Grand 40K Quantification Thread

[18-Till-I-Die]

In Necropolis is mentions them deploying no less than ten thousand ships in a single invasion, to be precise:

"The awesome power of the Imperium was there for every Verghastite to see: ten thousand ships...(it goes on to describe their appearance). Macaroth unleashed his might on the planet below. Six million Imperial Guardsmen, half a million tanks, squads drawn from three Chapters of the Adeptus Astartes, and two Titan Legions."

Pages 309-310 of Necropolis.

Some hard numbers here--
10,000 ships at least
6,000,000 men
500,000 tanks
And two (presumably full strength) Titan Legions

An unknon number of Space Marines were involved, but i would presume at least a company strength force, drawn from three Chapters, seems reasonable.

[NecronLord]

Edit: By the way:

Enormous fleshhounds of Khorne loped forward in their wake. Titans armed with specially constructed siege weapons lumbered inte position. Battle cruisers dropped megatons of explosive death onto the defenders.

This comes from page 14 of the Horus Heresy rulebook.

I think that one's a bit redundant though, as it doesn't specify anything in particular, and we know they can do megatons anyway.

[Lost Soal]

Edit. I fucked up and calculated using a galactic radius of 45,000 instead of 35,000. Truly sorry. I'm reposting with the corrected figures. Please feel free to delete the original

General Technology: Industry & Scope of Operations:

Fleet Numbers of the Imperial Navy

From the Battlefleet Gothic Rulebook pg86

All human-inhabited space is further broken down into sectors, which are most usually cubes of space roughly 200 light years to a side.

Each battlefleet normally consists of between 50 and 75 warships of varying size, although in some sectors this will be more or less, according to the importance of the sector and the number of
enemies it must contend with. As well as these destroyers, frigates, cruisers and battleships, a battlefleet also has access to countless smaller
vessels such as transports, shuttles, messenger craft and long-range patrol craft. In addition to interstellar vessels, a sector will also be protected by numerous ships incapable of warp travel, such
as system patrol ships and defence monitors.
These are backed up by stationary defences – space stations, orbital defence platforms, groundbased defence lasers and missile silos and orbital mines.

According to this site the Milky Way galaxy has a disc thickness of 2,000LY and a Nucleus thickness of 20,000LY

So taking this and assuming a Galaxy of 70,000LY in diameter and 2,000LY thick (ignoring the Nucleus);
We get a volume of ~1.539E+13LY
A Sector has a volume of 8,000,000LY
Giving ~1,924,225 Sectors across the galaxy

This allows us to get rough ranges of the total fleet size of the Imperial Navy, Assuming Imperium Presense of:
1%= Between 962,112 & 1,443,169
5%= Between 4,810,563 & 7,215,845
25%= Between 24,052,818 & 36,079,228

This is in addition to the fleets belonging to the Astartes, Adeptus Mechanicus and the Inquisition.

NecronLord. Bearing in mind the new figures, the most likely numbers would be for a presense of between 1% and 5%. The Imperiums apparent inability to place a ship at every planet is easily explained by the very tagline of the 40K universe.

There is only war, and large portions of the Navy are involved in the act of making war, rather than defending individual planets. Sabbat worlds, 13th Crusade, battle for Armageddon, each of these conflicts will drag the Navy away from protecting planets. And these are just a tiny fraction of the wars which GW has brought to our attention, I find it unlikely for instance, that during the Sabbat Worlds Crusade there were no other wars, crusades, or invading forces to fight off.

Patrols. The Navy patrols many areas which do not have IoM planets in them ion order to keep watch on Xenos and prevent illegal trading. There are also quarantined zones, for example in Ravenor an entire system is under quarantine and guarded by the Navy after a warp storm errupted and killed everyone in the system, leaving the worlds saturated with Chaos.

Strategic Worlds. Terra, Armageddon, Cadia, Gudrun; if your going to have fleets of at least 10-30 ships perminantly stationed in one system to protect areas of vital interest then other worlds are going to have to go without.

Damage. As I recall there are mentions of ships being out of service and under repair for decades at a time following a major conflict, this would reduce effective fleet sizes even further.

