Most Efficient Ship by TL for Cargo to X Parsecs

[AnotherDilbert]

Nice idea. Not sure I'll use it since it violates the spirit of the rules.

The Gazelle made it firmly canonical.

TCS even introduced a specific type of tank for this type of application: External Demountable Tank, but since it just as expensive as Drop Tanks but not as flexible, I just use Drop Tanks.

My concern, aside from that it violates the spirit of the design rules, is that drop tanks are extremely vulnerable (per TCS). Any single fuel hit destroys all external tankage. Unless the ship retains fuel for a Jump-1 in internal tanks, that's a mission (get cargo to destination) kill, and since these ships are minimally-armed and only 1G, a jump-capability kill is also an adversary victory condition.

Agreed, but they are unarmored transports. If someone really shoots at them, they are dead...

 

[AnotherDilbert]

Oddly, at J-1 none of these ships fit a standard hull. Might show up at Jump-2.

The 400 Dt standard hull is very usable at J-1 and J-2. See my example in post #5. It is cheaper than the 800 Dt example you made for TL-9 and J-1.

 

[AnotherDilbert]

- There is only one turret; triple, with a laser, missile, and sandcaster.

I assumed you only wanted a token nod to combat, to be able to carry mail.

If you wanted to make the ships marginally combat worthy, you should probably fill, say, half of the available hardpoints with turrets.

It would at least make a single Corsair or Patrol Cruiser hesitate to attack 1000+ Dton ships...


If you really worried about combat (LBB2), throw in a slightly oversized power plant and a computer capable of running double fire. For large ships the cost is rather small. Anyone should hesitate to engage ~100 lasers capable of double fire...

 

[AnotherDilbert]

Example:
Turning a ship with a token turret into something truly terrifying is just 10% higher freight cost under LBB2 (since you already have the crew for all those turrets).
Ship with token turret:

MT-E611112-030000-20002-0        MCr 960       5 000 Dton
bearing     1     1   1                           Crew=50
batteries   1     1   1                             TL=15
                      Cargo=3973 Fuel=510 EP=50 Agility=0

Single Occupancy    LBB2 design                   3 973     1 067
                                     USP    #      Dton      Cost
Hull, Streamlined   Custom             E          5 000          
Configuration       Flattened Sphe     6                      550
Scoops              Streamlined                                  
                                                                 
Jump Drive          W                  1    1       110       210
Manoeuvre D         W                  1    1        41        84
Power Plant         W                  1    1        64       168
Fuel, #J, #weeks    J-1, 4 weeks            1       510          
                                                                 
Bridge                                      1       100        25
Computer            m/1                1    1         1         2
                                                                 
Staterooms                                 50       200        25
                                                                 
Cargo                                             3 973          
                                                                 
Mixed Turret        Full                    1         1         1
  Weapon            Missile            2    1                   1
  Weapon            Pulse              2    1                   1
  Weapon            Sand               3    1                   0
                                                                 
Nominal Cost        MCr 1 066,60         Sum:     3 973     1 067
Class Cost          MCr   117,33        Valid        ≥0        ≥0
Ship Cost           MCr   959,94                                 
                                                                 
                                                                 
Crew &               High     0        Crew          Bridge     7
Passengers            Mid     0          50       Engineers     7
                      Low     0                     Gunners     1
                 Extra SR     0      Frozen         Service     1
               # Frozen W     0           0          Flight     0
                  Marines     0                     Marines     0
                                                                 
                                                                 
Estimated Economy of Ship     Standard                                     
       Ship price     Down Payment         Mortgage       Avg Filled
       MCr 959,94      kCr 191 988        kCr 4 000              80%
                                                                 
Expenses per jump                       Revenue                  
Bank              Cr 1 919 880          High         Cr         0
Fuel              Cr   255 000          Middle       Cr         0
Life Support      Cr   100 000          Low          Cr         0
Salaries          Cr    84 000          Cargo        Cr 3 176 000
Maintenance       Cr    38 398                                   
Berthing          Cr     5 000                                   
                                                                 
Summa            kCr     2 402                      kCr     3 176
                                                                 
     Income potential per jump     kCr 774                    
  Cost per jump per Dton cargo      Cr 605

