[Proto-Traveller] Book 2 Plus (includes smallcraft)

[aramis]

Hi Aramis,

Could you break the logic for the above out for me? Thanks!

The cost to operate a HG designed vessel as a cargo ship has three major variables: TL, Size of ship, and jump drive. Smaller ships are more expensive to operate per cargo ton carried (even though the ship is cheaper, the minimum bridge tonnage and computer, plus minimum crewing, make bigger ships more effective). Faster ships are more expensive per cargo ton carried (because fewer tons are able to be devoted to cargo and the non-cargo systems cost more). Lower TL ships cost more per cargo ton carried (because the PP is larger, and thus less cargo can be carried, as well as the fact that they're priced per ton).

A Bk5 designed ship cannot make money at Cr1000 per cargo ton until TL13 at 200Td, or 400Td at TL9... because the 200Td TL9 costs Cr1018/Cargo Ton to operate. The minimum cost per cargo ton for J3 is Cr1655 per ton (At TL15, 50KTd, J3 M1 P3); at 100Td, TL12 J3, that's Cr11213/Td....

Now, for Bk2, it's cheaper.. J2 shipping at 3000Td-5000Td hulls can make a profit.
J3 needs 1107 per td at 4000Td.


Note that if that is Cr1000 per parsec, rather than per jump, nothing† moves J3 until TL15 under HG, and that in big (20KTd+) freighters.

Under Bk2 at Cr1000 per parsec, J6 can haul profitably (but only in the 3000Td hull; in CT 2E, only the 2000 and 3000 Td can make J6, while in CT 1E, the 400, 600, 800, 1K also can non-profitably make J6).

But note also - no J2+ merchantmen appeared in Traveller core rules until 1983, with TTB. Under CT core rules, speculation can make up for the difference in op costs and use freight loads to fill out. J3 can only work for passengers and only on subsidy lines except for the "big haulers" of 3000Td - who can potentially speculate for J6 successfully if not on fixed routes.

So, in the end, the Bk2 universe is a VERY and VASTLY different place than the OTU.

†except speculation

 

[boomslang]

Now, I find I don't mind it nearly so much... but would rather it have been fuel by drive letter and the same number of steps per TL...

The implicit TL constraint of the B2 drive table produces some non-trivial wide-ranging results. At TL11, you end up with what I label the "Type K galleon" -- a drives-K, 1000dton, J-2 platform with ~60% (600dtons) of payload space. This basic frame becomes the backbone of all interstellar shipping and military logistics until you reach all the way up to TL15 and drives-V become available; even then, the four-TLs-lower Type K never really becomes obsolete.

I also long ago adopted Thomas House's EP structure for B2 powerplants, to measure actual/operational, versus ruled/regulatory, fuel requirements. That and per-parsec carriage rates are the two main House Rules IMTU to make B2 acceptable.

 

[aramis]

The implicit TL constraint of the B2 drive table produces some non-trivial wide-ranging results. At TL11, you end up with what I label the "Type K galleon" -- a drives-K, 1000dton, J-2 platform with ~60% (600dtons) of payload space. This basic frame becomes the backbone of all interstellar shipping and military logistics until you reach all the way up to TL15 and drives-V become available; even then, the four-TLs-lower Type K never really becomes obsolete.

I also long ago adopted Thomas House's EP structure for B2 powerplants, to measure actual/operational, versus ruled/regulatory, fuel requirements. That and per-parsec carriage rates are the two main House Rules IMTU to make B2 acceptable.

Adding EP isn't all that useful....

Per Parsec makes Bk2 rather reasonable. Remember, tho' - all the canon pre-HG merchants are either J1 or subsidized... and a subsidy makes even J3 almost reasonable. The largest expense is the monthly payment. Fuel is #2.

 

[boomslang]

Adding EP isn't all that useful....

If you let them consume fuel at that rate, however, it significantly extends operational duration for a full load, or alternately, you can re-purpose some PP fuel and get another parsec or two of Jump fuel in some scenarios.

Oddly, nothing in B2 states that powerplants consume fuel at the rate of 10Pn/fortnight, only that such a required load is "sufficient" to support 4 weeks of operations.

Which, below TL15 and the largest B2 drives, is true either way you interpret the requirement and burn it.

Also, Powerplant-A putting out only 2 EP explains neatly why you never see more than two lasers mounted on a non-B5 Type S in canon...

 

[Matt123]

[FONT=arial,helvetica]in book 3, the required TL for drives of specific sizes is mentioned on the TL table...[/FONT]

I had not made that connection before!

At TL 12 the best jump range you can get is J5 in a 400tn ship (Fast Fleet Courier, rather than merchant).
Bridge: 20tn
Model 5: 5
JD K-drive: 55
MD B-drive: 3
PP K-drive: 31
Fuel power: 50
Fuel jump: 200
crew x5: 20
TOTAL: 384 (leaving 16 ton for payload)

Essentially at (TL12);

• 400tn you get J5,
• 401-600tn you get J4,
• over 600tn you get J3 (by being selective as to which engineering system you use).

This is much better than my previous understanding --- that Bk2 flat out enabled J6 ships well before their time.

