Reading a subsector - Regina

[tbeard1999]

No, the part of canon that supports your notion is where it talks about the huge importance of the jump-1 mains. Unfortunately, that part of canon does not fit with the part of canon (the ship-building rules) that says that jump-2 and jump-3 traffic is cheaper than jump-1 traffic for anything more than one-parsec routes. It's almost as if the people who wrote about the jump-1 mains were making things things up out of thin air without considering the ramifications of the ship-building rules.

I ran out a couple of freighter designs (didn't we have this discussion some time ago?) to test your assertions. Both were 1000 ton ships with all spare tonnage devoted to cargo (for simplicity).

Jump-1 ship cost Mcr229.5 and had expenses (not including mortgage) of 310K/month. Carries 684 tons cargo. Cost per ton per jump: Cr1091*.

Jump-3 ship cost Mcr466 and has 584K/month expenses. Carries 469 tons cargo. Carries 469 tons cargo. Cost per ton per jump: Cr3059*.

*Assumed 100% financing of purchase price for 40 years at 5.5% APR (about what the effective interest rate is in Book 2); 2 jumps per month; refined fuel.

Assuming that this is representative, we can draw some very general conclusions about starship economics:

1. CT is completely broken when it comes to balancing starship revenues and expenses (assuming Book 2's revenue model is applicable to commercial operations). No shock there.

2. On a Jump-3 route, the Jump-3 ship delivers a ton of cargo for about the same price as the Jump-1 ship, but the J-3 ship delivers the cargo thrice as fast. So no sane operator would choose a Jump-1 ship for a Jump-3 route, if capital and technology levels are equally available to finance J-3 ships.

3. But the reverse is true of the ships on a Jump-1 route. The J-1 ship delivers cargo for 1/3 the cost per ton as the J-3 ship. So, each route is almost certainly served exclusively by ships with jump drives equal to the jump distance, if the capital and technology is available for the widespread production of J-3 ships.

4. And consider the Book 2 tech limits. Jump-3 drives on a 1000 ton ship require TL 13+, while Jump-1 drives require TL 10+. There's a similar disparity with other hull sizes (less so as the hull gets smaller). So, all but the smallest Jump-3 starships will typically be 1-3 tech levels higher than their J-1 counterparts. In Book 5, Jump-3 is TL12+, while Jump-1 is Tl9+.

5. Much smaller Jump-3 ships are staggeringly inefficient (a 200 ton J-3 freighter delivers a ton of cargo for a cost of Cr7551 per jump, while its J-1 counterpart delivers a ton of cargo for Cr967 per jump). So most smaller ships will be lower jump ships.

In such a situation, I think that Jump-1 "mains" are quite reasonable to postulate so long as there are decent trade relations between each world and at least one other world within 1 jump-1.

 

[tbeard1999]

One of the things I like to do as a GM before I start a campaign is an activity I call "reading a subsector".

Well done, sir. <Golf Clap>

 

[jawillroy]

Well done, sir. <Golf Clap>

Hear hear! Bully, very bully! :applause:

I've been doing a lot of "Subsector Reading" for MpTU, and it's been pretty satisfying. That's actually my primary mode of Traveller play these days.

tbeard, one thought on the ship-profitability thing, which I don't know that I've seen (though I can't imagine there's anything new under the sun for this discussion.) It's obvious that small time merchants and trading companies must finance ships via loans or accept subsidies. But when lines get bigger - to the corporation level, not to say the megacorporation level - does it make sense for them to mortgage their ships? It seems more likely to me that they'll be paying the shipyards directly. Using the LBB2 loans, a 100 Mcr ship ends up costing 220 Mcr. But MultiMega Shipping and Chiseling LLC might well plop down 20% on a new ship, and pay the remaining 80% on a weekly basis over the year or so of construction. If they're a regular customer at the port, they might even get a discount. In any case, the ship will be owned free and clear, and will pay for itself much more rapidly than if it were saddled with a loan.

