Most Efficient Ship by TL for Cargo to X Parsecs

[Grav_Moped]

Because they did not playtest it enough? Because they did not care?

My long-standing theory: In the LBBs, Traveller starships appear to be originally conceived of primarily as a mechanism of convenience for transporting mercenaries and the criminally-inclined between the starports of mainworlds so that they may further their post-service careers of "misbehavior"; any other use -- mercantile activity, exploration, prospecting & mining, pleasure cruises, and what have you -- was considered incidental to the intended gameplay and was therefore relatively neglected in the design and operations rules.

Have you compared the standard hulls to the 1977 B2 design process, wherein power plants need only match M-drives, and J-drives are not constrained by power plant model? Left as an exercise for the reader...

I don't have a copy of the '77 rules, alas.

"Didn't care" is close to my take on it. More to the point, I suspect that all of the standard hulls worked for specific sets of drives in the first edition, but they only changed the ones that directly affected the ships in LBB2 for the second edition.

And the trade rules' cargo rates weren't meant to provide a profit, just to provide revenue-generating stuff to pack in around the profitable speculative cargo to fill the cargo hold. The spec cargo is where the big money is, and it's risky so it's fun. (Hauling generic ISO containers around is boring unless the ref steps in and makes those ISO containers interesting.)

And, yeah... ships were either location sets or how the PCs get from one encounter to the next. If you flew a Trader, that was the pretext for adventures -- the mundane bookkeeping aspects weren't the adventure in and of themselves. "Close enough" was supposed to be good enough.

I'm just trying to take "close enough" and build a halfway coherent trade system out of it. Or at least analyze the economics underpinning shipping costs.

 

[kilemall]

I disagree with the characterizations here about the trade game being 'sloppy' and a backseat backdrop to going onto the next crime/merc job. I think they had an entire progression designed into the ship rules so you would always be chasing that next goal. The computer rules are central to this process, as are the bulk cargos leading to getting speculative cargo stakes and going on up the chain to more powerful programs and armament and doing mail runs.


All leading to getting the down payment or better yet speccing (and buying without a loan) that sweet custom hot rod with near as much programming cost as the ship itself.

 

[Straybow]

The drive potential table is mostly consistent, with a couple of odd jumps (Z Drives being the most obvious, but I remember finding a couple of non-linearities when I manually graphed size vs. performance back in the early-mid 1980s. The non-linearity might have been partially for copyright reasons (formulae can't be copyrighted, while a chart that wasn't generated by a formula can be -- yes, I know you could write a formula for it, but it'd be more of a function than a formula). And as I understand it, the lack of granularity (particularly above 1000Td) wasn't laziness, it's that they didn't have room on the page for more.

Then why make rules that dictate any tonnage between the table values gets treated as the next larger value? In essence there isn't a 1200 ton hull, it is a 2000 ton hull in performance. There's little point to making anything between 1000 and 2000. Why isn't extrapolation the rule? OK, didn't think of it in the initial printing, so why not make it the rule any time in the last 40 years?


If somebody says, "It would make sense to extrapolate between those values," the response is "Not valid in the OTU, and take your helpful suggestion with you."

 

[Straybow]

My long-standing theory: In the LBBs, Traveller starships appear to be originally conceived of primarily as a mechanism of convenience for transporting mercenaries and the criminally-inclined between the starports of mainworlds so that they may further their post-service careers of "misbehavior"; any other use -- mercantile activity, exploration, prospecting & mining, pleasure cruises, and what have you -- was considered incidental to the intended gameplay and was therefore relatively neglected in the design and operations rules.

Have you compared the standard hulls to the 1977 B2 design process, wherein power plants need only match M-drives, and J-drives are not constrained by power plant model? Left as an exercise for the reader...

No, there would be much less detail in starship design if that were the case. There is a whole lot of unnecessary detail for backdrops and plot devices. A ship would only need to be a sum of parts: Jump-J, Man-M, N staterooms, X tons cargo, Y tons fuel. Plug into a formula, that's how much it costs. OK, throw in simple turrets for that much more, and maybe "shields" or some other std scifi defense. Done. Computer? Anything else not mentioned? Handwave.


