of MREs, clothes and spare stormtrooper armour…
*The EU books, in particular the X-Wing series which I’m drawing a lot on here, portray commanding a Star Destroyer, especially an ISD I or II as *the* plum assignment. Every navy officer wants to command one and few-to-none of them have any interest in pointing out how wasteful the way they do things presumably is compared to building and using more of the specialised designs that did exist.
I understand that movie and TV show starships operate under the guiding principle of “the rule of cool” but it is refreshing to see someone address just how poorly designed these ships are.
I also get a laugh out of how wonderfully spacious every room in a starship is, including warships. Living quarters, for example, often seemed bigger than my apartment. On a real warship it is more a matter of how many people can we stack in as small a space as possible?
One thing I’ll note about Star Trek: other than the Defiant class, the Federation does not have warships. And when most of your crew scientists and their families (like the Galaxy class), you want to make sure you’re not pissing them off by giving them tiny quarters.
I suspect I’ll come back to this later at some point, but I’ve always found the ‘it’s not a military’ argument unsatisfying. Honestly, it strikes me as empty preening by the early-season TNG crew, and isn’t reflected in the rest of the fiction – Kirk’s Enterprise is explicitly a ‘heavy cruiser’ which is a very real military ship class, while Starfleet is very much a military in DS9, VOY and ENT. Sure, it also does cartography, engineering and science. So do real-world navies – so did the age-of-sail navies it is patterned on.
It’s so much that it isn’t military, as it’s… what should we call it… their “Science Marine”, doing double duties. Which considering what the Enterprises keep running into seems to be exactly what you need for these long-range missions – there are far too many things that would just kill a dedicated warship dead. Then, if they get into a bad war, they gear up to proper warships (although the more sensible solution would be to have those mothballed in advance).
Compare with how the Culture gears up to war footing in ‘Consider Phlebas’ by first running defence with their General Contact Units, then putting Rapid Offensive Units into production, and finally using fully weaponized General Systems Vehicles.
If they’re not a dedicated warship, it should be common for them to get their butt kicked by combat-optimized ships with experienced captains. How does the Enterprise fare against warships?
One line of thought is that they’re advanced enough that their flying kindergardens can hold their own against e.g. Romulan capital ships. Which I think is supported by TNG stuff.
Similarly Culture GCUs are “unarmed” but can arbitrarily re-arrange atoms from an adjacent solar system, so unless you’re advanced enough to block their effector fields or whatever…
Kind of like defeating a medieval knight with your laser pointer.
Actually, they are military, but Age-of-Sail military which is responsible not just for naval supremacy, but also colonial warfare, exploration, sciencing and so on.
“If they’re not a dedicated warship, it should be common for them to get their butt kicked by combat-optimized ships with experienced captains. How does the Enterprise fare against warships?”
It’s extremely heavily armoured in plot armour.
This might not be illogical if one takes into account that people in a space-based civilization are going to be spending a significant fraction of their LIFETIMES sealed inside these pressure vessels. Starships intended to house their crews for years without relief or shore leave might indeed have to be designed more like habitats than like missile silos or submarines.
So where do the weapons go on that flying codpiece from EVE Online ?
Games usually want to let players customize their ship weapons after the ship has already been built. I imagine most ships can’t be fully refitted, so this is unrealistic and you should instead replace the entire ship when you want different weapons. For most players it’s more fun to explore different weapon combinations with no major commitment.
Judging by EVE wiki, ships have very modular, highly vague weapon system with high, medium and low points, and there are two types of weapon slots: launcher and turret. When you’re this vague and flexible with your weapons, it’s hard to even imagine how you would build a ship around them. Honestly it looks like most of these games have liquid armaments, and you simply pour the machinery into some kind of a tank.
Being modular carries an overhead. Cargo containers are a lot of extra weight and space, but their main advantage is being able to quickly load and unload stuff. I would enjoy reading an article why designing ship weapons as plug-in modules is a bad idea.
Star Sector is only a bit more specific: Energy, Ballistic, Missile, Composite(?). According to their wiki, it’s common for various warships to be pre-dreadnought. They rarely can focus all their biggest weapons on the same target.
In Eve-Speak the correct term for that craft is “Golden Turkey” or “Golden Chicken” due to its uncanny resemblance to a frozen turkey.