 

[boomslang]

At TL 12 the best jump range you can get is J5 in a 400tn ship (Fast Fleet Courier, rather than merchant).

Actually, note that drives-K and the Model/5 come in at TL11, the bottom end of "Average Imperial".

But the exorbitant B2 fuel requirements put Jump-6 off until TL14 at the earliest... you cannot build a hull small enough for the drive efficiency yet big enough for all the required fuel until then -- and it ends up being a tight squeeze even at that point; TL15 is pretty much a requirement for a B2 Jump-6 ship to be worth the build cost and still have anything resembling a "payload capacity".

 

[Matt123]

But the exorbitant B2 fuel requirements...

Just thinking aloud, it could easily be explained by a change in the technology used as the use case changes. Militarized versions of technology are fairly well accepted as a double standard to suit a different use case - despite being more expensive and often less efficient.

A Free Trader under Bk5 gains ~9 tons of space, but costs about 50% more than a Bk2 design. You want cheap capital costs, use the crappy inefficient PP over there. You want long range, efficiency and price is not a consideration, have I got a deal for you!

 

[aramis]

Actually, note that drives-K and the Model/5 come in at TL11, the bottom end of "Average Imperial".

But the exorbitant B2 fuel requirements put Jump-6 off until TL14 at the earliest... you cannot build a hull small enough for the drive efficiency yet big enough for all the required fuel until then -- and it ends up being a tight squeeze even at that point; TL15 is pretty much a requirement for a B2 Jump-6 ship to be worth the build cost and still have anything resembling a "payload capacity".

The pre-81 Bk2 it's far less an issue.

A 400Td J5 needs

CT 77	Item	CT 81
020	Bridge	020
200	JFuel	200
010	Fuel	040
007	PP B or K	031
003	MD B	003
055	JD K	055
020	Crew SR (5/6)	024
002	Model 2bis/5 (5/6)	005
083	payload	022

Note that under CT-'77, you need a Model 4 or a model 2bis to run Navigate and Jump5 at the same time (which is required). (A model 3 won't cut it).

So, a 2bis 200 Td J5... under CT 77
020 Bridge
002 Model 2bis
100 JFuel
030 JD E=5
004 PP A=1
001 MD A=1
016 Crew (PNEM)
010 Fuel, PP 1
017 Payload

Plenty serviceable for a J5 courier, and TL 10.
Going to CT-81, increase to PPE (takes +55 Td... and can't be done; +12 PP, +40 Fuel-PP, and +3 computer).

Real Prototrav should be using pre-81 CT...

 

[salochin999]

Hi Aramis,

Could you break the logic for the above out for me? Thanks!

There is another option if you want your Imperium (or version thereof) to be darker if you also stipulate that most ship construction is in the hands of the noble families as it effectively forces merchants into the Book 2 subsidized merchantman model. Following the consequences of this can lead to some interesting scenery.

(As part of the subsidized merchant deal is the ship automatically becomes part of the merchant marine during wartime that is another non-monetary reason for the Imperium to impose it.)

Either alternative has another aspect also which is second hand ships. If a ship has been paid off it suddenly becomes a money fountain which I assume would be gradually balanced out by increasing maintenance costs per year

(If the monthly repayments are 1/240 then the repayments are 1/20 base cost over a year. Maintenance is 1/1000 base cost a year. Say you increase maintenance costs by an extra 1/000 per year it would take 50 years before it reached the same level (1/20) of base cost as the initial loan repayment (perhaps also with some chance of catastrophic failure in one of the components needing complete replacement). Alternatively if you increase the increase in maintenance costs over time in some way then maybe the ship has 20-30 years when it is very profitable.)

Whatever the numbers the general pattern should be obvious - the carrot for wannabe merchants is the grail at the end where the ship is a money fountain for some number of years.

This would create a second hand market and some alternative ways of running a trading game i.e. ships that are paid off but falling apart.

 

[boomslang]

So, a 2bis 200 Td J5... under CT 77
020 Bridge
002 Model 2bis
100 JFuel
030 JD E=5
004 PP A=1
001 MD A=1
016 Crew (PNEM)
010 Fuel, PP 1
017 Payload

Plenty serviceable for a J5 courier, and TL 10.
Going to CT-81, increase to PPE (takes +55 Td... and can't be done; +12 PP, +40 Fuel-PP, and +3 computer).

Real Prototrav should be using pre-81 CT...

I do not have my dilapidated old 1e B2 to hand at the moment, but under the original rules, are Navis still required on 200-dton vessels, or only on over 200-dton vessels (as per the '81 edition)? You might be able to save another 4dt if the latter is the case.

Now, if we can only figure out why Xboats did not pack M-drive-A and P-plant-A and 10dt of fuel to get around on...

:CoW:

 

[mike wightman]

Because the x-boat uses a standard hull which only has drive space for 15t of drives which just happens to the size of a jump B drive.

 

[atpollard]

Interesting, isn't it, that both the Type S and the X-boat use a "standard" 100 dTon hull with 15 dTons of 'Engineering' and 85 dTons of 'everything else'.

... the far future must have a different definition of a 'standard' hull than I do.