No, the "standard design" engineering sections don't match viable engine combinations in '77 rules either. The original 3 LBBs are all I ever had.

 

[boomslang]

No, there would be much less detail in starship design if that were the case. There is a whole lot of unnecessary detail for backdrops and plot devices. A ship would only need to be a sum of parts: Jump-J, Man-M, N staterooms, X tons cargo, Y tons fuel. Plug into a formula, that's how much it costs. OK, throw in simple turrets for that much more, and maybe "shields" or some other std scifi defense. Done. Computer? Anything else not mentioned? Handwave.

Which, to my eye, kind of undermines your point in the first sentence; starship design rules are deliberately minimal in CT and free of granular details beyond basic logistics and combat -- compare the nigh-endless tables of options available in T5 for contrast.

No, the "standard design" engineering sections don't match viable engine combinations in '77 rules either. The original 3 LBBs are all I ever had.

Looking at things like the Lab Ship, my suspicion is that the standard hulls are deliberately designed to produce waste tonnage for any reasonable set of drives one might try to fit in their engineering sections.

BT is implicitly all about herding the PCs in the direction of extra-legal sources of revenue -- and merchants are no exception. Between sub-optimal vessel designs, usurious interest rates on starship mortgages, and obvious price-fixing on shipping and passage rates, even with very, very lucky rolls on the availability tables and a lot of skill at free trading, the rules intend that PCs should be -- again, by design -- unable to make ends meet in the long run, and therefore driven to seek out "side jobs" in order to <ahem> keep flying.

 

[whartung]

Which, to my eye, kind of undermines your point in the first sentence; starship design rules are deliberately minimal in CT and free of granular details beyond basic logistics and combat -- compare the nigh-endless tables of options available in T5 for contrast.

A key criteria for many of the rules in the LBB is a simple one: the rules have to fit in the LBB.

The 3 books are tiny compared to most every other game at the time. Original D&D was clearly a close match, but it moved on to, what, 5 more books, and all they had to cover was char gen, spells, and combat.

In contrast to the toolkit that the LBB provided.

So, no doubt, there were things left out, things over looked, and things "un-designed" for the sake of space and, likely, just to get it out the door.

One thing we know about RPGs in contrast to board games is that, especially early on, the rules were experiential, they're meant to be used as a broad brush and, notably, aren't necessarily meticulously studied, especially for "balance", since "balance" never really enters the equation.

"Balance" in and RPG is enforce by the iron fist of the Referee.

To paraphrase similar sayings: "The LBB are not a suicide pact for the campaign."

Nor are they a hammer to be wielded by the players against the referee.

So, any thing that comes out ill thought, or sloppy, can be assigned to the paragraph in the books that essentially says "just wing it".

Later, as things got more simulationist, the designers lose that presumption of innocence. The more detail there are in the rules, the more the game play is controlled by the rules, so the rules better make sense.

So, it's fair, IMHO, to handwave a lot of whats in the LBB, but the chapters of charts and graphs and differential equations in the later editions, those lose some of that charity and should be held to a higher standard.

 

[Grav_Moped]

...
Looking at things like the Lab Ship, my suspicion is that the standard hulls are deliberately designed to produce waste tonnage for any reasonable set of drives one might try to fit in their engineering sections.

I don't think the waste space was intentional. I do think they didn't "play test" it, in terms of going through all the possible combinations of drives to see what would fit. It took me a while to do it semi-manually with Excel.* They might have checked them for what they didn't want to fit, then set the drive space just below that.

If I'd had to create the standard drives table manually with a hand calculator back in the late 1970s, I'd have just done the minimal "make it small enough that, say, J-4/4G won't fit" check and called it good, myself. (The 100Td/200Td hulls are "fits Size A Drives" so PCs can get a break on entry-level ships.)

