Next installment, plus the long-awaited multimelta calc (revised edition). In fact this one is very calc/number heavy, so be sure to pay attention.
Page 21
The adept sighed, and his organic eye flickered behind a pale lid as information relayed from the multitude of surveyors and augurs positioned around the spaceport flooded his senses through the technology of his mechadendrites.
direct neural link wiht the sensory data around the spaceport.
Page 22
- Mention of orbital augurs (sensor platforms.)
Page 22
Where there hsould have been washes of energy sweeping down from the mountains, there was only black emptiness. The surveyor stations on the nothern slopes were silent, their auguries no longer active.
- again sensors indicative of active sensing.
Page 22
Nothing should be able to enter even the outer edges of the system without them being aware of it... could it?
...
No, the logic engines would have screamed the place down many days ago if it had detected this size of fleet approaching. Somehow these starships had avoided detection by some of the rarest and most precious equipment available to the Adeptus Mechanicus.
The implication of some FTL detection (passive) to detect the arrival/presence of a large fleet. It also indicates that it would take said fleet "days" to reach the planet. That would generally be suggestive of accelerations on the
tens or hundreds of gees range. Then again its bound to contain transports as well as warships, so it could be the warships are constrained by the speed of the slower ships.
Page 24
Others smashed into runways, cratering them and melting the honeycombed adamantium with the heat of a star.
Magma bombs launched by a Iron Warriors battle barge above. "heat of a star" taken literally
might infer mid to high gigaton/low teraton range warheads, (note the italics, because this isn't certain) but not much larger, because the yields would be well into extinction level. Hell, at the yields as it is, they probably could inflict significant global effects as it is. (Though Hydra Cordatus was already subject to extinction level firepower before, so its not exactly "habitable" to begin with..)
Page 29
Behind four linked and high-walled berms, Honsou could see the aerials of tanks, but what pattern they were he could not yet tell.
The "berms" (which are partt of the bunker complex) are as tall/taller than a Russ. Also note that the Jourans also have tanks as well as artillery.
Page 30
Armoured bunkers at each of the compass points sprayed the area in front of the tower with deadly bullets.
The aforementioend "armoured bunkers". Given the bunkers earlier that Honsou described as well as what is indicated, they seem to be at least 3-4 meters tall.
Assuming a boxlike formation, we can infer the dimensions roughl. By referring
here we can approximate thickness of real life military bunkers.
Page 31
"I want you to put enough melta fire into that bunker to make the rock run like liquid."
Melta gun (well rather multimelta) intended to "melt rock", indicating the bunker composition.
Page 31
Bolt after bolt of powerful las-blasts slammed into the protruding salient angle of the bunker, blasting away huge chunks of armaplas and rockcrete.
...
The two Iron Warriors paid no attention to the incoming fire, sending shot after shot of unimaginably powerful energy into their target. Honsou watched as the angled corner of the bunker cracked wide open, the rockcrete burning orange in the heat.
Indication of just how durable rockcrete bunkers are, to withstand multiple bursts of lascannon fire before only "glowing orange." (at least four shots.)
IF we assume the corner busted open was about a metre wide (about wide enough to let a melta beam through, as well as about what the thickness of the wall was). We know already the bunkers were abount 3-4 meters tall. Thickness is a bit more difficult to approximate, but by browsing
this site on pillboxes, which is a kind of bunker, we might infer between .3 meters and a full meter in thickness. Assuming density and thermal properties of silicon (given that its mentioend to be"rock"), the mass of rock affected would be between 2,000 and 9,400 kilograms.
Temperature-wise, "orange" generally means a temp of around 1000-1200C (~1300-1500 K) in
lava, which will suit our purposes here. Silicon by itself has a specific heat of around 700 j/kg*K. (Note that this can vary according to the kinds of material. Granite has a specific heat of around 800 kj/kg*K, while SiO2, used in BDZ estimtes, has a specific heat of around 1050 J. Rockcrete, used in the bunkers, probably is not "pure" silicon, but one of the others. I will include Silicon for conservatism's sake.)
Taking all the variables into account, the energy input can be between
1.4 GJ (for silicon at 1300K, with the 2000 kg figure) up to
12 GJ (for SiO2 at 1500K with the 9400 kg figure) as a low end. Unofrtunatley, we dont kwo the exact number of lascannon shots (implied to be at least four, but not sure how many more beyond that.) Probably not a huge number, given that lascannon are not "large shot capacity" weapons in a man-portable version and they didn't reload. Nonetheless we can conservatively decide tht they are
high triple digit MJ to low GJ range, which would be consistent with the performance of other "anti-armour" weapons such as meltas as well as certian other observed instancecs of lascannon. My bet would put it in the singel digit GJ range, at least.
PAge 31
Before the echoes had died, the Iron Warrior with the multi-melta rose from his concealment and charged forwards to fire. The guns' discharge built to a deafening screech before erupting from the barrels in a searing hiss. The warrior's aim was true and the air inside the bunker ignited with atomic fury, spurts of vaporised flesh and superheated oxygen blasting from the weapons slits.
Meltablast vaporizes the troops inside and, as noted before and later, melts the bunker itself to liquid. We have no idea how many troops were inside, but if they had at least a squad (possible) and vaporized them all, it could be easily several gigajoules minimum. More if incineration was involved (which is likely, discussed below)
It is curious to note, ,however, that the wepaons' effects seems to imply a more "explosive/area effect" weapon, as I noted long ago. This is, of course grossly conservative and I'll cover the other effects below.
Page 32
He leapt over the Marauder's fuselage and sprinted towards the molten hell of the destroyed bunker, its walls now flowing like wax across the ground.