I refer to it as “Gilded Poultry.”
That must be a new nickname – I actually flew the Damnation back when I played EVE (uh, ten years ago?) and it didn’t have a nickname that we used then; just the ‘damn’ and the ‘abso.’ But I know a ton has changed since then.
A most excellent look at an important issue, although I have a few extremely pedantic quibbles.
>One of the (more or less) constants of pre-dreadnought and dreadnought design was that, in terms of displacement (essentially weight), around two-third of any given battleship consisted of the main propulsion, the primary armaments, and the armor. Everything else – everything else: crew quarters, crew amenities (food, post, hygiene, recreation, social spaces), command spaces, storage spaces, damage control equipment, machining tools for repairs, all of it – had to be squeezed into the remaining third or so.
The big things that fill the remaining 40% or so (I’ve usually heard the rule as 60%) are fuel and structure. All of the stuff you list is pretty much a rounding error compared to those two. To grab the first set of figures I can find, the Queen Elizabeth class (~27,000 tons) comes in at 8,900 tons for the hull, 8,600 tons for armor, 4,550 tons of armament, 4,000 tons of machinery, 650 tons of general equipment, 100 tons of board margin and between 650 and 3000 tons of fuel depending on loading.
>technically-not-triple, they can elevate independently
The three-gun vs triple is a peculiarly American quirk of terminology, and calling them triples isn’t really wrong. The single slide appears to have only been used in battleships for the Nevadas and Pennsylvanias, although honorable mention goes to the 2-slide French quad turrets.
>which was not housed inside the turrets on historical battleships because that is a very silly place for it
Only sort of. There was backup FC equipment in the turrets of battleships (you can see the turret computer if you visit USS Massachusetts or USS Salem), and it’s vaguely possible that the stuff in that diagram is the Star Wars equivalent, with the central control located somewhere else. Given sensor advances, you don’t need quite the same layout they used during the dreadnought era.
One of the of the design constraints of Star Trek original series is that the ship has to be discernible in a NTSC screen that is effectively 160 pixels wide and 250 pixels high. This requires broad strokes and unique profiles. If the Klingon Bird-of-Prey and NCC-1701 were both more structurally sound, they would be harder to tell apart on the screen.
But how does it compare to an aircraft carrier. Aren’t these starships mostly used to carry fighters ?
Need to read the article before you come to leave a comment. Our host covers this quickly.
> (As an aside before it comes up: ‘what about aircraft carriers?’ Well, the main armament of an aircraft carrier is its air-wing, which (in its full operation) takes up the entire flight deck, plus the entire hanger deck, both of which in modern carriers run the full length of the ship, plus armory spaces further down and repair and machinery. If anything, an aircraft carrier is more contorted by its main armament than any other modern type of warship.)
If any of the examples were dedicated carriers, they shouldn’t be carrying this heavy a compliment of guns or troops.
What do you think of the Omega Class Destroyer from Babylon 5?
Not OP, but here are my thoughts in this analytical style:
The engines seem properly prominent, with them presumably filling most of the ship’s rear. The back connecting axis is presumably where the reactor is, more or less, along with supply storage of various sorts. The red hatches are anti-ship missiles as well, making good use of the outer surface. This seems to work by OP’s rules.
The central rotating section is mostly the human-habitable parts, which seems much larger than on comparable RL ships. The requirement for artificial gravity through rotation is obviously not one shared by the RL equivalents, so the increased size is likely a result of that (at least in part – at the very least, the radius of rotation needs to be relatively large to get the desired effects without causing vertigo or impossibly fast rotational speeds). As such, while it’s a lot bigger than RL equivalents, it’s less egregious than most sci-fi.
The front is mostly the carrier bay – the recessed bay for fighter launch/recovery at the front is probably backed by the usual hangars, workshops, and such. The series is unclear about internal layout, but this ings true to me.
The guns are much smaller than battleships, but they’re in the right ballpark for something in the pre-dreadnought vein. While they went with a lot of smaller guns rather than a few big ones, the angles of coverage look very reasonable. If we handwave the limits on guns as being spare reactor power rather than gun mass etc. like was the case historically, having an excess of guns with all-around siting isn’t a terrible approach. That said, I’m pretty sure that at least some of those function as “AA” or “CIWS”, not as main battery guns, and I can’t remember the breakdown from the show. The only ones I’m sure are the main batteries are the two pairds of big forward-facing mounts, which is rather anemic-looking. It’s also an unusual location to have your main battery right next to your launch bay.
