WH40K - 40K misc numbers... (SDN)

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WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Sun Oct 11, 2009 12:43 am

40K misc numbers and analysis thread
Oh boy. This one is huge. Ten pages, and probably a lot of claims to contest. it has paragraphs about Battlefleet Gothic, which I'm sure would be of particular interest to people looking for more data about spacebattles.








Connor MacLeod wrote: Yes folks, I'm starting another little thread/essay in a long seres. This one will be for all the misc stuff I've uncovered but never knew where the fuck to put it. Alot of it will be mainly fluff from the RPG sources, but it will also be in some cases wher enovels are used.

I plan to cover (so far)

- Misc technical tidbits of capbilities from The Imperium, specifically the Guard (vehicle capabilities, informational capabilities, etc.)

- misc weapons data (lasgun scopes, lasgun types, etc.)

- misc capability calcs (bolters mainly, but this wo't be a calc so much as"I saw it on mythbusters" referenes.)

- Warp speeds (highly variable)

- armour types/construction/possible qualiteis

- Vehicle and equipment data

- "projectile" weapon capital ship calcs. This will encompass mainly bombardment cannon, ,nova cannon, and macrocannon/railguns.

- various and sundry "lay waste to city/contient" bits from BFG

- Torpedo and warhead/ordnance calcs. Again mostly odler stuff, but still interesting.

- Whatever the hell I feel like adding.

Compared to the other essays/thread sI've done, this one will probably be alot less on paragraphs of numbers and analysis and more like my novel analysis threads (bits and pieces quoted here and there.) It probably will also be more jumbled and less coherent, but I'll try to kepe that to a minimum.
For the moment (and because I'm lazY) I'm just going to put up warp speed calcs. Because I have that most conveniently sitting around and reasonably well organized. There are other calcs elsewhere of course, and knowing me I'll find many others, but what the hell.
You'll have to remember that regardless of trip duration, accuracy of arrival is actually not assured.
From "Execution Hour":
"Position confirmed as the Dolorosa system. Estimate we are within 89.7% accuracy of intended exit point." Semper made a note to commend his navigator. Any jump that hit its intended exit point with more than a 70% level of accuracy weas considered the mark of a master.
The rest of the quotes are properly analyzed by Connor. All in all, warp has a random factor that can push, in its best condition, warp speeds to high tens of thousands of c, perhaps a couple hundred of thousands of c with exceptionally good currents, but generally in the lower range, in the low tens of thousands to mere thousands of c, with an astropath.
Without one, jumps are much smaller and slower. And probably risky.

I'm moving out of the warp travel section then, since it appears free of spectacular and improbable interpretations.

In my opinion, this is solely due to their certainty that once a fleet arrives, it wins, simply and purely, because of the assumed insane firepower.

Rogue Trader:
Storms are constantly forming and dying down, at any time at least 10% of the galaxy's solar systems will be inacessible beacuse of storms. Half of these systems are cut of ffor less than a year, but many remain isolated for many years or even centuries. Indeed, some systems have always been isolated, and show no sign of becoming otherwise.
Still, coupling the inaccuracy of jumps (with an astropath btw), to the varying speeds, with storms blocking at least 10% of the star systems, forming haphazardly, half of them lasting less than a year and others for years or even centuries, planning a strategy and guaranteeing the certain arrival of a fleet either in time, or at all, is simply impossible.

...

The thread gets a bit boring, so I skim it and get to the firepower calcs for warships.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Sun Oct 11, 2009 1:01 am

That means beaming up to page 3, and following with page 4 and 5.







Connor MacLeod wrote: (BFG rulebook)
Page 8
"They [battleships] can absorb tremendous amount of damage and mount weapons batteries capable of laying waste to entire continents.
This implies firepower on the order of tens or hundreds of teratons minimum (for weapons batteries.), though it depends heavily on the size of the continent and what "laying waste" means. Vaporizing a continent, ,for example, could go well up into the e10-e11 range (like with the Eclipse superlaser.) It can be taken to mean "teraton/petaton" range in any case.

Timeframe is also not specified, but in context it would seem to refer to a "single shot" capability, since any weapon in theory could achieve those results given enough time. (also earlier sources like Space fleet use a "per shot" context in describing the capability of the Emperor-class Battleship's weapons, so one could reason it carries over.) Or at worst, a short period of time (far less than exterminatus, in any case)
Aside from the error in the orders of magnitude, I know that taking Connor's words at face value is not acceptable. A pity he doesn't present the evidence in question.
Battleships are the meanest ships of all. They're followed by a wide variety of cruisers, some having better firepower but worse ranges, and then escort ships.







Note: As I was completing several comments from Connor's quotations, I noticed that the information he provided may have been incomplete.
So I return at this point with a quotation provided by Dominus, which clarifies some shadowy elements left by Connor incomplete sourcing:
DIRECT FIRING: LANCES

Lances are incredibly high-powered energy
weapons that are capable of burning straight
through an armoured hull or cutting an escort ship
in two. On Imperial and Chaos ships, lances are
usually mounted in huge turrets with quad or
triple energy projectors that focus into a
concentrated beam of destruction.

DIRECT FIRING:
WEAPONS BATTERIES

Weapons batteries form the main armament for
most warships, ensuring that much of their hull is
pock-marked by gun ports and weapon housings.
Each battery consists of rank upon rank of
weapons: plasma projectors, laser cannons, missile
launchers, rail guns, fusion beamers and graviton
pulsars. Weapons batteries fire by salvoes, using a
co-ordinated pattern of shots to catch the target in
the middle of a maelstrom of destruction.

NOVA CANNON

A nova cannon is a huge weapon, normally
mounted in the prow of a ship so that the recoil it
generates can be compensated for by the vessel’s
engines. It fires a projectile at incredible velocity,
using graviometric impellers to accelerate it to
close to light speed. The projectile implodes at a
preset distance after firing, unleashing a force
more potent than a dozen plasma bombs.

TORPEDOES

The term ‘torpedo’ has always been used to
describe any long-range missile carried by a
spaceship. A typical anti-ship torpedo is over 200
feet long and powered by a plasma reactor, which
also acts as a sizeable portion of its warhead,
turning it into a devastating plasma bomb. The
area of a ship given over to the torpedo tubes is a
massive space criss-crossed by lifts, hoists and
gantry cranes for moving the huge missiles from
the armoured magazine silos where they are
stored to the launch tubes.

Once a torpedo is launched, the plasma drive
propels the torpedo forward at high speed, whilst
beginning an energy build-up which will
culminate in its detonation. Torpedoes have a
limited ability to detect a target and will alter
course to intercept if they pass within a few
thousand kilometres of a vessel.
Notice that I'm not aware of the edition in question, and it's not sure to be the same as the one Connor uses. The quotation above, for example, makes no mention of any range for direct fire weapons, contrary to the one Connor brought from page 18 of his rulebook.

Let's note that lances are worth their own paragraph, and as being high-powered weapons (no such mention is made for other weapons), could be the prime weapons of warships. Fits with "Caves of Ice", since Cain only thought about lances destroying the Necrons.
That said, the other weapons would be ought not to trail too far behind in terms of firepower. Perhaps the total density of fire they can deliver per salvo would compensate for the lower firepower of each weapon system, and bring it close to lances.

There has been mentions of torpedoes being 30 and 100 meters long, while the rulebook says the typical one is 60 meters long.
The torpedo actually is a plasma bomb, with a solid shell. It's a long range rocket weapon.








Connor MacLeod wrote: Page 18
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.
Description of the "direct fire" weaponry. note "weapons batteries", which include railguns and missiles as well as fusion beamers, graviton pulsars, lasers and plasma projectors.")
minimum velocity is established as "tens of thousands of kilometers" (or nearly .1c) though its probably MUCH faster for most wepaons (lasers certainly, and probably plasma/particle beams, sincee plasma diffuses very quickly unless it moves at near-c. unless it is some sort of physical projectile.)
Oh, of course lasers will hit, and not almost immediately, but immediately. Period.
However, if we were to take the text literally, we'd have to believe this is not the case.
If we should interpret almost immediately as "strictly instantly", then I suppose that almost immediately could also be few seconds on the other side of the spectrum.
If one is allowed to change the meaning of words one way, why not the other way round, eh?

Puzzlingly enough, Connor's quotation makes no reference to other types of weapons.






Connor MacLeod wrote: Page 20
Weapons batteries form the main armament of most warships, ensuring that much of their hull is pock-marked by gun ports and weapon housings. Each battery consists of rank upon rank of weapons: plasma projectors, laser cannons, missile launchers, rail guns, fusion beamers and graviton pulsers. Weapons batteries fire by salvos, using a co-ordinated pattern of shots to catch the target in the iddle of a malestrom of destruction.
1. Weapons batteries seem to be the "medium/intermediate/secondary" guns on the ship. Smaller but more numerous than the massive dorsal turrets (like lancecs, but not alwayhs lances) they possess less range and power individually but possess alot of punch collectively.

2. Another detail worth noticing is that weapons battereis are perhaps the most diverse weapons around. However, not all ships will carry all those weapons at once. Some ships seem to carry only a couple of those, or maybe only one type (all lasers, or maybe lasers and plasma, or plasma and railgun/macro cannon, or lasers and missiles, etc.)

3. Third: given that weapons batteries are "direct fire" and "instantly hit" over "tens of thosuands of kilometers", and that such weapons include missiles and railguns, the minimum velocity of said missiles is at least 10%c. Railguns are at least as fast, and probably several times faster. (Same with macro-cannon, unless they're guided munitions.) If/when I get around to doing calcs for weapons, this will be highly relevant once some projectile masses are established.

4. Lastly, the need to coordinate weapons of different types and velocities, especially in large numbers (and coupled with their "medium" calibre relative to the big turret weapons) also means that their destructive capability at longer ranges is also more limited (fewer direct hits, or fewer concentrated hits.)
1. "medium/intermediate/secondary" guns on the ship... so I understand that they can be interception and point defense systems. In "Execution Hour", the anti-capital-ship missiles coming at the Bellerophon approached at tens of kilometers per second, not tens of thousands.
I really doubt that the tens of thousands then applies to all weapon systems. We already know it doesn't anyway, since these weapon systems including light weapons, with photons travelling at c.
Also, it's possible that *some* torpedoes *might* achieve impact velocities around tens of thousands of kilometers, but since long range firing, across a system, of projectiles filled with fuel and sometimes being up to 100 meters long is a reality, there's no surprise that this could occur. However, only over multi-AU distances.

2. This would be hinted at by a novel like "Caves of Ice", but the reasoning has limits. Cain thought about a flotilla of ships, and I doubt that all of them would be of the same tonnage and have just one main type of weapon, when you have so many at your disposal, especially since there was no guarantee about the kind of ships that would arrive.

3. The only weapons defined as direct fire are lasers, fusion beams and plasma launchers, from the text he quotes. Railguns are left out, and missiles are not guaranteed to be part of the described group.
Actually, if you properly read both lists provided by CML, here's what we see:

"lasers, fusion beams, and plasma launchers"

and,

"plasma projectors, laser cannons, missile launchers, rail guns, fusion beamers and graviton pulsers"

What we can conlude is that plasma projectors and plasma launchers are the same thing. Same for fusion beams and fusion beamers.
Rail guns are direct hit weapons, but apparently would not fit in the category of weapons firing projectiles at tens of thousands of kilometers, otherwise they'd have been present in the first list.
Graviton pulsers, I don't know. Perhaps tractor beams. Probably rare, short ranged and with an area effect, although Dominus' quote lobs the graviton guns into direct hit weapons.
The last ones, missile launchers, are only in the second list, the one that makes no mention of all weapons being direct fire and having ejected matter travelling at tens of thousands of km.
Thus far, the only missile weapon that appears to hit near instantly is the Nova cannon, which basically is a super plasma bomb.
Note that the mechanics of the Nova cannon imply rules which are completely ignored by those who solely focus on kinetic energy, forgetting about the momentum and the spherical area effect, conveniently or not.

4. Why at longer ranges? At best, the fastest weapons were near instant hits (when they hit), not certain hits. There's quite a difference here.






Connor MacLeod wrote: Page 21
the forty men pulled harder at the traversing chains, heaving the massive barrel of the macro-cannon into position amidst the clank-clank-clank of rusty gears.

....

When it was open, the others bent their backs to the loading winch, ,lowering the shell, which weighed several tons, into the heart of the cannon.
Capital ship "macro cannon", with a shell that weighs "several tons." Going with the "lower limit" velocity I established before of 20,000 km/s for "direct fire" weapons. At that mass/velocity, the KE of the projectile would be 4e17 joules, or just under 100 megatons. Assuming the 40,000 km/s velocity I conjectured, it goes up to ~400 megatons. This is definitely a lower limit. The mass can probably be MUCH higher (and is, ,given other sources. In Nightbringer they're hurling building-sized projectiles out to 300,000 km, and in Iron Hands they hurl shells "three times the size of a man." Both would mass FAR more than "several tons.")

If we assume "tens of thousands of km/s" refers to 100,000 km/s, and apply the same logic (railguns travelling faster than missiles.) and assume a 10 ton shell, the KE is 3e20, or around 70-80 gigatons of KE. Macro cannons, IIRC typically fire explosive warheadS (like bombardment cannons and nova cannon) so they may not rely on pure KE/momentum as the primary/only damage component. In this respect, lower KE/momentum probably would be a benefit, though it probably has a shorter range. Railguns probably are more "KE/momentum" weapons.

Note that given the "mass" of the shell, unless "several" means alot more than 2-3 tonnes, the weapon in question is far too light to be a reasonable anti-capship weapon. In "First and Only" and "Necropolis" the higher-end ground based macro cannons were flinging "multi ton" shells, and those are at best going to be titan grade in comparison.

I'd say it might be a point defense weapon, but the rate of fire would be slow, unless its designed to fire those proximity-detonation shells or something. Then again, this IS 40K, so it may be
some ships DO use point defense weapons like that.
The description clearly poses limits to how long the macro-cannon can be.
It also puts a limit to how big and heavy it can be as well, if you look at the cumulated strenght of 40 men.
And that's without considering how the cannon is not merely hauled, but actually heaved.
In a system with pulleys, unless there were a counter-weight of some sort, one could think that the cannon couldn't weigh more than the total weight of 40 (bulky men). Pick 100 kg "a piece", you get 4 tonnes in total.
If they simply lift the cannon off the ground, pushing against the floor, then they can lift greater masses, but not by that much.
Unless they were all olympic athletes using very specialized gear that would allow for hard snatch moves in unisson, followed by clean and jerk moves in unisson as well (this second one, above the head, allowing for greater lifts, but I don't really see how the crews would come to a point where they'd even be able to complete that move flawlessly --and what a choregraphy!), all you could expect would be a basic lift achieved by men bending over, and human body being what it is, the human body would NOT be able to achieve the lifting of considerable masses that way, especially repeatedly. Without the snatch technique, a human could only lift a moderate fraction of his own weight.

Then the fact that the men pulled chains to heave the cannon pretty much proves that at some point, the cannon would be off the ground, and the only thing maintaining it up that way would be the 40 people pulling on the chains.
So expect a 3-4 tonnes cannon, which of course is silly.
Another possibility would be that the cannon was located below the men, so the chains they pulled were used to raise the cannon from some kind of pit. Perhaps this would allow for a few extra tonnes for the cannon.

Now, if there's some better semi-automated machinery allowing for the cannon to be moved around, fine, but then why need 40 mens to sweat like porks? What? Among those troutatons of energy generated per second, the Adeptus Flegmatus were terribly short of a couple joules in order to allow robotic arms to do the heaving?
What a ridiculous idea, and an equally ridiculous design.

Also, you'd expect a "macro-cannon" that fires hundreds of megatons at the very least, to actually be heavily embedded in a network of cooling systems, huge recoil dampeners and so on, all that stuff being hard to access, instead of being "easily" moved around like all the guys had to do was to place the cannon on some bench.
Like pointed out in another thread, we can also appreciate how primitive the system is, after all. One can imagine the ensuing problems if artificial gravity is lost in that section of the ship.

As for the shell, if there's around as many men charging it into the cannon, you're certainly looking at a shell that well below ten tonnes if there's nothing to help them haul it, and possibly quite more if the shell only needs to be pushed up a rail while gears take care of reducing the efforts.

Everyone would also understand that the Nightbringer shell is one of a kind, totally different. Building sized, we may be looking at something similar, in size, to one of those 30-60-100 meters long torpedoes.

The projectile from "Iron Hands" is three times the size of a man. If you multiplied all dimensions accordingly, and using slightly greater dimensions for bulky figures, you have a width of 1'8" x 3, or 1.5 m, and a height of 6' x 3, or 5.5 m. We assume a cylinder here, so we won't bother with a man's front-to-back chest thickness.
That's a volume of 9.7193 m³.
Now, if we consider the other meaning of size, as volume, then the shell would be three times a human's volume, 0.35997 m³x 3, or 1.07991 m³. A material like depleted uranium would give projectiles between 200 and 20 tonnes, depending on your treatment on size.

