Work with me here...

[miketr]

1880 - 1939 is a wide range in there.

With chemistry at 1980's level lots of things are possible its all just a question of cost really.  Electromechanical computer is a big deal.  Both of these require precision processes in terms of machining knowledge.  Fire control would start at 1945 level of accuracy. 

Almost sounds like a steam punk setting. 

One thing to keep in mind.  All of the military knowledge is book learned.  Its taken out of a manually but the practical experience in application; especially on the small unit level is lacking.  Its like given person off the street infantry officers hand book and some books on tactics; it doesn't mean they are good combat leader.  It would be like the start of the ACW lots of volunteers, lots of enthusiasm but very little practical experience even the generals in charge of 10's of thousands of men were typically used to commanding at best battalions and mostly companies.

So not sure how you have a tech tree under this setup is all.  It would be more of an experience growth than anything.   Re-discovering the fine details as to what does and doesn't work.

Michael

[Carthaginian]

Mike, look down the page at the examples listed for each tech level- that was more what I was going by.

TL6    Automobiles; continental railways; ocean liners; submarines; aircraft.    
Smokeless powder; automatic weapons; tanks; combat aircraft.    
Steam turbines; internal combustion; alternating current; hydroelectricity.    
Antibiotics; blood typing and safe transfusions; heredity; biochemistry.

TL7    Nuclear submarines; jet aircraft; helicopters; manned space flight.    
Ballistic body armor; guided munitions; combat jets; nuclear weapons.
Gas turbines; fission; solar power.    
Discovery of DNA; organ transplants; pacemakers.

When you look at these examples, then it makes a bit more sense than looking at the dates given.
Computers that are late TL6/Early TL7 would be the primitive electronic computers of the Apollo program (computers that can fit into a single room), the stuff on ships would be more like the Torpedo Data Computers on American submarines. Some factories would have modern desktops/servers for managing production, but these computers would be in very short supply and impossible to reproduce (at startup). Each nation-state would have one central computer that is 'handwaviumed' to allow it to contain all the accumulated knowledge of mankind, for research purposes.

[Valles]

I think that it might go better if the 'data cores' were either lost, or not yet readable - if the research going on wasn't so much just looking things up then working out how to carry them out, as reconstructing techniques from vague, fragmentary references in works that might well not have anything to do with their actual application.

Like trying to figure out how to build a battleship by collecting books about WWI.

It seems to me like this approach would strain the suspension of disbelief less - less chance of one major breakthrough by one power leading to a runaway success.

[Carthaginian]

I think that it might go better if the 'data cores' were either lost, or not yet readable - if the research going on wasn't so much just looking things up then working out how to carry them out, as reconstructing techniques from vague, fragmentary references in works that might well not have anything to do with their actual application.

As I said in the other thread computers can only develop as fast as the rest of your tech.
I might be able to read about designing an interstellar spacecraft with a fusion core, but until I have built the things I need to build the things I need to build the ship... well I really can't do shit with that knowledge.

[The Rock Doctor]

Jamie's broadly on target with the GURPS comparison.

The nations are at TL7/8 (or early/mid 21st century) in terms of the critical areas necessary for enclosed cities and vertical farming:  Construction, hydroponics, fish-farming, mining, life-support systems, renewable power.  These were the essentials; this is what the first colonists specialized in.

In other areas, TL6 applies.  These are skills where high-tech was either not necessary (basic ship building) or they weren't needed at all but are now being reverse-engineered due to the new political situation.  Most military techs apply in the latter category - the colonists didn't have the skills when they came, didn't have the luxury of learning them until recently, and now, don't have the luxury of not learning them afresh.

Computers may vary.  They may have "modern" tech to run their cities and such, but no experience in writing software for gunnery programs or in wiring up a warship's C3I network.

Side-observation:  There are probably no technological "barbarians" on this world; they would not have survived its environment.  Imperialism here will be more like Maine annexing Kansas than Belgium annexing the Congo.

[The Rock Doctor]

Good point on Haber, Mike, that didn't occur to me.  Oil's a valid thought - my question there would be if the scale of facilities existed to support military operations.  Something to consider...

[Carthaginian]

Good point on Haber, Mike, that didn't occur to me.  Oil's a valid thought - my question there would be if the scale of facilities existed to support military operations.  Something to consider...

I'm something along Mike's line here... IF humanity could travel the stars, then we could probably have some custom-tailored microbes that are designed to produce biodiesel. As they would require very little in the way of storage space (being microscopic and all ;)), our NewWorlders would be able bring a supply along with them to help build their civilization.

Biodiesel should be pretty easily accessible- whether or not in the quantities needed to supply a large naval force, though, might be up for debate.

[miketr]

I am seeing different visions in terms of what these people have.

If they have a functional tech base but just not used to making military hardware they will quickly jump up that tree.  Nuclear Weapons, Chemical, no screwing around with chlorine they jump straight to Nerve and Blood agents.  Missiles, etc.

The cycle time will be impressive and messy.

So again if its like Sea's of Venus then airplanes are a non factor not because they can't build a jet fighter its because a jet fighter is just a flying target with the type of radar / fire control they can generate.  Or is it that they have lost something after getting to this new world and they are in a neo-barbarian stage?

Michael 

[The Rock Doctor]

Good point on Haber, Mike, that didn't occur to me.  Oil's a valid thought - my question there would be if the scale of facilities existed to support military operations.  Something to consider...

