The industrial capacity of an Imperium

[IronStar]

Many wh40 k sources say about forge worlds, hive worlds and other worlds to have huge industrial capacity and continent- spanning factories to meet demands of the imperium s armies. But how much is it? Well, factories of such immense scale are not joke at all, and it became interesting for me- what is an approximate rate of production of a forge world? Well, sources dont say anything precise- only smth like "thousands upon thousands" stuff and etc. It is also interesting for me in scope of information that mechanised regiments are very rare in imperium, which was kinda strange- damn, they have planet-sized factories, how can they ever be short of that stuff?(howewer ithere are many ways for an imperial army to find itself underequiped even given plenty of stuff produced but thats another question).
So, i decided to make some calcs. Please bear in mind that i am actually shitty in maths, so no wonder if all my calcs vere actually screwed- up. And yeah, the following calcs are VERY conservative.

And, lets begin.
How many leman russ tanks can forgeworld produce? To answer this question, lets assume that it takes FW to build a leman russ the same time and effort it takes USA to build M1A1 abrams. i took a Lima Army Tank Plant and its M1A1 abrams production output in 1986(http://www.globalsecurity.org/military/ ... y/lima.htm)

It could produce 120 tanks per month or 1440 per year given 950,000 square feets(88 square km) occupied by its main manufactoring buildings(i ll increase it to 92 square km given that there are other important facilities)
We have 92 square km of buildings to produce 1440 tanks per year.
Most sources say, that forgeworlds have "continent spanning factories"(which is also proved by some arts)
so lets take Australia which occupies an area of 7692024 square km. Tanks production as well as production of other machines needs a lot of other facilities to manufacture parts and materials, and becauss its quite difficult to to find out all that stuff including specs of each factory, i ll just take it as a half of a continent.
Now we have 3846012 square km for factories, 3846012/92= 41804 and that is the number of factories that can occupy that territory.

But not so fast. There are workers on each, and they need somewhere to live(even on forgeworld).
Staff of lima factory in 1986- 4000 but I ll take 6000 in this case assuming that FW has lower productivity (actually I don’t agree with this but many will)
So it gives us about 250 000 000 workers. To calculate required area well take new york as a template
Area is 800 square km with pop about 8000000 and pop density of 10 000 per square km
Lets assume that pop density of forge world hivess is …..100000 per sq km(its may be wery weird but I assume horrific living conditions even shittier than hives and vast skyscrapers and underground construction with GRIMDARK included of course)
So we ll have 80000000 per 800 square km city and about 3000 square km MIN for workers to live in(I ll take 3200 for four such hives)
So 3846012- 3200= 3842812
3842812/92=41769
So we have 41 769 factories on territory left
1440 tanks a year per factory * 41769=60147360 tanks per year or 5012280 tanks per month.
Well, thats impressive, but bear in mind that factories on FW do not enjoy planet sufrace only and extend both undeground and up.

Assume that factory compex height is 30 m. Lets have 1km tall factory 1000m/30= 33 factories on top of each other and the same 1000 m underground too so 66 total
41769 *66= 2756754 factories
They ll need 16540524000 workers…oh shit
With our hive cities with 80000000 per city we ll need 206 such cities 800*206= 164800 square km s
I ll wont consider it now and I ll just count how many tanks we can produce
So 1440 *2756754=3969725760 tanks per year or 330810480 per month. Well…..thats a lot
And at last- if we assume that there are 1000 forge worlds and every has at least that amount of factories
3969725760000 so we have almost 4 trillions leman russes per year.
That also might be used to calc aprroximate number and size of transports to carry them but thats too difficult for me.
You may argue that lemans are lower tech generally than modern tanks- maybe, but M1A1 is just first mbt i could find exact factory dimensions and specs for.
And bear in mind that these calcs were made assuming lower productivity than in 1986, what i actually don t agree with and think to be far highter on forgeworlds.


