Size of Traveller starships

First, let me say I'm not a fanboy. I could give a hoot about TV-show or movie spacecraft. However, I grew up on Traveller and while I can't enjoy it as an RPG anymore, the universe and theory interest me greatly in my spare time. That being said:

Traveller hull armor (and all ship structural material) is by necessity many orders of magnitude stronger than titanium steel. I postulate carbon-pressed superdense has a tensile strength of around 75 GPa and a hardness of about 16K on the Moh's scale, or 10 times harder than diamond. It's melting point (at least for the exterior hull) would need to be approximately 100,000 degrees K. Superdense would be manufactured to order in preformed panels and therefore cannot be customized or modified- ships with damaged hulls can be patched with carbotronex, a lighter material that can be softened and molded to shape before being treated with heat and an electrical current to stabilize the crystal structure. Once hardened carbotronex has properties orders of magnitude weaker than superdense, but still sufficient to survive most light-duty spacecraft operations. Carbotronex is essentially a electrically-conductive polymer epoxy that allows the current from the ship's hull-strengthening jump grid (or whatever passes for it in non-jump ships) to pass through it. Carbotronex would have a melting point far below that of superdense and it would be structurally weak by comparison- flexible and tough but far less hard, yet sufficient to allow re-entry, fuel-skimming and interstellar maneuver, but not sufficient to resist combat damage.

With this in mind, the power of starship weaponry, powered by even the smallest ship's reactor, must be awesome. A ship-borne 500MW laser or fusion gun would vaporize a modern MBT tank in one shot. Nothing in Striker's ordinance list would come close to the power of a starship weapon. Even a battlefield meson accelerator would be puny compared to the smallest starship meson weapon. But then again, the battlefield reactor would be a fraction of the size and very possibly require capacitors to charge before firing, unlike a starship. Moreover, starship weapons operate at ranges of light-seconds (i.e. hundreds of thousands of kilometers). Keep this in mind when factoring the damage multipliers. Then again, the deep meson gun site that protects planets would be even more terrifying- it would be the doomsday weapon on any world, capable of ending any battle in space or on the surface in one shot. But I digress...

The hull material postulate above is based on a rationalization of the parameters required for orbital re-entry, high-inertia maneuver and, most importantly, resist the impact of spaceborn debris. WithTraveller spacecraft, even a 1-G ship, can approach the speed of light in about a year and velocities for higher-G ships can be quite significant. Even the smallest micrometeroid could obliterate a spacecraft that had travelled in from the Oort cloud at high-G - and Traveller ships are supposed to be able to maneuver at high-G, even more immensely-stressful. Therefore, hull material for even a commercial ships would be astronomically powerful. This doesn't scramble Traveller tech much- efficient fusion power requires materials with similar strengths- it just assumes the gravity technology that permits antigrav propulsion and jump drive includes a lot of benefits we don't understand today, such as how to enhance the strong nuclear force in materials, though with fixed and predictable (i.e. preformed, uniform crystalline structure) matrices. These are well within the Einsteinian realm.

Presumably the armor in tv-movie ships would be even more powerful, given their higher-g capacity, but even they are done for the cameras- 6-g would be more than sufficient acceleration for any warship. The limits in Traveller seem arbitrary but I've always pegged them to the limits of inertial compensation, another critical (indeed, indispensable) technology, without which a spacecraft with greater than 1-G acceleration isn't even really practical.

Keep in mind the Traveller universe, even with its apparent limitations, includes the common, everyday and miniaturized use of fusion power, at temperatures in the millions of degrees and without messy radiation. To be practical, the understanding of high-strength materials would have to leap exponentially at TL9, to the point that we can't really conceive of the advances and can only place labels on things that could be lumped under the catch-all "unobtanium".
 
Thasaidon said:
Traveller hull armor (and all ship structural material) is by necessity many orders of magnitude stronger than titanium steel.
I doubt that, because the values for different materials given in the va-
rious versions of Traveller do not really support it. Stronger, of course,
but far from what I would see as "many orders of magnitude". For ex-
ample, in Fire, Fusion & Steel for TNE the Toughness value of Titanium
Alloy is 3, while the one for TL 12 Superdense is 14.
 
Thasaidon said:
and a hardness of about 16K on the Moh's scale, or 10 times harder than diamond.

Mohs scale is a ordinal, not linear. A is harder than b is harder than c. It does not quantify the hardness, so superdense could actualy just be 11 on the scale, simply because it is harder than diamond at 10. Also, Mohs scale is restricted to minerals, not composites.

Nice article on testing hardness here: http://www7.taosnet.com/ebear/metal/hardness.html

G.
 
Superdense is at the top of the Moh's scale- there are intermediate materials (carbon fiber, ceramics, crystaliron) used for hull material prior to its introduction. The value is a relative metric to indicate the hardness relative to other materials, not an industrial specification. The important thing is that superdense is incredibly resistant to even the smallest scratch because it's a crystalline structure (an evolution of the crystaliron technology using carbon in lieu of iron). Not only is it incredibly scratch-resistant, but it's also flexible, allowing it to flex slightly to absorb shock and resist shearing.