[Vehrec]

Strategic worlds like Terra and Cadia probably have minimum of 1000 ships on station in system and ready for combat at all times. We don't want those dirty chaos scum getting out or anyone getting to the Emperor, now do we? And maintainance probably does consume a large part of a ship's life, although not more than about 10% if you want to be realistic. These ships do have their own foundries for opperational repairs.
I tend to favor a number of about 500,000 as a minimum, based on the fact that there aren't enough ships to go around and the whole 'million worlds' thing.

[Imperial Overlord]

Remember, only Imperial controlled space is broken down into sectors. Ork space, Tau Space, Eye of Terror, etcetera don't count for this although uninhabited systems nominally under Imperial control do. Quantifying the number of sectors is going to be hard.

[Connor MacLeod]

Edit: By the way:

Enormous fleshhounds of Khorne loped forward in their wake. Titans armed with specially constructed siege weapons lumbered inte position. Battle cruisers dropped megatons of explosive death onto the defenders.

This comes from page 14 of the Horus Heresy rulebook.

I think that one's a bit redundant though, as it doesn't specify anything in particular, and we know they can do megatons anyway.

But its indicative to some degree of the sort of firepower that can get tossed around in grgound combats (or gets needed to be tossed around, much less.) Which is relevant.

[Connor MacLeod]

Anyhow, speaking of ground firepower:

Re-laying the gun took a vital second. In that time, the second tank fired again and hit the Wrath squarely. The impact was enough to lurch all sixty-two tonnes of armoured machine several metres sideways. But it didn't penetrate the twenty centimetre-thick armour skin. Inside, the crew were dazed and they'd lost most of the forward scopes.

This was posted a long time back by Black Admiral, so I don't know who was doing the firing (I don't remember, that is. I know it was stated before.)

There are two interesting details we can derive from this:

1.) The momentum of the tank gun hitting the wraith. The mass of the tank is given (62,000 kg) and the distance shoved is given (2-3 meters, roughly) and the duration thiis all occurs in is also given (no more than a second, possibly less.)

The absolute low-end momentum of the impact is 124,000 kg*m/s (62 tons x 2 m/s sideways velocity. ) This is conservative IMHO for several reasons:

1 - duration, as I noted, is no more than 1 second, but could be much less (half a second, for example.)

2 - this assumes a perfectly side-on hit. If the impactor hits at an angle, its possible that in addition to the sideways momentum, the tank is also pushed downward against the ground.

That said, it can be noted in general that this is indicative of impactor resistance in the hundreds of thousands of kg*m/s. Its a bit harder to pin down KE, but we can make some very generous assumptions.

Assuming a 100 kg projectile (rather generous for a tank, IMHO), the velocity of the round must be on the order of 1.24 km/s (about what a modern tank can achieve.) The KE for such a round would be 76.8 megajoules, low end.

At a higher velocity and lower mass (say 40 kg and 3.1 km/s) KE is some 192 megajoules.

Assuming a 200,000 kg*m/s momentum, and a 20 kg round (as a third example) means a velocity of aroudn 10 km/s yields a KE of around one gigajoule.

2.) Tank durability. This gives us a good benchmark for the durability of IoM tanks against physical impactors (KE and momenntum) 20 cm of forward armor plating could survive the impact of the given amount of momentum above.

When it fired, the breech of the main gun hurtled back into the turret space with one hundred and ninety tonnes of recoil force.

according to here a "ton" (or rather specificlaly a "ton-force") is worth roughly 9,000-10,000 newtons (might be higher - a few people I've known have hinted it might be 20,000+ newtons, but I can't confirm that)

190 "tons-force" x 9,000-10,000 yields a recoil of around at least 1,710,000-1,900,000 newtons. Assuming roughly one second duration, this might correspond to roughly several million kg*m/s worth of momentum.. fully an order of magnitude greater than the prior calc. (This is also enough to send a 62,000 ton tank recoiling back at over 115 km/hr, I should note )

That said, the KE for the round would also be SUBSTANTIALLY higher. (assuming a 500 kg projectile, and a 4 km/s muzzle velocity, we're talking over 4 gigajoules worth of KE.

The first calc is roughly equivalent to a projectile (or projectile salvo!) by the 8 inch guns of a WW2 era heavy cruiser. The second calc is even more amazing - that's easily equal to a single heavy gun on a WW2 battleship.