Besides, a shell is not a solid monolithic piece of material. It's an artillery projectile that contains an explosive charge.
This has implications on both its total mass and its capacity to handle accelerations.

As for the figures, since nothing seems to put the railguns' muzzle velocities into the tens of thousands km range, it seems that Connor's figures are meaningless.






Connor MacLeod wrote: Page 22
A Nova cannon is a huge weapon, normally mounted in the prow of a ship so that the recoil it generates can be compensated for by the vessel's engines. It fires a proejctile at incredible velocity, using graviometric impellers to accelerate it to close to light speed. The projectile implodes at a preset distance after firing, unleashing a force more potent than a dozen plasma bombs.
I would generally assume "close to light-speed" to mean at least 80-90% of C. The size of a Nova cannon shell is never given precisely, but the diameter of the shell is given in other sources (50 meters in Warriors of Ultramar, though a 30 meter diameter nova cannon is mentioned. Mass can be derived by assuming the length is at least equal to the diameter, or (more probably) a multiple of the diameter (2-3x longer than the diameter, for example. A 50 meter diameter shell would be 100-150 meters long.)

Example: Going by a 50x150 meter shell made of iron (assume 30% solid, its supposed to be packed with explosive o funknown type and density) fired at ~90%of c yields a shell mass of around 770,000 tons and and a KE of 9e25 joules, putting Nova cannons well into the petaton range (~21 petatons roughly here.) In the literature, Nova Cannons are implied to "charge up" for firing just after loading, implying that the gun is charged in a matter of seconds at most.

It is also interesting to note that the recoil generated needs to be compensated for by the engines. This suggests that the recoil/output of the Nova cannon is of comparable magnitude to the output/thrust of the engines. And if you know the specifics of one, you can probably estimate the other (IE figure acceleration from ship mass and the recoil of a Nova cannon.) Taking the shell example above, the momentum would be 4.77e17 kg*m/s. If the ship in question has a 5000 gee acceleration rate the ship itself masses somethign like 9.5 billion tons. A mass far greater than implied by a number of other sources, but I tend to believe 40K ship masses are dramatically under-stated in the vast majority of cases. Given the estimated accelerations from other sources like Sabbat Martyr or Grey Knights, and estimate the mass from starship dimensions, the output of engines for a cruiser/battlecruiser grade would be high TT/low petaton range easily (consistent with the "stellar scale" outputs mentioned in Execution Hour for warp engines, which aren't as energy intensive as the realspace engines as per Ravenor which does confirm the estimates.

The explosion of a Nova cannon shell ought to be at least comparable in magnitude ot the energy expended in getting the projectile to the target(s), which suggests its petaton range, if not significantly higher. Note that if this is the case, the energy density of the explosive, like plasma reactors, must be many many times greater than conventional nuclear fusion or even antimatter, for it to be equal to or greater than what a near-c projectile provides. Then again, 40K is not a stranger to "power sources with insanely high energy densities." either.

Note that "plasma bombs" is another term used in earlier sources for torpedoes, so this might imply that a Nova cannon is equivalent to a dozen torpedoes (a double salvo, in other words.) I do find it odd they say "force", as this implies that a Nova bomb detonation has some sort of blast/pressure effects like a conventional explosive (nuclear/antimatter warheads would not have blast effects, ,becuase the blast is a result of atmospheric detonations.) which may hint at some sort of exotic mechanism, perhaps like a seismic charge (or maybe a multi-function warhead). anyhow, this would imply plasma torpedoes are in the teraton range or so (double or triple) assuming a multi-petaton nova cannon.

One thing that bothers me about Nova cannon - why do they mount only a single cannon? Given the size/diameters of the weapon, and that virtually every other 40K weapon is usually a multiple mount (torpedoes, lances, and weapons batteries are all aggregates of multiple weapons.) but why not nova cannon? It would make a bit more sense to fire at least several shells (imrpove chances of hitting and coverage, ,for one thing, as well as giving the ability to engage multiple targets.) And it owuld make interception harder. (though the combined mass/velocity of the shell may already assure that.) Also, why not make it guided? They can make guided shotgun shells, bolter rounds, autogun rounds, guided tank and artillery shells. Hell weapons battery cannons and bombardment cannon are implied to use some sort of targeted/guided shell... but why not Nova cannon?
I won't do more here than refer my own take on "Shadow Point", and merely notice that Connor doesn't seem that puzzled by the inherent logical flaw of an area effect explosive weapon that travels near c (in the book, the nova cannon's bizarre projectile exploded amidst the Ork formation, close to Roks), and probably liberates plasma with a certain "force".
The BFG rulebook speaks of a spherical area effect. Try to get that with an explosive that travels at near c.
You will fail, no matter how hard you try, since you need to get rid of momentum first.

What is interesting here is that it's given a yield of more than a dozen plasma bombs. Perhaps 13 or 14 of them.
Now if you remember the 1st&2nd editions thread, here's how plasma bombs were described:
Page 98 wrote: A plasma bomb is a large missile typically used by or against spacecraft. They are also used for planetary sieges. The missile energises at launch, converting into a mass of seething plasma - each missile becomes a ball of boiling energy sufficient to melt a city-block. As it converts to plasma, the missile divides into 6 fragments, this enables the plasma to spread out and saturate its target. A target under plasma attack becomes a blazing inferno which only the very fortunate survive.

Range is practically unlimited. A plasma bomb can be fitted with drives enabling it to be launched from the edges of a solar system agianst a target on a distant planet. A powered missile of this kind is sometimes known as a plasma torpedo, or plasma lance.
So remember what I said. As it divides itself into 6 warheads, it can more effectively spread its destruction. It also melts a city-block, not level or vaporizes, which again raises issues concerning the mechanism at hand, and could point at some kind of heavy melta-like weapon.
An information, obviously, that's far more detailed than the vague "energy of a small star" hyperbole from "Last Chancers: 13th Legion" for example (p. 133-134).

All in all, it severely limits the explosive power of the Nova projectile.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Tue Oct 13, 2009 8:29 pm

Connor MacLeod wrote: page 23
The weapons carried by some ships are powerful enough to reduce whole cities to plains of radioactive glass. Ships are armored and shielded in order to resist their savage caress,, hulls are heavily reinforced so that they can survive the horrific pounding of gigawatts of energy.
We actually hear about ships destroying cities in various forms (vaporizing, melting, ,etc.) quite often. Battleships, cruisers (or rather specific weapons on crusiers) and even frigates have been mentioned as capable of destroying cities with their weapons.

Cities can be quite lage too. Either fortress cities (like we see in 13th Legion and Ghostmaker) to Hive Cities (which span many tens or hundreds of kilometers in diameter minimum, and extend many kilometers both above and even under the ground). Hell, some planets have continent sized buildings (like Terra, but also some Hive Cities and Forge worlds do ). Destroying cities of that scale requires immense firepower.

Calculating it can be hard, given the variables involved, though"reducing cities to glasS" implies melting. Assuming a 10 km diameter city, composed of iron, 90% empty and with an average building height of 300 meters (with a fairly crowded density), it would take at least 5 gigatons or so to melt. Something larger (say 50 km in diameter, or about hive city size) that extends up ~ 5 km in height, as a cone, composed of iron and 90% empty) would take around 738 gigatons to melt. THat doesn't include anythign below ground - assuming a 200 meter depth into the rock, 90% empty, would be several times greater) would add around another 40-80 gigatons depending on composiition.

The "gigawatts of energy" is almost certainly an error, since its a ridicuously low-end output for 40K ship weapons (given that Exteminatus even at its absolute lowest for cruisers is double/triple digit GT/sec and a man portable meltagun is gigawatt range.) and energy is not measured in "watts". I'd take this to mean that 40K ships are meant to withstand "gigatons" of energy, which would be more consistent. (especialyl given the nature for macro cannon shells and torpedoes to ignore shields and penetrate before detonating - they're definitely gigaton range.)
Of course gigawatt is ridiculous, but it makes you wonder if the author had any idea of the figures he threw around.

Then, should we put much stock into the idea that warships have enough firepower to reduce a city to radioactive molten slag?
Are we ready to adopt an unique standard and interpret similar references from other franchises in the same manner?

Rather unsurprisingly, Connor goes picking the biggest possible cities, and ignores the timeframe.









Connor MacLeod wrote: PAge 43
Ships coming out of the warp must appear some distance away in deep space or risk destruction among the graviton surges in-system. Many civilised worlds have specific jump points marked by beacons to assist navigation.
Gravity is speficied here as the primary reason that prevents ships from dropping from the warp in-system. Earlier sources give specific explanations (which will be covered as they come up), but we can draw certain conclusions form this fact:

First, a sufficiently strong gravity well will interfere with the transition to warp.Gravity is not strong enough to hpysically "harm" the ship, so the danger must be in gravity fouling up the warp transition in some manner (and the forces/energies in the transition destroying the ship itself.) It is implied though that a ship COULD emerge in-system from the warp unharmed, but that it's gambling the ship's destruction.

Second, while the vast majortiy of sources suggest that a ship must arrive "out system", this source implies that the ship must only appear "some distance away". Given the inconsistent distances given in some sources (tens of millions of miles in Eye of Terror as opposed to billions of km in Chaos Child, for example), ,its possible the "Warp limit" is not always a fixed quantity, and may vary according to the system (how strong of gravity wells it has, number and type of planets, etc.) and other factors (orbits and whatnot.) Perhaps, for example, "gaps" in gravity may appear where emergencee from the warp in-system is possible. But since detection of realspace from the warp (and vicee versa, save by psychic ability) is not possible in 40K, it would be virtually impossible to detect such without some sort of assistance or planning.

We do know that a number of smaller "warp-capable" devices (displacement devicecs like the dispalcement shields or Eldar Warp Spider packs.) as well as weapons (Warp missiles and vortex grenades/warheads.) as wlel as the Eldar Webway can work within a gravity well, so emergence within a gravity well should be possible. (perhaps they have to counteract the gravitational field.)
Ships destroyed by graviton surges? Beacons?

As Connor assumes, the idea that a strong gravity field messes up with the warp window is a good idea, however there's no indication that what destroys the ship is the energy of the warp, not the ship's own engine suffering from the funky physics effects.

The BFG book clearly establishes that ships must enter a system from its fringe, otherwise they're at great risks. It's possible that small systems, and perhaps crafts carrying no crew, can take the risk of being exposed to whatever a warp drive does to said craft, and it's equally likely that the mass of the craft is very important.
This pretty much excludes sudden bombardement of a planet after dropping out of warp: ships have to get inside the system, and that could take many dozens of minutes to hours before getting there.

You can always that problem to the lists of issues regarding warp travel for Imperial warships, and their relevance to strategies.








Connor MacLeod wrote: Page 46
Most planets have many small moons around them and most of these are no larger than generously sized asteroids. These rules are confined to dealign with larger moons several thousand kilometres in diameter.
The size of "moons" in Battlefleet gothic. note that this tends to confirm to the "close range" idea established before.
This may also be interpreted as to mean "moons" in BFG are by definition "several thousand kilometers", though that is admittedly stretching things.
Close range is "a few thousands of kilometres."
Amusingly, illustrations displaying ships engaging some targets, often feature spitting ranges.








I'll wedge a quotation of Lost Soal in this stream of text. This one seems to have nothing to do with BFG:
Lost Soal wrote: The 3rd Edition rulebook contains a description of an IoM Plasma Ioniser and this seems the right thread to post it.

Pg 282
90/110 Peta-Watt Open Core Plasma Ioniser
The 90/110 Peta-Watt Open Core Plasma Ioniser remains the most effective power generator in terms of pure energy output since its re-introduction by Magos Technis Voltar. Using time-honoured Coolant-infusion systems, this plasma reactor is capable of sustained use for 1.9x1056 hours before core compression factors exceed tolerable values. Exo-thermic residues equate to one part in five thousand, requireing isolation to be stabilised at roughly 1/126 spin ratio. With the open core plasma ioniser, an omophagic system vents ionised particulate matter through an electromagnetic shielded sub-chamber which in turn refines the plasma and allows it to be reinvested back into the main core. The plasma ioniser requires roughly fifteen thousand man-seconds maintenance/cycle.
Firstly, the power rating. This rating is actually in the right ball-park for the outputs calculated in this and other threads, probably a very fortunate accident on the writers part.
Its sustained use however, causes some problems. It can't mean the standard value of 1.9e56 hours, since thats basically infinite, similarly a actual multiplication would give a sustained use of just under 12 weeks which seems an obsurdly small time frame.
It appears to operate using a similar principle to a CHP cycle, sending waste particulate matter back into the generator. Our own CHP cycles generate efficiencies of upto 90% which may be an indication of this reactor as well.
Maintenance is 4.17 hours per cycle, how ever long a cycle is. Day, Week, Month or Year?
Apparently, according to this source, the excerpt may actually come from the second edition.
Pff, dunno. A guy here provides an equally detailed quotes (with the same "1056" writing, and calls the info bits "excepts", so I wouldn't put the "1056" past pas a typo), and says it's from the 3rd edition, 1999. Possibly same poster under a different nickname.

110 petawatts would turn out to be an output of 26.3 MT/s, perhaps peak.
If it's 1.9 e56 hours... the reactor would be much older than the universe itself (14 billion years by theory) by dozens of orders of magnitude.

If we're dealing with a typo... I don't know, but assuming it's 1.9 x 1056, that's 2006.4 hours. That is, a couple of months, and that makes far more sense (8766 hours per year).

It's not like the third edition doesn't contain its own priceless quantity of gibberish claims, such as "molten gas" (?) or fusion cores that "melt-down" (??), and on the same hand, plasma weapons are said to use hydrogen as fuel for the fusion-produced plasma bolt, a similar technology that's used in plasma reactors (be they fission or fusion based, logically) and drives.
Lasguns vaporize the surface of the target in a small explosion (instead of going through) and melta-gun use "pyrum-petrol gases" with all sorts of weird sub-molecular stuff and molecular breakdowns. If it wasn't already clear that these weapons are definitely weird. Powerful, but weird.

90/110 is also 0.818, so it could be a 818 terawatt core.
Also, the 90/110 peta-watt part could refer to the mechanism that kickstarts the power plant. Currently, science can produces low peta-watt lasers, planned for near-future laser fusion and high density plasma. But these systems only involve kilojoules of energy at best.

That said, a scientist would write it down 9/11, so the terawatt interpretation is not that solid.
The power figure may also relate to the system that is used to kickstart the plasma reactor, notably if it uses some form of beam, not its output.




Connor MacLeod wrote:
Lost Soal wrote: Firstly, the power rating. This rating is actually in the right ball-park for the outputs calculated in this and other threads, probably a very fortunate accident on the writers part.
It would probably be on par with a titan-grade constrcut, or a fighter/shuttle type of vehicle. Then again it might be a powerplant for some city ro whatnot.
Its sustained use however, causes some problems. It can't mean the standard value of 1.9e56 hours, since thats basically infinite, similarly a actual multiplication would give a sustained use of just under 12 weeks which seems an obsurdly small time frame.
Why not? Plasma reactors have already had (From various sources) some very weird properties alluded to them. They have "energy densities" beyond 100% matter/antimatter annihilation - they can run on very little/no fuel. They seem to be tied inot the warp somehow (at least going off the novel "Chaos Child" and certain others.) 40K ships have insane accelerations which are not possible if the ship were limited by fuel-mass considerations the way SW ships are - at least not without incurring substnatial drops in duration/endurance.

I should note I'm not sure how you consider "12 weeks" at "peta-watt" ranges to be a "small timeframe" -that's roughly 3 months continuous operation, and depending on how its used that's not unreasonable - 12 weeks is long endurance for a fighter or a titan, for example. And in the case of a city... depends on the city and their power usage (Which cannot be constant.) If that were "maximum output" for a city, 12 weeks doesn't seem unusual. Especially since the endurance figure seems to be not based on fuel limitations but on the tolerances of the reactor itself - ie "wear and tear", which again is not unusual in either interpretation (its either very tough, or it wears out like everything else with prolonged use without any dfown time and may need repair/replacing at some point.)
Petawatt reactors for Titans? That would already sound excessive, considering the other facts I dug. But fighters?.... Shuttles???......
Wait, why not buggies and washing machines while we're at it?

Without context, it's hard to know what this core is supposed to power. Rulebooks focused on stuff infantries would deal with. Mentions of spaceships are extremely limited, and bizarrely, at least up to the third edition, mentions of Titans are even rarer.
This plasma core could be powering anything as well, even perhaps a large planetary area and its bucket of defenses. You just don't know, so that supports precisely zlitch.