BT is implicitly all about herding the PCs in the direction of extra-legal sources of revenue -- and merchants are no exception. Between sub-optimal vessel designs, usurious interest rates on starship mortgages, and obvious price-fixing on shipping and passage rates, even with very, very lucky rolls on the availability tables and a lot of skill at free trading, the rules intend that PCs should be -- again, by design -- unable to make ends meet in the long run, and therefore driven to seek out "side jobs" in order to <ahem> keep flying.

The trade rules aren't that broken if everything moves by J1, which it probably does. While they really should be on a per-parsec rather than a per-jump basis, the first-edition "burn all your fuel each trip" rule skews that a bit, and they didn't fix it in the second edition. I agree that the idea was kind of what you're getting at: you don't get rich hauling ISO containers at Cr1000/Td, you have to use the trade speculation rules if you want to make your fortune. And hauling cargo wasn't ever really meant as the means to an end, but instead to be the pretext for the PCs moving on to the next planet down the line for their next adventure.


* Basically, I replicated the size/cost table by calculating it from the formulae to save transcribing it. (Jump Mass: Size*5+5, Jump MCr: 10*Size. And so on. Size is the ordinal value of the drive letter: A=1, B=2, J=9 because "I" was dropped, etc.) Then I did columns for "jump drive with powerplant" and "manuever drive with powerplant". If the Jn was higher than the Gs, I picked the J-Drive & powerplant and looked for the biggest M-drive that fit the remaining space; if it was the other way around, I picked the M-drive & powerplant and looked for the biggest J-drive that fit (then checked if there was room for fuel).

 

[mike wightman]

If somebody says, "It would make sense to extrapolate between those values," the response is "Not valid in the OTU, and take your helpful suggestion with you."

I made a stab at this years ago - the posts are pretty corrupt now due to board changes changing the formatting and I have never learned to use the table making tools.

http://www.travellerrpg.com/CotI/Discuss/showthread.php?t=10687

 

[boomslang]

So, it's fair, IMHO, to handwave a lot of whats in the LBB, but the chapters of charts and graphs and differential equations in the later editions, those lose some of that charity and should be held to a higher standard.

I find that it is often fairly easy to slot things into CT from later editions; this is why I continue to prefer the minimalist approach of BT, and use T5 mostly for idea sourcing rather than actual play.

 

[Proneutron]

The trade rules aren't that broken if everything moves by J1, which it probably does.

Probably not as not enough worlds are contiguously J1 that match supply/demand based on world types. Most likely J2 is the standard. The intentional J1 design of the Spinward Marches J1 route notwithstanding

 

[boomslang]

The trade rules aren't that broken if everything moves by J1, which it probably does.

Note that there is a huge assumption contained in this generalization about average stellar density of the area in question, though. As robject has said regarding Travelling around default-50%-stellar-density space: "With J-2 you can skip about half of the boring worlds; with J-3 you can skip most of them." Here, for "boring" read "likely to be unprofitable" instead.

OTOH, I have seen entire Rifty sectors out there that are so sparsely-populated (with star systems and/or inhabited planets) they seem to assume everybody is zipping around at J-3, or even J-4. (Or else they are using alternate FTL systems. :CoW Which I personally think is silly; why not just compress the whole sector down into a couple of subsectors, and make the setting just as populated with but a handful of playable worlds without the added logistical and TL hurdles for both the ref and the players?

IMTU, I put some effort into designing subsectors with ubiquitous J-1 mains, specifically to establish a healthy, thriving background of J-1 haulage all over the place.

YMMVIYTU, natch.

[/soapbox]

 

[Grav_Moped]

Jump-1 includes jump-1 ships with tanks for multiple jumps.
Haven't really run the numbers, but 2xJ1 costs about the same as 1J2 so per-parsec pricing works out ok. 3J1 is cheaper than 1J3, so it'd be preferred if you were paying per parsec.

No need to go high-tech. It just takes a lot longer to get around.

Need to work the numbers on doing it with drop tanks for the first jump, internal demountable for the second, and built-in tanks for the third one. But that's a low priority....