Actually armed:

MT-E611142-030000-20002-0      MCr 1 067       5 000 Dton
bearing     5     Z   5                           Crew=50
batteries   5     Z   5                             TL=15
                      Cargo=3935 Fuel=510 EP=50 Agility=0

Single Occupancy    LBB2 design                   3 935     1 186
                                     USP    #      Dton      Cost
Hull, Streamlined   Custom             E          5 000          
Configuration       Flattened Sphe     6                      550
Scoops              Streamlined                                  
                                                                 
Jump Drive          W                  1    1       110       210
Manoeuvre D         W                  1    1        41        84
Power Plant         Y                  1    1        70       184
Fuel, #J, #weeks    J-1, 4 weeks            1       510          
                                                                 
Bridge                                      1       100        25
Computer            m/4                4    1         4        30
                                                                 
Staterooms                                 50       200        25
                                                                 
Cargo                                             3 935          
                                                                 
Mixed Turret        Full                   25        25        28
  Weapon            Pulse              2    1                  13
  Weapon            Pulse              2    1                  13
  Weapon            Pulse              2    1                  13
Mixed Turret        Full                    5         5         6
  Weapon            Missile            2    1                   4
  Weapon            Pulse              2    1                   3
  Weapon            Sand               3    1                   1
                                                                 
Nominal Cost        MCr 1 186,00         Sum:     3 935     1 186
Class Cost          MCr   130,46        Valid        ≥0        ≥0
Ship Cost           MCr 1 067,40                                 
                                                                 
                                                                 
Crew &               High     0        Crew          Bridge     7
Passengers            Mid     0          50       Engineers     7
                      Low     0                     Gunners    30
                 Extra SR     0      Frozen         Service     1
               # Frozen W     0           0          Flight     0
                  Marines     0                     Marines     0
                                                                 
                                                                 
Estimated Economy of Ship     Standard                                     
       Ship price     Down Payment         Mortgage       Avg Filled
     MCr 1 067,40      kCr 213 480        kCr 4 448              80%
                                                                 
Expenses per jump                       Revenue                  
Bank              Cr 2 134 800          High         Cr         0
Fuel              Cr   255 000          Middle       Cr         0
Life Support      Cr   100 000          Low          Cr         0
Salaries          Cr    84 000          Cargo        Cr 3 148 000
Maintenance       Cr    42 696                                   
Berthing          Cr     5 000                                   
                                                                 
Summa            kCr     2 621                      kCr     3 148
                                                                 
     Income potential per jump     kCr 527                    
  Cost per jump per Dton cargo      Cr 666

 

[Grav_Moped]

The 400 Dt standard hull is very usable at J-1 and J-2. See my example in post #5. It is cheaper than the 800 Dt example you made for TL-9 and J-1.

But does it come out cheaper per payload ton in operation? That's the factor I'm trying to optimize in this exercise.

 

[Grav_Moped]

The Gazelle made it firmly canonical.

That's fine. It's also not used in canon for commercial ships (it was tried once, then stopped after a disaster).

TCS even introduced a specific type of tank for this type of application: External Demountable Tank, but since it just as expensive as Drop Tanks but not as flexible, I just use Drop Tanks.

I still have no idea what the point of External Demountable Tanks was, when Drop Tanks already existed.

Agreed, but they are unarmored transports. If someone really shoots at them, they are dead...

Sure. But I don't have to make it easy.

 

[Grav_Moped]

I assumed you only wanted a token nod to combat, to be able to carry mail.

If you wanted to make the ships marginally combat worthy, you should probably fill, say, half of the available hardpoints with turrets.

It would at least make a single Corsair or Patrol Cruiser hesitate to attack 1000+ Dton ships...


If you really worried about combat (LBB2), throw in a slightly oversized power plant and a computer capable of running double fire. For large ships the cost is rather small. Anyone should hesitate to engage ~100 lasers capable of double fire...

I'm not really worried about combat. That will be covered by a risk premium on the cargo rate (which would reflect either the cargo space reduction from carrying weapons or the cost of hiring escorts). [Insert "budget line-item for hookers and blow" joke here]

And yes, "bigger ships can have more turrets" is one of the keys to LBB2 space combat (the others are a good software suite and carried small craft).