An interesting thing is that while Connor picks, from page 47, the data about the effect of a star's radiations on sensors, he decided to leave out that rather... annoying piece of fluff:
BFG rulebook, p.47 wrote: SOLAR FLARES
Most stars periodically release explosive bursts of energy over small areas of their surface. Of course, small, in solar terms, means areas hundreds of millions of kilometers across! These huge flares of energy rush outward at tremendous speeds, flooding the vicinity with highly charged particles and magnetic shockwaves. A shielded vessel can find its protection virtually overwhelmed by these events and a vessel without shields is sure to suffer damage.
These are most mundane flares, quite confirmed by the text I cited, and the quotations below.
The follwoing quotations are taken from the section about Battlezones; that is, heliocentric and successive discs dividing a system, each zone bounded by an inferior orbit and a higher orbit. There are six zones, the 6th one being the most distant.
Now let's see where flares occur.
BFG rulebook, p.43 wrote: 1. Flare Region Generator
The flare region is closest to the system's sun. It is an area scoured by incandescent flares of superheated gas from the surface of the sun and fierce radioactive winds. Planets this close to the star are almost always death worlds, places too ravaged by the sun's heat to be habitable to life.

2. Mercurial Zone Generator
At the mercurial zone the sun's ferocity is still awesome to behold, but solar flares less frequently reach out to burn everything in their path. Occasionally, a planet can be found in the mercurial zone which can sustain limited life deep underground or constantly moving around its dark side to shelter from the sun's rays.
The distances are quite vast, and the mercurial zone is in reference to Mercury's orbit and environmental conditions.
Being lazy as well, I merely picked wikipedia to get an idea of a solar flare's energy: 6 e25 joules.
Surely, that's large, but remember that it's spread over an immense region.
Since the fluff puts a flare, on the photosphere, as wide as hundreds of millions of kilometers across (x e5 km), even picking the smallest surface area possible (based on 2 e5 km), this gives us a SA of 1.257 e17 m².

That's an intensity of 4.77 e8 J/m², in the best conditions.

Picking a 1 km long ship, assuming it's a brick that's 350 meters high, assume that it's surrounded by a shield that adds a total of 100 meters in both directions, we get a broadside surface area of 4.95 e5 m².
So the threatening energy level is of 236 e12 joules.
And no exotic sun, by the way.

Likewise, the electromagnetic radiations disrupt inner communication systems and captains avoid this region like a plague. It makes piloting very difficult.

As a sidenote, the ship Invincible had 11 reactors at least.








OK, sailing away from that rather big chunk of firepower quotes...



Connor MacLeod wrote: Big update! I want to dump out all the rest of the BFG stuff cuz I want to move onto other sources.
Page 67
Pott maw is the capital system of the Gothic Sector. The planet itself is the most productive hive world in the region, with a population of over 200 billion people.
Port Maw: type and population given. Note that it implies more than one Hive World in the sector.
200 billion for a most influent and important hive world, capital world of most prestigious sector.
We may expect lower population numbers on other worlds.
Isstvan III (and its hive) lost 12 billion only when its surface got goo-incinerated by some magiviral bomb.
A great many Warhammer 40,000 rulebooks and novels share an introduction which always mentions a population of untold billions, no trillions nor quadrillions.

And let's not be flailed by the "but population density!" argument, no matter if definitions of hive worlds argue for some kilometer high cities or else, because 200 billion is still very short of a planet that's supposedly entirely covered with cities.
In other words, the canon itself says not to expect higher population densities. And remember, Port Maw is no hive world to scoff at. It may even fall close to Terra.
I read that later editions of the rulebook, notably the fifth one at least, speak of quasi-hives, which is necessary, because there are hive worlds, described as planets fully covered with urban areas, which actually have been sporting deserts, jungles, forests, rivers and even oceans.
It could be that only a few worlds are really "full hives".








Connor MacLeod wrote: PAge 85
It [Imperium] is spread over tens of thousands of light years, its armies alone numbering many billions of soldiers.
"billions" of soldiers in the army alone, at a minimum, but this is clearly a minimum.
Fits with billions of people as a whole, since this is a gruesome heavily militarized regime. The army is pretty much one of the few segments of humanity where one may shine and get a slightly better standard of life.
Considering the enemies of man spread across the galaxy, it's also obvious that recruitment would be massive.
The Gothic Sector is fairly industrialized btw. Other sectors, probably not as much, likely with less hive worlds, and thus less population.
Meanwhile, the Space Marines, as a whole, number at 1 million, with a thousand Chapters (or Regiments, or perhaps even Orders) with a thousand men each. There are less SMs than there are worlds in the Imperium.







Connor MacLeod wrote: PAge 97
"The two Blackstones have taken up station five htousand leagues from each other, some seventty-five thousand leagues from Fularis II and just out of range of the weapons platforms, except for the torpedo launchers.
This quote was brought up in the "Grand 40K quantificaiton thread" long ago, so it should be aware to anyone. 1 League is about 5.6 km, so the range given is 420,000 kilometers. This was considered "just out of range" of all the weapons platforms (lance and weapons batteries) save torpedoes (which were in the range still.)
Where were the weapon platforms?
High orbit? Orbiting some moon? Lagrangian points?






Connor MacLeod wrote: Page 97
Other recovered evidence points towards an energy beam being unleashed towards Fularis II. The Vindictive was caught full on ,her shields overloaded instantly and outer hull vaporised as the energy wave passed over the ship. Fularis II was later found with tis atmosphere stripped off and the surface scoured to a rocky plain.
Stripping the atmosphere off of a planet requires around 3e26 joules against an inhabited planet - "scouring the surface" could imply similar magnitude (call it e26-e27 joule range.). It is safe to conclude that the Vindicitve took a fair fraction of that energy, indicating that it's shielding is well into the petaton range (the ship took some damage, but it wasn't severe enough to desroy it entirely.)

We have no idea what vessel the Vindictive is, but its either probably a cruiser or frigate, ,most smaller escorts are usually in squadrons and battleships would be too rare.
This part will (I hope) be addressed in a specific APK thread (Abaddon's Planet Killer).







Connor MacLeod wrote: Page 134
Not only are they (eldar fighters) highly agile and extremely fast (utilising some form of interia-dampening field that enables them to literally turn on the spot.)
Eldar "inertial damping" tech give eldar ships extreme mobility - either because they can compensate for engine accelerations in very very short time frames, or they provide some active propulsive force on their own.
So the IoM's ships can't do that? Without such a good ID tech, how crews are supposed to handle many thousands of gees?
Wouldn't this information actually tell us, squarely, that Imperial ships aren't that agile after all?






Connor MacLeod wrote: BFG Magazine #2

Page 33
A black globe crackled and flared into existence over the spot. Real space rippled visibly and then shuddered back befor ethe groaning warp drives of the Dominus Astra as it hurled itself into the warp. Reality contorted under the strain: Mass and warp energy collided in a cataclysmic implosion of black light and impossible sound. All of the closest Tyranid ships were dragged into the Astra's displacement and were lost with it. Those further away were smashed in the swirling storm of dust, rocks, and other detritus swept into the ship's wake. Great flares of incanderscent gas gouted up from Circe to incinerate the handful of surviving ships that remained in a holocaust of flame.
Malfunctioning warp drive of a battleship acts like vortex warhead. Widespread destruction amongst Tyranid fleet.
Clearly different than the energies pouring through a warp window when a ship exits warp. So remembering the graviton pulse babble from a couple paragraphs up, we see that the failure comes from the warp drive and that could be what destroys ships: a bizarro folding phenomenon.

Also kudos to the IoM for not thinking about exploiting this deus ex machina, no matter the price, especially if used far from inhabited worlds.
Of course, with shipyards taking between years and centuries to build a couple of ships...

That said, since warp drives are "dangerously unpredictable" (2nd or 3rd edition), it could be possible that there would be too much wasted ordnance, and even risks of destroying the warship.
However, when you consider the composition of warheads launched by those same warships, and hit ratios... the risks of self damage, friendly fire and wasted ordnance don't seem that contrasted.
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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Tue Oct 13, 2009 8:30 pm

  • TITAN STUFF


Just another note, since we were talking about Titans.
As they're used as a benchmark for a warship's firepower, it would be good enough to have more info on them.

There. I'll add some stuff here, but this will probably end copied in a more complete thread about Titans, if there ever needs to be one.

First, read this post about some of the most important sources about Titans.
Oh wait, let's get a full quote instead:
Gotthammer wrote: The books are Adeptus Titanicus (1988), which covered Warlord vs Warlord combat in the Heresy (very early heresy fluff). There was the expansion Codex Titanicus (1989 - yes it is official, yes it is that complex), which contained rules for Reavers, Warhounds, Gargants, Phantoms for AT. It also had rules for combining Adeptus Titanicus with Space Marine v1 (1989 - Marine v Marine during the heresy), which was known as 'the Epic Battle System.'

These used unit cards that had points and weapon layouts for titans (though you could build your own very easily with AT or very complicatedly with CT), and for infantry and light vehicles units (had points and morale details).

Then there was Epic v2 (1991 - the Space Marine v2 boxed game), which had expansions such as 'Armies of the Imperium', 'Renegades' and 'Warlords'. This had no stand alone Titan System, and the Titan vs Titan combat was much simpler, not being the focus of the game. Titans had data cards that had target squares, and when fired at you had to roll special dice that could alter what square was hit, and thus what damage was taken.

Titan Legions was released later though (1994), and was a stand alone system, but compatible with Space Marine v2.

After Epic: Space Marine went away it was replaced by Epic 40,000 (1997), which basically killed the Epic system and removed 6mm as a core game :(

Then in 2000/2001 Adeptus Titanicus II was published in White Dwarf (I forget exactly when), which is available to download as a PDF.

Epic: Armageddon apeared around this time as a Specialist Game.


Basically you can play Adeptus Titanicus and Space Marine v1 together, but you need Codex Titanicus and both the core systems' books (and Space Marine's cards).

You can play Space Marine v2 and Titan Legions together without too much trouble.

Epic 40,000 by itself (where it belongs).

Adeptus Titanicus II is also standalone, and in my opinion inferior to Adeptus Titanicus v1.

Epic Armageddon is again different from the rest.


As for finding the cards and whatnot I suggest EBay and be prepared to shell out a lot of money for a complete set.
Plus this source.


I realized I forgot to point to the post which explains why I used the CTO:
Gotthammer wrote: Codex Titanicus isn't a complete ruleset - it has expansions for the Original Adeptus Titanics, and rules for merging it with the game Space Marine. If it's a PDF that says "Codex Titanicus Online" on every page and opens with a story about a new princeps taking over a warlord during the battle of Tallarn, it's legit.

The Codex Titanicus Online team seem to have copied the text and some of the pictures (at lo res) to reduce the file size from what plain scans would be. They also did some editing here and there (changing Horus' command bunker to his command ship for example). It comes out looking fan made, but the contents is accurate.

The PDF from GW (that only has a few Imperials, requires reactor rolls etc) is th eone from 2000ish - that's here: http://www.games-workshop.com/MEDIA_..._Titanicus.pdf

It is technically ATII, though there was a slightly earlier version for use with Epic 40,000, so maybe that's where the confusion is.

Space Marine v2 and Titan Legions have the biggest number of units for all races (excluding Tau and Necron as they weren't around then), but they rely on the unit card system, so getting all the info you need could be a hassle.

Adeptus Titanicus I only contains Warlords, but Codex Titanicus adds Reavers, Warhounds, Phantoms and Gargants. There are more rules in CT, but some of those can easily be ignored as they are replacements (such as new, more comlex, damage tables).
So, in the Codex Titanicus Online doc, there's a small story that retells the battle between five Ork Gargants and their armies, against an Imperium armada of three Warlord Titans (33 meters tall max, really), one Warhound Scout and several other small vehicles and Space Marines.

The unique Warhound is hit by a Gargant's belly gun:

"The Gargant shook, and a huge explosion shrouded the Warhound. Only the stumps of legs remained."

Later on, the Ork leader of the Gargant Stompsmasher orders a shell to be loaded, and fired at a Warlord Titan. The Warlord Titan is caught in an airbust (airbust shell type of ammo, burst circle: 12 cm wide), loses two arms and its carapace takes damage, moving unsteadingly from there.
Then comes "a mighty explosion." "The Warlord had ceased to exist. All that remained was a crater, filled with bubbling plasma." Which kept boiling when the battle was over.

How there could be a bubbling plasma in an open crater is rather weird.
Aside from an interesting theoretical liquid model applied to the Sun, it doesn't make much sense to me.

That is, however, the cumulative effect of a Gargant's shell destroying a Warlord and its entire stock of weapons and high grade fission fuel (remember, the reactor produces plasma).
There is no indication that it leveled the battlefield though.

Interestingly enough, the Belly Gun is described as a huge cannon, bigger than a Macro-Cannon.
Check the proportions of Gargants on the Lexicanum page.

Now, on the effects of a Gargant's Ball.
It is a relatively primitive giant explosive cannonball. One rolls at the feet of a Warlord Titan, then explodes against its hull. It's unknown if the shields were weakened, but they contain the fire for an extremely brief moment, then drop and let the flames reach out.

Here's the excerpt:
C.T.O., p.55 wrote: There was a rumble in the Gargant’s innards, and with a boom
that sent steam bursting from every pipe on the Bridge, the Ball
was blasted through the air towards the Titan. It hit the ground
some hundred meters in front of the machine and thundered along
the ground in a great spray of steaming earth. Too late the
Warlord’s weapons tried to pick off the deadly device. It rolled
against the Titans legs like a faithful pet and exploded. For a brief,
frozen moment the awesome blast was held inside the Void
Shields. and the entire machine was hidden under a dome of
storming fire. And then the generators gave out and the explosion
blew away like a bursting bubble leaving the Titan staggering
backwards, flames belching from every joint. Weapons firing
pathetically into the air, it overbalanced. The other Warlord was
following too close... With painful slowness it tried to sidestep from
under the toppling wreck. Like a drunken friend, the dying
machine teemed to slump over its companion in a clumsy embrace.
Trailing a pall of black smoke they crashed to the ground. A
reactor chamber split apart under the impact. fireballing them
both.
Basically, a Titan's breached reactor is quite a good bomb that's that deadly to a critically close Titan. The second Titan couldn't count on its VSGs for protection then, since its shields extended beyond the first and damaged Warlord.
They both blew up, the second Titan obviously also having its reactor breached by the explosion, and both of them having their ammo also cooked off.
While we don't know if the first Warlord's shields were in good shape or not, the fact that they were there means there's no reason to consider that the Warlord was damaged beforehand.

A Warlord Battle Titan's Void shields extend beyond a radius that's large enough to accept the very close proximity of another Titan. Technically, for a Titan that's more than thirty meters high, this should correspond to a range of 40 to 50 meters, to allow enough wiggling room for close combat moves. Add that to half of a Titan's width, say 15 meters, and you have a radius that's between 55 and 65 meters.
The shield enveloppe is dome shaped. This would provide a low end for the Ball's fireball.
A cursory look at the NWEC reveals that the explosion, although non nuclear, could be around 2 kilotons of TNT.

A lower end would be obtained by looking at the rule "Merging Void Shields", which explains that shields are merged, and thus work as one, when the bases of the Titan models touch each other.
This changes the values dramatically, as the radius of a shield's enveloppe suddenly becomes half the Titan's complete shoulder width, plus a few meters for good measure. Say 20 meters.
The explosive yield would definitely be sub-kilotonish.

If we continue to look at the size of the fireball, we may want to consider how Void shields work first.

The way Void shields work largely appears to be velocity based, plus a given threshold when it comes to heat and light. In the case of an explosion, it's hard to know how much of the already present air would be pushed outside the Void shield. The more air that would be pushed outside, the more the initial fireball could grow without restraint.
The shockwave of high explosives is hypersonic, which means that in all likeliness, considering that the volume inside the Void shield turned to flames and remained contained for a very short fraction of a second, then very little of the air would have time to get out before the shockwave would reach the Void shield's inner surface.
The problem is about how much air can be heated before the shockwave travels through the fireball. In the case of a nuke, the fireball already blossoms within microseconds before a form of shockwave expands, temporarily masks the fireball, and then grows beyond it, revealing the fireball again (the very short "two-flashes" effect).

With chemical explosives, there's quite a bit of difference going on here.

We can rely on a simple estimation first, from Operation Sailor Hat, testing various effects of 500 tonnes of explosives, most likely TNT.
Interestingly enough, the explosives were packed under a dome --heavily pixelated :]-- which luckily, proves to be a similar premise to our Ork Ball ammunition for the Gargant's Belly Gun.
It was 17 feet high and 34 feet wide (10.3 m).
As you can see on this neat video, the fireball was as wide as the nearest ship was long.
Looking at the ships present for the test, the longest one, the USS Atlanta (CL-104), a Cleveland-class light cruiser, was 610 ft long (186 m).
Then there were several other ships 533 and 437 ft long. Respectively 162 and 133 meters.
After further reading, I got confirmation that the nearest ship was the USS Atlanta. So basically, we can consider have a fireball that was 186 meters wide at least. Although it could be considered slightly larger, it would just make the overall Ball's yield lower.

