Ship size... smallest viable warp capable ship

By ZeroState, in Dark Heresy

Hi all,

As far as I can tell, the smallest naval warp ship in the Imperium is going to be a destroyer. Would the Navy have smaller couriers or other craft? Also, what is the smallest viable size for a warp capable ship - fluff references preferred of course?

I'm not aware of any real data in this regard. Some 40K novels mention small ships. Others, nothing smaller than a kilometer. If you're looking for a definitive answer, I don't there is one.

I realise this might be the case, but in lieu of actual fluff, I invite speculation.

I can't remember the source but IIRC smallest Warp-capable ship are ~500m long.

There are a couple of smaller ships in various novels. These ships are small by 40k standards, but are still sky scrapper sized.

There are several occurances in the fluff of small warp capable ships - however it is likely that the smallest standard warship in the Imperium is the Cobra Destroyer (and similar vessels) but that there are are a considerable number of smaller ships employed by different organisations like the Inquisiton, Navigator Houses, Adeptus Mechanicus etc who have access to more advanced drives - be they just better (often older or experimintal) or Xenos.

Check out the Rogue Trader thread on this same point. There is apparently an approx 200 foot long warp capable vessel with a single navigator and astropath mentioned in one of the Black Library novels.

Size*Technology = constant. If you go deep enough into the DAoT, you might find fighter-sized warp capable ships. For "modern day" tech, the Cobra is likely the smallest ship available to the navy.

I'm not sure I agree, Cifer. Putting aside the 200 foot warp capable vessel, every navy has a selection of vessels smaller than a destroyer that nevertheless make long voyages. Cutters, Corvettes etc etc. The Cobra Destroyer is the smallest vessel worth replicating in the Battlefleet Gothic game, but it doesn't necessarily mean it's the smallest warp capable vessel in existence , or even in use in the Imperial Navy.

I'm not aware of any canon (grrr-hate that word) sources for smaller warp capable naval vessels, but I'm notaware of any "scientific" principle ever being set out which would preclude smaller ships...

And logically, if there's a weird Imperial "special" ship which is only warp capable and only 200 feet long, why would there NOT be an intermediate vessel class between a cobra destroyer and that ship?

I've never seen an indication of a minimum/maximum mass for any warp vessel in 40K. As far as I know, as long as it's air tight, has a warp drive and a gellar field, it can enter and exit the warp. Of corse, drives and field generators may be the kings of things that are only feasibly constructed on a massive scale.

I don't recall ever seeing the 200-ft reference- I remember seeing a reference in Eye of Terror to a small freighter that was 35m tall (belly to back), and a reference in Inquisition Wars to the Tormentum Malum being small/advanced enough to require only 3 crew. Angels of Darkness outright states of a 750m long ship was 'only just larger than the smallest possible size', which I interpret to mean that is is unfeasible to cram sufficient life support, power plants, fuel, geller field generators, warp engines, conventional plasma drives and all the other necessary pre-requisites into a hull smaller than ~700m. It may be physically possible to do so, but only at the expense not being able to physically fit the crew aboard.

Alternatively, it may be possible to do so, but the utility of doing so is far outweighed by the expense of doing so- which could well be a corollary to the difficulty of securing the technology to build and/or maintain the thing.

I'll also note that I suspect that the Navy has a number of smaller vessels, possibly even down towards the 200-ft range (although that sounds like an outsized small craft rather than a stand-alone vessel to me- hell a ship-killer torpedo is 200ft), but I doubt that they are considered combatants- and if they are they are probably SDBs used to guard the approaches to Naval bases. I suspect that the 'destroyer' band of classes represents the smallest feasible size for a warp-cabable warship, but the navy may well maintain smaller ships as dispatch vessels (for correspondence that cannot be transmitted via astropath), training ships, yachts for flag officers as well as the aforementioned guard ships

I don't recall it mentioning its size but the first Grey Knights novel (by Ben Counter) is the one with the tiny and fast messenger ship, with just pilot and Navigator - kind of got the impression that it was a rare, rare (defo Ordo Malleus) ship though....