I'm something along Mike's line here... IF humanity could travel the stars, then we could probably have some custom-tailored microbes that are designed to produce biodiesel. As they would require very little in the way of storage space (being microscopic and all ;)), our NewWorlders would be able bring a supply along with them to help build their civilization.

Biodiesel should be pretty easily accessible- whether or not in the quantities needed to supply a large naval force, though, might be up for debate.

Fair enough.  In that scenario, we're probably looking at each city being generally self-sufficient in terms of food, energy, and fuel.  Metals would be the only necessary import.

So - is there any significant basis for merchant marines here?  There would be some movement of passengers/immigrants and metals.  Perhaps it's luxury/consumer goods that are the valuable "spice" of this setting, but these could likely be shipped by small "banana boats" rather than bulk freighters.

[The Rock Doctor]

So again if its like Sea's of Venus then airplanes are a non factor not because they can't build a jet fighter its because a jet fighter is just a flying target with the type of radar / fire control they can generate.  Or is it that they have lost something after getting to this new world and they are in a neo-barbarian stage?

More the latter.  the planet's harsh enough that until recently, it took all their time, effort, and money to build and operate the cities and farms.  None could be spared on expansion-related skills, so those were lost.

I suppose if we find the scenario too confining, we can drop the "Deathworld" aspect and assume that all of the colonists regressed past early 20th century tech across the board, and are now just re-attaining that point.

[Carthaginian]

So again if its like Sea's of Venus then airplanes are a non factor not because they can't build a jet fighter its because a jet fighter is just a flying target with the type of radar / fire control they can generate.  Or is it that they have lost something after getting to this new world and they are in a neo-barbarian stage? 

Mike... let's examine the logistics of interstellar travel.
Maybe that will answer some of your questions.

These people boarded a ship that took them across at least a dozen light years of space. Now, that means that we are looking at probably 10 generations of people that have to be fed and clothed aboard ship. This is your primary cargo, and there must be a lot of it. You build a ship full of hydroponic gardens, living quarters water recyclers, etc. As a result, if it wasn't microscopic or self-sustaining, you couldn't bring a lot of extra 'stuff.' Bulky items like weapons would be carried in the most minimum amounts- you are not planning on fighting civil wars when you leave... and if you were, then you picked the wrong people to put on the roster.

When you arrive, there will only be a limited amount of things that your ship has that will move you up the tech ladder. There will be a necessary 'rebuilding period' where your tech is reduced, by and large, to the early Industrial Revolution stage- using coal and water powered machinery, wooden buildings and ships, and hand mining iron ore and coal. This will take a bit of time to achieve- all during that time, you wind up having to fight the environment. You maintain the equipment that you brought very carefully, but you can't reproduce it. You can build some simple analog computers, ballistic weapons and other things using the technical knowledge you already have, but you still can't duplicate the tech you know. Sure, you have a computer that knows everything that was on the Internet when you left Earth-That-Was... but your people live in houses built with hand-hewn logs felled by crosscut saws. Your production of iron, steel, fuel, power and your precious technical items are mostly directed to producing the tech to keep you alive and safe.

For a few decades, you live in a strange world where the elite are ruling from a high-tech citadel... but the majority of the world lives in an early 20th century time capsule. That's where we are, and where we will be until some warring power reaches critical mass- taking enough resources and population under it's influence to take society and technology to the next level.

[miketr]

Multiple ways in scifi to travel across space.

One is the generational star ship as you point out.

Another is a ship traveling at high fraction of C and time dilation effects reduce the amount of time for the colonists.

Cryogenic / Hibernation tech where the settlers were in suspended animation.

Name your flavor of FTL; maybe its stupid crazy power intensive and only works one way.  Who knows.

All have very different advantages and disadvantages. 

Michael

[Carthaginian]

Meh- I was looking at realistic ways to travel, sci-fi need not apply.
While I have absolutely no doubt in my mind that FTL is possible, I have no proof and therefore I must proceed as if it is not when planning this... so it's a generational ship operating at a low fraction of c that I'm assuming is being used. Yes, it's beyond what we can do, but not beyond what we could conceivably do.

A generation ship will work (with problems, but not insurmountable ones) and we know this- no one has got up the guts to try and build one, though... or rather, no one has been willing to strip the world of a large part of it's potential wealth and possibly bankrupt the planet to build one. Nothing else has been proven workable... yet. ;)

[miketr]

The high fractional C ship is possible.  Its all a question of energy to power the thing.  If you have space flight to the point that you are talking interstellar travel then that assumes a fairly impressive deep space presence.  Put massive solar power emitters up near the sun.  Then beam the energy to the star ship via microwave.  Just dump tons of power on it, you have the sun, the energy budget is no option during the boost phase.  Key is to be able to push the speed north of 0.9 C to get useful dilation effects.  The issue would be as the distance between the sun and space ship increases the energy beaming becomes more and more inefficient.  If you could some how get 0.995 C you are over 10 to 1 on dilation effects. 

The problem is slowing the damn thing down when you get to the other system.  What you would really need is a two stage operation.

A ship with a robot factory is sent a head to the star system; assume you can't do better than 0.2 of C.  So something 10 LYear away is a 50 year voyage. The factory ship arrives in the system and sets up a beam system on that end to provide power to allow d-acceleration when the colony ship arrives.  Then the colony ship is disassembled and they have unlimited power from the 1st ship.

Michael 

[Valles]

IIRC, it's possible to use a magnetic field (the 'magsail' type, generated by a truly enormous superconductive loop) as a 'drag chute' to slow down with.

There's also the 'sleeper ship' approach, of course, if the needed technical bits for that can be gotten to work.