And theres another issue and its about Imperium shipbuilding. I know that some of that was already discussed but i still want to add smth to this.
First- there are some exact numbers in BFG- 11 years for a cruiser on a primordial world(i think actual assemby time to be far less here) 1 year for an escort, and even some info about fleet replacements arriving in months(howewer there were some bits about far longer timeframes) and that was retconned in battlefleet koronus that states silly stuff anything larger that escort to take frigging centuries to build, but i think that it can be handwawed:
1) worlds are not specified- difference between some hive or pre-hive world and shipyard world can be gross
2) supplies- thre are a lot of resources needed and these must be transported to destinatoin, and given that some non qualified for shipbuilding world can be ordered to build it as a part of tithe- it can actually be icapable to manufacture most parts and wait for them and resources to be brought from somewhere else, ang given slow and unpredictable warp travel with possibility of pirate raids - century for to build a ship can be possible.
Anyway, i don t believe that imperium(and forge worlds especially) has THAT low indusrial capacity.

[Sea Skimmer]

A facility like the Lima tank plant doesn't make all the components of the vehicle, actually it basically cuts and welds together the hull and turret from steel plates, and almost everything else comes from other plants in a finished state. Engine, transmission, gun, electronics, non steel armoring. Its not a mere assembly facility, but certainly not representative of the space required to manufacture such a complex weapon from scratch. The Russian Uralvagonzavod plant at at Nizhny Tagil is closer to what you'd need for a total conversion tank plant, and completely dwarfs Lima. You also going to need a huge amount of space for air, water and transportation systems if you had anything like 1km thick factory let alone over a continent span, it'd have to be near close loop operations. That's going to eat a huge amount of space, and power.

Given the way 40K is written about productivity is probably incredibly bad, and quality control even worse leading to millions of rejected tanks with broken drive sprockets and cracked armor choking the transportation system to the point that trainloads of key parts, like firing pins, are held up for centuries trapped and derailed inside poorly maintained tunnels from which no escape is possible, while broken air and water systems have rendered all the lower levels uninhabitable, half flooded and fit only for salvage by suicide squads. Just because they have huge factories doesn't mean they are functional. Also the writers are dumb on average.

[TimothyC]

You've made a simple conversion mistake early in your work. I've seen the Lima plant (by seen I mean I've driven past it - you get off I-75 at Exit 120, you go west to Dixie highway, you take that north to Buckeye road, and then you go west), and it's no where near 88 square kilometers. It's less than one tenth of a square kilometer (you are off by a factor of a thousand).

[IronStar]

A facility like the Lima tank plant doesn't make all the components of the vehicle, actually it basically cuts and welds together the hull and turret from steel plates, and almost everything else comes from other plants in a finished state.

I think you missed some details in my post, cause:

Tanks production as well as production of other machines needs a lot of other facilities to manufacture parts and materials, and because its quite difficult to to find out all that stuff including specs of each factory, i ll just take it as a half of a continent.
Now we have 3846012 square km for factories, 3846012/92= 41804 and that is the number of factories that can occupy that territory.

i ve already considered that and yes, thats very conservative

Given the way 40K is written about productivity is probably incredibly bad, and quality control even worse leading to millions of rejected tanks

where is it from?

while broken air and water systems have rendered all the lower levels uninhabitable, half flooded and fit only for salvage by suicide squads

And again, you missed some details, cause despite i mentioned hive worlds(and you re talking about them here)
these calcs are for forgeworlds, and thats completely different story. I mentioned that i think productivity on forgeworlds be far highter, and there are good grounds for it, because AdMech run everything there, and they re care about how the machines are produced so quality control must be good, and theres extensive automation too(many sources describe insane servitors amount, and inquisitor rulebook states that there are more servitors on forgeworlds than workers- that is many billions easily), and workforce not only even cheaper and deprived than on hive worlds but also according to some sources massively augmented. And bear in mind that theres AdMech personell too, and theres plenty of lower ranks that actually take part in manufacture and are augmented even more.
And something else- wh40k is extremely inconsistent, you must know that, and trying to generalise stuff is a bad idea(i ve tried and failed)

Also the writers are dumb on average

Oh, thats where i agree completely. Yes, they can write good stories but when it comes to details......
Imperial amour is first to come in mind.

You've made a simple conversion mistake early in your work. I've seen the Lima plant (by seen I mean I've driven past it - you get off I-75 at Exit 120, you go west to Dixie highway, you take that north to Buckeye road, and then you go west), and it's no where near 88 square kilometers. It's less than one tenth of a square kilometer (you are off by a factor of a thousand).

