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

[Grav_Moped]

Re: 10Td/Pn fuel requirement:

It's not that it's a problem for very small ships, it's that it's broken, rooted an unrealistic (or perhaps more accurately, implausible) first edition fuel consumption rule that was entirely abandoned in both editions of High Guard and its basis never used for design rules after LBB2'81. The thing is, though, that fuel use couldn't just be fixed in isolation because it was the constraint on maneuver drive capability (though in LBB2'81, it was only really constraining Gs above Jn). If fuel use was set to HG rates, building 6G ships would be easy with LBB2 maneuver drives (though perhaps expensive). And it'd break or seriously distort larger LBB2 ships. The fix adopted for HG was simply to make maneuver drives larger -- but applying that to LBB2 would break all previously-published designs from that system.

And that's why I dislike the notion of intermixing LBB2 and LBB5 drives. Each system has its own set of forced tradeoffs, that worked within the purposes of that system. A "mix-and-match" approach bypasses those balances, leading to results that neither system intended to be allowed.

 

[AnotherDilbert]

Traveller 5 modifies that with TL Stage Effects, but that's the rate at standard TL -- unless I'm misreading something and starship power plants are "centralized" in which case the standard rate is 2%/Pn (and how does a "decentralized" starship power plant even work?)

Centralised: The power plant powers all the equipment in the ship, like CT.
Decentralised: The power plant only powers the drives, most other equipment powers itself by the magic of Fusion Plus, at no cost in space, money, or fuel.

For some reason most T5 ships seems to choose Decentralised power...

 

[AnotherDilbert]

And that's why I dislike the notion of intermixing LBB2 and LBB5 drives. Each system has its own set of forced tradeoffs, that worked within the purposes of that system. A "mix-and-match" approach bypasses those balances, leading to results that neither system intended to be allowed.

Agreed, but that is what LBB5'80 explicitly says...
LBB2 is no stranger to LBB5, since the LBB2 standard small craft are built by the LBB5 system.

At least we can't use cheap LBB2 standard hulls with smaller LBB5 drives by the book.

 

[Grav_Moped]

Agreed, but that is what LBB5'80 explicitly says...
LBB2 is no stranger to LBB5, since the LBB2 standard small craft are built by the LBB5 system.

'77 didn't have a system for small craft. Neither did '81 for that matter; they used LBB5'80 without explanation.

At least we can't use cheap LBB2 standard hulls with smaller LBB5 drives by the book.

That's what hull configurations 4-7 are for.

 

[Murph]

For book2 use M*Pn*0.01 instead of Pn*10.

As per Both editions of Book5.

I will take a look at that. It could be interesting.

 

[Murph]

Also if you build a Free Trader on a Tech level 14 world, would it not be a tech level 14 free trader rather than the TL 10/11/12 ones in the books? Same goes with TL 15 worlds, you build at the tech level. Look at modern Aircraft mfg, and automobile mfg for an example of this. Who in this day and age can build a 1940's car as a non one off vehicle? As tech advances, you lose the ability to make lower tech items through loss of machinery, tooling, and just plain old knowledge base.

 

[infojunky]

Also if you build a Free Trader on a Tech level 14 world, would it not be a tech level 14 free trader rather than the TL 10/11/12 ones in the books?

Well that depends, What is the source of the drives? Meaning ships are an assembly of parts which are sourced to the lowest bidder. Couple that to the Concept of Standard Drives, which are probably sourced to systems who can produce the drive to the required spec.

Now, then using none standard drives, then Local-ish Tech Level matters more

Same goes with TL 15 worlds, you build at the tech level. Look at modern Aircraft mfg, and automobile mfg for an example of this. Who in this day and age can build a 1940's car as a non one off vehicle? As tech advances, you lose the ability to make lower tech items through loss of machinery, tooling, and just plain old knowledge base.

The more apt question is who builds 1940s style aircraft and boats I know of several shops and small boat yards that do just that.

 

[Murph]

Well that depends, What is the source of the drives? Meaning ships are an assembly of parts which are sourced to the lowest bidder. Couple that to the Concept of Standard Drives, which are probably sourced to systems who can produce the drive to the required spec.

Now, then using none standard drives, then Local-ish Tech Level matters more

The more apt question is who builds 1940s style aircraft and boats I know of several shops and small boat yards that do just that.

True, small shops which are essentially custom master craftsmen who keep the old skills alive.

 

[AnotherDilbert]

Also if you build a Free Trader on a Tech level 14 world, would it not be a tech level 14 free trader rather than the TL 10/11/12 ones in the books?

LBB2 ships don't really have a tech level. All class A starports (even Kinorb TL8) can build any LBB2 ship, regardless of tech level, presumably using standardised components.

 

[Grav_Moped]

Also if you build a Free Trader on a Tech level 14 world, would it not be a tech level 14 free trader rather than the TL 10/11/12 ones in the books? Same goes with TL 15 worlds, you build at the tech level. Look at modern Aircraft mfg, and automobile mfg for an example of this. Who in this day and age can build a 1940's car as a non one off vehicle? As tech advances, you lose the ability to make lower tech items through loss of machinery, tooling, and just plain old knowledge base.

Build? Probably not that many, but look to light aircraft for a counterexample. The Cessna 172 has been around in almost continuous production since 1956, and you can likely still get the early Continental engines (used through 1967, superseded by Lycomings) overhauled.

LBB2 ships don't really have a tech level. All class A starports (even Kinorb TL8) can build any LBB2 ship, regardless of tech level, presumably using standardised components.