I'd cobbled together a jump 2 freighter in a standard 400 ton hull; I'd pared it down to 113.5 Mcr. Loan payments came to cr.472,917; even though the ship was tailored for a specific route and virtually guaranteed to run full, if it didn't get very lucky with speculation the ship would go completely bust in no time. If a corporation were to pay up front for the ship, just going with paid cargo and passengers, the ship would pay for itself in about 30 years, rather than 40. Chances are that the company would be shipping its own goods for sale, and would be making considerably more money than by hauling paid cargo - so it would be done even quicker.

So while I'd say most PCs certainly can't swing that kind of deal, it does suggest to me how the bigger corps might fill their fleets, and make the long jumps pay.

 

[rancke]

I ran out a couple of freighter designs (didn't we have this discussion some time ago?) to test your assertions. Both were 1000 ton ships with all spare tonnage devoted to cargo (for simplicity).

What rules did you use? Do me a favor and send me a copy of your ships and your calculations at 'ranckeATdiku.dk' (substituting '@' for 'AT'). Or post them here, if you prefer.

Jump-1 ship cost Mcr229.5 and had expenses (not including mortgage) of 310K/month. Carries 684 tons cargo. Cost per ton per jump: Cr1091*.

Jump-3 ship cost Mcr466 and has 584K/month expenses. Carries 469 tons cargo. Carries 469 tons cargo. Cost per ton per jump: Cr3059*.

*Assumed 100% financing of purchase price for 40 years at 5.5% APR (about what the effective interest rate is in Book 2); 2 jumps per month; refined fuel.

I assume 35 jumps per year for regular traffic, but that shouldn't change the relative results. I used 600T QSDS designs. That would make a bit of difference, but is shouldn't be enough to make that big a difference.



Hans

 

[far-trader]

I assume 35 jumps per year for regular traffic...

That's rather a big assumption there isn't it? Or a typo. The "regular" traffic rate is 25 jumps per year.

So let me ask what rules are you using?

Using a 364(?) day Imperial year, with 14 days out of business for annual maintenance, makes each of your 35 jumps a 10 day trip. Taking out 7 days for an average jump and in system travel leaves you just 3 days on each world to conduct business. Do you really think that is enough time? Or are you talking solely about scheduled route service and not tramp traders?

 

[rancke]

That's rather a big assumption there isn't it? Or a typo. The "regular" traffic rate is 25 jumps per year.

So let me ask what rules are you using?

The regular traffic rate for free traders is 25 jumps per year. It is my opinion that extending that to likewise apply to regularly scheduled traffic is an untenable assumption.

Using a 364(?) day Imperial year, with 14 days out of business for annual maintenance, makes each of your 35 jumps a 10 day trip. Taking out 7 days for an average jump and in system travel leaves you just 3 days on each world to conduct business. Do you really think that is enough time? Or are you talking solely about scheduled route service and not tramp traders?

I'm talking solely about scheduled route service, because I believe that scheduled route service is what establishes the baseline against which tramp merchants operates. Someone has to buy the ships from new that tramp captains buy 40 years later; I just don't believe that a bank will give a loan to someone whose business plan is "I'll jump around semi-randomly and try to pick up the scraps the regular companies miss."


Hans

 

[far-trader]

Got it. All well reasoned and about what I figured out too. Just wanted to clarify that it was schedule route service.

While J1 ships can make money under Book 2 rules without speculating at 25 trips a year, anything J2 and higher has to be subsidized, bought outright, operated differently, and/or built with Book 5. I'd just never really thought about the route schedules much. Your 35 trips looks to work quite nicely for that. Thanks.

 

[rancke]

I ran out a couple of freighter designs (didn't we have this discussion some time ago?) to test your assertions. Both were 1000 ton ships with all spare tonnage devoted to cargo (for simplicity).

Jump-1 ship cost Mcr229.5 and had expenses (not including mortgage) of 310K/month. Carries 684 tons cargo. Cost per ton per jump: Cr1091*.

Jump-3 ship cost Mcr466 and has 584K/month expenses. Carries 469 tons cargo. Carries 469 tons cargo. Cost per ton per jump: Cr3059*.

*Assumed 100% financing of purchase price for 40 years at 5.5% APR (about what the effective interest rate is in Book 2); 2 jumps per month; refined fuel.