Obviously you could reduce a ship right down (square-cube law being what it is) but 'they' wouldn't. Probably the DAoT corvettes and the like got worn away by attrition, leaving the destroyers as the smallest type readily available (since they're more survivable) - like the bit on page 157 of IH mentioning a destroyer leading fleets on a campaign against pirates: you'd think a corvette would be enough, if they had them.

Likewise Chaos raiders being DD-sized: total overkill to hit merchant shipping....

Thanks for the info. I think I'll go with 300m long (and take other proportions from the smaller BFG minis) as the smallest Imperal ship you're likely to come across - a courier perhaps. I'll also file away that two crew courier - in the source mentioned, did it have many/any (I'm sure there must be some) servitors?

Actually I am just reading the Grey Knight Omnibus. The Courier ship had a Pilot/Courier and a Navigator. The pilot basically flew blind through the warp while the navigator gave him verbal instructions. The ship itself was not described in any detail other than it was small, very, very fast, and very, very, very, very rare and the Inquisition hated to use it but had no choice in the situation.

The impression I got was it was little more than a Plasma drive, Warp Drive, Gellar Field Generator, two seats, a stick and a blind fold for the pilot all wrapped inside a cone.

How about this for an alternate no-canon idea.

Smaller ships are possible, but are incapable of preforming sustained warp travel. It has a warp drive but no "engine" to power it, it has to be "charged up" from the plasma drives pre jump, because during the jump the plasma engines power the gellar field. it is capable of small warp "hops" but nothing more than that and maybe 2-3 max before some kind of maintenace is needed. Complete crew compliment of no more than 10, with space for 10 or so passengers, due to the small distances involved, "hydroponics" and other facilities are not on board either, the gally is nothing more than a current modern day kitchen with a dinning table, force everyone one board to bring their own food stuffs and the crew to eat in shifts.

Nah, you jump into the warp and jump out of it at the end of the journey IIRC. If you can't move in the warp, you are at the power of the warp...

However - I'm not sure I understand you correctly - please expand...

Actually, the Star Wars RPG (old West End Games) version covers this concept pretty well - in that game many starfighters had hyperdrives that could launch them across interstellar space, but often these would be limited to a set number of jumps. For a larger number of jumps starfighters required Astromech Droids like R2D2.

In 40k, I speculate that the tiny courier vessels mentioned in the Ben Counter book are not really VIABLE as anything other than a stopgap emergency measure because their tiny engines can only make a limited number of jumps.

Plus, in 40k there is a lot of talk about the "Tall ship" approach, ie an approach designed to create the impression that space voyages are lengthy (months or years long), dangerous and an adventure in themselves. Dark Heresy is NOT Star Wars, the warp is not hyperspace, and it doesn't take a few seconds of blurred stars to travel across the galaxy: it takes years of travel through a daemon infested parrallel dimension.

So using a 2 man courier ship to cross any great distance would be like crossing the Atlantic in a rowboat - theoretically possible (just) but incredibly dangerous, unlikely to work well consistently and something of a waste of resources.

If warp engines can be shrunk down to fit in a 200 foot vessel, (which apparently they can, even for short voyages or a limited number of jumps) one would have thought that the real limitation on space travel is how much food can be carried. If you can imagine that this 200 foot vessel is so small that it can only just seat two men in a space similiar to that of a 2-seater car, there is not likely to be much space for food. Dark Heresy repeatedly states that travel across even the Calixis Sector (a relatively small space in cosmic terms) takes MONTHS.

If you also factor in the large crews of 40k vessels (due to a lack of computerisation and mechanisation) and the great expense of constructing vessels, economies of scale dictate that it would make sense to build BIIIIG ships all the time. If some planets only get visited by trader every ten years or so, you'd rather be visted by a ship capable of carrying a million tonnnes of foodstuffs and goods than a two man ship with a glove compartment full of pringles. happy.gif

Small ships don't really confer that many advantages, really: they're not likely to really be any faster than large ships, can't carry as much weaponry or cargo...the only real advantage I can think of is that they are probably harder to detect.