That's not all though. Replace the projectile cannon with a nother weapon (say a large lasgun) and the weapon could, theoretically withstand the recoil of a 570 TW laser (nearly 140 kilotons!) At the low end, it should demonstrate concistently that energy weaponry on a tank should be generating at least hundreds of megajoules, if not thousands. This also goes for hand-held cannons like lascannons, meltas/multimeltas, etc.

[Connor MacLeod]

Note: Black Admiral also mentioned that the novels "Grey Knights" and "Iron Hands" both mention boltguns having a recoil that would break a normal human arm (a Grey Knight's boltgun in the first example, and Iron-Father Gdolkin's boltpistol in the second example)

If we can get the quotes and guesstimate the mass of the round (I'm guessing 50 grams to 100 grams probably) the velocity of the round could be estimated (hundreds of m/s low-end I'm guessing, again) and its approximate KE (about equal to a .50 cal gun in my estimation, disregarding the explosive effect.)

As an aside: I've read on wikipedia entries for 40K that a lasgun is supposedly capable of taking the limb (arm/leg) off of an unarmoed human being in one shot. Is there a source for this that anyone can corroborate? If so it might be a calcable event.


Edit: someone mentioned accecleration figures for starships.. if you have them, post the details and we can work that out.. and then maybe come up with some corroborating nova cannon calcs.

Edit again: White Rabbit did a bombardment cannon calc here

[Connor MacLeod]

a few random BFG quotes:

The actual base of a ship model represents very close range around the ship, no more than a few thousand kilometers

"close range" is considered to be a few thousand kilometers. If one were inclined towards game mechanics, one might be able to measure the radius of a warship base and then scale the gun ranges off of that (I am under the impression this sort of scaling could be considered fairly reliable, since most ranges are measured in cms for example, if the base reprensets a 1 cm diameter, then 4,000-10,000 km (dependin on how liberally you define "several") would equal one cm on the board. At the very least it should be suggestive of the "hundreds of thousands of kilometers" implied by the "leagues" comment.

Battleships are the largest fighting ships in space. They can absorb a tremendous amount of damage and mount weapons batteries capable of laying waste to entire continents.

The above implies that the broadsides weapons batteries are collectively (per broadside) possessing enough energgy to level a continent (implying somewhere on the 1e7-1e8 megaton.. Ie 10-100 TT) firepower estimate. The only problem is number of shots required. The quote could be interpreted to imply a "one shot" deal, but that's not certain.

Direct fire attacks include weapons such as lasers, fusion beams, and plasma launchers which when fired hit almost immediately, even across tens of thousands of kilometers.

Implies a "minimum" weapons range of tens of thousands of kilometers. Note that I say "minimum" because the implication is that they almost "immediately" hit - given the velocity of some weapons such as lasers, they could still arguably be "direct fire" out to about a light second or so (depending on how you define "almost immediately".)

[Connor MacLeod]

Sabbat Worlds Crusade, and the Gaunts Ghosts books, give some good idea of scale of the Imperium itself, at least one sector of the Imperium. Would that information be applicable or do we only post tech info here? Maybe in the misc listings? It also gives some good, solid idea of weapons and scale of the Imperial Guard.

Go ahead. AS soon as I get around to it I'm gonna starrt digging up some stuff on Imperial Guard numbers too, hopefully.

[Connor MacLeod]

The second report of Abbadon's Planet Killer's attack on Savaven, from "Warp Storm":

Abbadon uses Savaven as a trial for the planet killer, destroying the planet in less than an hour and kililng fourteen billion people.

Note that this indicates that the timeframe for the planet killer as given in BFG is roughly accurate.

Unfortunately, no reliable assay has been made of the vessel's size, but it is without doubt significantly larger than our battleship classes. Captain Vinrex of the Felicitas estimated gross displacement as being in exess of 400 million!

Note a guess about the dimensions and tonnage of the Planet Killer (units aren't known, but given that it refers to "displacement" and the usage of general real life terms, we could assume "tons" as an accurate unit of measure. This might, in turn, provide a potentail benchmark/estimate for warship masses.)

