Rogue Trader (FFG) ship details

[RCgothic]

Which makes zero sense as you're in outer space.  Even if you ARE using brute force, it would only take one guy to move a macro cannon shell the size of a freight train into position.

Not if you want that shell loaded quickly. It would still take all that person's might to make the shell move, and all his might to stop it. If it gets even a little bit of speed going, it would crush him as though he weren't there. Inertia is a bitch. He's not going to be able to move it fast, and he's not going to be able to move it accurately. It could easily take 100 people to manhandle that single shell, even in zero G, and there would be other shells behind it in the queue.

[Admiral_d_Artagnan]

...it only has two weapon hard points on it's dorsal mount.  The sunsear is a range 9 str 4 weapon.  The standard Macrocannon (when not mounted as a broadside for a cruiser) is a range 6 str 3 weapon.  In BFG, the Sword has a str 4 weapon, meaning it theoretically get twice as much firepower in RT then it does in BFG.  (since weapon str seems to convert directly, *most* of the time.)  

Weapon stats in BFG are not exact. When one says WB Firepower, the value is just representative of how strong it is. It is very much different from 40k weaponry. You can't even directly convert the ranges much less the strength between both game systems. RT which might come close still has a different game mechanic and so still can't be directly converted.

[Dragon Lord]

So, even figuring that the Lunar has three watches, (which is NOT what they do, supposedly) why would you need 30,000 men on duty at any given time?  The batteries are stated in Blue book to only require 40 men per macro cannon.  What do they do, form a human chain that carries the individual loads from the magazine by hand?

That sidebar that mentions 40 men operating a macro cannon also describes the shells for the cannon concerned as weighing 'several tonnes'.  In comparison to the size of a BFG ship this is not all that large, the shells fired by the main guns of an Iowa class battleship were 0.9-1.2 tonnes.  Even the largest gun ever built is small in comparison with a BFG ship and that used 5-10 tonne shells.  A couple tonne shell would be something like 0.5m in diameter, but if an Imperial cruiser is 5km long then from the models the main guns in a broadside weapons battery must have barrels with a calibre of the order of 50m, for which you must be talking about shells weighing thousands of tonnes.  Not that I am a fan of the 'doing everything by hand and brute force' imagery for Imperial ships but if you scale the number of men required for each of those main guns by the tonnage of the shell from that 40 man gun you would be talking about up to 10,000 men just to operate one gun, and a Lunar class has eight guns that size...
As I said though I prefer to think that there is a little more automation going on, so that giant gun would not be being moved into place or loaded by hand, but even so there must be a lot of people around to monitor the machinery and step in if something goes wrong, which in a battle situation something will as a result of battle damage.  On a ship 5km long the damage control teams alone must be enormous; while I don't necessarily agree with RCgothic on the rat problem he is right about the millions of kilometres of wiring there must be in a ship this size, when things start shorting out during battle you don't want the nearest repair team to be 130 decks below and a kilometre aft of where the damage is.  Also with regard to laser weapons not having ammunition to load, this depends in part on what sort of laser you are talking about, chemical lasers, which are the type currently under investigation for military use actually do have ammunition in the form of the reactants, though they would probably be fed directly into the weapon from reserves rather than requiring 'loading'.  Aside from that high powered lasers often have various components that need regular replacement because of the enormous power loads going through them, indeed the background for the Armaggeddon class battlecruiser describes the problem of the extra crew required to deal with the replacement of the power relays to the dorsal lance array that burn out on a regular basis, and you would want people monitoring the power supplies to the lasers so they can take action if something overloads.
So for me at least, even if you disregard the retrotech elements (which I am more inclined to do to some extent at least) I can easily see an Imperial cruiser needing a crew of over 100,000.

Dragon Lord

[BaronIveagh]

Given how old these ships are, how many millions of kilometers of wiring there would be even in a Sword, and how infested with Vermin (that really do like to chew on cables for no reason except extreme risk of death - rats are seriously weird) they are, it probably takes a good few thousand working ceaselessly just to keep the thing operational. It's a full time job for 200 people just to keep the Forth Bridge painted, and the surface area on the humid interior of even a sword is going to be much vaster than that, let alone the exterior and fixing minor battle damage (such as a 50m wide crater blown in the superstructure - not worth going back to port over) is going to be an enormous workforce.

Then there's the standard 40k Trope of Insanely High Tech right next to the pre-industrial. It may be that the ship has Thrusters that can bring its entire bulk onto a new course in a matter of minutes, but to move just one into facing the right direction for a manoeuvre takes 500 strong men ten minutes on a treadmill.