They do at construction time, but not for ongoing maintenance.

 

[AnotherDilbert]

They do at construction time, but not for ongoing maintenance.

LBB2 says:

- - Space ships are constructed and sold at shipyards throughout the galaxy. Any class A starport has a shipyard which can build any kind of ship, including a starship with jump drives; any class B starport can build a small craft and ships which do not have jump drives.

On the other hand LBB5 says:

- - Availability: Starships (with jump drives) may be constructed at the shipyard of any class A starport; non-starships (without jump drives) may be constructed at the shipyard of any class A or class B starport.
- - Technological Level: Technological level is important in the design of a ship because it governs where the ship may be produced, and how well the crew can operate and maintain it. The technological level of the building shipyard determines the technological level of the ship being constructed (a class A starport on a tech level 14 world constructs a tech level 14 ship). Equipment and components of a starship may always be equal to or less than the ship's tech level.

Only LBB5 ships are limited by the starports TL. Some LBB2 components may have a TL, but that does not limit where the ship is assembled.

 

[mike wightman]

Annual maintenance for a LBB2 ship may be performed at any A or B starport regardless of world TL.

3. Routine Maintenance. Annually, a starship should be given a complete overhaul
in order to insure that it is kept in good working order. Such maintenance
costs 0.1% (1/1000th) of the cash price of the ship, and requires two weeks at a
class A or B starport.

Then there are all those TL 15 Imperial Navy bases on worlds that have lower TL, I would imagine any IN base can provide the annual check for TL15 IN ships regardless of world TL.

 

[kilemall]

Annual maintenance for a LBB2 ship may be performed at any A or B starport regardless of world TL.

Then there are all those TL 15 Imperial Navy bases on worlds that have lower TL, I would imagine any IN base can provide the annual check for TL15 IN ships regardless of world TL.

If we are going into maintenance and build CT era, cannot neglect TCS rules.

 

[Grav_Moped]

Only LBB5 ships are limited by the starports TL. Some LBB2 components may have a TL, but that does not limit where the ship is assembled.

That is, assuming a supply chain for those components in the construction phase. Not impossible, but also seemingly not envisioned in the early Traveller canon. Expect reasonable availability of wear components (annual overhauls) and fragile components (battle damage) for higher TL drives, but not a stockpile of those drives in a ready-to-install state.

Annual maintenance for a LBB2 ship may be performed at any A or B starport regardless of world TL.

Then there are all those TL 15 Imperial Navy bases on worlds that have lower TL, I would imagine any IN base can provide the annual check for TL15 IN ships regardless of world TL.

Agreed on Naval Base support for TL-15 components for IN ships, but not for others. Maybe IISS, but most of their stuff isn't (LBB2 rules) in the size range that'd make it necessary.

 

[aramis]

And that's why I dislike the notion of intermixing LBB2 and LBB5 drives. Each system has its own set of forced tradeoffs, that worked within the purposes of that system. A "mix-and-match" approach bypasses those balances, leading to results that neither system intended to be allowed.

For a period of several years, I was using 200 PowerFactors per letter step, Bk2 sizes, PP fuel = 1 Td/week/letterstep, and JFuelTd = 5×JDTd in some worldbuilding exercises (that came to nought)
Rating of drive was PF/HullTd, Round PP & MD down to nearest 0.1, and JD down to nearest integer, but a raw rating of >0.5 being a "J0" drive with 1 light-year range.

I'm inclined to use that next time I run, but I think I'll use an uneven.
Oh, and I call 100Td Bays "Spinals"...

 

[Grav_Moped]

PP fuel = 1 Td/week/letterstep

Hmmn... interesting angle on that.

 

[aramis]

If LBB2 can't handle straight percentages, I suspect calculating the cube root of the volume, squared, is a bit over the top...

It can, provided you set a minimum size, and don't mind some rounding... and don't mind not matching drives abovea

System	Td Rate	MCr Rate	Td per Hit
PP	Pn × 1.5% +1Td	HTd × 4%	3
MD	Gn × 1.0% -1 Td min 1 Td	HTd × 2%	2
JD	Jn × 2.5% +5 Td	HTd × 5%	5

Bk2-77 matches 200 rating per letter to drive R and then squirrels out.
Bk2-81 squirrels out at N...

 

[aramis]

Hmmn... interesting angle on that.

Stolen from Gareth Hanrahan...

 

[Grav_Moped]

For a period of several years, I was using 200 PowerFactors per letter step, Bk2 sizes, PP fuel = 1 Td/week/letterstep, and JFuelTd = 5×JDTd in some worldbuilding exercises (that came to nought)
Rating of drive was PF/HullTd, Round PP & MD down to nearest 0.1, and JD down to nearest integer, but a raw rating of >0.5 being a "J0" drive with 1 light-year range.

Hmmn... interesting angle on that.

So, 4% per EP per month for the power plant, in (apparently) 1 week minimum increments. Not too far off from average fuel use per Pn across the LBB2 hull size range. It's a bit late at night for me to try to do the actual math on that though... LOL

I've always taken the 10%/Jn as the one thing that never changes.

 

[aramis]

So, 4% per EP per month for the power plant, in (apparently) 1 week minimum increments. Not too far off from average fuel use per Pn across the LBB2 hull size range. It's a bit late at night for me to try to do the actual math on that though... LOL

I've always taken the 10%/Jn as the one thing that never changes.

MT introduced the 5×JDTd ... and I generally prefer MT. Altho' Alien's scratched the same itch...