On the design front, they’re battle-carriers, as is the usual sci-fi approach, which leads to the usual “jack of all trades” concerns. However, combining that with B5 combat, where beam weapons are *extremely* powerful compared to armour (armour basically doesn’t do anything, if it even exists at all), this is a more glaring design flaw than usual. Ships have been chopped in half by beam cannons in a few seconds. In conditions like that, fighters being based on forward platforms like a destroyer is criminal incompetence. These fighters have range for flights of several hours, while the beam weapons seem to only work at visual range. (I know some of this is the effects of filming, because the viewer wants to see the combatants duke it out, but it’s plausible enough for lasers that I won’t quibble much). The designs should certainly split into dedicated carriers and dedicated beam ships – after all, even if there’s no armour worth having, you can at least shed all those carrier facilities, which will protect your ship by making it faster and physically smaller, and thus harder to hit.
Overall, better than most sci-fi, but there’s a few question marks and one big “NO U!”.
IIRC the main gun is a big laser tube running the length of the ship, so I think the intent is that they can’t have many. I forget if the human beams can be fired to different angles. If so, I think that justifies it — no room or power for a lot of lasers, but able to cover a large solid angle with what they do have.
The B5 wiki says we never actually saw it using main weapons, and “The two very large forward cannons mounted under the forward docking bay were intended to launch “gigaton class mines”” It also says the fighters were meant to drop from the rotation section, so maybe the big front hatch is for return docking.
Actually, as someone that went deep into the lore of B5, the Omega class was originally going to be slated as a ‘heavy cruiser’ while the Hyperion class would be downgraded to ‘light cruiser’.
But the hell-storm that was the post-Earth-Minbari War situation for the Earth Alliance sank that rather thoroughly. So they took a classification that wasn’t in use and thus it got stuck.
Also, the main armament of the Omega class is generally around the two fore battle lasers (which have been fluffed to be X-Ray lasers) and the four AFT battle lasers alongside an extensive pulse weapon armament and 72 missile tubes. Also, armor does work in B5, but there are quite a few weapons that literally tell armor to not exist (Minbari Neutron Lasers, for instance, causes whatever it hits to have whatever atoms within the alloys get more neutrons and then quickly undergo fission while Shadow Slicer Beams are matter disruptors), what Earth is best known for is it’s active defense systems in the form of the Interceptor system (a rapid-fire weapon system that disrupts pretty much anything not exotic or lightspeed like lasers) and the accompanying E-WEB system (which is an energy dispersion system, and as long as it isn’t exotic or neutron-based, it lessens the damage).
Of course, one could snark about them being called “destroyers”…
drs: The fluff may have it being a ship-long tube, in which case the axial non-turreted mountings make sense. But the modellers didn’t get the memo, since the guns do stick out from the side of the ship, and in some fight scenes they fire off-axis.
As for “destroyers”, they clearly aren’t using the term in the wet-navy sense, but the wet-navy sense is derived from the literal meaning of “a thing that destroys”. It’s just that “torpedo boat destroyer” got shortened, and the object was lost. You can easily enough come up with an etymology that ignores the Fisherian meaning from the 1890s, just like how “line-of-battle ship” persisted in modified form into the 1940s, despite “line of battle” tactics being obsolete almost a century prior.
(Side note: For some reason I can’t reply directly to you, but only to other posts, which is why this is a self-reply. No idea why.)
Re the postscript, never mind – comments can only nest three deep, and yours are all that deep. The joys of being a newbie…
The Wet Navy has already gotten lost from the original meaning of Destroyer. I’m pretty sure no Burke captain has torpedo boats on his top 10 list of threats to train against.
Line of Battle Ship seemed accurate up until the end though. At Surigao Strait in 1944, Oldendorf did form up into a line of battle with his Pearl Harbor vets that Nelson would have recognized and even managed to cross the IJN’s T.
“Of course, one could snark about them being called “destroyers”…”
It’s so weird that both Star Wars and B5 call obviously capital ships “destroyers”. In both cases, they should reasonably be classified as cruisers or even heavier.