It may be that the plasma reactors at the heart of a starship can put out enough power to light modern day earth, but just keeping it supplied with fuel requires 1000 men full time on hand pumps.

Now I'm not saying they were originally designed that way, but as the ships ages, certain pieces of technology fail that no-one knows how to replace and work arounds have to be employed. The manual labour EASILY mounts up.

... I'm trying to picture how hand pumps would ever work on a tokamak and not getting any hits...

Second: why would the interior areas of anything but certain sectors be humid?  Excess water in the air would be extracted at life support for additional drinking water.  

Granted, DCT and maintenance would be a few thousand men easily.  The problem is that, unlike modern day earth, outer space tends to preserve equipment rather then destroy it.  

It seems like the assumption people are making is the majority of the ship is hollow, as it would be in a modern ocean going ship.  In space, the majority of it would probably be metal, the mass of it serving to shield the crew from solar radiation.  This would, of course, be riddled with maintenance accesses, plasma conduits, gun ports, docking bays, electrical conduits, etc.  

At one point I seem to recall having done the math that a Lunar, if it followed the same ratio as a modern ship, would only have something like 1/100th of it's interior pressurized.  


Edit:  Found it.


"A lunar class is approx 5,000,000,000m^3 (approximation based off of GW mini)

Approx 1/100 of that space will be pressurized areas accessible to the crew, or 50,000,000 m^3 (the rest being armor, engines, mechanical systems, exterior defense turrets, etc.) (used modern space craft for this estimate)

Three quarters of that would be given over to areas for engine access/fuel storage and weapon related areas (magazines, interior areas of macrocannon batteries, engine access corridors, etc)  (used a battleship and GW mini for estimate), leaving 12,500,000m^3

Now, hanger bays, work shops and fabrication areas, medical facilities, kitchens, officers quarters, armories, escape pods, command and control, spare part stowage, cargo areas, and ships gravity plating.  3,000,000m^3 remaining. (used battleship for estimate)

Now we add berths for the men.  Hmm... if we assume voidsman's quarters are the average for the remaining crew, and a voidsman gets a 6'x8'x10' berth (rather then a navy bunk) that's 3,000,000m^3 there for 20k men.  We're out of space before we even got to life support and food storage.If we halve it (10k) everything fits, and there is even a little space left over.  Which fits the Chambers model."



Admittedly, it's flawed, as it's based on the mini, and we all know how GW loves artistic license even on basic things like human bodies...

Weapon stats in BFG are not exact. When one says WB Firepower, the value is just representative of how strong it is. It is very much different from 40k weaponry. You can't even directly convert the ranges much less the strength between both game systems. RT which might come close still has a different game mechanic and so still can't be directly converted.

Achem: D'Art, in Rogue Trader, if you put a Macrocannon broadside (str 6) and a Titanforge Lance Broadside (str 2) on a Lunar class hull... it has Str 6 WB and Str 2 lance.  Does this sound familer? 

The weapons ranges don't convert directly, but the weapons str are a direct conversion.  I won the contest over at FFG for doing conversions between the systems (admittedly, it was for the mimic engine, but...) I think I know how to convert between the two at this point...

[Dragon Lord]

The problem is that, unlike modern day earth, outer space tends to preserve equipment rather then destroy it.

While it is true that they wouldn't need to worry about rust and corrosion (on the exterior at least, the interior of pressurised compartments can still rust) weapons fire would be just as destructive and equipment would wear out just the same, more so in some cases as things would get hotter in vacuum conditions where there is no air to cool them.

The problem with estimating things from small fractions of an initially large number is that in terms of the original large number small errors in your estimate lead to large errors in the result.  What if rather than 99% of the ship being unpressurised or otherwise inaccessible it is 98% or 97%, not much difference if you are concerned about how much is inaccessible, but it would double or triple your crew estimate.  Indeed if it is actually 2% of the ship that is pressurised and accessible, only 70% of the accessible space is engine access/weapons magazines etc. rather than 75% and the crew quarters are bunks rather than single rooms the crew estimate goes up to FFGs 96k.  Admittedly the method of upscaling things like battleships and aircraft carriers has problems too, but the inhabitable volume method just tells you how much space there is for crew to go in, not how many crew the ship needs.  In terms of upscaling things perhaps the best estimator of what you would really have on a space craft would be a submarine, since they have the same sort of concerns about oxygen and atmosphere recycling that a space craft would have.  Unfortunately submarines are also rather smaller in general and even using the Typhoon, the biggest class of submarine ever built and I believe supposedly relatively spacious, with your 5,000,000,000m^3 estimate for the volume of a Lunar gives a crew estimate of the order of 10 million, which even I think is too big!