 

[Grav_Moped]

Well, it's up to the owner whether or not he has a ship susceptible to damage. That is why I'd rule 10 jumps and replace. Soon it will be more expensive than hull.

I'm trying to work out the baseline rules-as-written ships that would set the price floor on cargo rates. That is, cargo rates will almost never be lower than what it costs to run these ships, but there are justifications for the rates being higher (risk premium, not enough ships, etc.) The actual ships used in commerce will not be this minimal, but aren't going to be rules-lawyer specials, either. I'm just assuming the rules describe typical ships.

That's why at least for now I'm using LBB2 rules as written for the LBB2 ships rather than building LBB5 ships with LBB2 drives, and not using drop tanks.

This does mean that someone who wanted to set up a network of drop tank suppliers and all that goes with it could come into a subsector and make bank... or not.

 

[AnotherDilbert]

It's also not used in canon for commercial ships (it was tried once, then stopped after a disaster).

No, it is used commercially according to canon, it was suspended by one shipping line using a dodgy supplier in one subsector:

⑆Regina (Spinward Marches 1910) Date: 186-1106
...
¶ A spokesman for Tukera Lines announced indefinite suspension of high capacity commercial service to the Regina Subsector pending outcome of the official investigation of the Trimkhana-Brilliance tragedy.
...
¶ A Tukera Lines press release stated that a team of company engineers would be "taking a long hard look at General Shipyards' quality control standards."

Sure. But I don't have to make it easy.

A single hit to the PP, M-drive, jump drive, or regular tanks is just as much of a mission kill as the drop tanks.



If you don't like drop tanks, just say you don't use them in your campaign.

 

[Proneutron]

I'm trying to work out the baseline rules-as-written ships that would set the price floor on cargo rates. That is, cargo rates will almost never be lower than what it costs to run these ships, but there are justifications for the rates being higher (risk premium, not enough ships, etc.) The actual ships used in commerce will not be this minimal, but aren't going to be rules-lawyer specials, either. I'm just assuming the rules describe typical ships.

That's why at least for now I'm using LBB2 rules as written for the LBB2 ships rather than building LBB5 ships with LBB2 drives, and not using drop tanks.

This does mean that someone who wanted to set up a network of drop tank suppliers and all that goes with it could come into a subsector and make bank... or not.

Good idea to see what the floor rates could be. Better to understand what type should be plying what lines...

 

[mike wightman]

That's fine. It's also not used in canon for commercial ships (it was tried once, then stopped after a disaster).I still have no idea what the point of External Demountable Tanks was, when Drop Tanks already existed.Sure. But I don't have to make it easy.

Not quite.
The Traveller News article states that use of drop tanks on civilian ships is routine in the core worlds of the Imperium, and has been for some time.
The 'disaster' occurred when they tried to use the technology in the Spinward Marches.

Spoiler:

Conjecture on my part is that this was no accident. Either local shipping concerns such as Oberlindes Lines or local freedom fighters such as the Ine Givar wanted to make sure the Imperium didn't become even more dominant in the Marches.

 

[Grav_Moped]

Now for the Jump-2 LBB2 ships:

                            Tons                     Cost/Jump per
TL     Tons     Drives     Payload      Cost/Jump     Ton Payload    Notes:
 9     400        D          208        J1: 266818       1283        (Std hull wastes 9Td) 
                                        J2: 291818       1403

10     800        H          497        J1: 615527       1239
                                        J2: 660527       1329
        
11-14 1000        K          639        J1: 759200       1188
                                        J2: 814200       1274

15    5000        Z         3439        J1:2820967       820
                                        J2:3075967       894

Lowest cost per parsec:

                Using ship            Using ship
                  of __                 of ___
TL   Cr/T(1Pc)  Tons, as:  Cr/T (2Pc) Tons, as:
9       649      600, 1J1     1298     600, 2J1
10      649      600, 1J1     1298     600, 1J1
11      649      600, 1J1     1274    1000, 1J2
12      649      600, 1J1     1274    1000, 1J2
13      649      600, 1J1     1274    1000, 1J2
14      649      600, 1J1     1274    1000, 1J2
15      649      600, 1J1      894    5000, 1J2

Observations:
For this set, the only one for which a standard hull makes sense is the TL-9 J-2 400Td ship (and none of the J-1 ships). Weirdly, the 800 and 1000Td standard hulls only save build time, not money.