Late to the topic here, but I wonder what Bret would say about the warships of Warhammer 40K. They are intentionally rather absurd, especially the Imperial ships, as 40K is definitely not a hard sci fi setting – the rule of cool (or the rule of grimdark) usually triumphs over all other considerations.
However, Imperial warships to me seem to be well designed for their primary armaments, and those armaments fit the kind of things they expect to fight – they’re not as ridiculous as they first look. The ships are bristling with weaponry, and the broadsides have plenty of space for truly colossal guns with barrels bigger than fighter craft. The physical tabletop models of the ships don’t really do justice to what the lore describes, which makes very clear that there are guns absolutely EVERYWHERE. The whole design is also well optimised for ramming – in a setting where void shields and physical armour are strong enough to resist bombardment heavy enough to flatten a city, throwing the sheer mass of a spaceship the size of a small country at your target is basically the only way to ensure you can actually do massive damage, and the ramming prows are built to ensure that the ship doing the ramming doesn’t destroy itself. I feel this partly justifies the ludicrous scale of capital ships in 40K.
A key lack of realism in these ships is that they generally only have thrusters going in one direction. Having the forward thrusters be the largest and most powerful makes a lot of sense for a ship designed for ramming, but having them be the only thrusters of any significant size (or even the only thrusters at all!) obviously makes no sense for a spaceship. Imperial ships would have to somehow rapidly make a 180° turn and go at full thrust to slow down. It is, however, generally noted within the lore that the ramming-focussed heavy Imperial ships are far less manoeuvrable than those of the Tau or Aeldari (the latter of which can get away with a lot of unrealistic features in their ships because of magic).
The most unrealistic part for me, though, is with heat management. There’s no obvious way for these gigantic ships to vent heat from their normal day to day function (the larger ships hold crews of millions), let alone the operation of thousands of guns (or tens of thousands) at once. Lore generally agrees that the interiors of these ships (outside of officers quarters) are very hot, but realistically they should be totally uninhabitable.
Personally, I don’t understand the purpose of the “chin” at the front, and having an open hangar bay in the business end of the vessel seems like inviting disaster. But the shape is nice, and you have to imagine half is engines and cooling.
Human ships on B-5 have to obey physics, more or less, so having the fighters launched in the direction of battle makes sense to me… is what I was going to say, but then I realized they could just fall off the side, or jet out slowly, then turn and accelerate. But having said that, maybe there are launch catapults on the ship, to save fighter fuel.
The human ships on Babylon-5 seem the “wrapped around a central gun” type, especially the Agamemnon-like ships with their big laser. The older Hyperion (with seat belts!) might have been a box of smaller guns.
The far more advanced Vorlon ships seems dominated by their weapon system too.
The universe maybe has justification for huge all-in-one warships: you need huge engines or Vorlon-level tech to generate a jump point (hyperspace entry or exit point.) So smaller specialists would need to stick close to a capital ship anyway for mobility.
There’s also the cube-square effect: if you need a given thickness of armor for survivability, in a sense it’s more efficient to have that wrap as big a volume as possible, rather than trying to armor smaller ships.
Warships in the webcomic Schlock mercenary tend to be visually dominated by their ‘annie’ plants, which generate superlinearly more power with size, and that power drives both defenses (gravity manipulation) and offense (gravity manipulation plus other stuff). One species’s ships looked like d4s, a huge sphere of annie plant and a little bit of ship stuck on at tetrahedral points.
The ships do tend to have other stuff, especially the big UN warships. Swimming pools, even. But the UN battleplates are high powered and also ‘show the flag’ heavy diplomacy vessels, and the mercenary ships we see are often “you live indefinitely in this”.
“Ships that ply the seas rather than the stars are constrained by the shapes they must have to sail effectively; starships have no such limitations.”
*Fictional* starships have no such limitations. A real starship might. If Alcubierre and White are correct, a future FTL ship will be constrained to the shape of a football while in warp, with the ring containing the exotic matter at the thickest part. (That said exotic matter might be anti-matter presents a different problem, but we’ll leave that aside for now.)
Combine that with the need for heat rejection I mentioned in your previous spaceship post, and now you’ve got “sails” that have to fit into this space while in warp, and then unfurl when you leave (to rid yourself of the heat you build up on the bow of your warp bubble).
