LBB2 M-Drives in LBB5: When does it help?

[Condottiere]

Assuming the technological level is the same, or close enough, starports would have three dee printers to make one off spare parts.

I would think the question would be cost and time, in relation to some factory mass producing the components.

In terms of artisanship, I used to hear stories of cars breaking down in the middle of nowhere, and the local mechanic reproducing the broken part, until electronics got in the way.

 

[mike wightman]

They are now called makers...

I am lead to believe that US carriers now have extensive 3d printing etc to manufacture replacement parts for their aircraft...

 

[aramis]

Assuming the technological level is the same, or close enough, starports would have three dee printers to make one off spare parts.

I would think the question would be cost and time, in relation to some factory mass producing the components.

In terms of artisanship, I used to hear stories of cars breaking down in the middle of nowhere, and the local mechanic reproducing the broken part, until electronics got in the way.

given that CNC mills can be used to carve single or dual (front/back) layer circuit boards...
Likewise, there are half a dozen microfabbers doing custom IC's at the 15 µm range (peak tech currently is 5nm - a full house of magnitude finer)... The 6502 is about 8.3 µm resolution. I can't fnd the lithography resolution for the Z80, but recall it being a bit finer - ISTR 5 µm.

There are even home shop guys doing low resolution lithography for one-off chips. One "garage lithography" IC creator has most features in the 125µm range, but some as fine as 2µm are on said chip.¹

If you can do 2µm features on a garage pmos lithography system, 5v 8bit cpu and memory is doable. Hell, NASA still uses Z80's... in a slightly reduced version - finer lithography, slightly smaller die, but still a 5v cpu, and I seem to recall a 3.3v z80 clone. And 1µm lithos are now relatively cheap. The only truly expensive part for 1µm chips manufacture is the silicon itself. The masks are optically reduced; high quality laser printers can produce them. Several makers note that they set up hobbyist 25µm optical foundries for about US$15,000.00 suitable for certain low-density 5v and 12v utility chips. The better end is able to replicate simpler 8 bit chips - both CPUs and support chips.

So even the ICs on the 70's stuff is remakable... I have this quirky dream of a 16bit registers & data bus (and memory word), 32 bit address bus, using the 6502 instruction set... and a 16bit memory word... at about 3v and 100-200 MHz...

1: http://sam.zeloof.xyz/first-ic/

 

[Murph]

And I cannot disagree, but in some ways Alaska is a very specific case since your needs up there are different than in Texas for example. But I suspect that if you asked Pratt and Whitney to build an old style engine it would take them some time to make the tooling, and blueprints to make it happen. I have no doubt they could, but it would take time, since they have moved on to more "modern" items. One of my favorite a/c the C-123, I doubt you could find anyone who could make new ones production line style. But your point is well taken, and certainly can be applied to Traveller easily.

 

[Condottiere]

Transport costs, not to mention time lag, would factor in.

In Traveller terms, I don't think replicating electronics presents an unsurmountable hurdle, but I would think that there are jump drive components that would be more difficult to duplicate, or there is no warranty, and you jump without a net (coverage).

 

[aramis]

And I cannot disagree, but in some ways Alaska is a very specific case since your needs up there are different than in Texas for example.

See Alaska: an American Colony by Steven Haycox, PhD, for why it's perfect case for pop 5 worlds... a title Steve got from a conversation he and I had when I was in my undergrad.
within the ConUS, nothing functions economically autonomously since about 1940.
Within Europe, nothing functions economically autonomously since the renaissance, and arguably, since the dark ages or before.
They're both too interdependent to look at what is needed for a function.
Alaska, Hawaii, New Zealand, the FSM, Samoa, Tonga, the VI, the USVI, even Cuba and Haiti are all good case points for looking at how low-mid pop worlds should be able to support their own infrastructures.
None are perfect... but they're better than anywhere on any of the mainlands of each continent.

 

[aramis]

Assuming the technological level is the same, or close enough, starports would have three dee printers to make one off spare parts.

I would think the question would be cost and time, in relation to some factory mass producing the components.

In terms of artisanship, I used to hear stories of cars breaking down in the middle of nowhere, and the local mechanic reproducing the broken part, until electronics got in the way.

It won't be all printers. It will be a mix of additive (printers) and subtractive (CNC routers), as well as joining (CNC welders).