An aura of energy built up around the core of the ship, a storm of lightning arced from the edges of teh aperture until, with a blinding flash that eclipsed the light of Savavens star, the Planet Killer fired. A storm of destruction struck Savaven, its atmosphere began to boil away,[ the immeasurably powerful beam boring through its crust causing earthquakes and tidal waves to sweep across the Cardinal world's surface. The ice caps began to melt and chains of dorman volcanoes erupted across the globe, ,vaporizing the seas and sending socrching steam billowing into the air. With a continent-sized detonation, the planet's core erupted, the massive release of energy thrusting the planet out of orbit and sending it spinning wildly off its axis. with a final death-spasm, Savaen disintegrated into a billion shareds of molten rock, which spread across the heavens like glowing dust.

Notes:

1. - atmosphere boiling off (or rather, beginning to.boil off due to bombardment. Note that, as calculated, this requires around 3-4e27 joules for an earthlike planet.

There is one mitigating factor that can increase this figure significantly - the subsequent mention of "Vaporizing oceans", that the planets water content became part of the atmosphere. If the atmosphere has not been totally removed at htis point (quite plausible) then it is possible that much if not all of the water vapor then becomes part of said atmosphere, which would serve to increase the energy requirement to "boil off" the atmosphere. Using the 1.4e21 kg figure from the previous Planet killer analysis, it would require approximately 8.5e28 joules of energy to evacuate the atmosphere PLUS water vapor, a figure which closely corresponds to my upper-limit calcs from before.

2 -Confirmation of the ice caps melting (and this also occuring prior to the oceans vaporizing as described below)

3 - confirmation fo the oceans vaporizing, thus confirming my initial estimate of that.

4 - a "continent sized detonation" that knocks the world off its axis before it seemingly "shatters" into what appears to be a mass-scattering event. Note that some of the ways in which this incident is phrased just "scream" technobabble, but if we decided to treat it somewhat figuratively, we could assume that instead the massive influx of energy caused massive plumes of ejecta to be shot up into space.

Assumign that a continent-sized hole worth of the crust and core (to a depth of around 6300 km or so) were ejected form the planet at escape velocity requires an enegy input of 3e31 joules. The energy for the crust alone is insiginificant compared to this: ~5.6e28 joules.

Note that this last calc should be taken with a MAJOR grain of salt. The surface/core/etc should not have spontaneously "detonated" , like that.. the energy input over half an hour would have resulted in a sustained acceleration. (there is also the small problem that the Planet Killer would be in the path of this ejecta, exposing it to unneccesary damage.)

And unless the beam were VERY efficient, its likely that a great deal of energy over the half-hour period would have also vaporized substantial portions of the planet. (given the secondary effects - oceans vaporizing, the atmosphere boiling off, and ice caps melting as well as the quakes and tidal waves, its rather unlikely that the beam was very efficient.)

And of course, it also assumes that all the mass in the given volume was used as ejecta, which may not be the case (other ejecta might contribute to global firestorms, dust loading, etc.)

(oh and if you're curious, 3e31 joules of KE corresponds to a momentum for the ejecta of around 3e27 kg*m/s.. enough to impart a velocity of hundreds of meters (1 km tops) to the mass of an Earthlike planet.. not quite enough, I think, to "flip a planet over on its axis." and at any speeds taht could reasonably achieve that, mass scattering would occur (and quite a bit sooner at higher levels.)

[Connor MacLeod]

regarding fleet sizes: Maybe a better idea is to estimate the average number of worlds per sector and then infer an idea of how many sectors there are.

I should also note that "millions" of warships is a tad hard to reconcile with the evident "thousands" of warships stated in other sources like BFG I believe. millions =/= thousands

[18-Till-I-Die]

I found something i think may help with determining how much of the galaxy the Imperium covers, and thus the sectors, fleets etc...

http://www.joachim-adomeit.de/wh40k/spacemap/map.html

Hope this helps, but just at a glance...the Imperium covers a huge area of the galaxy, almost all of it.

It looks all small at first, but then scoll down or right and you'll see the whole map, its huge.

[The Grim Squeaker]

I found something i think may help with determining how much of the galaxy the Imperium covers, and thus the sectors, fleets etc...

http://www.joachim-adomeit.de/wh40k/spacemap/map.html

Hope this helps, but just at a glance...the Imperium covers a huge area of the galaxy, almost all of it.

It looks all small at first, but then scoll down or right and you'll see the whole map, its huge.