The rest of the design gets dictated by your normal-space drive, which might also inform your choice of weapons system. If the EM drive had worked, then you could have a nice propellentless drive powered by the same reactor that handled your warp drive, which would lead to a single laser (as big as you could power) with a targeting mirror on the side of your ship away from the radiator that you keep deployed in combat.
You still have to figure out what to do with that anti-matter in the FTL ring, though.
I’m guessing transfer it out of the ring ASAP, which is probably the best excuse for “it’ll take us twenty more minutes to go to warp, Captain,” that I’ve heard yet.
Any ship with lasers as a significant piece of armament will need a lot of thermal mass, or else you fry yourself after just a couple of shots, so I can excuse the Star Destroyer’s supposed lack of prominent weaponry on the basis that a lot of the apparent bulk is actually just thinly-wrapped lead that’s supporting the actual shooty bit.
Radiators are intrinsically vulnerable in combat and would probably be folded away, and even if they’re extended they still can’t cool you quickly enough to matter in a fight. Even if you’re planning to radiative the heat after the battle, you’ll still need to store it for a little while, hence the need for the big blocks of lead. Having said that, the Star Destroyer passant should be bristlng with radiators to keep itself cool (where, exactly, is the reactor’s waste heat going?) to give its lasers as many shots as possible before they melt, so maybe I shouldn’t be making excuses for it after all…
I read somewhere that the Death Star would have to have an incandescent surface just to radiate away the waste heat from having its habitable sections be lit.
What are your thoughts on the ships in the Honor Harrington universe?
Visual appearance can be misleading.
In your trireme example, the sail is a large part of the silhouette but has nothing to do with the fighting power of the ship. Didn’t galley crews leave the mast and sails behind when they went into battle?
Submarines are generally boring. It’s hard to distinguish visually an attack sub from a cruise missile sub from an ICBM sub, even though they have quite different functions. Modern warships with VLS launchers and stealthy hulls are likewise becoming difficult to tell apart.
The Imperial Star Destroyer is an intimidating monster of a ship. as depicted in the opening scene of Star Wars A New Hope. Potential opponents are not going to hang around for long enough to check the firing arcs of the turbolaser turrets. What more does the Empire need? 🙂
> the sail is a large part of the silhouette but has nothing to do with the fighting power of the ship.
Note that it is coloured as ‘mobility’. It is indeed not the main thing causing speed during combat, and in the case of low wind during combat (and there is ‘low wind’ 95% of the time) you wouldn’t want the sail raised while fighting, but it is an important part of the long-term mobility of the ship: It can take a lot of strain out of moving a ship over the course of days or weeks from your home port to some place where there will be a battle, allowing your men to be more rested and possibly to need less provisions during transit
One thing I feel is missing is *why* are warships and war aircraft so much built around weapons and propulsion? Perhaps it’s obvious to everyone else, but I think a concise paragraph or two about this would help. Here’s how I understand this. I admire brevity but can’t quite master it.
Better weapons give you tactical superiority – you win more fights. Better propulsion also gives a degree of tactical advantage, but most importantly you get to key points on the map faster – to strike or defend them. Focusing on both is the best investment of money if you’re interested in winning battles and wars.
Dedicating a bigger fraction of your space to weapons gives better weapons. More percentage to propulsion – better strategic (map) advantage. Giving more than necessary space for living quarters costs you more materials(therefore money), requires more propulsion to move that mass, and a bigger ship has several inherent disadvantages: bigger target, more space used in a hangar or port, harder to maneuver around in a fleet, harder to concentrate firepower, easier to spot, harder to camouflage (in case of SF – bigger area to cover with shield generators). It’s also debatable if the crew would really be happier in a more luxurious warship if they knew their ship is not as efficient killing machine as it could be, or that their command decided to field fewer warships.
All tre, but that does not mean crew comfort and the rest are unimportant. British ships were built for much longer ranges and a wider variety of conditions (arctic, tropical and temperate) than German ones, for example. This meant more stores and more crew spaces, which meant less internal subdivision, which meant they were more vulnerable to battle damage. On the other hand, they could reach the Far East and fight there.
Likewise, in the sailing navy, British ships were more heavily built than French or Spanish ones. It meant better survivability at sea and less frequent docking for repair, at the cost of less speed.
