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Asherian Command wrote:Why not just ask the GW Customer Service the question How much damage does an Imperial Cruiser do?

Ask not the GW Rep a question. For he shall give you 3 answers, all of which are contradictory in nature.

Grey Templar wrote:
Ask not the GW Rep a question. For he shall give you 3 answers, all of which are contradictory in nature.

sigged

IvanTih wrote:It's not my fault(firepower thing),ask most people on StarDestroyer and SpaceBattles and they'll give same statements(less or more) as I.
Only way to be sure.

You're kidding right? You're the one posting stats that don't make any sense. Why don't you ask them, instead of putting the burden of proof on others when they point out the flaws in your argument. Try doing your own analysis instead of blindly regurgitating someone else's work.

keezus wrote:

IvanTih wrote:It's not my fault(firepower thing),ask most people on StarDestroyer and SpaceBattles and they'll give same statements(less or more) as I.
Only way to be sure.

You're kidding right? You're the one posting stats that don't make any sense. Why don't you ask them, instead of putting the burden of proof on others when they point out the flaws in your argument. Try doing your own analysis instead of blindly regurgitating someone else's work.

I asked them.
http://bbs.stardestroyer.net/viewtopic.php?f=4&t=144191 Connor
http://forums.spacebattles.com/showthread.php?p=5194741#post5194741 Another version of calcs

well if the necrons fully awoke, they could.

if all orks banded together in a big waggh they could

About 40k STL speed.
In flight of the Eisenstein they were accelerating to reach Holy Terra to inform the Emperor of Horus' treachery. Also when the Eisenstein is found by the Imperial Fists they came out of the Warp 4 light minutes from the Eisenstein, which Garro noted was little time to prepare for their arrival. Later a Black ship matches speed with them after they clear Neptune, while at .75c. All of which implies fairly high acceleration.
Then again we have 0.75 from Sabbath Matyr.
Remember that Rogue Trader contradicts itself(we have freighter travelling at 3000 km/s while we also have single digit G,blame Andy Chambers who also gives them single digit in Rogue Trader novels).

On anything v.s. Roks: Can't we just put it down to wacky Ork psychic powers making the Rok significantly more durable than asteroids?

@Ivan: From what I can glean from those links, there appears to be no consensus on power level based on the nova cannon effects as described by the fiction - only a range is produced. Considering that this range encompasses several magnitudes, I would think that the upper limits are very suspect - especially considering the outright stated yield of 610GT for the torpedoes.

I have no intention of joining SD forum (wretched hive of scum and villainy and all that... ) - would you be so good as to ask about the issue with the huge spread in weapon powers on ship mounted platforms? The current spread per this thread is 10^3-10^5. The supporting fiction indicates that these weapons are all employed against the same targets. Applying common sense: Three scenarios develop: Either the huge spread is wrong, and the actual spread in power between ordinance/lances/novacannon/torpedoes is a much smaller magnitude (10x to 100x), OR the weakest weapons -are- ineffective, OR the bigger weapons would be one-shot killing the intended targets.

My choice would be no. 1, as the fiction doesn't seem to support the last two of the three scenarios. I'd be interested to see what your experts think about this.

Has anyone mentioned Homeworld yet? I wonder how those ships would fare against the Imperial Navy, particular the Progenitor vessels

The Sajuuk is probably the only one to stand a chance, due to its supreme mobility and firepower.

i think not i was playing with my friend (first time she has played) i be nice and let her use my beloved marines... first turn she has killed half of my tau force
by the end of the game the only dead marines are 2 bikers that her librarian accidentaly killed when the attack scattered
so in conclusion IOM 4 eva

Blood Raven 5th Company wrote:i think not i was playing with my friend (first time she has played) i be nice and let her use my beloved marines... first turn she has killed half of my tau force
by the end of the game the only dead marines are 2 bikers that her librarian accidentaly killed when the attack scattered
so in conclusion IOM 4 eva

For starters, some grammer and puncutation would be nice.
Thats just plain bad luck, we play a game where dice determine the results, its just down to luck really and you just had some bad luck thats all.

keezus wrote:@Ivan: From what I can glean from those links, there appears to be no consensus on power level based on the nova cannon effects as described by the fiction - only a range is produced. Considering that this range encompasses several magnitudes, I would think that the upper limits are very suspect - especially considering the outright stated yield of 610GT for the torpedoes.