You Do Know that space is 3 dimensional right?
Are all the controlled areas true 3d 200 ly cubes? (or are some relatively 2d? which seems to be the case with some, Cadia for example)

Also on a sidenote The Storm of the Emperor's wrath is fucking gigantic, If I understand the scale correctly then it's larger than a whole sector

[NecronLord]

http://www.joachim-adomeit.de/wh40k/spacemap/map.html

That map looks like they've flipped the canonical one upside down, twirled it around, and randomised the labels. Naogeddon is nowhere near there. And the Gothic sector's out in the middle of nowhere...

[18-Till-I-Die]

Yeah i know space is three-dimensional, by the way the map is situated i assume we're to take this to mean their in 3D. Interestingly: the way it looks, is like the Cadian Gate is a literal corridor through this spherical cloud, and other ways in and out are obscured by the warp storm.

It also points out several Craftworlds besides those traditionally shown, and gives statistical data on various worlds and sectors that may be of use. Its one of the most accurate 40k starmaps i could find.

[18-Till-I-Die]

http://www.joachim-adomeit.de/wh40k/spacemap/map.html

That map looks like they've flipped the canonical one upside down, twirled it around, and randomised the labels. Naogeddon is nowhere near there. And the Gothic sector's out in the middle of nowhere...

Really? I didnt know there was a canical map, i've been looking around and all i could find was this one and a a few pictures from other ones in less detail.

Edit: that should probably read "most detailed" map i've seen.

[NecronLord]

Its one of the most accurate 40k starmaps i could find.

It's about as accurate as a map of the USA fingerpainted by a five year old.

[NecronLord]

Really? I didnt know there was a canical map,

It's got a damned two page spread in the 40K rulebook. Can't miss it.

[18-Till-I-Die]

Really? I didnt know there was a canical map,

It's got a damned two page spread in the 40K rulebook. Can't miss it.

I didnt know there was an official one, i've seen other maps so my mistake. Anyway, sorry bout that, but it may be of some use.

[Lost Soal]

Imperium (Adeptus Mechanicus)

False Gods, Pg 18.

The Imperator-Class titan represented the pinnacle of the Mechannicum's skill and knowledge, the culmination of millenia of war and military technology. The titan had no purpose other than to destroy, and had been designed with all the natural affinity for the business of killing that mankind possessed. Like some colossal armoured giant of steel, the titan stood forty-three metres tall on crenellated bastion legs, each one capable of mounting a full company of soldiers and there associated supporting troops.

According to this, an Imperator-class Titan stands 43m tall.

A quote abouts its weapons

False Gods, pg 19

Giant, rumbling cranes suspended from the ceiling lifted massive hoppers of shells and long, snub-nosed missles into the launch bays of the Titan's weapons mount. Each gun was the size of a hab-block, massive rotary cannons, long range howitzers and a monstrous plasma cannon with the power to level cities.

General Technology: Industry & Scope of Operations:

Fleet Numbers of the Merchant Navy.

From Fabrick of the Imperium

It is a given fact that through the might and valour of the Imperial Navy, the raging tides of foul aliens and vile heretics that infest the galaxy have been stayed from overrunning the millions of worlds that over the millennia have come under the Emperors beneficient rule. While these hulking, powerful warships are the most visible representation of Mankind's command of the stars, it is actually through the millions of humble merchant freighters, lumbering heavy transports and sleek fast clippers that make up the vast majority of Mankind's interstellar spacecraft by which its vast domain is held together.

The merchant Navy is millions of ships strong, outnumbering the Imperial Navy by at least 2 to 1, probably more.

Its also implied that there are multiple million worlds within the Imperium.

[Elheru Aran]

Someone may want to link that thread Azazal did on Titans... it was pretty comprehensive, IIRC.

[white_rabbit]

According to this, an Imperator-class Titan stands 43m tall.

I officially give the fuck up.

[Azazal]

According to this, an Imperator-class Titan stands 43m tall.

I officially give the fuck up.

Hopefully it's a typo?? I mean come on GW, right in Horus Rising you state an Imperator as standing 140 meters.



AHHHHHHHHHHH!!!!!!!!!!!!

[NecronLord]

I officially give the fuck up.

The Titans bit is going to be... long.