...
Honsou leapt onto the remains of the bunker, his ironshod boot sinking into the molten rock.
Again, note fo the composition and result of the meltablast to the bunker. Assuming a 3-4 meter tall bunker like a box, with half meter thick walls, it totally masses some
57,000 to 111,000 kilograms. Assuming rocklike properties as above, you can figure ~2-2.5 MJ per kg to melt. Roughly, you'll get between
120 GJ and 280 GJ minimum from all that, but if the walls are thicker (say a meter thick) you can get
~330-420 Gigajoules.
Even then,it doesnt factor in inefficiencies or even the fact its probably indirectly melting the bunker, or that the bunker in question could be much larger. For example, if we assume the bunker was 6 meters square but 4 meteres tall, with metre thick walls, the area affected could be well over
260,000 kg, which could output between 500-650 Gigajoules to melt.
The end result remains that the multi-melta is firmly in the triple digit gigajoule range, at the very least.
Page 32
Scorched and blackened limbs lay strewn about, all that remained of those stationed too close to the bunker; the backwash of the melta impact had burned flesh and bone to cinders in an instant.
As noted above, vaporizationw as conservative, as multiple Guardsmen are mentioned to have been incinerated as a mere side effect. The aforementioned squad being incinerated (in the bunker) would yield around
10-30 gigajoules depending on efficiencies. Assuming a man-size target (about 1-3 GJ to incinerate.) standing a few metres away could easily require between
50-70 gigajoules minimum up to several huundred gigajoules, which would be consistent with the "bunker melting" incident.
Page 32
Another white-hot blast of melta fire flashed and the Demolisher's turret was engulfed in the inferno of the impact. Steam and smoke obscured the tank for brief seconds, but unbelievably, it continued onwards through the boiling cloud.
Time slowed as Honsou watched the barrel of its main gun depress and knew that any second it would blast him to atoms.
...
Honsou roared in release as he realised the heat of the melta blast must have warped the barrel enough to cause the weapon to misfire and the shell to detonate prematurely.
Melta blast of aforementioned yield onyl cause minor damage (yet sufficient to cause gun to backfire, merely indicating that location is important.) to the tank. Indicative of extreme thermal toughness of Imperial Guard tanks.
Assuming "blast to atoms" means vaporize (literally might suggest somthing more akin to ionizing to plasma) and assuming a 500-1000 kg mass for Honsou would suggest the Demolisher shell was at least
a couple gigajoules. This may not hav been purely thermal energy, however, given what we know fo demolisher shells (a kind of shaped charge, actually.) and it is a gross lower limit nonetheless. It also ignores most of that mass is going to be iron, which could easily increase the calc several times (IE
5-7 GJ, minimum, assuming iron composition for SM armour)
Page 33
Kroeger's blood-maddened berserkers clambered across the shattered walls of the redoubt, ignoring wounds that would have felled a normal human a dozen times over.
CSM berserkers (KhornateS) Are at least a dozen times tougher than a normal human. Not sure if this means anything for regular CSMs or even regular Space Marines, though.
Page 38
"I've set the power to maximum to give us a chance of actually hurting one of these heretics, so you'll only get three, maybe four shots at the most.
Las pistols like lasguns can have variable settings. It is interesting to note that at the highest setting the weapon basically only has a couple shots. Assuming ~20 and 30 shots (as hinted at in the Inquisitor entry on lasguns), we can infer that a max power burst is between
5 and 10 times more powerful than the lower setting What's more, depending on how the power usage scales, this does imply many more settings than the mere "two" mentioned in other sources like the Uplifting primer. (If the power output doubles from the pervious shot as the Ghosts novels and the Triplex lasgun in the Inquisitor rulebook indicate), we could infer
roughly 4-5 different power settings.)
Page 39
The technicain fired a heartbeat later and Kroeger rocked back on his heels as the impact blasted a crater in his power armour. Before the Imperial could shoot again, Kroeger was upon him, backhanding his fist across his face and decapitating him in an explosion of blood and bone.
We have no idea how "big" a crater was made, but if we assume the armour is at least two inches thick, and assume 4 cm of penetration (80% of the way through the thickness), the crater diameter could arguably be 8 centimetrs assuming a roughly hemispherical hole. Assuming silicon and vaporization, it would take roughly
4.16 MJ to accomplish. Even assuming only one inch penetration, you could expect at least a megajoule. This all still disregards inefficiencies, and inferring from the "max output" above, we could conclude the "standard" or "low" settings (the 20-30 shots per pack one) as being in the
hundreds of kilojoule range.
The other calcable incident here is Kroeger's ability to cross the room before the person can fire. Average human reflexes are about a quarter of a second, either way (a fifth or a third, basically). A person firing a semi-autoatic weapon like apistol can reasonably thus expect to fire 3-4 shots in a second (not factoring in aiming.) Unfortunatley, we don't know the "size" of the room. From the (admittedly vague) passages concerning the command center, it was arguably quite large (more than enough for at least a handful of people), so a 10 meter width seems a reasonable assumption, though even at the lowest 4-5 meters would be possible (if crowded.) Assuming 1/3 to 1/4th of a second and 10 metres, Kroeger would have to be moving at
30-40 m/s to cross the room before the man fires again. Even at 4-5 meter distance, he'd have to be moving at 12-20 m/s.[/b] Frankly, I'm not quite sure the higher end is remotely possible, save by making leaping bounds, but while pushing crediblity, it may not be impossible.
Even assuming the person was particularily slow (say half a second) Kroeger would still have had to cross a couple meters. This is still 2-3x faster than a normal person from a standing start (5-10 m/s)
) 