I have no intention of joining SD forum (wretched hive of scum and villainy and all that... ) - would you be so good as to ask about the issue with the huge spread in weapon powers on ship mounted platforms? The current spread per this thread is 10^3-10^5. The supporting fiction indicates that these weapons are all employed against the same targets. Applying common sense: Three scenarios develop: Either the huge spread is wrong, and the actual spread in power between ordinance/lances/novacannon/torpedoes is a much smaller magnitude (10x to 100x), OR the weakest weapons -are- ineffective, OR the bigger weapons would be one-shot killing the intended targets.

My choice would be no. 1, as the fiction doesn't seem to support the last two of the three scenarios. I'd be interested to see what your experts think about this.

There's no 22 petatons,new calcs.Such a weapon would require a reactor capable of at least 1.54e21 watts to power it(new calc Nova cannon),2% isn't close to lightspeed if you're an idiot.
http://bbs.stardestroyer.net/viewtopic.php?t=33022

Using HDS' fifty meter apature quote, I decided to do some low end calcs on the KE of a nova cannon warhead. If we assume that it's a fifty meter cube (I know that's a rather unlikely shape, but bear with me) made of solid iron. (Again rather unlikely, but I would imagine that the shell is much longer than its width.) Now, taking the quote about the speed things are fired from a bombardment cannon (Nearly 1/4 C) found in Excecution Hour and the quote in the BFG rulebook that states a nova cannon firing at 'close to' C, I will take 1/4 C as a low end velocity.

Volume of Shell : 125000 M^3
Density of Iorn : 7874 kg/m3
Mass of Shell : 984250000 Kg.
1/4 C : 75000000 M/s

KE of Shell : 2.768203125 e+24 J(I do love such useful ready reckoners.)

2.768203125e+24 joule = 661,616,425.669216 megaton [explosive]

This says a lot about the energy capabilities of Imperium Ships, specifically the Graviometric Impellers, and about their materials strength, given that they can withstand this recoil (Admittedly only along their forward axis) Unfortunately the weapon is a standoff blast, so this isn't the energy delivered to the target.

Now, to try and find an image or description of the shells in more deatil.

NB, I'm not going to bother trying to factor reletavistic mass increase here, lets leave it Newtonian for a while shall we?

Then we have bombardment cannon calcs.
http://forums.spacebattles.com/showthread.php?t=94376
Also Star Destroyer isn't that evil.I have met many polite members there.Mike Wong isn't active there since May.

Commissar Agro wrote:

Blood Raven 5th Company wrote:i think not i was playing with my friend (first time she has played) i be nice and let her use my beloved marines... first turn she has killed half of my tau force
by the end of the game the only dead marines are 2 bikers that her librarian accidentaly killed when the attack scattered
so in conclusion IOM 4 eva

For starters, some grammer and puncutation would be nice.
Thats just plain bad luck, we play a game where dice determine the results, its just down to luck really and you just had some bad luck thats all.

Is this better for you. (nah ive never been good at english ( last semester 4 our sci fi story i was told that i just got the sci fi part down pat but the acctual thing sucked) back on target when she killed my first squad she used 5 twin linked bolters rapid shot... you dont need luck with that fire power and then she got her devestators out

@Ivan: Re: Nova cannon shot. I'm not sure what you think to achieve by dredging up that old post from 2003. The 661 Petaton number produced by NecronLord only highlights the silly disparity between weapon yields - where a ship employs weapon systems that are a MILLION times weaker than the main weapon against the same target. (You might want to put further excerpts from other posts in quotes to differentiate them from your own comments.)

Going by the more recent threads that you posted, I consider that number inadmissible considering that Connor noted that the 22 Petaton number may be too high.

As for the bombardment cannon. The calculation ignores the fact that when firing into the atmosphere, the shell is going to heat up immensely especially at 0.25c. I am too lazy to investigate this at the moment, but it could cause some problems. I hope you realize the calculated yield (even at triple digit TT) is incapable of causing the damage that it is "described" to in the books. At least not without a lot of shots. (likely 10^4 at least)

I really don't know where you are going with all this... None of these numbers mean anything if the disparity between weapon strengths on the same platform are resolved.