Spaceships are going to have some crew needs wet navies don’t face – air and water as well as food and, depending on the tech and speed, maybe very long deployment times (months or years).
You could make an interesting point that the more hostile the environment is, the more it pays to have better crew quarters.
I imagine tanks can get away with really cramped spaces, because land is otherwise very human friendly and you can jump out and chill outside as long as you set someone on guard.
Naval ships are harder – you can’t usually go for a swim to relax, however you can still go out on deck and at least see the sky.
Naval ships in arctic/tropical and generally harsher biomes benefit more from more crew space, because it’s often unpleasant outside.
Submarines is where my theory seems to break – I’ll save it for later.
Spaceships – extremely hard and dangerous to go outside and it’s pretty much just the void. Depressingly dull void. You can get basically nothing from outside until you visit a port, and so far we don’t have reusable spacecraft. Space elevators are an immense technical challenge. So everything that provides life support and comfort to crew is pretty much sacred, because that’s ALL you’re going to get and you can only lose it.
I don’t entirely understand why submarines have such crappy crew quarters though. The environment where they move is in some ways deadlier than open space. You can survive a few minutes without a space suit, until your oxygen runs out. High underwater pressure, especially when you enter it abruptly, will kill you in seconds. I’m not aware of submarines you can leave in a diving suit, but I heard astronauts leave space stations and spacecraft pretty much routinely – for example to fix or readjust equipment, or to make some measurements. I suspect submarine crew finds it easier to endure because psychologically they’re closer to safety. You can recover from many kinds of disasters by resurfacing and inflating a lifeboat. If your craft becomes immobilized but hull isn’t seriously damaged you can be rescued by a diving bell or another submarine.
Your theory does not break with submarines, submarines just trade off crew mental (and for that matter physical) health for their operating range and effectiveness. Like, if you talk to USN personnel, a lot of them will agree with the statement that “submariners are all crazy.”
Crew space does matter a lot for crew health, but depending on who is making your military gear some are much more willing to compromise that than others.
Like if we talk about tanks for a second, soviet WW2 tanks are memeticaly famous for supposedly being designed around the assumption that the army is huge and can afford to cherry pick small-statured soldiers to operate the tanks – they lack room for a 6ft tall tanker to fit.
Similarly, USN submarines are arguably designed around the assumption that the navy is big enough that they can cherry pick people with psychologies that can deal with isolation and lack of space. not necessarilly an accurate assumption, as our tools for psychological assessment are not, IMHO, that good.
@Borsukrates With submarines it’s a matter of the limitations of current technology. Every last cubic meter of volume within the (hugely expensive!) pressure hull is precious. Limited tours of duty help as well as the best amenities that can be supplied, like the highest-quality meals in the entire military establishment. Plus the Russian Typhoon class which needed to be huge anyway was remarkably spacious for a submarine.
Bursukrates – the thing about submarines, as I understand it from a (former) nuke…
It’s not that the military doesn’t understand the psychological and morale benefits of room to stand up or move around… when practical. What’s practical for a submarine is still a tiny tube of metal that’s got just enough space for people to do the work they need to without dying in an environment that seems purpose-built by nature to kill them in as many ways as possible.
One of the funny things this made me realize was the the famously peace-loving Federation has much more obvious weapons than the warships like the ISD. Yes, the TOS Enterprise is famously low-detail and designed primarily to be recognizable in black and white on a tiny screen, but the movie version added in visible torpedo tubes and phasers.They’re fairly minimalist as you note. The Enterprise-D, though, has massive phaser arrays as one of its most visible features, and this extends to the Ent-E and Voyager to an extent as well. They don’t look like guns but they still take up a big chunk of the surface area and are located to give overlapping coverage at all angles as a spaceship might need. (They don’t need more because the main constraint is power generation, so a single pahser will do instead of needing to bring many guns to bear at once.) The torpedo tubes are small on the exterior, but the diagrams always show those as just the tips of a multi-deck weapon the size of a football field.
re submarines, diesel-electric ones are incredibly cramped, as propulsion and weapons take up most of the space, there’s a trade-off between size and safety (very large subs submerge slowly and are easier to find). On the up-side, deployments are usually in weeks. Also, crew are selected. IIRC nuclear ones are more specious, as the reactor sets a minimum size for the pressure vessel (I’ve only been in a diesel-electric one).