Here are my HG designs for a jump-1 and a jump-3 freighter:

1000 T Jump-1 freighter
-----------------------

                  Tonnage         Cost (MCr)

Hull              1000 T           100
Bridge              20 T             5
Computer 1           1 T             2
Maneuver 1          20 T            30
Power Plant 1       10 T            30
Jump drive 1        20 T            80
Jump fuel          100 T             0
Power plant fuel    10 T             0
5 staterooms        20 T             2.5
Cargo space        809 T
----------------------------------------
                                   249.5
Crew
                 Salary
Pilot             6,000
Navigator         5,000
1st Engineer      4,400
2nd Engineer      4,000
Medic             2,000

Yearly expenses:

Crew salaries (12 months):           256,800
Crew life support (50 weeks):        250,000
Jump fuel (35 jumps):                385,000[1]
Power plant fuel (12 months):         13,200
Yearly maintenance:                  249,500
Berthing fees:                         3,500
Loan payments and profit:         15,539,750[2]
-----------------------------------------------
                                  16,751,750

Yearly freight carried: 25,483.5 T[3]

Cost per ton of freight moved: Cr657.36/jump = Cr657.36/parsec


1000 T Jump-3 freighter
-----------------------

                  Tonnage         Cost (MCr)

Hull              1000 T           100
Bridge              20 T             5
Computer 3           3 T            18
Maneuver 1          20 T            30
Power Plant 3       30 T            90
Jump drive 3        40 T           160
Jump fuel          300 T             0
Power plant fuel    30 T             0
6 staterooms        24 T             3
Cargo space        533 T
----------------------------------------
                                   406.0
Crew
                 Salary
Pilot             6,000
Navigator         5,000
1st Engineer      4,400
2nd Engineer      4,000
3rd Engineer      4,000
Medic             2,000

Yearly expenses:

Crew salaries (12 months):           304,800
Crew life support (50 weeks):        300,000
Jump fuel (35 jumps):              1,155,000[1]
Power plant fuel (12 months):         39,600
Yearly maintenance:                  406,000
Berthing fees:                         3,500
Loan payments and profit:         25,375,000[2]
-----------------------------------------------
                                  27,583,900

Yearly freight carried: 16,789.5 T[3]

Cost per ton of freight moved: Cr1,642,93/jump = Cr547.64/parsec

[1] I'm assuming a regularly scheduled freighter can procure fuel at Cr110 per
    ton. That's 100/ton for unrefined fuel plus the cost of refining it if you
    own a fuel purification plant. 
[2] 6.25% per year.
[3] Assuming 90% utilization of capacity.

I did similar designs for jump-2, 4, 5, and 6, and the results were:

True cost of moving freight by starship (HG rules):

Ship       Per jump      Per parsec

Jump-1     Cr657.36        Cr657.36
Jump-2   Cr1,064.84        Cr532.42
Jump-3   Cr1,642,93        Cr547.64
Jump-4   Cr2,657,64        Cr664.41
Jump-5   Cr4,737,36        Cr947.47
Jump-6  Cr10,837.88      Cr1,806.31

As you can see, jump-2 and jump-3 are almost equally cheap and both are significantly cheaper than jump-1. Jump-4 is competitive with jump-1 on price and far better in terms of time.

Note that if you eliminate the ridiculous power plant fuel tanks, jump-3 becomes slightly cheaper than jump-2, but not significantly so.

4. And consider the Book 2 tech limits. Jump-3 drives on a 1000 ton ship require TL 13+, while Jump-1 drives require TL 10+. There's a similar disparity with other hull sizes (less so as the hull gets smaller). So, all but the smallest Jump-3 starships will typically be 1-3 tech levels higher than their J-1 counterparts. In Book 5, Jump-3 is TL12+, while Jump-1 is Tl9+.

The OTU hasn't been a Book 2 universe since High Guard came out. Sure, Book 2 designs was grandfathered (a very bad decision, IMO), but Book 2 and Book 5 designs are not actually compatible; they would not exist in the same universe unless by referee fiat.