-edit- Interestingly, if my hypothesis is correct, and the weapon yields of IoM are limited to the low TT range for novacannon and high GT range for everything else... this changes the dynamic immensely as borderline races such as the Zentraedi become full fledged threats as the values for IoM armor stabilize.

It's 662 teraton,not petaton.

Frazzled wrote:Firing in all directions is irrelevant. Your artillery and less than light speed weaponry is literally standing still compared to an ST ship. It would just look like a porcupine to them.

Let's not go down the path of this idiotic discussion again. That crap went on for like 40 pages last time. ST sucks and is the weakest of all the civilizations in discussion (both in mettle and armament), so let's just stop here.

keezus wrote:

2. Considering that in real-world terms, a 3x difference in magnitude (10^3) is equal to the difference of automatic weapons fire (AK47) vs a 120mm tank round - (Modern armor is pretty much impervious to AK-47 rounds, not so much from modern 120mm rounds) - If capital ships can survive getting hit by low Petaton / High-Mid Teraton level weapons, this would suggest that they would be impervious to torpedoes at the stated yield - even after assuming that the yield of energy weapons is halved by void shielding (since the disparity between the main weapons and torpedoes is over 10^3x and is over 10^5x for the big guns. However, as you've stated that torpedo figures stand - AND we KNOW that torpedoes can damage capital ship armor (and this is backed up by lots of evidence) - there can only be two outcomes here:

Well you do realize that nova-cannons never actually HIT ANYTHING, right? It is a blast weapon, with a radius of a decent sized planet that explodes mid-flight in the midst of an enemy fleet. Being bow mounted, with no other method of steering, it cant be even half accurate, and a direct impact with a nova cannon probably only happens once every five thousand years, and results in instagibbed space-hulks and thoughly baffled tech-adepts. Its like saying troops can survive getting hit by cluster bombs but not AKs.

sniperjolly wrote:

keezus wrote:

2. Considering that in real-world terms, a 3x difference in magnitude (10^3) is equal to the difference of automatic weapons fire (AK47) vs a 120mm tank round - (Modern armor is pretty much impervious to AK-47 rounds, not so much from modern 120mm rounds) - If capital ships can survive getting hit by low Petaton / High-Mid Teraton level weapons, this would suggest that they would be impervious to torpedoes at the stated yield - even after assuming that the yield of energy weapons is halved by void shielding (since the disparity between the main weapons and torpedoes is over 10^3x and is over 10^5x for the big guns. However, as you've stated that torpedo figures stand - AND we KNOW that torpedoes can damage capital ship armor (and this is backed up by lots of evidence) - there can only be two outcomes here:

Well you do realize that nova-cannons never actually HIT ANYTHING, right? It is a blast weapon, with a radius of a decent sized planet that explodes mid-flight in the midst of an enemy fleet. Being bow mounted, with no other method of steering, it cant be even half accurate, and a direct impact with a nova cannon probably only happens once every five thousand years, and results in instagibbed space-hulks and thoughly baffled tech-adepts. Its like saying troops can survive getting hit by cluster bombs but not AKs.

Indeed, if you get hit with a novacannon you are dead.

IIRC: BFG has some special rule if a ship gets directly hit by a Novacannon it dies instantly, but the cannon is highly inaccurate.

I think the Mysterons could obliterate the IoM.

sniperjolly wrote:Well you do realize that nova-cannons never actually HIT ANYTHING, right? It is a blast weapon, with a radius of a decent sized planet that explodes mid-flight in the midst of an enemy fleet. Being bow mounted, with no other method of steering, it cant be even half accurate, and a direct impact with a nova cannon probably only happens once every five thousand years, and results in instagibbed space-hulks and thoughly baffled tech-adepts. Its like saying troops can survive getting hit by cluster bombs but not AKs.

Well you do realize that all the calculations for nova-cannons are BASED OFF KINETIC IMPACT, right?

Aside from the above: Re: Planet sized blast radius: Rounded down for simplicity we'll assume an Earth-like radius of 6000km. Extrapolating from the non-linear blast information based on known blast radii (nuclear in this case): http://en.wikipedia.org/wiki/Nuclear_weapon_yield A 130 TT blast would have a fireball roughly 6000km... (With the shockwave being larger of course). Assuming it is halved by shielding - this would give us a 65TT blast which is magnitude 100x greater than a torpedo. Still a bit on the high side, but not as silly as the 22PT kinetic impact number, or the 660TT number (which is still IMHO too high magnitude 10^3 greater than shield ignoring torpedoes).