So I reckon the Imperium CAN build ships smaller than 750 metres, but I reckon they would only RARELY build such ships. There may be a few 300 metre cutters or corvetes used by the Navy, but as the only real advantage seems to be stealth, I'd imagine that REALLY small ships are probably limited to being used by certain sinister Imperial agencies like the Officio Assasinorum, Ordo Malleus etc...

If we're talking real science and engineering, it is far more efficient to have smaller ships (higher payload to volume ratios, per structural strength necessary to withstand a given acceleration); the square-cube law I mentioned before (volume increases mass and therefore inertia, at the cube, but strength only at the square, so you need to give more volume over to reinforcing the structure ... which, in turn increases the mass and so on).

But yeah, start handwaving inertial compensation fields and antigrav and all bets are off! gran_risa.gif

I think it's pretty clear that every team of Acolytes should have its own Ebon Hawk! gui%C3%B1o.gif

Per your analogy, for that messanger ship in the novel, I kind of got the impression that in an age where technology stopped at a certain point, leaving mostly tall ships to posterity, the CIA/NSA etc of the time had managed to keep a fusion-powered speedboat, sent across the stormy Atlantic at the hands of its best pilot and navigator....

In the novel "Eye or Terror" by Barrington J. Bayley a "rogue trader" has a warp capable ship that can be piloted by just one person. Though it still require that the pilot has the navigators gene (warp sight) to navigate the warp. There is no exact size description of the ship, but its clear that the area they can occupy in the space ship is very small.

The novel is really great, and it gives a great introduction to how warp travel works and what the ruinous powers are in 40k. I can warmly recommend the book.

In my game the Logicians have small (50-100 meter) ships capable of warp travel...

My acolytes are stuck with the larger vessels

The chartered captains mentioned in the Dark Heresy rulebook actually make short jumps into the warp without Navigators... sounds dangerous to me. Also, the Tau use a similar system, though presumably with better computers.

I wonder if this has any bearing on the size of a vessel?

As, apparently, the smallest vesels need Navigators to traverse the warp in any meaningful way, what do the Chartist Captains use? Huge supercomputers to do the navigational calculations? Banks of servitors with their minds linked together to form one gestalt servitor supercomputer? Maybe this is why some of the Chartist ships - like the Miserichord - are so enormous? (The MIserichord is stated in IH to be about the same size as an Emperor class Battleship.)

Perhaps the use of a Navigator allows ships to be smaller, as the warp engines can be directed more precisely and less power is therefore needed?...Plus you don't need huge crews to maintain the huge power generators and warp drives...or vast crews of techmagi to look after the navicomputer...

All speculation of course! happy.gif

Eye of Terror is an abominably written book. Admittedly, that doesn't mean I don't like it, but it is incredibly poorly written, well below Mr. Bayley's usual standards. It doesn't give much of a description of Rogue Trader Rugolo's ship, but it does give us a belly-to-back measurement of 35m, as I mentioned earlier. Extrapolating from the common dimensions of ships in BattleFleet Gothic (and acknowledging that such an extrapolation is risky, given that we know the BFG models do not even have a coherent and common scale within one model), we can assume maybe 250m-300m length. Given how much the rest of the novel differs from the commonly accepted canon, I don't know whether we can accept that as accurate. However, much of that canon comes from later sources, so...

I'll also note that the proportions are not absolute. While much of sci-fi assumes that a ship will be longer than it is tall, or not as wide as it is long, anyone who has watched Firefly, or played Homeworld can tell you that doesn't have to be the case.

On the subject of cube-square laws: you're right, but there is a minimum size before that comes into play- economies of scale, and so on, meaning it may not make sense to build something smaller than a certain size. There is also another datum to consider- sophistication. At a given level of sophistication (of technology, technique etc) a smaller unit will be less capable (and cheaper, in both an energy/labour sense and a fiscal one) than a larger one. To maintain roughly equal degrees of capability in a smaller package would require a more sophisticated (and hence more expensive) approach and technology. The question is therefore, whether the cube-square laws are sufficient to justify not building large to get the extra capabilities (and in fairness, they do, beyond a certain point- a GC, or BB is pushing that limit according to BFG, so presumably a DN or SD has past the point of diminishing returns in terms of maneuvrability, in much the same way as ork roks, hulks and kroot warspheres have. I guess it's a case of 'where do the graphs cross?'