But this methodology is ought to be limited. After all, the fireball is contained. It more or less does present a lower end.
Wong's NWEC tends to provide some of the highest figures, tickling the 1 or perhaps two digits kiloton range, while the Sailor Hat example would tend to point to one if not two orders of magnitude less.
Let's also remember that these numbers are worked out for 33 meters tall Battle Titans. There's still those 40 meters tall Emperors

What about working from the projectile's volume then?

First, the Gargant. If we pick the one from Caves of Ice, it was eighty meters tall.
        • Image
The bore is 2.61 meters side. Assuming the Ball is just that big, its volume would be 9.31 m³.
If 10% of its volume was dedicated to the shell and fuse systems, then the remaining 90% would correspond to a volume of 8.38 m³.

Secondly, the explosives. Some are more blasty than fireballey, but still, going with high explosives, and in particular, octogen (HMX), assuming it would be used pure, we have a density of 1.91 g/cm³ in solid form, for a blast velocity of 9100 m/s.
That's 1910 kg/m³, and thus, the Ball's mass of explosives would be 16 tonnes.

If we attempt to obtain the kinetic energy of the chemical blast, based on 16 tonnes and a speed of 9100 m/s, we get 662.5 e9 J.
Background Art

Explosive materials are classified [blah blah blah]... According to the paper, hexa-nitrohexaazaisowurtzitane (*sigh*) has a density of 1.98, a detonation pressure of 432 Kbar and an energy density of 455 cal/cm³. From this it follows that hexanitrohexaazaisowurtzitane has a density higher by ca. 4 %, a detonation pressure higher by ca. 10 % and an energy density ca. 4.2 times higher than those of HMX (density: 1.90, detonation pressure: 391 Kbar, energy density: 109 cal/cm³), which has been superior in performance to any other conventional explosive materials.
So that's 8.38 e6 cm³ times 109 cal. 9.1342 e8 calories, or 3.827 e9 J.
HMX is insensitive, so I guess it passes the test of shocks. :)

CL-20 is an explosive 14% to 20% more powerful than HMX compositions. Therefore, CL-20 would give a yield around 4 GJ.
That said those values are kinda silly.

Working with calories such as the energy unit generally used for food, we get 3,823.57 e9 J, and around four times this value for the other type of explosive. Just under one kiloton or a couple low kilotons that would obliterate a Warlord-class Titan and obviously saturate the shields with a fraction of that energy as the fireball kept growing once the generators failed.

That, by working from a 80 meters tall Gargant. The other Gargant model also seemed to have a narrower bore for its Belly Gun.
Perhaps the reactants are compressed, which would provide a greater yield, but it's hard to tell.

That projectile clearly crippled the plus thirty meters tall Titan.
It's rather clear that a warship would not need to ditch beyond a couple kilotons per full salvo to get rid of the Titans.

Well, that said, let's continue with the criticism.
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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Thu Oct 15, 2009 5:57 pm

Page 4.
andrewgpaul wrote:
Ford Prefect wrote: As an aside, are there any numbers given in regards to the number of Orks Thraka has commited to the Armageddon campaigns?
From Codex: Armageddon:
"... in excess of 2,000 ships and at least twelve space hulks ..." Is pretty much it.
Well, there's still a thing to notice. I have been reading many typical BFG battle scenarii, and what stroke me is just how small fleets are, up to the point they're just a few ships above what is good enough to call them flotillas.







Page 5.
white_rabbit wrote: The 3rd "battle" was an attack across the entire armageddon sub-sector, Codex Armageddon describes an initial main wave of attacks on over two dozen systems. Based on the warband estimates given in the codex, we have a rather paltry 850k-4.5 million orks in the first wave, approximately 100 Gargant weight warmachines, about 300 Battlefortresses, 20-25% of the warband strength is artillery and armoured vehicles, with about 90k-450k of that main warband number being Artillery or Speedkult warbands, which are almost 100% crews of armoured vehicles and artillery.

Obviously this is only forces attacking armageddon,not the other dozens (at least) of worlds in the sub-sector.

12-16 Spacehulks, 250-400 Kroozers, (as well as the battleships that are indentified later on) 2100 escorts, about a hundred Roks, 3000+ squadrons of fighter bommas (this could be 15k to ??? )

At this point Armageddon is a beacon for all orkish activity in the immediate area, and is drawing orks in probably from across a significant portion of the imperium.

Orks based on Armageddon are also likely to have 10% more muscle mass than the average ork, akin to orks "fighting for tribal leadership" rather than your basic grunt, at the moment, there are estimated to be 30 orks for every human on Armageddon, and without drastic action, its estimated to rise to 50 Orks per human over the next 25 years, and regions "cleared" of active orkish warbands are suffering Orkish population booms, with the orky life cycle of squigs, Snots/Grots, Orks being tripled in speed due to the harsh conditions.

An Ordo Xenos Inquisitor advocating Exterminatus mentions that there were "millions" of orks on Armageddon prior to the second orkish invasion.
For anyone interested in more details about those elements, I'll encourage you to read the thread on your own, especially if you're looking for more numbers.
It gives an idea of the scope of such battles. The troop numbers are high, but the fleet sizes, in general, are not, and the industrial might of the Imperium is extremely limited when it comes to the heavy fleets. Despite Forge Worlds. It's logical that a lot amount of ships are bound to local defense, less powerful and only a fraction of the entirety of the Imperium's fleet, counting industrial and merchant fleets.
The Imperium may be able to deliver a good many ships at once, but it takes a hell of a time to build them.

But one point needs to be made, though. Sectors of the Imperium are established from a top-down view of the galactic plane. Sectors are cubic zones, 200 LY wide (along the edge), on the average. Some smaller, some perhaps larger. They're divisions of the Segmenta, large swathes of the galaxy subdivied for administrative purpose, notably.
The typical mileage of a sector's battlefleet is 50~75 warships. A sector represents several sub-sectors, themselves covering around eight to ten planetary systems, sometimes more, sometimes only one.
Even if you pick two subsectors per sector, and give each subsector 8 systems, that's 16 systems per sector.

The Astronomican's 50K LY range pretty much defines how far the Imperium can extend before being unmanageable due to the miseries of the Warp. Then, of course, we should keep in mind that perhaps a fraction of that number could be FTL capable. There could be many warships maintained for local defense.

The circular area of the Astronomican is 3.1416 e10 LY². A sector has a top-down square area of 40,000 LY². There would be 785,400 sectors in the Imperium, more or less.
At the very least, 39,270,000 warships in total.
When considering the entire galactic volume (~3.3 e61 m³) and a sector volume of 6.17268 e50 m³, we get a maximum of 53,461,387,941.4 sectors.

Yet, how can it be that so many battles, even some crucial ones, notably during the massive Chaos campaigns, involve so few ships?
It's relatively difficult to pretend that most of the warships would be FTL incapable since even escort ships can move through the Warp.

Now, the concept of warship may have to be revisited, once used in the context of space combat, as a space capable ship built, armed and properly armoured for combat would fit the definition. This could be encompassing any small craft such as a bomber, which in WH40K are well armoured, heavily armed and often engaging much bigger warships, rather relevantly.
Let's also notice that the whole of the human fleet capacity could cover both local patrol fleets, and the long range capable and generally much heavier warships of the Imperium.

Today, coast guard fleet include ships just over 60 meters long, and easily fall under the warship definition.
The "superfast, large stealth missile" Skjold-class patrol boat is a 47.5 meters long fast attack craft, which considering its armament and hull, leaves no doubt about its battle capacity.
As similar examples, with different configurations, comes the Protector-class, Armidale-class and Fremantle-class patrol boats, respectively 32.6, 56.8 and 42 meters long.
The Osa-class missile boat was 37.5 meters long. Or the old HMS Lightning 26.7 meters long torpedo boat.

With WH40K bombers being plus 40 meters long, that works rather well, and could cover a whole range of even smaller crafts, and with some large Imperium carriers capable of launching 40 bombers, we can come to the understanding that a large carrier or smaller ones, plus planetary defense forces comprised of their own bomber squadrons, and then a few warships, battleships, cruisers or escorts, or smaller cratfs, easily explains the 50-75 average warship count, and fits with the scope of the typical BFG space battle.

However, there is a major issue with the rationalization proposed above, in that the Imperial Navy doesn't include crafts under frigates and destroyers as naval ships. Bombers are typically classified as aircrafts. The capacity of use faster than light drives doesn't seem to be the factor of difference, since non-FTL system bound larger crafts are considered warships.
The obvious element of difference there is merely a question of carriage and low altitude atmospheric fly.
Then, again, if some small warships were capable of hovering close to the ground, we could ditch that element as a factor in naval nomenclature, and bring everything down to a question of transport, in that if it can be transported, it's an aircraft, somehow.

Even the term boat doesn't necessarily imply the belonging to the classical imperial nomenclature under "warships": assault boats are launched from Emperor-class battleships for boarding operations.
Then remains the gunships, which I don't know where to put.

Which would mean that the other rationalization would be that a great bulk of the Imperium's naval power is about ships, perhaps smaller, which have traded FTL capacity for horsepower, weapons, shields and armour, making them just as good as bulkier FTL-transit capable ships.
It fails to explain, however, why so many systems seem to be literally underarmed, waiting for the Navy to come to the rescue. It would imply that those local crafts aren't up to the task of fending off anything greater than a single or few destroyers.






Connor MacLeod wrote: BFG Magazine #7
Thugh they were outnumbered by over three to one the Imperial ships blasted their way through the hive fleet and scattered the bio ships into small groups. The Tyranid piecemeal counter-attacks were beaten off by the awesome firepower of the heavily armoured and shielded Imperial ships. Their lances of fusion fire transfixed the organic hulls of the bio-ships and clouds of Imperial Navy fighters darted in to tear apart the crippled vessels. Within an hour the remnants of the hive fleet were dead and drifting, charred hulks spinning slowly through the void.


The battle had taken its toll of the combined fleet. Calgar had lost half his remaining ships and several Imperail ships had to be destroyed by the weapons of their compatriots because they had been boarded and overrun by the Tyranids.

Note the "fusion fire" lances (like mentioned in the BFG rulebook) as opposed to laser lances. I would presume that fusion lances are shorter ranged but more powerful than laser lances (much as a melta/multimelta is more powerful than a lascannon, arguably, but shorter range.)

Also note the battle with the Tyranids took the Imperials at least an hour, even though they were outnumbered 3:1)
On the topic of what a lance is, Connor's suggestion makes sense. From what I read on SBC, I remember a few members arguing that lances had also been presented as lasers. I found myself wanting to know the difference, and through my reading of several sources, it is rather clear that there are two types of lances, with the emphasis being put on the long range and heavy laser lances though.
13th legion clearly defines lances as "high-energgy lasers". The high energy is reminescent of the "high powered" bit quoted much earlier on, from the BFG rulebook.

That said, "lances of fusion fire" could also be the "fusion beamers", and therefore not as high powered as the laser lances.







Connor MacLeod wrote: Page 14
Bio plasma si treated like a lance shot...
..
Because it is a relatively slow-moving attack, like that of a bomber squadron, bio-plasma ignores shields.
The "slow moving/ignore shield" bit is curious for a number of reasons. One being, that to be an effective direct fire weapon it has to hit very rapidly (matter of seconds) voer thousands or tens of thousands of kilometers. This in turn implies a minimum velocity of thousands/tens of thousands of kilometers per second. Yet it ignores shields? there ware weapons that are just as fast/faster but do NOT ignore shields (weaposn batteries.)

Likewise it implies similar velocity for bombers and ordnance.
Void shields being partial to slow moving objects is nothing new. It's been noticed on Titans, and in BFG, torpedoes are said to ignore shields, although I don't recall speed precisely defined as the decisive element.
A Gargant's Ball munition can continue its course by rolling on the ground, and it also utterly ignores a Titan's Void shields and a Gargant's power fields.
Perhaps not ultra-consistent, it stills seems to be a recurring effect.









Connor MacLeod wrote: Page 6
The Endeavour class, lacking the speed for anti-pirate operations, ,is preferred as a covnoy flagship or a heavy escrot to larger capital ships of the line. Its heavy gun batteries can almost match the firepower of larger cruisers and it is capable of holding its own in the midst of a pitched battle.
Endeavours are light cruisers but pack nearly as much firepower of a heavier cruiser.
From time to time, I tend to be a bit lost with imperial sub-class nomenclature, notably when there are revisions. Following a fact from a couple pages earlier on, where we were told that power was mainly divided between engines and weapons, here we see that basically a lighter vessel is actually acting more as a defense platform rather than what its size might suggest: a light interceptor sort of bulky frigate with low firepower.
The bottom of the 7th page and the top 8th page of the GUT thread have info about the evolution on nomenclatures, but I would certainly advise to get some of the free PDF files from Games Workshop and then try to puzzle the things up with references from the SDN threads.







Connor MacLeod wrote: Page 7
Operating in this manner [One Endurance light cruiser plus 2-3 Endevaour light cruisers], the Ad Liberis was responsible for the destruction of nine Ork escorts as the War for Armageddon began above the high-g world of Pelucidar during a savage three-hour engagement before being ordered to withdraw by Admiral Parol.
"three hour" battle between nine Ork escort ships and a handful of light cruisers.
The escorts are generally weaker ships, Ork ones possibly even more, and the Imperium had four light cruisers.
Either the ships didn't have enough firepower to take down defenses that fast, or they followed a pattern of quick fire exchanges, then regrouping, moving around and even perhaps trying to find a hole into a flight formation, but that is not really "savage".
Boarding parties, however, would considerably lengthen the duration of combat.
When you see how, in general, the Imperium has enough firepower per ship to take down a ship of similar tonnage in a very short time, or how some dozens of bombers can cripple a massive warship in one fell swoop, it is very hard to consider that ships exchanged fire for three hours on and on without trying to find mitigating factors.







Connor MacLeod wrote: PAge 26
One of the planets in the sub-sector completes its capital ship construction project. The Planetary Governor presents your fleet with a brand new cruiser.
This is off of a game chart, so it may count as game mechanics, but it implies that many planets (Feral, Feudal, or other more advanced) can create at least cruiser-grade vessels with their available facilities.
Without the full context (the prior quotation was from the seventh page of the BFG magazine #12), it's hard to take this at face value. The implication would be valid if there were more details proving that this ability can actually be replicated on many worlds.
The capacity of very low tech worlds to be able to build new cruisers appears remarkable.







Connor MacLeod wrote: Page 27
An Inquisitor calls for an Exterminatus immediately. The next time you win initiative you will fight an Exterminatus scenario as the attacker. The Inquisition sends one of its ships along ot help. Treat the ship as a Dauntless class light cruiser with an Exterminatus weapon in the prow.
Light cruisers can do exterminatus, at least as per the exterminatus scenario. This is gameplay, so it may be considered conservative. We already could surmise from BFG that light cruisers could do so (they fall under the minimal definition of a "capital ship") of course, but this is a nice confirmation. Then again, the above also notes that this is an Inquisitorial ship, and those are notoriously more powerful than others.

Besides, we know in the fluff, for example, that Cobra class destroyers can conduct exterminatus with the right loadout too.
The vastest damage achieved by Exterminatus, in a short amount of time, is through the use of cyclonic warheads (previously virus bombs). They're totally technobabble weapons.
It is most important to notice that contrary to Connor & Co's claims, an Exterminatus may also be achieved as a localized operation, and could start with low power weapons, the final blow brought later on with the help of technomagical weapons:

"Xenos" features two Exterminati which start with low firepower. When I mean low, it's very low.
It's a key element in the understanding of an Exterminatus procedure.
I even recall some people at SBC arguing that there's been limited Exterminatus ops.

Not to say that since there have been planets which only had their surface scorched by the Exterminati, at any time a particular target would require a greater application of firepower, like a mining complex or fortress, said target would be dealt with adequatedly; this is not a reason to pretend that a fleet or flotilla would have to slag the surface of a world to a depth of several meters down with their conventional weapons.







Connor MacLeod wrote:
Lost Soal wrote: The last pieces comes from the musings of Larkin about his Long Las.
Only In Death, Pg29
Kill-shot at four thousand metres. He'd managed that once or twice.
Their is enough power range and accuracy in a Long Las for a skilled marksman to make a kill at 4km. While I don't know much about fire arms, if any modern rifle can match this I would be very surprised.
To get multi-km ranges you generally need very large-calibre rifles, like a .50 BMG sniper rifle. 7.62mm sniper rifles typcially won't go out more than 800-1000 meters or so IIRC. Even the .50 calibre rifles typically don't hit out to much more than a mile (though it has been known for skilled sniprs to hit out further.. in 2002 a Canadian sniper made a 2400 meter kill shot with a .50 BMG sniper rifle.) To reliably reach out to 2+ km though, you generally need a 14.5mm or larger round, and even then that's unusual (2.5 km would be tops.)