Mistaken observation spoilered but retained for the record

Spoiler:

For any TL, J-2 is only slightly cheaper to 2 parsecs than 2xJ-1.

Revised observation: 2J1 is significantly cheaper at TL-9 and 10. Then 1J2 is cheaper until...

EXCEPT for the 5000Td TL-15 JD-Z ship. That one is a LOT more cost-effective than the TL-15 JD-W ship jumping twice. It's the Magic of Z!

So, at least so far (J-1 and J-2), it looks like cargo rates should be on a per-parsec rather than a per-jump basis. Until the Z Drive comes into play...

We'll see how that looks at higher jump numbers.

 

[Grav_Moped]

Not quite.
The Traveller News article states that use of drop tanks on civilian ships is routine in the core worlds of the Imperium, and has been for some time.
The 'disaster' occurred when they tried to use the technology in the Spinward Marches.

Spoiler:

Conjecture on my part is that this was no accident. Either local shipping concerns such as Oberlindes Lines or local freedom fighters such as the Ine Givar wanted to make sure the Imperium didn't become even more dominant in the Marches.

Fair point.

And your conjecture seems plausible.

 

[Grav_Moped]

No, it is used commercially according to canon, it was suspended by one shipping line using a dodgy supplier in one subsector:





A single hit to the PP, M-drive, jump drive, or regular tanks is just as much of a mission kill as the drop tanks.



If you don't like drop tanks, just say you don't use them in your campaign.

Drive hits can be repaired. Fuel hits can't. Fuel hits that wipe out the entire Jump fuel allocation are a mission kill.

LBB2 leaves a little resilience on fuel hits: they're 10Td rather than "10% but minimum 10Td". Still knocks the ship below the threshold for jump on J1 ships. For J2 and up, it makes a difference -- LBB5, each fuel hit takes out J1 fuel; LBB2, the first hit takes out J1 fuel but it takes several hits to take out the second J1 fuel, especially for larger ships.

I don't like drop tanks for commercial use in general. I see the military designing ships to take advantage of them, but civilians probably wouldn't. I don't see them as reliable enough to be a core component of a ship that's supposed to generate revenue for 40 years. As an accessory for occasional use, as in rift-jumping to access a profitable cluster, trace, or main -- sure. As something dropped every Jump, or carried as a permanent cheap-and-fragile fuel tank -- no.

At least for this exercise I am just trying to model the sort of ships that the original trade rules were written around. Basically, trying to figure out what cargo rates would have been if the game designers had written a "spreadsheets in space" trade system rather than one mostly meant to encourage players toward speculation rather than cargo-hauling.

 

[mike wightman]

There are rules in the K'kree module for what happens if you use LBB5 designed ships in LBB2 combat:

When K'kree ships constructed using this system are involved in space combat from basic Traveller, each hit on a drive reduces the drive number by 0.2 (one-fifth of a point). Drives function at their current number, rounding fractions down; this system is similar to the reduction of alphabetic drive letters by one letter for each hit.

 

[AnotherDilbert]

Drive hits can be repaired. Fuel hits can't. Fuel hits that wipe out the entire Jump fuel allocation are a mission kill.

LBB2 leaves a little resilience on fuel hits: they're 10Td rather than "10% but minimum 10Td". Still knocks the ship below the threshold for jump on J1 ships. For J2 and up, it makes a difference -- LBB5, each fuel hit takes out J1 fuel; LBB2, the first hit takes out J1 fuel but it takes several hits to take out the second J1 fuel, especially for larger ships.

LBB5 fuel hits are 1%, at least 10 Dt, so for small ships it's the same 10 Dt fuel lost as a LBB2 fuel hit.

As you note, for a J-1 ship, as we had discussed so far, the effect of a single fuel hit leaves the ship unable to jump, or if incoming after jump totally without fuel, whether using a drop tank or not.