Hell, I'd expect a couple machine shops near any port, even an E-port. At least if it's TL5+

 

[Murph]

See Alaska: an American Colony by Steven Haycox, PhD, for why it's perfect case for pop 5 worlds... a title Steve got from a conversation he and I had when I was in my undergrad.
within the ConUS, nothing functions economically autonomously since about 1940.
Within Europe, nothing functions economically autonomously since the renaissance, and arguably, since the dark ages or before.
They're both too interdependent to look at what is needed for a function.
Alaska, Hawaii, New Zealand, the FSM, Samoa, Tonga, the VI, the USVI, even Cuba and Haiti are all good case points for looking at how low-mid pop worlds should be able to support their own infrastructures.
None are perfect... but they're better than anywhere on any of the mainlands of each continent.

That is a really good analogy.

 

[Condottiere]

Starport Epsilon could be the equivalent of having a pier to dock, and the harbourmaster's office for registration and fee payment.

The machine shops, and all the usual amenities could be in the startown, which could indicate a mobile garage, or the need to relocate the spacecraft in the outskirts for repairs.

 

[Grav_Moped]

Long reachback:

I'm not sure that fixed ship sizes are necessarily a bad thing. This is a game, not a simulation. And complexity is sort of T5's raison d'etre...

Why would a 200 Dt ship be preferable to a 150 Dt of 300 Dt ship? Why should the system try to force me into a 200 Dt ship?

Because the drives are available in standard sizes, each with a fixed "effect * tons" value.

I personally don't think they need to be restricted to those standard sizes, as long as the underlying formulae used to create the Drive Performance Table in LBB2 are adhered to.* But canon says those are the drives that are available, and gives their outputs, and it's those that dictate optimal hull sizes.

-----------
* With two caveats: don't extrapolate beyond where the formulae make sense (M-Drives below Size A), and use multi-point interpolation for regions of known deviance from the forumlae (W-Z Drives). Intermediate "custom-sized" drives will present supply-chain issues. Unlike Letter-Size Drives, custom-sized drives will need spares/overhaul components to be produced locally, or imported if the local TL and industrial base are inadequate for local production.

 

[mike wightman]

What if:
there is a different formula for small craft drives (the type A drive does appear to be used as does an A/2)
the advantage of the W-Z drives are deliberate, and there is a different formula for them?
the overall formula is more complex than a simple linear relationship?

Time to graph them in Excel again - I know I did this by hand several decades ago but why not let Excel give me the formula at the push of a button?

 

[Grav_Moped]

What if:
there is a different formula for small craft drives (the type A drive does appear to be used as does an A/2)

There is one: they simply took it from LBB5, that's all.

My twist on this is to reach back to '77 (where the PP was just for the M-Drive) and combine the PP and M-Drive into a single component called "Small Craft Drives". The (%+1Td) for the power plant cancels the (%-1Td) of the maneuver drive, making the size formula a straight percentage. Cost for all LBB2 drives is linear by (rating*tonnage), so that scales down evenly as well. Perhaps have a 1Td minimum (maybe 2Td?), with the cost being for the capability, not the size of the drive. I did the math on this once a while back, but it's late and I'm too tired to look up where I posted it... sorry.

The other two tricks to this are that a "small craft drive" doesn't produce excess energy points; you need a separate (%+1Td) power plant for weapons and computers that use EPs, and you don't need all of the 10Td/Pn fuel (don't quite remember what number I used for that).

the advantage of the W-Z drives are deliberate, and there is a different formula for them?

It is deliberate -- and it's inconsistent. The only way to get an "accurate" result for intermedate-sized drives in that zone of the tables is by weighted interpolation from the surrounding data points.

the overall formula is more complex than a simple linear relationship?

Well, yeah. It needs to account for the interpolation issues at the top end -- which are not easily amenable to even a complex formula, as the performance upgrades appear to have been applied arbitrarily.

 

[AnotherDilbert]

Why would a 200 Dt ship be preferable to a 150 Dt of 300 Dt ship? Why should the system try to force me into a 200 Dt ship?

Because the drives are available in standard sizes, each with a fixed "effect * tons" value.

But there are no abstract "potential-tons" in LBB2, there is only a table that forces some random hull sizes to be even remotely efficient.