What's more, those are HEAVY sniper rifles - the ones designed particualriyl for heavy duty armour-piercing duties and whatnot. I doubt the long-las is even remotely comparable to something like that.
This doubt would be based on what? WH40K weapons aren't exactly of the smallest kind.
Lexicanum wrote: The lasgun mounts a bayonet lug, allowing the weapon to be fitted with bayonets or combat knives. The sniper variant of the lasgun, known as the long-las, is the preferred weapon of Imperial Guard sharpshooters. The barrel of the long-las is extended to bolster the weapon's accuracy. The barrel requires replacement every 20-50 shots depending on the power setting and cool down time. For this reason, the long-las is outfitted with a "slide-lock" barrel, which is easily locked and unlocked from the weapon's housing. Mad Larkin from the Gaunt's Ghosts novels by Dan Abnett carried one such modified Lasgun.
Plus this is a long range sniper weapon that largely ignores gravity over such short distances, and this Larkin guy only scored a kill once, perhaps twice (he's not sure) at 4 km.

Compare this to the M82A1 heavy sniper rifle:
Specifications:
  • Weight: 31 lbs
  • Length: 48 or 57 inches
  • Barrel Length: 20 or 29 inches
  • Cartridge: 12.7 x 99mm, NATO
  • Caliber: .50 BMG
  • Action: Recoil operation, rotating bolt
  • Sights: 10x telescopic
  • Rate of Fire: Semi-automatic
  • Muzzle Velocity: 853 m/sec
  • Maximum Effective Range: 1,800 m
  • Maximum Range: 6,800 meters
  • Feed System: 10-round box magazine
The record by one of the Canadians was over 2400 meters with a McMillian Tac-50, with low drag ammunition. The maximum effective range of this weapon (assuming the builder didn't lie about the stats) is 75% of the record held by the Canadians.
As it's easily noted on rifle/shooting forums, official claims are often exagerated.
So basically a long-las in a skilled sniper's hands is between 2-4x longe ranged than a modern rifle.
An extremely rare kill, for a weapon that would logically be more massive than a traditional lasgun. The lasgun has the advantage that what you see is what you can hit, simply because no matter if gravity or difraction affect the photons' path, since light managed to bounce off your target back into the ocular, in theory the lasgun's bolt will travel back along the same route.
Then, of course, comes the question of how well the lasgun is calibrated.

We don't know the size of the target.
As a side note, you can generally expect a regular rifle to have roughly 1/2 (7.62mm or .308) to 1/3 (most .50 BMG) the range of a sniper rifle for precision shots, and probably comaprable range against groups (Point target vs area taget IIRC. For example, an M-16 has a point target range around 450-500 meters, and an area target of around 800-900 meters.)

This would mean you could probably expect a regular lasgun to hit a "point target" at between one and a half to two kilometers, and "Area targets" of around 3-4 km, roughly.
Or perhaps not. The evidence for this reasoning is rather sketchy, at best. If we pick the percentage from above (75%), then by extrapolation the maximum effective range of the sniper lasgun would be three kilometers, and thus, half of that would be 1.5 km, and 1 km for a third.
That is without knowing how a long range lasgun has its range improved. The loss ratio between a sniper lasgun and a traditional lasgun could be very different from the one that applies to current projectile rifles.
It would actually need to be different, to fit with books, wherein ranges rarely reach beyond half of the highest value presented just above, and kill-shot ranges are even shorter.





Connor MacLeod wrote: Battlefleet Gothic magazine #15

Page 18
The Seditio Opprimere was reduced to a near hulk at the Battle of Prandium. It was rebuilt as a gunship with powerful long-range plasma lances to give the Ultramarines stand-off fire support when fighting Tyrannids using the new fleet tactics. This severely compromised the ability of the barge to deploy trroops.
Mention of "plasma lances" - the third kind of lance (the other two being laser and fusion lances) I have seen for Imperium warships. It's also implied to be both mass/volume intensive and very long ranged/powerful (how much so isn't sure.)
Nothing really excludes the idea that plasma lances couldn't be just another wording of the fusion lance/beamer. Plasma, after all, can be obtained by fusion, and infantry weapons shooting plasma are related to fusion from time to time. Perhaps only their increased range would make them different.
Perhaps they are not capable of prolonged uses, with considerable cooling down timespans.







Connor MacLeod wrote: BFG magazine #16

Page 4-5
In seconds, Urthwart became a victim of the aptly named Planet Killer - the world and all it had ever contained committed instantly to history by this greatest of Abbadon's machineries.
Planet is destroyed in "seconds" by the Planet killer. This probably qualifies as an "outlier" since usually it takes around half an hour to an hour to achieve that. Unless it was a very small planet, or unusual in some way. Given the warp/daemonic properties inherent in the Planet Killer, its also quite possible that some "Exceptionally fast" kills do occur, just like in a few cases we have exceptionally slow ones.

A second possibility is that something on the planet itself blew up. We know from the St Josemane's hope example that planetary powerplants can be rigged to blow up and mass-scatter a planet in an Exterminatus, so its possible that the Planet Killer can take advantage of this somehow.

Alternately, since IIRC this was durinb the 13th Black crusade, the Planet Killer may have simply been upgraded, and this just represents a vast improvement in its firepower.
Or the weapon's power was used differently, to affect the whole surface instead of that 30 minutes long drill thing.
It's not like weird spreading/technobabble effects of weapons at such scales would prevent the capacity of a planet killer to spread over the surface of a world. After all, if the video game Firewarrior cutscene is to be taken at face value (aside from the extremely messed up scales), that's pretty much how the cyclonic torpedo spam ends, with a big fireball and stuff that runs over the planet's surface.

I may quote myself in a possible APK thread.









Connor MacLeod wrote: PAge 20
There could never be enough warships to fortify all the millions of worlds in the galaxy that make up the Undying Emperor's domain, and some planetary populations may go decades or generations without once having the privelege of an Imperial Cruiser silently gliding into orbit overhead.
"millions of worlds" in the Imperium.

There could "never be enough warships to fortify all the millions of worlds" If we assume "fortify" means half a dozen vessels (sevearl cruisers and a number of escrots, ther could be no more than 12 million ships total, 1/3 of which cruisers. Note that there IS a differencec between "fortify" and "patrol" - a single cruiser or a flotilla of escorts could not realistically be considered sufficient to fned off any sizable naval force save pirates.

As far as the last part: "decades" or generations implies a visit of a cruiser once every 20-100 years. If we assume each planet is viisited in that timeframe once, this would mean between 20,000- 100,000 cruisers, minimum. At 10 million planets its 100,000-500,000 cruisers.
10 million planets? Did the figure go up by one order of magnitude between the first capital of this paragraph, and the final period?

There are sources that peg the Imperium's world at "a million".

And do we know that all worlds are inhabited?
14; a celestial body (a planet).
A system under imperial control would typically count several planets, even several stars in some cases (up to 6 or 7).

If you consider our system, there's between 9 and 10 planets (allow me to keep my distance from ever changing definitions), with only one naturally inhabitable. Ours.
That's simply 10%, roughly.

There's the following interesting part from the BFG rulebook which didn't make it in Connor's thread:
BFG rulebook, p.45 wrote: PLANETS
Less than 1% of systems have planets orbiting a solitary star in the manner of ancient Terra. Even so, there are millions of star systems containing billions of worlds scattered across the galaxy. Most planets are either desolate, empty and airless, or surrounded by an atmosphere too noxious to support life. In the Gothic sector there are over two hundred inhabited worlds and tens of thousands of other planets. Planets often becomes the focus of space battles as opposing fleets attempt to establish forward bases or extend their control throughout a contested system.
So, basically, we learn that a system is considered acquired when a central world is under control. Worlds in the life band of a star system are where "the bulk of a system's defences are built" (p. 43).
Some colonies and hive cities can be found closer to the local star in certain systems.
This sufficiently narrows the scope of worlds that really need to be defended or even visited.
Gothic sector has +200 inhabited worlds, and at least 20,000 more worlds. So on a total of 20,200 worlds, only 0.99% are inhabited.

Perhaps even more telling, is that on the other side of the spectrum, if the Gothic Sector counted a total of 100,000 worlds, then there would be only 0.2% of its worlds that would be inhabited.

Now, let's return to Connor's ship count based on the scarce visit of ships to planetary populations, and let's get some numbers here.
With 1 million worlds, say you need 20 years for all planets to see a cruiser once (and that's picking the fewest decades possible), it means that within 10 years, only half your worlds will have seen a cruiser, and only a quarter within 5 years.
It puts the maximum number of cruisers at 50,000, so that at the end of the 20th year, and for the 21th year, your ships can return to the first batch of planets they visited for another round.
That's in the absolutely best conditions imaginable.

Less worlds with noticeable planetary populations, and with time cycles greater than 20 years, will significantly cut the numbers, by a rather considerable deal.
For example, 100 years instead of 20 brings the number down to 10,000 cruisers.
10% of the Imperial worlds being significantly inhabited brings the number down to 1,000 cruisers.
Or only a hundred cruisers when only 1% (well actually 0.99%) of the Imperium's worlds are inhabited. 1% is obtained from the ratio of inhabited worlds in the Gothic sector, as seen above.

Now, IF the Imperium did control 2 million worlds, that would make a couple hundreds or thousands of cruisers tops.

On a mildly related note, a sub-sector such as Bhein Morr contains many systems:
Balaam, Bhein Morr, Duran, Elysium, Fularis, Kharlos, Krool, Luxor, Mastado, Oechalia, and Stranivar. (11)
The Lysades subsector contains the following systems: Arimaspia, Bladen, Boetia, Coimbra, Corlini, Saviour, Schindlegeist, Sicyon, Skagerrak, Tarantis, and Vindalex. (11)
Source.

You can find Connor's fleet numbers here.

This is clearly another big topic, so at some point, I may take a deeper look at this subject.






Connor MacLeod wrote: Page 20
Despite these portents of doom, Belis Corona was not without its defences. It is home to vast orbital dockyards, decomissioned ship reserve fields and repair facilities that dwarf even those of Armageddon's St. jowen's Dock in importance ot the security of the Imperium.
Seems to be a sector base if not the naval sector base. Has its own reserve fields as well as its own major shipyards (bigger than aRmageddon's which means they're significant.)

This also implies that reserve fleets and major yards are present at least one per every sector (thousands or tens of thousands of such yards in the Imperium, in addition to the Segmentum bases, whch are perhaps even bigger and the Forge world yards.) Given the probable size of such yards, we might anticipate hundreds of thousands, if not millions of additional vessels in shipyard reserves, easily.
There's no proof that the conditions that apply to Belis Corona establish a standard.







Connor MacLeod wrote: page 28
Deep within the bowels of the ship, archaic weapons of unimaginable power hummed to life, and the Master of Gunnery personally supervised the loading of the awesome Nova cannon as gangs of men numbering in the dozens opened the thirty-meter wide breech to accept the massive, multi-ton shell being trundled into place by more lash-motivated gangs pulling on an enormous overhead gantry under the careful eye of gunnery chiefs and Mechanicus adepts.
This Nova cannon, mounted on a Victory-class battleship, is thirty metres in diameter. This is smaller than the fifty metre diameter Nova cannon mounted on a battleship in Warriors of Ultramar (then again that one traveled at barely 2% of c, whereas in BFG and Rennie's novel Shadow Point specify that nova cannons travel at near-c. Go figure.)

In any case, assuming a 30 meter diameter, 60 meter long cylinder the density of water traveling at .8c, the shell will mass about 42,500 tons (4.25e7 kg). At .8c the KE of the round is 2.55e24 joules. Momentum for the shell is 1.7e16 kg*m/s. This is very conservative, given that the projectile could arguably be longer (as noted, if the shell is of similar proportions to a torpedo, then it will be much more massive) and my absurdly low density (it should be at least several times as massive on density alone.)

The velocity could be much higher as well. At .9c the KE of a 42,000 ton shell goes up to 5e24 joules. (momentum 2.633e16 kg*m/s) At .99c the KE goes up to 2.33e25 joules (momentum of ~9e16 kg*m/s)

What I find also confusing is that, unlike a great many other weapons (bombardment cannon, lances, torpedoes, etc.) a nova cannon fires only a single shell. If Nova cannon come in different sizes (in a battleship you should be able to easily mount several nova cannon) why they can't do more than one smaller type. It would seem to make more sense for the weapon (especially if, as noted before, Nova cannon are of similar scale to Bombardment cannon or the larger kind of torpedo.) Heck, maybe they do, or it depends on ammo or design....

Note that given the recoils (momentum) above, we can estimate the accleerative capabilities of a warship. Assuming iron, 95% empty space, and a 7 km box (height/width 1/5 the length), the estimated mass of a battleship would be ~5e12 kg (5 billion tons) with a recoil between ~2e16 and 9e16 kg*m/s would be between 4,000 and 18,000 m/s^2. which again as I noted is very conservative for various reasons (the density of the shell alone could justify the accelerations being considerably higher.)
All these Nova cannon calcs are good, as long as you focus on a limited segment of the whole information about this special weapon. They don't take into consideration the problem that the weapon cannot slow down on its own, making a poor blast effect, and certainly not one as suggested by the BFG rulebook.
Also direct hits against Roks are hardly consistent with the calcs above, yet no mention was made about Roks being shielded, reinforced or benefiting from any Waaagh effect whatsoever (which is an excuse used rather often to defend high numbers).
Last edited by Mr. Oragahn on Thu May 06, 2010 8:52 pm, edited 3 times in total.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Sun Oct 18, 2009 12:06 am

Page 6.
Connor MacLeod wrote:
Luzifer's right hand wrote: These are ships which can accelerate to/decelerate from 0.75 c and more.
You just need huge amounts of fuel to get the energy to accelerate your reaction mass that way, that does not really help.
Unless your reactors cheat of course, but why assume that the reactors cheat instead of the drive?
the fuck? Have you actually DONE any research into 40K reactor systems? how much do you know? did you even bother reading the prior pages, because we just got done discussing plasma reactors a few pages ago.

1. Squat "neoplasma reactors" being powered by "Warp cores" contained/controlled by a "Zero energy" containment field (Codex Imperialis and the Inquisition War novel "Chaos Child")

2. Spacefleet stuff early on indicates plasma fuel is 1000x better than "conveitnonal nuclear fuels", which ought to include fusion if not antimatter. It also implies that plasma fuels are alot more complicated to create than fusion reactants (more akin to antimatter really.)

3.1. Plasma reactors can "re-use/recycle" its fuel mulitple times (Despite being arguably "annilation grade or better" reactors) and have implied insanely long durations (3rd edition rules.. someone posted the excerpt in this very thread.)

3.2. The ramilies class Star fort has a "hyper plasmatic" energy system that also has an endurance of millenia, which also points to insanely long timeframes.

4. Earlier 40K supplements had plasma grenades that involved a "matter/energy transformation process", which is exotic.

5.1. The Last Chancers novel "thirteenth Legion" have all manner of qualities associated with plasma reactors (needing exotic materials working as "catalysts" and "ignition elements"

5.2. More than that, it mentions plasma reactors as being a "self fuelling" process. And once you start them up, you don't shut them down. (but you can overload them.) Without its containment fields, a plasma reactor is highly unstable, going into a chain reaction that will utlimately detonate.
What's more, multiple plasma reactors can "fuel" each other's own chain reactions and apparently create larger destruction.

5.3. Taken as a whole, with all the other data we know, 40K plasma reactors are VERY exotic, along the lines of stargate Naquadah reactors or Weberverse hyperspace taps (or some theories as to how hypermatter reactors work, actually). Which probably means they are at least partially an extradimensional tap coupled with a conventional reactor (probably feeding the tap and allowing it to occur.)

5.4. On top of that, the "stellar levels of energy" needed for a mere cruiser's WARP trranslation are more than ample corroboration for the other figures I've stated. And that has been LONG available in quote form. Nevermind the established acceleration figures, or the recoil bit for the nova cannon (which alone substantiates the magnitude of my calcs, unless you're going to tell me when a ship fires its nova cannon it takes minutes to slow the fuck down too...)
Quoted for the multiple references regarding reactors.

1. The Squats (dwarves of WH40K, who may return as the Demiurgs), disappeared for several editions of the rulebooks. Apparently their power generation technology didn't save them much.
Let's note that "neoplasma reactor" is just a vague syntaxic construct, that the fact it was powered by a "Warp core" heavily suggests that the Squats used the energies from the Warp, to an unknown percentage. Finally, the fact that such an equilibrium was maintained by a "Zero energy" containment field means pretty much nothing at all.

2. No fuel could be a thousand times better than conventional nuclear fuel since perfect annihilation would only be about two orders of magnitude more potent than humanly known fusion based production of energy (1). So the efficiency has to be relative to something else, at the very least partially.

3.1. The Imperium doesn't control matter annihilation, and a fusion reaction can be repeated as long as there's matter left to fuse and as long as the technology allows the sorting of the waste from the useful.
Nothing says that the recyling is absolute or even any close to a medium efficiency.