Let's face it, we're all sci-fi fans here. We are all a little bit obsessive about the details. I LIKE reading about the precise details of a ship's size, complement etc...it brings the fiction alive for me.

I've been told a number of times on the BL forums that we shouldn't WANT to discover these details, that they're not strictly speaking necessary for the enjoyment of either BFG, BL fiction or Dark Heresy...well of course, this may be true, but why NOT just go ahead and pander to our obsessive compulsive sides? Why NOT produce a beatifully drawn book which contains full technical details of a BFG cruiser? I'd buy it...and pay a lot of money, too!

The new Rogue Trader book sems to me to be the ideal place to address these points...I hope FFG seize the nettle and clear up a few of the ambiguities about interstellar space travel and Imperial ship scale.

I'd love to see a huge pull out size comparison chart in the new Rogue Trader, like they used to do in Call of Cthulu, with various ship classes and space stations on it...

from france

if i remenber correctly the novel "grey knight" a small one man( in this case a woman) ship crew capable of warp travel. the only obligation is that it must be a psycher because it needs to follow the light of the astronomican.

If we're talking real science and engineering, it is far more efficient to have smaller ships (higher payload to volume ratios, per structural strength necessary to withstand a given acceleration); the square-cube law I mentioned before (volume increases mass and therefore inertia, at the cube, but strength only at the square, so you need to give more volume over to reinforcing the structure ... which, in turn increases the mass and so on).

As has been said by Alasseo, the demands of that law intersect with those of miniaturization - if the real costs of building the vessel are in the Gellar Field and the Plasma and Warp Engines (and miniaturization of those may be technologically impossible or rather expensive), making the few thousand tons of structural reinforcement and hulll plating basically just a fiscal afterthought, we might get a situation where building few big ships is more efficient than a fleet of small ones.

As, apparently, the smallest vesels need Navigators to traverse the warp in any meaningful way, what do the Chartist Captains use? Huge supercomputers to do the navigational calculations? Banks of servitors with their minds linked together to form one gestalt servitor supercomputer? Maybe this is why some of the Chartist ships - like the Miserichord - are so enormous? (The MIserichord is stated in IH to be about the same size as an Emperor class Battleship.)

Perhaps the use of a Navigator allows ships to be smaller, as the warp engines can be directed more precisely and less power is therefore needed?...Plus you don't need huge crews to maintain the huge power generators and warp drives...or vast crews of techmagi to look after the navicomputer...

Chartist captains just use charts of the stars and the warp currents, essentially pointing their ship into a certain direction, entering the warp, driving a while, exiting the warp and seeing where they got before correcting the course and repeating the procedure until they got to their target.
Computers are certainly involved, but they're not capable of supplanting a navigator - that would require a thinking machine and therefore be tech-heresy. I don't think vessels would become smaller through the addition of a navigator.

I'm not sure I agree, Cifer. Putting aside the 200 foot warp capable vessel, every navy has a selection of vessels smaller than a destroyer that nevertheless make long voyages. Cutters, Corvettes etc etc. The Cobra Destroyer is the smallest vessel worth replicating in the Battlefleet Gothic game, but it doesn't necessarily mean it's the smallest warp capable vessel in existence, or even in use in the Imperial Navy.

I'm not aware of any canon (grrr-hate that word) sources for smaller warp capable naval vessels, but I'm notaware of any "scientific" principle ever being set out which would preclude smaller ships...

And logically, if there's a weird Imperial "special" ship which is only warp capable and only 200 feet long, why would there NOT be an intermediate vessel class between a cobra destroyer and that ship?

For the same reason not every imperial soldier wears power armour - the 200 feet ship is an anomaly, a miracle of technology no longer understood. Those ships smaller than a destroyer usually seem to hitch rides with the larger crafts.

if i remenber correctly the novel "grey knight" a small one man( in this case a woman) ship crew capable of warp travel. the only obligation is that it must be a psycher because it needs to follow the light of the astronomican.

That one was mentioned only three times in this thread so far... cool.gif