Dragon Lord

[Plaxor]

Yes. Heat is an issue with spaceships. They actually talk about this a lot in Mass Effect.

Space is cold, and due to movies and tv people think that space is so cold that it will freeze you instantly.

It would actually take several days... weeks... years (I don't really know) to reach freezing from room temperature.

In order for something to get cooler it needs to transfer its heat into something else. Less dense materials take in heat less efficiently. This is comparable to how 10'centegrade (50 Fahrenheit) water feels a hell of a lot colder than 10' air.

Space has a density ridiculously low, something like a dozen hydrogen atoms per cubic meter. So it would take forever to cool down.

This is presented in the mass effect 'fluff' in that starship reactors, and weapons produce a lot of heat, so much that they can't sink it in any reasonable timeframe. If ships don't discharge their heat then they will literally cook their crew alive. So iirc ships have to discharge their heat in a planetary atmosphere, which is usually a gas giant.

I think they go into certain types of systems which allow ships to fight for longer periods. One of these technologies is a pottassium evaporator, that essentially makes the ship 'sweat', and as the pottassium evaporates in the vacuum of space it is cooled.

This is how swamp coolers and sweat works, but they would be more effective in a vacuum, as most liquids (if not all) can't exist in those conditions. Most solids sublimate, much like dry ice.

Of course the pottassium would have to be replaced after each battle, but if it can double the amount of time that you can fight.... well then it's probably worth it.

[Admiral_d_Artagnan]

Achem: D'Art, in Rogue Trader, if you put a Macrocannon broadside (str 6) and a Titanforge Lance Broadside (str 2) on a Lunar class hull... it has Str 6 WB and Str 2 lance.  Does this sound familer? 

The weapons ranges don't convert directly, but the weapons str are a direct conversion.  I won the contest over at FFG for doing conversions between the systems (admittedly, it was for the mimic engine, but...) I think I know how to convert between the two at this point...

No it is not. Sorry but the weapons stats on a ship which is kilometers long is different from an individual weapons. It is not a direct conversion on scale alone. Anything can sound familiar. 40k weaponry has Str 4-7 on a whole slew of them. RT's description is specific to Macrocannons and Titanforge Lances. These two are still different and the former and most likely the latter would only be a part of the Weapon Battery section since there is a problem with the ranges.

Again, WB and lances in BFG are very much different from that of RT which is another game.

[BaronIveagh]

Achem: D'Art, in Rogue Trader, if you put a Macrocannon broadside (str 6) and a Titanforge Lance Broadside (str 2) on a Lunar class hull... it has Str 6 WB and Str 2 lance.  Does this sound familer? 

The weapons ranges don't convert directly, but the weapons str are a direct conversion.  I won the contest over at FFG for doing conversions between the systems (admittedly, it was for the mimic engine, but...) I think I know how to convert between the two at this point...

No it is not. Sorry but the weapons stats on a ship which is kilometers long is different from an individual weapons. It is not a direct conversion on scale alone. Anything can sound familiar. 40k weaponry has Str 4-7 on a whole slew of them. RT's description is specific to Macrocannons and Titanforge Lances. These two are still different and the former and most likely the latter would only be a part of the Weapon Battery section since there is a problem with the ranges.

Again, WB and lances in BFG are very much different from that of RT which is another game.

Let's try this theory out:

Lunar hull has two broadside weapon slots and a prow weapon slot.

Dominator is a str 12 WB.

Putting two Macrocannon broadsides in a lunar: Str 12  Huh

Gothic is a str 4 lance

Put two titanforge lance batteries in those slots, it's str 4.  huh.



Let's try a non-IN hull!

Murder is WB str 10, and is specifically plasma batteries

Putting two Mars pattern plasma batteries in it's two broadside slots, wow, str 10.  I wonder how that worked?

[Admiral_d_Artagnan]

Ooh! Ooh! Let me try:

Inferno Cannon: Str 6 put 2 of them together and I get Str 12 in a Dominator hull! See I can play this game too, Wheeeee!

Point being: Different gaming system.

[Valhallan]

no matter how hard anyone tries there is only one true fact:

the warhammer (and 40k) universes' fluff *is not* logical. in any way shape or form whatsoever.

[BaronIveagh]

Ooh! Ooh! Let me try:

Inferno Cannon: Str 6 put 2 of them together and I get Str 12 in a Dominator hull! See I can play this game too, Wheeeee!

Point being: Different gaming system.