In my experience, submariners are a special sub-set, like caving enthusiasts and high-divers. If spacecraft had to take a wide range of people, crew amenity would be a key issues.
All submarines are incredibly cramped, because they have to be neutrally buoyant. This is way denser than a typical ship (IIRC, a battleship has an average specific gravity of something like .6, and most modern warships are way lower) and any extra space is going to need to be paid for with extra weight, so the designers shave as much as they can. Nautilus (the only nuclear sub I’ve been on) was only very slightly less cramped than a US WWII fleet boat, and those are relatively palatial compared to U-boats of a similar era.
I know this is focused on capital ships but the fighters in most sci-fi universes have always bugged me. They are almost always designed like a terrestrial fighter plane. The B5 star fury is one of the few I can think of that actually looks like it was meant for zero-g combat.
In Star Wars, this is by design – combat is *supposed* to feel like WW2 naval combat (which is also why fighters are so dominant). The X-Wing design is based on doing weird things to a P-47.
What you are calling “engines” on Star Trek vessels are actually the warp nacelles. These are the devices that generate the warp field. They are fed energy by the real engine – the warp core, hidden in the bowels of the ship (just about the only major component that is NOT externally visible). The warp nacelles are like the tires on your car, while the warp core is the engine under the hood. You wouldn’t say that a car has four large prominent “engines” on each corner of the vehicle.
If you’re going to be getting into the nitty-gritty of starship design then a most excellent resource is Atomic Rockets of the Spaceship Patrol: http://www.projectrho.com/public_html/rocket/
That site uses real scientific principles in discussing spacecraft design, and has pages upon pages on real life ship designs and the impact of particular design choices on science fiction stories.
Hah, late to the party here.
There’s a semi-obvious technical explanation for keeping the propulsion system, particularly ones designed for the vacuum of space, as close to the exterior as possible — heat management.
Getting rid of waste heat in space is hard, and if your source is buried deep inside your spacecraft, it gets much harder to dump heat to whatever radiator system you have.
Starships in Star Wars are wielding their reactors as weapons; main and secondary reactors dominate the volume of military craft; and in the ISD’s case, most of the spacecraft is propulsion even in ICS. It’s a post-facto rationalization, but one that’s relatively simple and makes big space warships make some kind of sense. Big warship, bigger reactor, more firepower.
The emitters are small relative to the reactor.
You should see Fractalsponge’s stuff. He builds on the design logic of Star Wars warships to craft amazing-looking spacecraft.
In defense of skinny cylinders, under certain constraints they are the best shape for getting from point A to point B at speed. Specifically, if the speed a spacecraft is traveling at is high enough and the space it’s moving through dense enough, a low cross-section makes point defense far more manageable. In extreme situations, a degree of streamlining may be helpful to reduce drag from loose hydrogen atoms and the like. In hard sci-fi this should only apply to relativistic spacecraft, of course, and if it affects warships it should affect all spacecraft in a setting (which travel similar distances/speeds).
In defense of the “jack of all trades” issue, part of the problem is space is really REALLY big. Most of today’s specialist warship designs get away with being specialized because they’re working in fleet groups where the specialized design needed will be right there traveling with you. In space you’ve got a ridiculously large volume to work with, and unlike modern wet navies where the distances are such one group can effectively cover or at least respond to a fairly large batch of national areas within a reasonable time frame, starship “zones of control” seem to be solar system scale most of the time. Unless you just guard a very small fraction of your territory, to get enough coverage you probably have to accept a fairly large strategic dispersal as a given (i.e. Star Trek’s “we’re the only ship in the quadrant” might not be implausible writing). Add in even the fastest FTL travel times seem to assume hours between star systems at best, and in a crisis you probably only have what’s there available. So, if ship designs don’t take a “pack everything with you that you can” approach to various capabilities, they’re basically accepting those capacities will not be available on any sort of immediate basis. A Star Destroyer or whatever might not be up to the level of having dedicated troop transports and carriers escorted by gunships, but it’s much easier to make the one ship than fleets and have SOME capability there when you need it.
> This isn’t a dedicated carrier, at least according to its wiki article.