A drive J in a 600 Dt hull is potential 3, so in a 300 Dt hull it's of course potential 6? No, it's potential 4 because the table isn't granular enough... Hence 300 Dt hulls are strongly discouraged for no good reason.

Why is my ship penalised just because I wanted to make it 300 Dt?


Essentially, this is much simpler (and works for any size from 5 Dt to megatons):



than this, that only works for a few specified hull sizes:


LBB2 might be better than nothing, but it's not very good...

 

[AnotherDilbert]

What if:
there is a different formula for small craft drives (the type A drive does appear to be used as does an A/2)

Mongoose 1e has lettered drives for small craft:




But do you really want all of that to be able to build something as simple as a smallcraft?

 

[mike wightman]

This is a copy of something I did from years ago:

Drive

A

B

C

D

E

F

G

H

J

K

L

M

N

P

Q

R

S

T

U

V

W

X

Y

Z

Output

200

400

600

800

1100

1200

1400

1600

?

2000

2300

2400

2600

2800

3000

3200

3400

3600

3800

4000

?

?

?

?

Output/hull tonnage = performance number (round down)
Broken for J drives (should the 400t J drive have performance 5?), the W-Z drives are way overpowered for some of the hulls they are rated for (the 800t could be removed for W-Z, and 1000t removed for Y-Z thus allowing for W=5000, X=6000, Y=8000, Z=12000).
Could the J and the W-Z drives be variable output?

 

[infojunky]

I personally don't think they need to be restricted to those standard sizes, as long as the underlying formulae used to create the Drive Performance Table in LBB2 are adhered to.* But canon says those are the drives that are available, and gives their outputs, and it's those that dictate optimal hull sizes.

A pont here, on the standard drives, their size per performance is largely irrelevant, in that the fuel load to operate said drive largely is dependent on the hull size rather than the drive size. I don't have a problem with the mechanic of intermediary hull sizes.

As for small craft they generally use either a A class Power and drive. Note I have postulated subA and subB sized drives to allow for a wider range of small craft as well as a J1 100 ton hull.

Though I prefer using the 200 to 4800 performance range for standard drives as it largely covers what we Know as the Adventure Size Class of ships.

Side-note, I have pondered using Book5 to generate the standard drives as match the relative preportion sizes between the two sources.

 

[AnotherDilbert]

Broken for J drives (should the 400t J drive have performance 5?), the W-Z drives are way overpowered for some of the hulls they are rated for (the 800t could be removed for W-Z, and 1000t removed for Y-Z thus allowing for W=5000, X=6000, Y=8000, Z=12000).

If you want to use a formula instead of the table, you have to ignore the idiosyncrasies of the table.
No, the J drive isn't a K drive sometimes, it shouldn't have a rating for a 2000 Dt hull.
Overpowered isn't really a problem? Just cap drive potential at 6 and let people use as large drives as they want?

Could the J and the W-Z drives be variable output?

Presumably no, the table is just a bit irregular.

 

[Spinward Flow]

Could the J and the W-Z drives be variable output?

The problem is the table structure ... and using one of these to make things fit within it ...

 

[kilemall]

The point of too large drives would be damage capacity, or tug work.

 

[Grav_Moped]

This is a copy of something I did from years ago:

Drive

A

B

C

D

E

F

G

H

J

K

L

M

N

P

Q

R

S

T

U

V

W

X

Y

Z

Output

200

400

600

800

1100

1200

1400

1600

?

2000

2300

2400

2600

2800

3000

3200

3400

3600

3800

4000

?

?

?

?

Output/hull tonnage = performance number (round down)
Broken for J drives (should the 400t J drive have performance 5?), the W-Z drives are way overpowered for some of the hulls they are rated for (the 800t could be removed for W-Z, and 1000t removed for Y-Z thus allowing for W=5000, X=6000, Y=8000, Z=12000).
Could the J and the W-Z drives be variable output?

Size J Drives at 2000Td are a deviation from the formula; the rating should be 0.9, but it was rounded up to 1. ("Performance number" of 1800.)
At 400Td, they would have a rating of 4.5 (which was then, as per most of the rest of the table, rounded down).

The W-Z drives just had higher values stuffed into the table to enable the largest hulls to have decent performance without needing drives beyond Z (as @Spinward Flow pointed out, above). This doesn't appear to have been distributed entirely evenly, which is why manual multi-point interpolation is necessary.