Your cluster munition analogy doesn't exactly apply in that both cluster bombs AND AKs are meant to be used on infantry. The 40k problem is that they are using weapons on the same target with power magnitudes so far apart that it is akin to tank weapons and AKs on tanks... the latter of which would be completely ineffective.

I just think that the weapions on the ships of the futrue are always going to be absurd. They have to be to kill stuff. Theres no point argueing exacts like the strength of the warhead if you cant agree on how the thing even works

keezus wrote:
Well you do realize that all the calculations for nova-cannons are BASED OFF KINETIC IMPACT, right?

Yeah, I was just saying that 22 PTs never really happens, but is totally feasable, I mean it is a frigging skyscraper moving at over 3/4 the speed of light.

keezus wrote:
Aside from the above: Re: Planet sized blast radius: Rounded down for simplicity we'll assume an Earth-like radius of 6000km. Extrapolating from the non-linear blast information based on known blast radii (nuclear in this case): http://en.wikipedia.org/wiki/Nuclear_weapon_yield A 130 TT blast would have a fireball roughly 6000km... (With the shockwave being larger of course). Assuming it is halved by shielding - this would give us a 65TT blast which is magnitude 100x greater than a torpedo. Still a bit on the high side, but not as silly as the 22PT kinetic impact number, or the 660TT number (which is still IMHO too high magnitude 10^3 greater than shield ignoring torpedoes).

OK, so my rough guess for diameter was a bit off, it is twice that size, having a radius larger than earth's diameter at about 14K km by using the only canon source, the BFG rulebook. If a ship's base it the few thousand km around it (lets say 3.5K) and the blast template has a radius of twice a ship's base, it would be aprox 14K.

keezus wrote:http://en.wikipedia.org/wiki/Nuclear_weapon_yield

Hmmm... I tought that equation was unworkable due to a devide by zero error. (atmospheric pressure in a vacum is... what exactly?!) Also, no shockwave in space. That said, it is possible that the collision (kinetic impact) is far more powerfull than the detonation, but simply cannot convey that power through a vaccum, thus resorting to an unobtanium, phembletonium, hand wavium, warp implosion warhead. That warhead would probably lessen the mass of the projectile, not really needing an armoured casing. Connor's calcs were based off of being mostly iron.

keezus wrote:
Your cluster munition analogy doesn't exactly apply in that both cluster bombs AND AKs are meant to be used on infantry. The 40k problem is that they are using weapons on the same target with power magnitudes so far apart that it is akin to tank weapons and AKs on tanks... the latter of which would be completely ineffective.

I thought of it rather as firing AT weapons at infantry, while one was never ment to be used against another, was highly impractical and results in an istagib. I used cluster bombs v infantry because I was rushed, nukes v tanks would possibly be a more apt analogy, although a direct hit from a nova cannon was never designed to ever hit anything, EVER.

the nova cannon does make a shock wave.

the gases created by detonation accelerate outwards attempting to fill the void. this transferrs kinetic energy into any solid object it comes in contact with and the knetic energy, while it may be lessoned by the void, will transferr all the energy it can into the only object able to recieve it.

the shock wave doesn't lose kinetic energy as distance increases either(no air resistance) and is only lessoned by, as the distance increases, the fact less and less gas is slamming into ships farther from the blast. Ships will also create zones behind them that won't get hit by the blast(assuming the ship doesn't get thrown into another ship)

Has anybody mentioned the Yuuzhan Vong from star wars, they are a speices that took over pretty much most of aother galaxy before falling to infighting and pretty much destroying the entire galaxy before fleaing to the star wars galaxy, they hate machines and use bioweapons. They are immune to most force abilites so it would lead one to belive that they would have a similiar affect on psychic powers apart from lighting attacks since they can be hurt by force lighting attacks.

There ships don't have normal shields, instead they use artifically created black holes to absorb incoming weapons fire, but these can be overloaded by fireing low power shots constantly at the generators, but on larger ships this flaw is stoped by having many generators, allowing others to "recharge" while others prevent incoming fire.

I think they could take on the IoM in a fight since they wipied out over 365 trillion people in their short 4 year war with the New republic/Galactic Federation of Free Alliances and the empire, but I'm not sure who would win.