A note; based on the design of the hangar bays, it appears that they were a casualty of the Raddus’s scrapyard rescue status, and used to be larger, filling that whole gap we see in the film. Therefore, it would be reasonable to propose that a full-complement Raddus would be a cruiser-carrier, a long-operating capship meant to form the core of a task force out in the wilds of the galaxy.
It was always clear to me that a big part of the pre-CGI logic of having small main batteries was to save production time; if you have to account for the facing and elevation of gun turrets in your shots, it’s harder to reuse footage, and for that matter, it’s harder to shoot in the first place; bonk one gun on one turret out of alignment, and you’re going to have to reshoot that.
Now, of course, who cares, because CGI allows you to have however many turrets you need and to produce your FX shots to order in a short and above all predictable time – but the legacy of that production need has stuck with us.
My favorite handwave for why spaceships have cool shapes comes from the webcomic Crimson Dark. FTL-capable ships need “stabilizers” – large wing-like panels that allow the ship to pass safely through jump space. Stabilizer design is very complicated and technobabble-y, meaning they come in all sorts of shapes and sizes, which justifies the artist designing the ship around a cool shape and then filling in the guns and living spaces later.
The stabilizers also provide a nice big area for ships to take dramatic damage to their armor without injuring the people on board, since they’re almost literally just big slabs of metal. Damage to the stabilizers can prevent the ship from jumping, but that’s something they only need to worry about after they survive the battle.
As other commenters have noted, the need to store fuel predominates for spacecraft to an extent it does not for ocean-going vessels. With nothing to “push against”, and nothing you can take in to use as fuel, you need both reaction mass and stored energy with which to accelerate it. Compare the mass of fuel vs. vessel on the Saturn V to that of a 19th-century battleship and the qualitative difference becomes apparent. Hence, it seems likely that (using the example you gave) most of that seemingly empty mass in the Star Destroyer is needed to hold massive quantities of fuel.
“..everything but the reactor powering the damn thing”
Bingo! you said it yourself. What powers these things and where is the heat management system? those might be huge and having the rector bulge out the bottom (is there a bottom in space?) might be the only way to radiate enough heat without cooking the crew
maybe if big parts of the ship is empty nothing… that might be a key component of the heat management system; tanks of some frozen solid or cryogenic liquid that can be heated and maybe even vented to space when you start firing those multi GW lasers at high rates while poring on the Delta V and taking incoming fire. Thermodynamics is a harsh mistress.
Wet navy ships look the way they do because they operate at the water/air interface. in space, it’s space all round. there is no need for fighters other than for the hero to be cool; bigger is better because it provides interrail stability and thermal mass and since everything is traveling in the same medium there is no smaller equals faster/more agile.
I know that there there is a lot of Handwavium in Sci-Fi and its done to sell movie tickets but of all the problems I have with spaceship design, the size of their shooters is low on the list. 😉
I feel like the reasons that scifi warships never make any sense is because the underlying idea of interstellar war doesn’t make any sense. If relativity holds, space wars are not fought over weeks, or months, or years; they are fought over eons. (And as easy as it is to dismiss “if relativity holds”‘ we’re talking about something more validated than anything in metallurgy or ballistics– this is not some modern fad!). And by the time we get where we’re going, our spaceship is a weapon of mass destruction in and of itself. Putting guns on it would be like strapping machineguns to a nuclear ICBM.
What about wormholes, or alcubierre drives? If those are ever possible, it is because relativity holds, and if relativity holds, the way to use these tchnologies is not to snd guns someplace really fast, but to break causality, by travelling to a position and velocity that allows you to snd messages that arrive before you left.
It seems to me that scifi space war is a disagreement between those who think that future war will be like WWII (star wars etc) and those who think it will be like WWI (more star trek etc.). Neither seems likely to me. To the extent that space war will be predictable, I instaed believe that it wil be like WWIII. It will be fought with proxy wars, with espionage, cyber warfare, and agitation, all under the constant threat of weapons of mass destruction. And to the extent that it is not predictable, I think we need to consider that advances in propulsion or weaponry are not going to come independent of other tech, tech like mind reading and mind control. It is very hard for me to imagine how any popular dpiction of space war is remotely realistic. In that context, arguing about where the gun battery goes feels a little bit like complaining about how realistic a road runner cartoon is.