As i said in the beginning, i could make a mistake. i ve tried to find some photographs of complex itself but failed, so i ve just took numbers from article (http://www.globalsecurity.org/military/ ... y/lima.htm)
Maybe i took wrong ones

[TimothyC]

As i said in the beginning, i could make a mistake. I've tried to find some photographs of complex itself but failed, so I've just took numbers from article (http://www.globalsecurity.org/military/ ... y/lima.htm)
Maybe i took wrong ones

You took the right number - you just did the conversion wrong. The square footage for the given complex is only 0.088 square kilometers.

[IronStar]

You took the right number - you just did the conversion wrong. The square footage for the given complex is only 0.088 square kilometers.

I see. Actually, i supposed that i ve made some fundamental mistake( i am quite bad at maths as i said), but that still gives at least some understanding of scale. I ll recalc a bit later.
0.088 square kilometers- so, actual assembly is not even a 1 square km....it appears that these 950,000 square feet are smth like a volumne- i was confused by "30 football fields" comprassion.
And will it give 2 square km at least given railroad network, test track and other facilities besides assembly?
Thanks for comments and pointing at errors.

[fgalkin]

Given the way 40K is written about productivity is probably incredibly bad, and quality control even worse leading to millions of rejected tanks with broken drive sprockets and cracked armor choking the transportation system to the point that trainloads of key parts, like firing pins, are held up for centuries trapped and derailed inside poorly maintained tunnels from which no escape is possible, while broken air and water systems have rendered all the lower levels uninhabitable, half flooded and fit only for salvage by suicide squads. Just because they have huge factories doesn't mean they are functional. Also the writers are dumb on average.

Given the deliberate simplicity of the Leman Russ and Chimera and that their production process is still somewhat automated due to servitors and such, I doubt that their quality control issues are worse than, say, the T-34s produced in '41 and '42.

Now, the advanced stuff like Baneblades and all those beam cannon variants of the common stuff, are a different story entirely- there is a reason why their yearly production output is measured in the dozens or hundreds, or they are one-of-a-kind and no longer replaceable.

Supply issues of key components are probably a far greater hindrance to the Imperium's productivity than quality control, given the inherent unreliability of warp travel and the fact that they probably have to pass near at least one war zone. That's another reason why the Imperial Guard's equipment being so backwards and simple compared to the Imperium's high-end stuff makes sense- it is designed to be manufactured, start to finish on a single world, with a mimimal use of the interstellar economy.

Have a very nice day.
-fgalkin

[IronStar]

Supply issues of key components are probably a far greater hindrance to the Imperium's productivity than quality control, given the inherent unreliability of warp travel and the fact that they probably have to pass near at least one war zone. That's another reason why the Imperial Guard's equipment being so backwards and simple compared to the Imperium's high-end stuff makes sense- it is designed to be manufactured, start to finish on a single world, with a mimimal use of the interstellar economy.

Thats exactly what i am thinking about, also- given enormous variety in industry and culture of imperim, stuff must be easily repairable on any planet with any materials aviable and simply enough so even some barbarian could be trained to handle it as soon as possible.
but theres more- another major problem of guard s underequipment is a Deparament munitorum- not commanders, but they decide what weapons do the guard use, what ven do they ride(and do they need to ride smth at all), what do they wear and what do they eat, and they tend to value the shittiest lasgun more than a guardsman wielding it, and, after considering details of conflict, they theoretically can even decide that guardsman doesnt need it and can succesfully complete objective without it(hell, on vraks munitorum didnt issue kriegers even shit flak armor, cause 'we ve came to conclusion that you dont need it). So i think that there is far more neat stuff like plasmaguns, caparace and baneblades, but they are not issued and are stockpiled in munitorum reserves(theres even such type of worlds commonly mentioned as warehouse worlds).

Another wery interesting detail, proving the point- information about cadian regiments s supply from IA 11- as you know, they are among the most well equipped from guard, and thats because 1) they have their own factories 2) when they need some forge world suff, they order it directly without munitorum