3.2. The Ramilies Star Fort is powered by a technology that eludes the Imperium though:
Armada Imperial Vessels, p. 31 wrote: The Ramilies class star fort has formed a vital lynch pin in Imperial strategy since the earliest days of the Great Crusade. It was designed, according to Mechanicus legends, by the hitherto unknown Artisan Magos Lian Ramilies from STC materials captured in the purgation of the 'Stone World', Ulthankx. The Hyper-plasmatic energy conduction system used by the Ramilies is barely understood by the Techpriests in current times, but thanks to the STC system it is still reproducible and has guaranteed endurance of over 3,000 years.
So the endurance isn't even due to the reactor being impossibly tough, but because despite their lack of understanding of how the reactor works, the Tech Priesthood still manages to reproduce parts to maintain the cores.
Using the Ramilieses as evidence that the Imperium can build such powerful reactors, themselves as evidence of insane firepower, is nonsense.

4. Matter/Energy transformation process may sound exotic, but just about any energy production can be described thusly. Not to say that what is exotic is how the fireball is maintained. Besides, it's a weapon, not meant to be a stable reactor whatsoever. Then, again, Connor massively wanked out the yield of such grenades. Conservative, as he said (...).

5.1. Which is meaningless. Not to say that earlier material also points to coveted fission power generation, considered one of the holy grails of the STC, and powering Titans.

5.2. Self-fuelling is nothing exotic. This is aptly detailed in the relavant thread.

5.3. Taken as a whole, some reactors from some civilizations are exotic. Those of the Imperium hardly are deeply eluding though. And for the note, there is no proof I know of that stipulates that naqahdah (Stargate franchise) has an energy density greater than annihilation, although the ore is clearly exotic considering the abilities of one of its isotopes.

5.4. It's almost sad to see people use "stellar levels of energy" as a supposed iron-hard argument. There's a certain level of desperation in that.
Also, if the engines could be used to compensate for the energy figures Connor derived from the description of the Nova weapon, it should be fairly easy to find references about how those engines can then easily destroy an enemy massive warship on its tail, or burn the surface of a continent crisp with the merest acceleration hick up. :)








Connor MacLeod wrote: Last BFG magazine updates.. about fucking time too.

BFG magazine #18

Page 9
The Imperium's defenses were thinly spread, even around the Caidan Gate where the so called Bastion fleets stand as the largest permanant Imperial Navy element outside of the Solar System.
Sol System's naval forces are larger than the bastion fleets around the Cadian gate (meaning many hundreds of vessels, possibly thousands.) Presumably this means only naval ships, not including the Inquistion, Arbites, AdMech, or Astartes vessels that might be there.
Most interesting. If anyone can lock a fleet number for the Sol System, then you pretty much know that any other fleet size elsewhere, safe perhaps at Cadia considerings its extreme importance just behind Terra, no matter the "bastion fleet" label, will be smaller.
And I don't see why all these factions wouldn't be counted as part of the Imperium.







Connor MacLeod wrote: PAge 10
Where the Imperial Navy had been forceed to divide its assets across hundreds of worlds at the outset of the war.

...

Where Imperial defences had been overstretched at the outset of the war, they soon stood reinforced by dozens of neighboring battlefleets. Tiny patrols, at first hopelessly outnumbered nad overwhelmed by Abbadon's invasion, mustered together into battlefleets numbering hundreds of vessels.

...

To win the greater war now the wise (and not least amongst them, Admiral Quarren) realised that a handful of crucial fronts must be all to which the Imperium committed.
Description of the Imperial dispostion of forcees and how it altered with the onset of the 13th Black Crusade, and how it influences tactics.
Some more info on fleets.
I'd note that the hundreds of patrol ships mustered into bigger battlefeets that made a difference is merely a rethinking of ship deployment after things were going bad for the Imperium. Destroyers can come as 750 and 1000 meters long ships.

Now, dozens of battlefleets (24 to 96) with hundreds of ships each (200 to 900), that makes a bracket of 4800 to 86,400 ships, distributed over several hundreds worlds. The smallest concentration is +5 ships per world, the highest concentration is 432 ships a world.







Connor MacLeod wrote: Page 15
with Chaos fleets being caught ill-prepared as they hung in orbit over a dozen worlds, disgorging the hordes within.
Indicates the Imperium struck at a dozen different planets (out of a Thousand potential, or "hundreds") attacked by Chaos.
Or ought of a 200 hundreds potential (would fit with the inhabited worlds of the Gothic sector).
But why not go with, say, tens of thousands, or hundreds of thousands of planets? After all, it's still only hundreds times n. (That's sarcasm, in case you don't get it.)
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Re: WH40K - 40K misc numbers... (SDN)

Post by Jedi Master Spock » Sun Oct 18, 2009 2:47 am

Mr. Oragahn wrote:2. No fuel could be a thousand times better than conventional nuclear fuel since perfect annihilation would only be about two orders of magnitude more potent than humanly known fusion based production of energy (1). So the efficiency has to be relative to something else, at the very least partially.
Hang on one minute. I know this may seem a minor pedantic detail, but modern nuclear reactors get on the order of tens of gigawatt-days - i.e., petajoules - per ton of reactor material. I.e., terajoules per kilogram of actual fused output heat. The efficiency of the reactor at producing useful power goes through the efficiency drop of the steam turbine, so less than a terajoule per kilogram net output for a nuclear reactor is not out of the question.

Theoretical maximum for fusion (hydrogen to iron, 100% efficiency) is almost a petajoule per kilogram (800 TJ). If the "conventional" nuclear power plants referred to are fairly primitive fission plants, of fairly robust designs that would actually be useful, and a plasma reactor is a near-100% efficient complete-fusion design, it would be quite close to a thousand times as potent.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Sun Oct 18, 2009 5:19 am

Jedi Master Spock wrote:
Mr. Oragahn wrote:2. No fuel could be a thousand times better than conventional nuclear fuel since perfect annihilation would only be about two orders of magnitude more potent than humanly known fusion based production of energy (1). So the efficiency has to be relative to something else, at the very least partially.
Hang on one minute. I know this may seem a minor pedantic detail, but modern nuclear reactors get on the order of tens of gigawatt-days - i.e., petajoules - per ton of reactor material. I.e., terajoules per kilogram of actual fused output heat. The efficiency of the reactor at producing useful power goes through the efficiency drop of the steam turbine, so less than a terajoule per kilogram net output for a nuclear reactor is not out of the question.

Theoretical maximum for fusion (hydrogen to iron, 100% efficiency) is almost a petajoule per kilogram (800 TJ). If the "conventional" nuclear power plants referred to are fairly primitive fission plants, of fairly robust designs that would actually be useful, and a plasma reactor is a near-100% efficient complete-fusion design, it would be quite close to a thousand times as potent.
That seems to be a lot of ifs. Besides, the difference between 630 TJ and 180 PJ is a factor of 285.71. If I get your point clearly, the factor corresponding to 800 TJ is even lower, down to 225.
So for the "thousand times better than conventional nuclear fuel" bit to work, said lower grade fuel would have to be worth 180 TJ per kilo, tops.
I'm sure the quality of a fuel can be defined by other characteristics than sheer energy density. It could be relative to the purity, toxicity of the waste, recycling and else.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Jedi Master Spock » Sun Oct 18, 2009 5:40 am

Mr. Oragahn wrote:That seems to be a lot of ifs.
It is.
Besides, the difference between 630 TJ and 180 PJ is a factor of 285.71. If I get your point clearly, the factor corresponding to 800 TJ is even lower, down to 225.
26 GWd/T = 2.2 TJ/kg. There are actual reactors around this burnup range. A 36% efficient heat engine attached to that for generating "effective" power - in a similar range to many gasoline or diesel engines - would bring you down to 1/100th of the ~800 terajoules/kg that is the limit for atomic fusion.
So for the "thousand times better than conventional nuclear fuel" bit to work, said lower grade fuel would have to be worth 180 TJ per kilo, tops.
I'm sure the quality of a fuel can be defined by other characteristics than sheer energy density. It could be relative to the purity, toxicity of the waste, recycling and else.
180 PJ/kg is not the figure for fusion fuel; that's the figure for antimatter. Assuming the addition of a kg of matter, so it's really 90 PJ/kg. Raw annihilation is about a hundred times more potent than any kind of atomic fusion, but it's within the 10^4-10^5 order of magnitude more potent than modern fission reactors - tens of thousands.

If you were running a reactor similar in efficiency to modern reactors, and running it on something less enriched - say, non-enriched uranium - we could even say that the comparison is to less than completely primitive nuclear reactors. The only types of reactors we expect to be able to get above a thousandth the potency of pure annihilation are fusion reactors, and even less advanced versions of those may be less than that.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Sun Oct 18, 2009 1:24 pm

Jedi Master Spock wrote:
Mr. Oragahn wrote:Besides, the difference between 630 TJ and 180 PJ is a factor of 285.71. If I get your point clearly, the factor corresponding to 800 TJ is even lower, down to 225.
26 GWd/T = 2.2 TJ/kg. There are actual reactors around this burnup range. A 36% efficient heat engine attached to that for generating "effective" power - in a similar range to many gasoline or diesel engines - would bring you down to 1/100th of the ~800 terajoules/kg that is the limit for atomic fusion.
But that would mean their conventional nuclear fuels are that inefficient, in light of the super duper fuel that's supposedly 1000 times better... if, again, we consider that what it is a thousand times better in is at delivering energy per gram.
So for the "thousand times better than conventional nuclear fuel" bit to work, said lower grade fuel would have to be worth 180 TJ per kilo, tops.
I'm sure the quality of a fuel can be defined by other characteristics than sheer energy density. It could be relative to the purity, toxicity of the waste, recycling and else.
180 PJ/kg is not the figure for fusion fuel; that's the figure for antimatter. Assuming the addition of a kg of matter, so it's really 90 PJ/kg. Raw annihilation is about a hundred times more potent than any kind of atomic fusion, but it's within the 10^4-10^5 order of magnitude more potent than modern fission reactors - tens of thousands.

If you were running a reactor similar in efficiency to modern reactors, and running it on something less enriched - say, non-enriched uranium - we could even say that the comparison is to less than completely primitive nuclear reactors. The only types of reactors we expect to be able to get above a thousandth the potency of pure annihilation are fusion reactors, and even less advanced versions of those may be less than that.
Yes, I know that the 180 PJ is for antimatter. But my point was that with no sign of antimatter cores in use in the Imperium thus far (but perhaps I'm wrong), and with the alleged super fuel being a thousand times better than conventional fuel, then working backwards from perfect annihilation, which would be the maximum achievable, you couldn't have a super fusion fuel unless the conventional nuclear fuels, such as those used in anything but vessels, were of a poor quality, one not really looking like it could fit with claims of gigatons or more.

After all, the 1000x times better fuel is said to be used in vessels.

The the idea that non-vessel power cores would be particularly inefficient (all relative) doesn't seem to be popular at SDN, and generally, as they assume an already very good nuclear fusion technology powering anything aside from vessels, they consider that anything better, especially a thousand times better in producing energy, has to be exotic and physics-raping.

We had, in another book, ships of the Imperium attacking an Ork fleet, and at some point, an imperial ship shot at a Rok and blew it up sky high because it had triggered a reaction with the stocked nuclear fuel. Even the commander of the imperial ship laughed at the fact that only the Orks would fill an asteroid with huge amounts of uranium or something like that. And yet Ork ships aren't exactly doing a poor job against imperial cruisers and battleships.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Thu Oct 22, 2009 11:10 pm

More stuff about Rogue Traders that I'll skip, to get to some figures of the typically arguable flavour, on page 7, along other disputable claims or forgotten observations.




Connor MacLeod wrote: Next update is a WD article, should be familiar as others have mentioned it before. I dont know when I'll update next, maybe after the holidays. Anyhow...

White Dwarf 287

Page 66
They reported a four-planet system with only the second world residing in the habitable zone and confirmed that Seneschal was an incredibly ancient star.
There are four planets (plus an Asteorid belt) in the Seneschal system. The second planet is roughly in the "habitable zone" which placese it roughly 1 AU out (its between 1.2-1.5 AU in the magaizne.)
Keep that in mind for later.







Connor MacLeod wrote: Page 66
Gakal is the outermost planet of the Lorderne system.

....

Within a few hours a fleet of system ships had been despatched from Issakkan, the third planet of the Louderne system and the system capital. There were fears that even fifteen system ships and defence monitors would be unable to prevail over a single Necron Vessel but by the time they arrived the Necrons were gone. In the time it had taken the Imperium to react all human life on and around Gakal had been brutally exterminated.
It took "a few hours" for fifteen system defence vessels to reach the outer edges of the system from the haibtable zone.
Too bad we don't exactly know the size of that system.
It better be big. That said, this is another nail in the coffin of intrasystem jumping.
We can also guess that it took "a f ew hours" for the Necrons to supposedly render an extinction event on the planet, a feat that would require hundreds of GT/sec minimum.
Perhaps through a technobabble super WMD?
Even their infantry level basic weaponry is extremely complex.





Connor MacLeod wrote: Page 68
"Fifty miles a day, we march across the sands."
- Drinking song of the 8th Cadian Regiment.
- Assuming a straight 8-12 hour march time, they can move at roughly 2-3 m/s. That seems rather impressive in a desert situation, but I have no clues how this might stack up to modern soldiers.
2-3 m/s for a human, with military gear through sand, is a bit silly.
A good day walk, if it's more of the exceptional sort of walk (see one a week for example) doesn't need to be clocked under 12 hours.
Pick 16 hours, six one-hour breaks, and counting on a long nap afterwards, that's 80,467 meters a day, for 1.4 m/s.
Again, I'd hope Connor not to consider a folksong to be taken so literally that it should represent a standard.
- You'll sleep when you'll be dead.

And of course, it's a song.






Connor MacLeod wrote: Page 68
The other [ship] was Stormchild a Cobra class destroyer, assigned to act as an escort.

...

Perhaps more pertinently the Stormchild carried two special torpedoes with thermal warheads capable of cutting through the crust of a world. The Torpedoe's warheads were cyclonic charges which could destabilise the core. In the entire sector there were no others like them. The Adeptus Mechanicus had hoarded them for thousands of years, maintained them with diligent and pious worship so that they would be ready to destrroy a world. These two torpedoes were planet killers and were more valuable than every man in the expedition.
Stormchild is outfitted for extrimnatus. The torpedoes it fires are "dual warheads" - one a thermal warhead to "cut through the crust of a world" to an unknown dimension, but at least 30-40 km deep, possibly more. It probably is more, given its stated to "Destabilize the Core" and "Destroy the world." Given that its meant to wipe out the underground tomb world, it probably does a nasty job of fucking up the surface of the planet (massive shockwave or melting/vaporization.) Not neccesarily mass-scattering, though. But they are very rare examples of warhead, probably technobabble, even for a cyclonic.

To "melt through the crust" assuming a 20 meter diameter (to get through the crust) would require some 60,000 TJ minimum (about 15 megatons.) Vaporization would require at least 6-7x that figure. Assuming a much bigger hole results in larger calcs. Assuming it blasts ou ta 30 km diameter crater, it would require something on the order of tens of gigatons to accomplish. And that's not even its primary warhead. Penetrating the mantle or more could be much more intensive.
And drilling or NDFing its way down would require levels of energy impossible to quantify.
Other than that, it's a super technobabble type weapon of doom. Two heads, millenia old and rare.






Connor MacLeod wrote: Page 69
Leaving Stormchild running on minimal power in the asteroid belt, the St Aspira moved in-system to Seneschal II as fast as its engines could manage. All through the approach its powerful surveyors explored the planet's surface.

...

The entire surface of the planet had been stripped of natural structures, no seas, rivers, mountains or forests were evideent. Instead there were tombs the size of continents, inlaid inscriptions with sigils the size of Titans and raised necropolis' that would dwarf any Imperial Hive.

...

Within a few minutes of Flintlock's party entering the crytp, vox contact with the search party was lost and only an occasional terse psychic message from Flintlock's sanctioned psyker to St Aspira's asteropath informed them of what happened.
1.) The "storm child" is in the asteroid belt, which may give us a rough indicator of how far out if we assume the system is similar to ours.

2.) The Necrons (possibly) have the transport capacity (or firepower) to remove "all natural resources" from a planet in an unkonwn period of time with unknown weapons. This rqeuires considerable energies.
1. Remember the description of the Seneschal system? (top of the post) Not very Solar like. Four planets. More than very likely smaller, actually.

2. Or perhaps they sucked the energy to build those tombs or something. Perhaps they opened some warp portal that sucked matter through. And numbers? They seem to be huge.





Connor MacLeod wrote:
Before any help could arrive, the Benedicto suffered a series of catastrophic explosions and broke up, its demise enscribing a fiery arc in the upper reaches of Macragge's atmosphere.

Even as the wreckage was rainign down across hundreds of kilometers of northern tundra...

...

... the adamantium canister protecting it [gene-seed] should have survived the impact and had to be found and secured at any cost.
Adamantium cannister survived the explosion of the shuttle and atmospheric reentry and subsequent impact with the ground (as did the contents.) This probably tells us something about the thermal and structural tolerancees of such materials (since we're talking a probable hypersonic/hypervelocity impact - meaning lots of energy. And atmospheric heating would also be significant - modern amterials generlaly cant handle that without special modifications.)
Not necessarily. It could have, for example, been stuck in a piece of the wreckage and thus never had to deal with the full blunt of heat up due to friction.