 

[boomslang]

Haven't really run the numbers, but 2xJ1 costs about the same as 1J2 so per-parsec pricing works out ok.

Life support cost is the only real discrepancy.

The flip side I can see is that passengers might expect a discount on passage rates for keeping them cooped up an extra week in Jumpspace.

Well, the non-low-passage ones, at least. Low passengers are basically refrigerated freight.

 

[Proneutron]

Need to work the numbers on doing it with drop tanks for the first jump, internal demountable for the second, and built-in tanks for the third one. But that's a low priority....

Naw, just go with collapsible tanks. Ship H2O in them to refine while in jump. Volume is ~60% of the LHyd. So if you need 20 tons of LHyd for the 2nd J1 just ship 12 tons of H2O in the collapsible tanks. When empty, they can be stored at 1% of their full volume.

 

[Grav_Moped]

Naw, just go with collapsible tanks. Ship H2O in them to refine while in jump. Volume is ~60% of the LHyd. So if you need 20 tons of LHyd for the 2nd J1 just ship 12 tons of H2O in the collapsible tanks. When empty, they can be stored at 1% of their full volume.

I'm trying to keep this to LBB2 as much as possible right now, allowing demountable tanks since they're in Beltstrike as well as LBB5. Nice idea, though.

 

[Grav_Moped]

Life support cost is the only real discrepancy.

The flip side I can see is that passengers might expect a discount on passage rates for keeping them cooped up an extra week in Jumpspace.

Well, the non-low-passage ones, at least. Low passengers are basically refrigerated freight.

I'd work it the other way: fares are per-parsec, but there's a premium for being able to do it in one week. High Passage passengers will always pay the extra. Mid-passengers might or might not. Low passengers don't care.

And when I add economy(2Td/pax) and steerage (1Td/pax), there will be limits on how long they can go on a single ticket for multiple jumps. (Economy, 2 weeks; steerage, 1 week).

 

[Straybow]

No, there would be much less detail in starship design if that were the case. There is a whole lot of unnecessary detail for backdrops and plot devices. A ship would only need to be a sum of parts: Jump-J, Man-M, N staterooms, X tons cargo, Y tons fuel. Plug into a formula, that's how much it costs. OK, throw in simple turrets for that much more, and maybe "shields" or some other std scifi defense. Done. Computer? Anything else not mentioned? Handwave.

Which, to my eye, kind of undermines your point in the first sentence; starship design rules are deliberately minimal in CT and free of granular details beyond basic logistics and combat -- compare the nigh-endless tables of options available in T5 for contrast.

You missed the point. I didn't say how big a jump drive was, nor maneuver drive, nor size of staterooms. A ship needn't be more than it's generic capabilities. It could be that simple.

 

[mike wightman]

Naw, just go with collapsible tanks. Ship H2O in them to refine while in jump. Volume is ~60% of the LHyd. So if you need 20 tons of LHyd for the 2nd J1 just ship 12 tons of H2O in the collapsible tanks. When empty, they can be stored at 1% of their full volume.

But according to Another Dilbert we can not fill 14 cubic metres of cargo with water as this breaks the 1000kg limit to what a 14 cubic metre cargo space can hold - if that is inded the argument he was proposing.
I agree with you that if you can fill 14 cubic metres with water then it is a more efficient way to carry spare fuel, but it goes back to the can I pack 14 cubic metres of gold in there instead?

 

[Proneutron]

But according to Another Dilbert we can not fill 14 cubic metres of cargo with water as this breaks the 1000kg limit to what a 14 cubic metre cargo space can hold -

No, he said, "1000 kg/m3" is the nominal mass assumed for a dton of cargo. Which would be 14,000 kg/dton as there are ~14m³ in a dton. Maybe the wording wasn't the clearest.

 

[Condottiere]

I hear that gold is rather cheap; you probably could install eighteen carat toilets and other indoor plumbing features.

And what happens if the passenger brings a thousand kilogrammes of feathers, or something similarly light and bulky?