Except that the inferno cannon isn't a starship weapon system.  All the one's I used were.  

Getting back to your original assertion that Swords used macrocannons, it doesn't.  Blue Book's fluff for the sword says lasers.  FFG's fluff for the lasers says lasers.  FFG's fluff for the sword says lasers.

Therefore, the Sword, at least, is armed with lasers.  

For converting ranges, below 4 is 15cm band 5,6,7 is the 30cm band, 8,9,10 is 45cm band.  10+ is 60cm band.  It's not absolute though.  And sometimes a weapon will trade a point of str for a +10 to ballistics tests from BFG to Rogue Trader, such as the starcannon.  the +15 pt range boost seems to be roughly analogue to the turbo weapons upgrade taken at 'best' level combined with the auto-stabilized logis targeter.

(for extra fun, you still have to use macrocannons/wb and then lances for effective damage)

As I said, the only real oddity is that frigates seem to fire in the 45cm band instead of the 30cm band.  

[Admiral_d_Artagnan]

You're still just assuming with the ranges. Sorry, won't easily fly since you can't even nail it down.

[BaronIveagh]

You're still just assuming with the ranges. Sorry, won't easily fly since you can't even nail it down.

What do you mean 'can't nail it down'?  

The reason it's 'not absolute' is the character controlling ships gunnery can impact effective range AND the GM can arbitrarily change the value of a VU (see frozen reaches).

As far as ranges goes:

A Fury moves in BFG 60cm in a line over the course of two turns ord phases.  In Rogue Trader, a Fury moves 10 VUs in the same relative time. (this is due to Ordinance and Eldar having their base speeds doubled since there is no Ordinance Phase for them to move in)

The Murder in BFG's prow lance is a 60cm weapon.
The Murder in Rogue Trader's prow lance is an 11 VU weapon.  

So, why does a ship weapon who's real range is 20-25 have  range in BFG of 30cm?  Answer: because all ranges in BFG are rounded up to the next number divisible by 15cm.  

Until the next expansion, no weapon with a range greater then 60cm has been released, so we'll see if the formula continues.

Ship speeds:

Direct conversion of ship speeds are a bit odd.

Where RT and BFG part is the fact that individual ships can have very different profiles within the same class, as Rogue Traders, unlike IN, can heavily customize their ships (way above and beyond what they can in BFG).  This leads to some oddities like (equiv) +6 armor all around Lunars and 60cm move equiv Havocs.

Further, smaller combat ships have gotten speed boosts (between 5 and 10cm equiv) over all due to this being a ship on ship game rather then a fleet game.  This was done for balance reasons.  

Basis:

Lunar: BFG: 20cm
         RT: 5VU
Transport: BFG: 15cm
               RT: 4VU
Arconite:BFG: 60cm per turn top band
            RT: 14 (approx 65cm)
Sword: BFG: 25cm
          RT: 8 (approx 40 cm)

Known Exceptions:
Dauntless: BFG: 25cm
               RT: 7 (equiv 30 cm)
Why?: AAF (Flank Speed) and Improved Thrusters do not work quite the same way in RT.


So, actual distance for ships from RT to BFG terms

VUs:  4    5   6    7   8    9   10   11  12  13  and so on
CM:  15  20  25  30  35  40   45  50   55  60   and so on
            

[Admiral_d_Artagnan]

As you pointed out, this is a ship on ship game. Not a fleet on fleet game. There's still differences involved especially with the ranges where you have an effective range and a VU that can change.

[Eldanesh]

There is one Problem: neither scale nor timeframe in ANY Games workshop game is linear. Miniatures, Markers and Terrain don't even share the same scale.
E.G. some Areas have a Planet and a Moon of this Planet on the Table - something that is close to impossible as long as you asume a scale of 1cm=1000km and don't play on a gaming table of 4 metres or more! (the minimal distance beteween earth and moon is 363.000km!).  
In other games it is the same: in 40k 12" weapon range isn't even the same than, say 12" movement. Horizontal distance is not the same as vertical distance. A Space Marine miniature is ~3,5cm high, representing a ~2,5m high Space Marine. So 1cm is ~0,7m. A Bolter has a maximum range of 24"(61cm). Does anybody believe that it can fire only over 43 metres?  
A "gameturn" doesn't represent the same timeframe: while over long range Artillery-battles it represents a longer time up to an hour or so in close combat it only means some seconds/minutes. And so on...
There even was some statement in an old WD about this.

There is no real "scale" in this games and this is why you can't take data from them except the most basic like "a sword has higher maximum speed than a Lunar".