Connor MacLeod wrote:
"By the Throne, these hellspawn are fast!" yelled Brother Arrain, his bolter spitting death and blowing an advancing Genestealer apart in a spray of chitin and blood.
Genestealer blasted apartt by bolter fire from a Space Marine weapon. According to IA4, a Genestealer masses some 300 kilograms, about 4x the mass of a human. A single grenade (as indicated in the "Grenades and guts" can completely obliterate a human torso (call it about 30-40 kilos of mass) - we can infer that a boltgun volley is therefore equal to about 8-10 grenades or so. A frag grenade has about .23 kilos of TNT, so we might expect said volley to be potentially equal to up to several kilos of TNT, although they aren't detonating all at once, and the kinetic impactor aspect of the bolt round can be something of a factor. Even a fraction of that yield (say half a kilo) would be substantial in terms of firepower

It would also suggest, even at the low end (assuming 6 shells containing 50 grams of explosive equaling half a kilo of TNT) that Imperial explosive sare considerably more powerful than modern ones. (something we've encountered multiple times - this just helsp reinforce the idea.) And this is consistent behaviour with bolt guns in other examples too.
On a principle similar to laser pulses, a series of lesser explosions will be more effective to cut a target in half than a single blast that would correspond to the total power of each charge.
Where I'm going here is that I don't see a mention that the creature is entirely turned to mashed potatoes. All I read is that it's blown apart. You may also think that blowing up the beast's torso would suffice to match the observed (hyperbole heavy) effects.
Also, a genestealer may be heavier, but consider the extra mass of the head, and the two extra heavy arms added to the already two long and more human-looking arms, that short but thick tail, and the elongated torso.
The creature's torso mass needs not be more than slightly denser than a human's, and pouring a rain of explosive ammo into the torso will be more than enough to rip the creature apart.
What is more bizarre is that despite working from a ratio of 300/80 (genestealer/man) that corresponds to 3.75, Connor generously rounds this up to 4, and finally comes with a conclusion that the volley must be the equivalent of 8 to 10 grenades, and not 3.75 grenades, merely based on the effects, not on a possible round count from some other source.
Note that considering the repartition of mass in a Genestealer, you may not even need to get a yield worth of 3.75 grenades deposited into the torso to blow the creature apart.

Not to say, by the way, that bolt rounds would penetrate the target, contrary to a grenade, and that makes a hell of a difference.

Pretending that the volley needs to be worth 8-10 grenades is one of those "conservative" figures.





Connor MacLeod wrote: Space Hulk (video game) - from the fluff section

Page 2
Whereas it once took centuries forhuman spacecraft to travel to Sol's closest neighboruing star, the same distance could suddenly be covered in just a few hours.
"Centuries" implies tens or hundreds of light years. Covering a similar distance in a "few hours" implies velocities well into the tens of thousands of times the speed of light, if not hundreds of thousands.
Video game fluff... methinks this is not going to be acknowledged as rock solid evidence in debates, no matter the claim made. Well, if debates there are.

On the topic of moderating passion, I'll quote andrewgpaul:
andrewgpaul wrote:
Connor MacLeod wrote: Space Hulk (video game) - from the fluff section

Page 2
Whereas it once took centuries for human spacecraft to travel to Sol's closest neighboruing star, the same distance could suddenly be covered in just a few hours.[
"Centuries" implies tens or hundreds of light years. Covering a similar distance in a "few hours" implies velocities well into the tens of thousands of times the speed of light, if not hundreds of thousands.

Er, doesn't that say they went from taking hundreds of years to travel 4 light years to Alpha Centauri, to taking hours to do so? So that's about 2 LY/hour or more, or about 35,000c +.
On the topic of why context matters, I'll quote Cykeisme:
Cykeisme wrote:
Space Hulk fluff wrote: Whereas it once took centuries for human spacecraft to travel to Sol's closest neighboruing star, the same distance could suddenly be covered in just a few hours.
Hmm, the specific comparison used in the reference seems to indicate that they're referring very early applications of warp travel that were used on mankind's first interstellar voyage.
See, if it's only an improvement on a former FTL warp speed, then the real speed is not even as great as what andrewgpaul came to think of.





Connor MacLeod wrote: Page 5
The largest and most advanced human civilisation ever, the Imperium encompasses millions of stars and planets. Each human colony in this vast galactic realm is an island in a sea of emptiness, separated from its neighbors by thousands of light years of space.
Millions of stars and planets in the Imperium, with an average distance of thousands of light years between each world (which corresponds roughly to the velocities suggested above.)
Err... hello? Even at first glance, that distance number feels oddly high.
It is that each human colony --from your hive world, or quasi-hive, to any backwater swamp land-- is separated by at least 2000s LY. That actually makes a very low colonization density.

By world, we surely understand, on the average, a colonized world per system.

This means that if each world was represented by a disc with an incompressible radius of 1000 LY, with the world in its center, and that this center was equidistant to six other worlds located 2000 LY away (two disc radii), all of them also represented by their own same disc, and the first world's disc area touched the six other discs (see here, again), you could align a chain of 50 of such discs in a 100,000 LY long chain.

Well, the method is not rigorous, since the hexagonal packing above works from a chain with a diameter counted in an odd number of circles, but if you look at the number of discs in each ring (beyond the first circle in the center), and treat the ring number as n, you get 6n of them. This helps to establish an equation comprised of one simple series, +1.
What we'll do is see how many worlds we get at the 24th ring, and add half of those we'd get at the 25th ring.

Call the total number of worlds S. Using this calculator, I get:

S = 1 + sigma[1,24,6*k] + 3*25
S = 1876

So that's a grand total of 1876 of these "worlds", and that working from a 2000 LY wide spacing only. Considering that the galaxy is 1000 LY thick, there's not much room to wiggle around: pretty much all would be limited to a plane.
Here's a more automatized calculator if you want.

The key here could be the adjective average. We could say that 10% of the million worlds are 9,000 LY apart, and 90% of them 20 LY apart.
But there's a problem.
With a galaxy that's 100,000 LY wide, the circumference is only 314,160 LY. Even if you placed a couple of worlds on the most distant edge of the galactic rim, you couldn't cram enough of them as to have the few ones balance the clusters of packed worlds.
10% of a million is 100,000, and 10% of a million times 2000 LY is far more than the galactic circumference.

Unless I'm missing something here, this is an absolute lower end.





Connor MacLeod wrote: Page 5
Two points taht, in our reality, are tens of thousands of light years apart might be separated by a few miles in warp space.

....

Thus its possible for a suitably equipped ship to enter warp space through a warp gate, travel for a few hours, and re-emerge in our space millions of miles from the ship's departure point.
1. First point probably highlights how there is no definite correlation between real space and warp, or even consistency in the warp (since an Imperial warship could easily cover a few miles in a matter of seconds) - it goes without saying that this would imply insanely high FTL speeds (hundreds of millions if not billions times c.)

2. The second point probably means many billions/trillions of miles in reality, because "millions" of miles wouldn't even cover one AU, much less a light year. And probably highlights the far end of the scale for warp travel (ie a very slow one, because that velocity is positively sublight.)
1. Which is funny because I recall canon that says that the Warp/Aether/Immaterium rapes space-time physics, so it's rather funny to have a proportional distance measured in warp at all.
Or maybe I'm taking the fluff too... literally?

2. Since we don't know what the "...." were, it's hard to know if the second part exactly refers to the first one.







Connor MacLeod wrote: Page 5
Warp Space allows a spacecraft to travel hundreds of thousands of light years in only a few hours.
Hundreds of thousands o flight years in a few hours is between 580 million and 900 million times the speed of light.
Considering the many other references about lower FTL speeds, it's best understood as a theoretical top speed for the lucky craft that could rush down the fastest highway in hell. Read: extremely rare.
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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Fri Oct 23, 2009 1:41 am

Connor MacLeod wrote: Four separrate sourcecs this time, each a bunch of smaller quotes, but from a related source (Space Hulk basically._)

Space Hulk Rules 1st ed (if I recall the source correctly.)

Page 1
The Emperor of human space has recently become aware of the Stealer's activities and is taking immediate steps to isolate and stamp out the attack - but at a terrible price - the Emperor's Inquisitors ruthlessly sterilize tainted planets, wiping out their populations to the last man, woman, and child.

Though thus far 100% effective at stopping the spread of the Stealers beyond the infected planets, this solution is not without its drawbacks. In addition to the obvious loss of life and resources, if news of the scorched earth policy spreads, local governments may naturally become reticent about telling the Imperium they have been infiltrated.
It is mentioned here that the only reliable means of halting the genestealers is to sterilize a tainted planet. As mentioned in the "caves of ice" bombardment calcs, we can attach a very specific output to this level of firepower tens or hundreds of billions of megatons minimum, enough to boil/vaporize a planet's oceans and the like.

Of further interest is that such attacks also deprive the Imperium of access to the planet's resources (in addition to the loss of life.) As we know from BDZ estimates, resource destruction encompasses an energy input far in excecss of mere "extinction event" phenomena, and reinforces the extreme energies indicated by "sterilization".

We can also apply this figure to the BFG exterminatus calc (Capital ship being able to Exterimantus a planet in a matter of hours. From the bombardment calc mentioned before, we can figure on between e26 and e27 joules of energy for "sterilization", roughly. A light cruiser will be the smallest vessel qualifying as a capital ship. Therefore, for a light cruiser to "sterilize" a planet in a matter of "hours (2-23 hours). The sustained firepower for a light cruiser performing an exterminatus to sterilize a planet will fall somewhere between e21-e22 watts (nearly a day) and e23-e24 watts (2 hours). Or somewhere between (roughly) single digit and triple digit TT/sec.
Or perhaps those calculations are inaccurate, and that the Imperium, notably in the past, was known to use those virus bombs that turn people into goo that decayed into volatile gases, only waiting to be ignited.








Connor MacLeod wrote: Space hulk 2nd edtion missions book

Page 2
This proceess [Space Marine creation] takes many years and can only occur while the Space Marine is still growing,
Many years to field the Imperium's elite soldiers. Unless they can fast grow humans (perhaps, I don't know and wouldn't be surprised they can), it would require waiting for the equivalent of the age of 16 and beyond to get a sufficiently well shaped body.









Connor MacLeod wrote: PAge 4
Indeed, it is not unknown for a ship to drop back into real space before even setting out on its journey.
a well known phenomenon of the Warp involving time travel.
Proof that measuring distances in warp is highly unfeasible. This also adds to the list of issues about Warp travel. It seems that in general, every ship has experimented this phenomenom at least once.







Connor MacLeod wrote: Page 57
Melta bombs are target effect grenades that superheat the area and melt-down anything in contact with it.

...

When a melta-bomb is thrown the Marine player selects the target square and removes anything in it. A pitfall marker is then placed facedown in the square. The marker represents a mass of hot gases and molten metals and completely blocks LOS and movement.
This indicates that anything attacked by a meltabomb is melted/vaporized (like with a meltagun) - For something large (like a tank) this could easily be in the double or tirple digit GJ range.
By comparison, the "Davy crockett" nukes could vary between 10 tons and 1 kiloton in terms of yield (but weighed something like 35 kg, while melta bombs are quite a bit less bulky.)
Considering the existence of melta missiles (IE Ghostmaker) and other sources, man portable weapons comparable to small nuclear weapons are not uncommon.
And again no indication that the weilder needs to take cover or whatever. I suppose, in game terms, that the trooper can even throw that thing in the adjacent square. Hell, it's literally said, for melta-stick mines or something, that the soldier has to get into melee range to clamp the charge to the target.

The bomb may be throwable, but the energy needed to vaporize and melt any target is so mad that it cannot happen without exotism. You cannot cut it imho: if the bomb is easily portable and can be thrown, its energy density is formidable, and this can only be coupled to a powerful blast.
Yet blast effects are the most distinctively lacking effect.







Connor MacLeod wrote: Page 64
Eureka: a medium-sized planet in a system containing an amazingly rich asteroid belt. A planet that has been contaminated with a heavy Genestealer presence.

Action required: to obliterate the infection.

Solution: Extreme action required. Suggest we redirect ore asteroid to impact with the planet's surface.
The Space Marines deem it neccesary to wipe out a Genestealer infestation by dropping a big rock on the planet. A probable extinction level event.

Page 64
By jettisoning the tug itself, he could redirect the massive chunk of ore to impact onto Eureka's surface with the force of a hundred thousand fusion bombs. The resulting destabilisation of the planet's orbit, the atmospheric pollution, and the rapid onset of the greenhouse effect would destroy the Genestealer population totally.

If we go by modern nuclear weapons, (50-60 megatons) the total yield would be about 5 or 6 teratons of TNT. Enough to cause nasty effects, but hardly enough to meet exterminatus standards.

If we go by 40K standards (ie the 610 GT warhead from 122 5 gigaton bombs) we can work out that that the asteroid would hit with a force close to 500 TT, which is within the lower limit of the extinction threshold (But not guaranteed as a kill.) If we use the whole 610 GT figure, it goes to 61 petatons, which would be within the "sterilization" threshold I mentioned before.

If we work backwards and assume a 1 billion megaton minimum, by the way, we can infer that an Imperium "fusion bomb" is at least 10 gigatons. Plasma torpedoes, established in "Space Fleet" to be 1000x more powerful than conventional nuclear weapons (presumably including fusion bombs) would be in the 1-10 TT range, depending on what kind of "nuclear" reaction it referred to.

If we apply the 61 Petaton figure to exterminatus calcs from BFG (1 light cruiser over a 2-23 hour timeframe), we get a firepower yield of between 800 gigatons and 8.5 TT minimum for a light cruiser.
Of very little importance. The asteroid is going to do most of the damage, and the only thing that needs to be done is to kick it a bit so its own speed would now define an impact velocity.
The interesting bit here, though, is that the pollution and a greenhouse effect are deemed as necessary as the orbital knock to kill the Genestealers. They would not be cited if they were irrelevant.
I'd have expected the backbone of Tyranid forces to be more resilient to hostile environments.

As for the fusion bomb, if it were 100 MT a piece, the final destruction yield would be 10 teratons. More than enough to pollute a planet and generate a greenhouse effect that was deemed good enough to end the infestation.

There's also a problem that's been overlooked here: the planet's orbit was destabilized.






Connor MacLeod wrote: Page 64
"This vessel?" Denzark points to the scarlet line edging its way into geostationary orbit, high above Eureka's surface.

"That's the tug, sir. It isn't a ship as such, simply a fusion engine and crew quarters attached to the ore, which has been welded into one massive block. Its over 700 meters wide and 3 km long, and contains thousands of millions of tonnes."
This provides another potential way to calc the the energy level delivered by the impact, if we knew the velocity.

incidentally, assuming the fusion engine provided a 3 gee acceleration for the mass given (2 billion tons), the engine would require a constant output of 1.6e22 watts. If we go with 300 gees, the output goes up to 1.6e24 watts. "billions of tons" would probably be well into the battlecruiser/battleship range of mass, incidentally.

If you wonder why I say that even though its got the volume (roughly) of a heavy cruiser - a heavy cruiser isn't a 100% solid lump of metal. Although if it was 90% empty (a reasonable assumption for a ship) we can infer a IoM cruiser masses in the tens or hundreds of millions of tons.
First off, if that ship was a brick 3000 x 700², it would have a volume of 1.47 e9 m³. Since there's billions of tonnes of ore, at least the bulk density of that whole thing doesn't seem totally borked.

Now, as for acceleration, the kinetic energy that is gained each second, under that constant acceleration, is not 1.6 e22 J.
Thousands (e3) millions (e6) of tonnes (e3 kg) makes n e12 kg.
With 2 e12 kg, and 3g, the correct value is 864.36 e12 W, or 206.587 kilotons/s.
At 30g (294m/s²), that looks like a generous acceleration for a tug, that's a hundred times the power above (20.6 MT/s).

In case of an acceleration of 300 g (2,940 m/s², totally absurd), the kinetic enegy gained per second is 8.644 e18 J, or 2.066 gigatons.

Now, let's look at the final velocity. We know the ship and its ore are located in geostarionary orbit.
For Earth, the GEO is located at 36,000 km above the equator's surface. The planet Eureka is medium sized, which means it would probably be under Uranian size, so perhaps a bit bigger than Earth, or less. Let's consider it's a tad bigger.
If we assume a geostationary orbit of 40,000 km and a linear acceleration, and that it hit at 90° against the surface...
Trip durations are obtained from the series for both 29.4 m/s² and 294 m/s², in order to cover 40,000 km.

At 3g, trip duration is 1649 seconds. Impact velocity: 48,480.6 m/s ; Maximum possible KE = 2.3504 e21 J.
At 30g, trip duration is 521 seconds. Impact velocity: 153,174 m/s ; Maximum possible KE = 2.3462 e22 J.