That said, jump-3 drives do require TL 12, so they would, indeed, be 3 TLs higher than J1 ships. But so what? There are enough TL12+ worlds around to build and service all the J3 ships you need.

5. Much smaller Jump-3 ships are staggeringly inefficient (a 200 ton J-3 freighter delivers a ton of cargo for a cost of Cr7551 per jump, while its J-1 counterpart delivers a ton of cargo for Cr967 per jump). So most smaller ships will be lower jump ships.

Smaller J2+ ships are indeed at a disadvantage if you accept the minimum bridge size of 20 T. So, yes, a disproportionate number of small ships may well be jump-1. The question is, how many would that be in absolute terms? If a J3 route has traffic enough to support six 200 T jump-1 ships, it would have traffic enough to support one 1000 T J3 ship instead, and that ship would be able to out-compete them.


Hans

 

[mike wightman]

The Traveller Adventure, 1983, is a book 2 universe

Or at least every ship example is built using LBB2, HG is in the background with the meson gun plot.

 

[rancke]

The Traveller Adventure, 1983, is a book 2 universe

Or at least every ship example is built using LBB2, HG is in the background with the meson gun plot.

I'm very fond of TTA and consider it a great book, but it's not perfect. Still, I take your point. Let me amend my statement: The OTU ought not to have been a Book 2 universe after HG came out, since logically it superseded Book 2. Unfortunately, the authors of the day didn't give much thought to exploring the logical ramifications of the facts they established about the background. I'm not even going to blame them for that. It was a long time ago and universe-building probably wasn't even a concern for them.

It seems to me, however, that this doesn't mean that ignoring the logical ramifications of the things that has been established about the background is something to strive for. At the very best you could say that it doesn't do any harm to ignore them. In my opinion it does hurt, but even if it didn't, wouldn't it still be even better if these details actually fit together?


Hans

 

[mike wightman]

It would be much better.

I wonder why the designers didn't decide to base ship building in the revised version of CT, the Traveller Book and starter edition on High Guard 2?
It would have been fairly simple to use a cut down version of High Guard for the basic ship building rules.

 

[aramis]

Probably because damage in Bk2 is tied to drive letters...

Hunter flirted with replicating the effect of this in T20 (somewhere around draft 12... of 23) by making hits in X ton increments.
JDrives would be 5 ton
MDrives 2 ton
PP 4 ton
(Armor could thus be 1:1 ton, staterooms 1 per 20 ton, bridge 1 per 20 ton, etc)
Cargo and fuel were 1h:10ton
It worked really well for PC Scale ships, and up to about 2000 Td...

 

[PFVA63]

Hi, I kind of disagree...

Book 2 and Book 5 designs are not actually compatible; they would not exist in the same universe unless by referee fiat.

Hi,

I kind of disagree with this. My view of book 2 and book 5 is more or less that book 2 outlines simple modular type designs with power plants, jump drives and maneuver drives existing in set incremental sizes, while book 5 outlines vessels where these components are more tailored to a specific ship size. However, I don't see any reason why you can't have ships built to different standards and design methodologies operating side by side.

In the present day, for example, ocean going merchant ships are typically built and maintained in accordance with rules set forth by any one of several Non-Governmental Organizations called "Classification Societies".

When a ship is designed, built, and maintained in accordance with the rules set down by one of these Societies they are noted as being "In Class" which more or less serves as an indicator to anyone wishing to ship their cargo or charter the ship that this vessel is a safe risk.

In general alot of these rules are based on semi-empirical equations and past experience, etc and they provide guidance on minimum plating thicknesses, stiffener size requirements and the like (typically referred to as a ship's scantlings). However, typically these Classification Socieities make the allowance, that if a ship designer wishes to provide alternate calculations and analyses to the Classification Society validating the adequacy of alternate scantlings for the ship's intended service, the Society will take these calcs and such into consideration and may allow for different scantlings than those stipulated directly by the equations in the rules.

As such, in the present day you can easily have two ship's operating side by side, one conservatively built to a Classification Societies basic rules and the other built with reduced scantlings (and hence potentially reduced weight and improved performance) based on the alternate calcs and analyses.