Fuel hits has to repaired, same as any other hit, before the system can be reliably used again. If we go by TCS any hit takes a few weeks in the yard to repair.

For a J-1 ship any drive hit basically leaves you drifting helplessly, and even after temporary repairs needs weeks in the yard for permanent repairs. I certainly consider that a mission kill for a weeks cargo run.

I don't like drop tanks for commercial use in general. I see the military designing ships to take advantage of them, but civilians probably wouldn't.

Interesting, I see the opposite. Using drop tanks would be a monumental logistical nightmare for the navy, but transports could easily use them. If they are not reliable enough for civilians, they are presumably not even remotely reliable enough to be used in the field by combat craft.

Routinely dropping the tanks can only easily be done when jumping to systems with good shipyards where new pre-purchased tanks are waiting, so only on specific scheduled routes.

The Scouts seems to think they are reliable enough for routine use:

⑆ Regina (Spinward Marches 1910) Date: 101-1105
By TNS Staff Writer
¶ Close on the heels of the joint announcement by General Shipyards and Tukera Lines that L-Hyd drop tanks would soon be manufactured in the Regina Subsector, came word by express boat from the Imperial core that a decision has been made to deploy Jump-6 L-Hyd drop tank express boats on all major express routes. ...

 

[Proneutron]

As you note, for a J-1 ship, as we had discussed so far, the effect of a single fuel hit leaves the ship unable to jump, or if incoming after jump totally without fuel, whether using a drop tank or not.

Under B2 rules PP fuel is separate from J fuel. "Power plant fuel under the formula (10Pn) allows routine operations and maneuver for four weeks. Jump fuel under the formula (0.1 MJn) allows one jump ..."

 

[whartung]

Somewhere there's a table to compensate for costs based on tech level. Something akin to "what costs XXX at TL 11, cost YY% less at TL 15".

So, don't forget to take those discounts in to consideration in your analysis.

 

[coliver988]

Somewhere there's a table to compensate for costs based on tech level. Something akin to "what costs XXX at TL 11, cost YY% less at TL 15".

So, don't forget to take those discounts in to consideration in your analysis.

Striker Book 2 p39 has a cost adjustment table based on starport & tech level.

First time I've opened those books in years - spent way too much time in college designing vehicles when I should have been studying

 

[Grav_Moped]

LBB5 fuel hits are 1%, at least 10 Dt, so for small ships it's the same 10 Dt fuel lost as a LBB2 fuel hit.

I mis-read that -- my bad.

As you note, for a J-1 ship, as we had discussed so far, the effect of a single fuel hit leaves the ship unable to jump, or if incoming after jump totally without fuel, whether using a drop tank or not.

LBB2 ships with Pn3+ leave jumpspace with at least 15T fuel.

Fuel hits has to repaired, same as any other hit, before the system can be reliably used again. If we go by TCS any hit takes a few weeks in the yard to repair.

I was thinking in the context of combat only. You can patch the tanks, but until you get to a starport they're still empty.

For a J-1 ship any drive hit basically leaves you drifting helplessly, and even after temporary repairs needs weeks in the yard for permanent repairs. I certainly consider that a mission kill for a weeks cargo run.

Again, the context is combat. If it can be battle-damage-repaired, you're back in the game.

Interesting, I see the opposite. Using drop tanks would be a monumental logistical nightmare for the navy, but transports could easily use them. If they are not reliable enough for civilians, they are presumably not even remotely reliable enough to be used in the field by combat craft.

The military is prepared to take higher risks than civilians in order to achieve objectives. Also, while their ships have the same service lives as civilian ones, they expect attrition in battle so the actual service life of a military ship is probably somewhat shorter.

Routinely dropping the tanks can only easily be done when jumping to systems with good shipyards where new pre-purchased tanks are waiting, so only on specific scheduled routes.

That's part of my point. I'm modeling generic shipping on the frontier, not the Imperial core sectors. Or at least generic shipping as described in LBB2 and to some extent in LBB7.

The Scouts seems to think they are reliable enough for routine use:

...and then, nothing. Plans might have been interrupted for reasons other than technical flaws, but I don't think the writers followed up on it. (Well, other than the secret J-6 couriers disguised as J-2 freighters, but I don't think they used drop tanks.)