It goes without saying that there is no proof that the ship could provide a constant acceleration, but it gives an idea of the level of damage to expect.
It's also unreasonable to imagine that the tug ship has that much fuel to burn to move its own ore at such speed.

561 GT/5.6 TT...

Could that be enough to budge the planet? What does it take to budge a planet out of orbit, really?
Since Eureka is medium-sized planet, we're obviously above what counts as just above a planetoid, but we're not nearing a gas giant either, so let's pick Earth, and let's play with this impact simulator.

I picked a projectile diameter of 3000 m, a density of 10 tons per cubic meter, both impact speeds as obtained above, with an angle of 90° (straight up).
It's a smash into sedimentary rock.

Results:

Code: Select all

Your Inputs:
    Distance from Impact: 1.00 km = 0.62 miles 
    Projectile Diameter: 3000.00 m = 9840.00 ft = 1.86 miles 
    Projectile Density: 10000 kg/m³ 
    Impact Velocity: 48480.60 km/s = 30106.45 miles/s (Your chosen velocity is higher than the maximum for an object orbiting the sun)
    Impact Angle: 90 degrees 
    Target Density: 2500 kg/m³
    Target Type: Sedimentary Rock 

Energy:
    Energy before atmospheric entry: 1.66 x 10^29 Joules = 3.97 x 10^13 MegaTons TNT
    The average interval between impacts of this size is longer than the Earth's age.
    Such impacts could only occur during the accumulation of the Earth, between 4.5 and 4 billion years ago.

Major Global Changes:
    The Earth is not strongly disturbed by the impact and loses negligible mass.
    The impact does not make a noticeable change in the Earth's rotation period or the tilt of its axis.
    The impact does not shift the Earth's orbit noticeably.

Crater Dimensions:
    Transient Crater Diameter: 1380 km = 860 miles
    Transient Crater Depth: 490 km = 304 miles

    Final Crater Diameter: 3570 km = 2210 miles
    Final Crater Depth: 3.47 km = 2.16 miles

    The final crater is replaced by a large, circular melt province.
    The volume of the target melted or vaporized is 1.48e+09 km³ = 3.54e+08 miles³ 
    Melt volume = 4.25 times the crater volume 
    At this size, the crater forms in its own melt pool.

Code: Select all

Your Inputs:
    Distance from Impact: 1.00 km = 0.62 miles 
    Projectile Diameter: 3000.00 m = 9840.00 ft = 1.86 miles 
    Projectile Density: 10000 kg/m³ 
    Impact Velocity: 153174.00 km/s = 95121.05 miles/s (Your chosen velocity is higher than the maximum for an object orbiting the sun)
    Impact Angle: 90 degrees 
    Target Density: 2500 kg/m³ 
    Target Type: Sedimentary Rock 

Energy:
    Energy before atmospheric entry: -NaN x 10-NaN Joules = 3.96 x 10^14 MegaTons TNT
    The average interval between impacts of this size is longer than the Earth's age.
    Such impacts could only occur during the accumulation of the Earth, between 4.5 and 4 billion years ago.

Major Global Changes:
    The Earth is not strongly disturbed by the impact and loses negligible mass.
    1.34 percent of the Earth is melted 
    The impact does not make a noticeable change in the Earth's rotation period or the tilt of its axis.
    The impact does not shift the Earth's orbit noticeably.

Crater Dimensions:
    Transient Crater Diameter: 2300 km = 1430 miles
    Transient Crater Depth: 812 km = 504 miles

    Final Crater Diameter: 6320 km = 3920 miles
    Final Crater Depth: 4.12 km = 2.56 miles

    The final crater is replaced by a large, circular melt province.
    The volume of the target melted or vaporized is 1.47e+10 km³ = 3.54e+09 miles³
    Melt volume = 9.3 times the crater volume 
    At this size, the crater forms in its own melt pool.
In both cases, read:

The Earth is not strongly disturbed by the impact and loses negligible mass.
The impact does not make a noticeable change in the Earth's rotation period or the tilt of its axis.
The impact does not shift the Earth's orbit noticeably.

Note: it is unclear if the calculator can be used for such high values. But if we were to admit its method to calculate orbital shift is based on the momentum and energy, chances are that it may be reliable.
In such case, we could then say that the orbital break from the book would be scientifically wrong, and could not really be taken at face value, unless considered extremely negligible and just mentioned for the fact that *something* did happen.

All in all, we're pretty far from the claims made by Connor, especially since the extremely generous parameters used for the calculator (3 km wide sphere, density of 10 tons/m³).

Finally, remember the part about redirecting "the massive chunk of ore to impact onto Eureka's surface with the force of a hundred thousand fusion bombs."

That's 1 e5 fusion bombs. Now the values I got were 561 GT and 5.6 TT. That's respectively 5.61 MT and 56.1 MT a piece, for your fusion bombs.
Let's not forget that these values are based on the maximum KE possible. Since the ship may not have the equivalent of hundreds or thousands of gigatons of fuel in stock, the yield of a fusion bomb could be anywhere between low megaton or kiloton range.





Connor MacLeod wrote: Page 4
Though not extensive it encompasses a region of space some three hundred light years in diameter, with the Tau home world at its centre, ,and nearly a hundred settled worlds.
Scope and size of the Tau Empire (at least circa the 2001 Codex.)
Interesting. That would be a disc with a surface area of 70,686 LY².

If we pick 99 settled worlds, that's a maximum of 1.4 e-3 settled worlds/LY².

Over the whole galaxy (100,000 LY wide), assuming all of its space was evenly peppered with worlds and no void, we would have a SA of 7.854 e9 LY², and therefore 10,995,600 settled worlds.
Almost 11 millions.
I'm not sure where I'm going with that, safe perhaps that the Tau Empire may be more densely packed than the Imperium, since we know that the Imperium doesn't cover the whole galaxy, and that the galaxy is not a mono compact volume of worlds.

If treated as a sphere, the volume is 1.4137 e7 LY³. It's 1.4137 e5 LY³ per world, or 7.073 e-6 worlds/LY³.

That said, let's not be fooled by the number. A galaxy is all but a disc full of worlds to conquer. There's a large amount of void between each arm, and the real meat and potatoes is found around the core.
One day, we'll get there!





Connor MacLeod wrote: Page 10
The Tau empire encompasses a dense yet astrographically small area of space. Many hundreds of star systems exist within this region, and an unusually high proportion harbour an environment conducive to life. As the Tau steadily expand the borders of their empire, they continue to encounter other races. The Empire now encompasses over twenty septs, - fully developed Tau homeworlds. The populations of these worlds are fully integrated in to the empire, each striving towards the Greater Good.
There are at (least?) twenty Tau "septs" or homeworlds, with probably as many (if not several times more) colonial ones, plus all their member worlds.

Also, the region holding the Tau Empire is considered "dense yet small" and encompasses "hundreds" of Star systems. This suggests the Tau have yet to completely explore/occupy the region (since as noted before they don't seem to have more than a hundred or so worlds.)
Or that there are systems with worlds which don't offer the necessary requirements for proper settlement.
Interestingly, the fact that the Empire is located in a dense area of space fits with the stuff from above.
Last edited by Mr. Oragahn on Thu May 06, 2010 9:35 pm, edited 2 times in total.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Fri Oct 23, 2009 8:22 pm

Page 8, mere talk about Tau tactics and FTL drives.
Skip to page 9.






Connor MacLeod wrote: Page 14
"One of their light walkers carried a weapon of lethal effect. It fired a form of ultra-high velocity projectile. I saw one of our tanks after having been hit by it. There was a small hole punched in either flank - one the projectile's entry point, the other its exist. The tiny munition had passed through the vehicle with such speed that everrything within the hull not welded down had been sucked out through the exit hole. Including the crew. We never identified their bodies, for all that remained of them was a red stain upon the ground, extending some twenty metres from the wreck.
Effect of a TAu railgun weapon. I think that there might be some hyperbole taken with this, given that I don't think its possible for that to be true, and I'm not sure the obsever could actually tell what happened inside, unless massive amount of pulverization to a fine mist (or outright vaporization) occured.

If by "walker" this means some Tau battlesuit, its probably the Broadside battlesuit, which masses some 3.8 tons (as per IA3) Assuming they brace the suit before firing (they're not very mobile, we might infer between 3800-7800 kg*m/s worth of momentum (approximately) Since we know Tau railguns are hypervelocity/hypersonic, we can infer a minimum velocity of around 2-3 km/s (rougly.) Which might suggest a minimum projectile mass of 2-4 kg (roughly). The KE would be roughly half that of a tank round to several times that, depending on the actual mass/velocity combination (2 kg at 2 km/s is around 4 MJ, while 3 kg at 3 km/s is roughly 13-14 MJ). But that is, IMHO consevative, because we dont know how they may or may not compesnate for recoil.

Going by scaling of the railgusn on the broadside suit, they appear to be roughly 100-120 mm in diameter. Assuming the projectile is cylindrical and its length is twice its width (so about 20-25 cm) and iron composition, the mass of the round would be between 10-12 kg (100 mm) or 20-22 kg (120 mm). Assuming the same 2-3 km/s velocity minimum, the KE would be between 20 MJ (100 mm at 2 km/s) and 100 MJ (120mm at 3 km/s). Momentum would be 20,000 kg*m/s and 66,000 kg*m/s.

Note, however, that as far as impacts go, hypervelocity impacts can be a bit different than the lower velocity ones we might associate with a battle cannon. In this case,
KE probably isn't as important to penetration as force/momentum is due to the "shoot-rhough" both sides of the tank with little apparent loss in velocity. And if the projectile doesn't slow down (the hull doesn't resist it), not all the energy will be transferred to the hull, and thus won't melt/vaporize its way through the hull. SOME heating would invariably occur, however, so we can imagine it would help penetration some, at least. Cross section of the round (especially at the tip) will also affect penetration (particularily in terms of force/pressure.) and this may offset any difference in momentum between a railgun shell and a batlte cannon shell.

Also, we dont know for sure what kind of tank it is, whether it was undamaged or had sustained previous injury, or what.
Not only the description really fails to make much sense, but it's good to notice that the Tau would probably prefer a narrow but longer projectile for their railgun, than one that is 10 to 12 cm wide.
The width of the cannon could be related to recoil systems more than the caliber of the weapon.
Here's the Tau XV88 Broadside Battlesuit:
http://wh40k.lexicanum.com/wiki/File:Br ... lesuit.jpg
I must say that the position of the cannon is particularly shitty. That whole dandling thing behind each arm is also certainly not going to help compensating for the angular momentum.

Stupid mecha design. :p








Noble713 wrote: I did a search for "Hive world Minea" with no results, so this stuff apparently hasn't been covered. It's from the 5th edition rulebook, and a thread on misc numbers seemed the best place to put it. It's take from a graphic/data readout.
pg.115
Minea
ha class Hive World, Ultima Segmentum
Population: 154 billion
Approx. number of hive worlds in the Imperium: 3.238 x 10^4
Imperial Garrison Strength: 2,000,000 men
Planetary draft: 1,249,000 per annum
This states that there are approximately 32,380 hive worlds in the Imperium. If Minea can be taken as an average/typical hive world, then these worlds supply 40.4 billion troops every year.

If we assume a population growth rate of 0.5% (reasonable, given the precarious resource situation of most hive worlds) for Minea, there should be ~770 million people reaching adulthood annually on this world, so only about 0.16% of them are being drafted. Note that this is close to the US Army's rate of volunteer enlistment for 2006 & 2007 (link).

The closest thing the real world has to Cadia is North Korea, the most heavily militarized country in the world with 20% of it's military-age men under arms. From a manpower perspective, the Imperium should be able to support a military several orders of magnitude larger than what we see here. Clearly their constraints are of a logistical nature (not enough lasguns to go around? :) ).
pg.117 (galaxy map)
Macragge
Population: 400,000,000
If the conscription rate of the capital of Ultramar (which we know supplies regiments to the Guard) is the same as Minea's, Macragge would supply 3.2 million men annually.
Huh, that complicates things.
I didn't picture tens of thousands of hive worlds. With that many, things get very different from my initial estimations.
Clearly, the billions from the introduction of some of the Cain books and 5th edition rulebook either has to be reinterpreted, or Minea represents an exceptional hiveworld.
Option 2, however, doesn't work.

The billions from the Cain books may have to refer to the military personnel, and therefore we could safely assume many trillions for the whole population. 32380 hive worlds, even with populations like of Isstvan II (12 billions, but there may have been survivors under the surface) would bring represent 388.560 trillion people. The right number may even literally tickle the quadrillion range, if worlds like Minea and other hiveworlds from the Gothic Sector represent a good chunk of the whole hive world group. The higher end would clearly trample the quadrillion range easily.







There's actually a couple of references from a Rogue Trader book I have to drop there.
First and foremost... so many of the designs really sucked hard back then! On the plus side, the Eldar war-walker was really neat.
It's also an universe that seemed to take itself less seriously. Commissars with sunglasses, Orks with baseball caps, and plenty of colours (there's even a traitor robot, affiliated to Slaanesh, that's pink and green)... the 80s.

That said, let's take a look at some bits picked from the the book that are interesting.
Again, the source is the quite old Compendium:
WD's Rogue Traders: Compendium, p. 15 wrote: A hive-world gang stood about 6 metres away, las-pistols in hand, taunting him.
...
The rest of the gang leapt forward - six were dead before they landed. The storm bolter's barrel begain to glow as Tirus pumped shot after shot into the enemy. The men seemed to dance as each shell exploded beneath their skins, opening up pink craters across their bodies and filling the air with a red mist.
That also works as vaporization. "A storm bolter is basically two bolters firing in unison."
They are heavy weapons.
WD's Rogue Traders: Compendium, p. 32 wrote: It had once been an arm. The melta-blast had fused metal, flesh and bone into a twisted mass; weapon, armour and arm were indistinguishable. The bolter's magazine had exploded under the intense heat, showering the Marine with shrapnel. There might yet be hope, though.
The melta has not wholly incinerated the poor man, and the bolter's magazine didn't spread him across the battlefield as it exploded.
Seems the weapons were tamer back then.

Talking about the machines as a whole, all species cofounded:
WD's Rogue Traders: Compendium, p. 57 wrote: Dreadnought Construction

The powerplant that lies at the heart of each Dreadnought may be a crystal battery, a nuclear engine, a polarising gravitic bed, or a conventional combustion engines. The actual technology used is not strictly important except, of course, in terms of refuelling and supply. Crystal batteries are commonly used by Humans and Eldar, whilst Ork machines normally employ combustion engines. The dark smoke given off by these engines has inspired Humans to give Ork Dreanoughts the nickname of 'boiler'.
Considering that an Ork Dreadnought is not absolutely overpowered by a human Dreadnought, obviously the likely cumbersome combustion engine would be much greater in size than the nuclear engine used in other machines, or the crystals, but not necessarily much less powerful.

One of the three Imperial Battle Armours was the Furibundus-class destroyer dreadnought (perhaps this what inspired Curtis Saxton's bizarre nomenclature). It had both crystal fuel and combustion fuel manifold/exhaust.
WD's Rogue Traders: Compendium, p. wrote: The shell of the Dreadnought is made from tough ceramite mouldings. Some Ork Dreadnoughts are built from metals, but these tend to be ridiculously heavy and cumbersome. Ceramite begins life as a thing white liguid which is injected into moulds under pressure. The mould is gradually heated to 300° and then allowed to cool. The moulding is the both tough and durable.
The process of crafting a ceramite shell.
WD's Rogue Traders: Compendium, p. wrote: Imperial and Eldar Dreadnoughts are further protected by armoured plates from adammantium. This material is produced in the processing factories in orbit around Mars as well as on Eldar craft-worlds. Each wheel-shaped factory consists of a vast spinning centrifuge several kilometers across. The inside of the rim is maintained at a constantly high temperature by plasma held in place by magnetic fields. Only under these conditions is it possible to melt adamantium so that it flows into moulding chambers built on the outside of the factory rim.
The properties of adamantium and its industrial use.
Chaplains armours were also composed of adamantium.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Jedi Master Spock » Fri Oct 23, 2009 8:36 pm

Mr. Oragahn wrote:
Noble713 wrote:
pg.117 (galaxy map)
Macragge
Population: 400,000,000
If the conscription rate of the capital of Ultramar (which we know supplies regiments to the Guard) is the same as Minea's, Macragge would supply 3.2 million men annually.
Huh, that complicates things.
I didn't picture tens of thousands of hive worlds. With that many, things get very different from my initial estimations.
One hot minute, please. Is the above a typo, or did Noble713 make a three-order-of-magnitude error, or am I missing some strange assumption? 400 million would give an annual tithe of 3200 at the same percentage rate as 154 billion tithing 1.2 million.

Lexicanum does also list 400 million as the population.

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Re: WH40K - 40K misc numbers... (SDN)

Post by Mr. Oragahn » Fri Oct 23, 2009 8:43 pm

Thinking of it, I should have probably put the extra Rogue Trader references in the 1st/2nd edition thread.

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