Grey Templar wrote:
IIRC: BFG has some special rule if a ship gets directly hit by a Novacannon it dies instantly, but the cannon is highly inaccurate.

It's not in any set of rules that I have. The effects will just about instantly cripple a ship, but it won't automatically destroy it.

Cheers

Andrew




Automatically Appended Next Post:

IvanTih wrote:About 40k STL speed.
In flight of the Eisenstein they were accelerating to reach Holy Terra to inform the Emperor of Horus' treachery. Also when the Eisenstein is found by the Imperial Fists they came out of the Warp 4 light minutes from the Eisenstein, which Garro noted was little time to prepare for their arrival. Later a Black ship matches speed with them after they clear Neptune, while at .75c. All of which implies fairly high acceleration.
Then again we have 0.75 from Sabbath Matyr.
Remember that Rogue Trader contradicts itself(we have freighter travelling at 3000 km/s while we also have single digit G,blame Andy Chambers who also gives them single digit in Rogue Trader novels).

However, speed =/= acceleration.

Since there is no friction in space, there is nothing to slow you down. Therfore, theoretically a ship with only 1G acceleration (10meters per second) can reach 3000 kms. It just takes 3 and a half days of constant acceleration.

Cheers

Andrew

sniperjolly wrote:I used cluster bombs v infantry because I was rushed, nukes v tanks would possibly be a more apt analogy, although a direct hit from a nova cannon was never designed to ever hit anything, EVER.

Order of magnitudes buddy... orders of magnitudes... The problem with BFG is that it is stuck in a purely WWII naval warfare mindset. In WW2, in ship to ship combat, the participants usually fired everything they had at the other ships - main batteries, secondary batteries, torpedos - I wouldn't be surprised if they even used the AA guns, if they were in range. The secondary guns (and smaller weapons) had zero chance of penetrating the actual armored belts but could destroy exposed superstructure, men and materials on deck. A notable example is the WWII battleship Bismark. The British shelled her relentlessly from sea and air and managed to penetrate her armored belt exactly 0 times even with direct hits from torpedoes and main batteries. Her rudder, superstructure and surface elements were obliterated but she was still afloat. In 40k, where all the vulnerable guts are enclosed by the armored hull, firing secondary and tertiary armaments at a target that can resist your primary batteries is nonsensical as no amount of cumulative hits from the secondary on down will cause any damage... So here's the issue... We'll use torpedoes as the measuring stick, as they're STATED to be 610GT - each wave of torpedoes (repped by a counter) does 1 pip of damage, so they're supposed to be moderately effective.

Torpedo - 610GT
Ordinance / Lance battery - supposed TT range (10-1000x greater power)
Novacannon blast - per above posts: TT range (100-1000x greater power)
Novancannon direct - PT range (10000-1000000x greater power) - inaccurate.

In my mind, orders of magnitude should not exceed 100x for the entire range of anti-ship guns - something along the lines of:

Torpedo - 610GT
Ordinance / Lance battery - single digit TT
Novacannon blast - double digit TT
Novacannon direct = instagib


Automatically Appended Next Post:
Damn. When did I become a Mysterious Techpriest?!??

although, Physical impact is magnified in space as the kinetic force has nowhere to go, but inside the ship. the same can be said of most heat(only Radiative heat can enter a Vacum)


Penetration isn't required to do damage. Vibrations can damage and destroy equipment and only a small crack in the armor is required for a deadly decompression of the interior.


That said, very few IoM ships are lost(aside from puny escorts) by being totally obliterated by fire. mostly its the loss of onboard pressure and impacts breaking vital equipment causing the ship to become dead in the void. Impierial Captains frequently detonate their ships reactors to prevent the ships wreck from being looted too.

keezus wrote:
In my mind, orders of magnitude should not exceed 100x for the entire range of anti-ship guns - something along the lines of:

Torpedo - 610GT
Ordinance / Lance battery - single digit TT
Novacannon blast - double digit TT
Novacannon direct = instagib

I think that that is even overstating the abilities. A single torpedo does 1 point of damage, 610 GT. A Lance does 1 pt damage, if 610 GT can do that why should the lance be of magnitudes greater?

Andrew

the lance does put more energy out, but that energy is used to bypass void shields rather then damage the ship.

it's also like the difference between a Club and a knife. the clug does equal total damage over a greater area while the knife does equal total damage over a smaller area.