Similarly, I don't see any reason why a similar situation couldn't exist space faring ships in a Traveller type universe.

Anyway, just some thoughts.

Regards

PF

 

[Supplement Four]

Well done, sir. <Golf Clap>

Hear hear! Bully, very bully! :applause:

TVM, gentlemen!

 

[daryen]

I kind of disagree with this. My view of book 2 and book 5 is more or less that book 2 outlines simple modular type designs with power plants, jump drives and maneuver drives existing in set incremental sizes, while book 5 outlines vessels where these components are more tailored to a specific ship size. However, I don't see any reason why you can't have ships built to different standards and design methodologies operating side by side.

Well, that would be great, except that the Bk2 and Bk5 engines and power plants operate by totally different assumptions:
- Bk2 has large jump drives and dinky maneuver drives.
- Bk5 has large maneuver drives and dinky jump drives.
- Bk2 has power plant fuel usage pegged to its "letter".
- Bk5 has power plant fuel usage pegged to energy output.
- Bk2 has TL prerequisites pegged to drive "letter".
- Bk5 has TL prerequisites pegged to capabilities.

If Bk2 was just a "prepackaged" Bk5, I would agree with you. But it is flat out impossible to package any drives in Bk5 to look anything even remotely close to Bk2.

They are just different.

 

[tbeard1999]

What rules did you use? Do me a favor and send me a copy of your ships and your calculations at 'ranckeATdiku.dk' (substituting '@' for 'AT'). Or post them here, if you prefer.

I ran them out on the fly with the CT Utility, which whips out Book 2 designs, but I did not save them. You can replicate them easily with the CT Utility; here were my assumptions:

1. Used the crew calculated per book 2, with double occupancy staterooms

2. No weapons, no small craft, no other fittings

3. Fuel for 1 jump and 1x4 weeks.

4. Use cheapest hull and computer available.

5. Remaining tonnage is cargo.

I deviated from the normal rules for ship financing and financed 100% of the purchase price. This gives a more accurate assessment of the actual cost of delivering cargo.

In response to another question, the economics don't really change if you assume paid-for ships. In that case, there's still the opportunity cost of tying up the capital by paying the ship off.

 

[aramis]

Daryen: CT fuel PP Fuel is tied to rating and tonnage, not to powerplant letter. A PP-Z in a 500 TD (rating 6 wth much overkill) as a PP-T would... and yes, it's MUCH bigger than equivalent HG fuel.

Mongoose Traveller, however, does tie to PP Letter, at 2Td per PP Letter (A=1, B=2, etc)

 

[far-trader]

...yes, it's MUCH bigger than equivalent HG fuel.

Not always. I forget where the breakpoints are and certainly for small ships you're correct, but not for big ships. Or I misunderstand your use of equivalent.

Fuel for a "factor" 2 powerplant (to power a J2 and/or M2 drive) for a 5000ton ships is:

20tons in B2

100tons in B5

 

[aramis]

True. I think small ship all the time. It's 10pn Td for Bk2.
It's 0.01MPn for Bk5. So 2000 Td is the breakpoint.

 

[PFVA63]

Hi

If Bk2 was just a "prepackaged" Bk5, I would agree with you. But it is flat out impossible to package any drives in Bk5 to look anything even remotely close to Bk2.

They are just different.

Hi,

I wouldn't suspect that they would have to be the same. One way of thinking about it is this - in modern ocean going ships you can have a diesel, gas turbine, steam, or nuclear power plant (or even a combination of the above). In modern automobiles you can have a gasoline engine, a diesel engine, or a hybrid power plant. In modern aircraft you can have jet engines, tuboprop engines, or an internal combustion propeller driven power plant.

In each of these applications, the sizes and weights and fuel consumptions, etc differ, but they all co-exist and are all viable means of propelling a ship, car, or plane.

Just because most modern military and big commercial planes use jet engines does not mean that propeller planes cannot exist nor that an internal combustion/propeller plant should be equal in size, weight, or fuel consumption etc to a jet power plant. They are just different ways of accomplishing similar things.

Anyway, that's more or less how I tend to rationalize it in my view of things.

Regards

PF