Material rules are the ordinal values, if anything - to say superdense is incrementally stronger than titanium alloys is highly unlikely. Titanium steel is not remotely strong enough for a starship hull that's designed for unlimited maneuver in space- which is why it gets dumped around TL6 in favor of ceramics and carbon composites. Ceramics lead to crystaliron as the pinnacle of the former use a controlled crystalline structure for the latter. Gravity manipulation leads to collapsed matter, but superdense is not a malleable material. It has to be preformed in panels. In any case, starting at TL9 the hull of a starship isn't forged and hammered into shape by a blacksmith, it's fabricated in sections that can never be permanently modified without destroying the integrity of the panel and requiring a shipyard to replace it. The interlocking panels are presumably small enough that they can be replaced in small increments. The main point is you can't modify the interior frame of a and you can't modify the exterior hull without permanently damaging that section in the field- you need a shipyard (or equipped mobile fab facility) capable of producing the correct materials.
 
Thasaidon said:
Titanium steel is not remotely strong enough for a starship hull that's designed for unlimited maneuver in space- which is why it gets dumped around TL6 in favor of ceramics and carbon composites.
In the Traveller technology titanium alloys usually become available with
TL 6 and are never dumped, they remain in use until at least TL 15 as one
of the options for the construction of starships.

Besides, a material strong enough for the hulls of submarines that opera-
te under the pressure of the deep sea and jet fighters that perform ma-
neuvers significantly beyond a 6 G acceleration limit can be expected to
be strong enough for the hulls of starships.

As for micrometeorites and thelike, no known or plausible fictional hull
material could provide a reliable protection against high speed impacts -
even Niven's hypothetical Scrith from his Ringworld novels got holed ...
 
The problem, as i understand it, with really big ships is of structural ridgidity (is that a word?). You can have a kilometer long starship, with hyper-thrust engines, but the thrust required to move the ship applys forces that the structure can't handle. The image I have seen is of ship collapsing like a prtly inflated dirigible as thrust is applied, simply because the structure can't support it's own mass - the drives tear their way out of the ship as the structure fails around them, or the ship collapses onto itself.

Of course, assuming sufficently advanced materials technology, I guess you can spread the stress around. Star Trek had the "Structural Integrity Field" that bolstered the... structural integrity.. of the ship. Whenever the structural integrity field failed, bad things happened.

Personally I prefer the small ship paradigm, partly because my introduction was via 2300AD where big ships were rare.

G.
 
rust said:
Thasaidon said:
Besides, a material strong enough for the hulls of submarines that opera-te under the pressure of the deep sea and jet fighters that perform ma-neuvers significantly beyond a 6 G acceleration limit can be expected to be strong enough for the hulls of starships.

Actually, not even close. Such hulls wouldn't survive even hitting dust at listed MGT interplanetary travel speeds. Them's the rules.
 
rust said:
As for micrometeorites and thelike, no known or plausible fictional hull
material could provide a reliable protection against high speed impacts -
even Niven's hypothetical Scrith from his Ringworld novels got holed ...

In Niven's works I recall the Puppeteers having near impevious hulls - the infamous General Products Hulls?

According to Wiki:

The Puppeteers' renown for honesty in trading allowed the species to accumulate an expansive mercantile empire called General Products; since the human Bronze Age, the Puppeteers have ruled this empire including every race in the 60-LY sphere of Known Space. After the Puppeteer Exodus (see below), it is rumored that General Products is a front for Gregory Pelton, a character in the short story "Flatlander". One of the most important items sold by General Products is the General Products Hull for spaceships. As one might expect from a Puppeteer, such a hull is completely impervious to everything except visible light (defined as visible to any of the species who are General Products customers), tidal forces and gravity, and obliteration by antimatter. The hulls are advertised as being capable of flying through the upper atmosphere of a star unscathed, although the contents will be cooked; as a protection against this particular contingency, the Puppeteers also provide a stasis field.

Exposure to antimatter is the only known method for destroying a General Products hull until the recent novel Fleet of Worlds. In the story Flatlander, a GP Hull is exposed to a constant stream of diffuse antimatter during a visit to a star system with some exotic qualities. Whereas a conventional hull made of metal, for example, would simply have ablated under these conditions, the General Products hull instead simply unravelled. This was due to the fact that a GP Hull essentially consisted of a single incredibly large, highly complex molecule. Once a sufficient number of the atoms which constituted the molecule were annihilated by the antimatter, the molecule could not remain stable, and thus degenerated into a selection of less complex compounds and elements, effectively causing the hull to vanish in an instant. Fortunately, the vessel's pilot was sufficiently cautious to be wearing a vacuum suit at the time, and survived, as did the owner of the ship.

In Fleet of Worlds, the characters tour a General Product factory and ask innocent-seeming questions of their tour guide, Baedeker. Baedeker reveals (apparently unintentionally) that the manufacturing process is extremely sensitive to gravity and impurities, that the hulls are constructed from a single super-molecule constructed using nanotech, and their strength is reinforced by an embedded power plant that reinforces the inter-atomic bonds. These facts provide the clues that allow them to later destroy a GP Hull from the inside and survive.

In Destroyer of Worlds, a captured Pak Protector analyzes the hull, deducing that it comprises a dynamically reinforced molecular structure and how to syphon energy from the structure.
 
apoc527 said:
I know that Traveller is supposed to be less space opera-y and that 1.6 km long Star Destroyers are perhaps a little too unrealistic, but don't Traveller ships strike you as being really rather puny?

Maybe the more massive ships are just less powerful? Too many sci-fi universes to choose from! What a world!... What a world!

I think the Eagle from the 'Space 1999' TV Series and the Discovery from "2001" look very odd next to each other. One of them has to be off-scale.
 
Back
Top