Examine my proposed FTL travel mechanics

[Fred Brackin]

Originally Posted by Minuteman37

The massive SM+15 ships would be carries for many smaller combat craft, bulk transports for tons and tons of trade items, or colony ships. Journeys could take a couple of years but everyone would be living in the lap of luxury for the duration.

An SM+15 ship is 3,000,000 tons. the closet space of its' cabins adds up to "tons and tons". A single cargo hold is 150,000 tons or one space of a Hanger Bay could hold a Nimitz-class aircraft carrier. Think hard about whether or not you actually want ships this big.

If you want an FTL-capable and practical space fighter you're looking at trips of no more than 1 or 2 days at most which would make those ships (SM+5?) 350 to 700 times as fast as your SM+15 ship that takes 2 years.

Exactly how fast that minimum ship is depends on how long the distance between target systems is but for 100 light years at 2 days you're looking at 18,250 times the speed of light. That's much faster than your previous formulas have yielded.

[DocRailgun]

Aren't you concerned with the economic implications of this system?

Your worlds are going to have to be self-sufficient as noone is going to want to trade bulk items without a command economy. There may be profit in high-value items (drugs, gems, information) or even VIP transport trade, but who wants to ship raw resources (animals, food, bulk raw materials) if it has to sit in a hold for years before it can even be sold? No company or corporation of any size is going to be willing to wait for the money to come in and they certainly won't be accepting raw materials or other bulk commodities in return.

So, large shipbuilding has to be done on-site (or perhaps in-transit if you can manage it somehow). If you have slow-ish information travel time, local shipbuilding (especially large military ships), and fully self-sufficient economies that means no central government. Once a system breaks away there's little chance a central government can reclaim them - they can send massive fleets of small ships, but the local system can build its own defenses and home fleet.

Frankly, though - who wants to colonize far-flung places in this universe? Insular religious or political groups? "Back-to-basics" lifestyle groups that can afford transit on small ships? They can't take a lot of equipment, so unless you have ultra-tech fabricators to build larger and larger fabricator factories there's never going to be heavy industry.

Maybe the "Forerunner" groups that made the warp buoys also have superscience devices in orbit that can pop out ships whole- put an asteroid in one end and get a ship out? Otherwise there won't be large ships out on the Rim of Known Space (TM).

You say that the various polities are fighting over Forerunner sites - how? Small special-forces units that only have the gear they can carry with them? Noone can afford to send heavy cruisers or bulk troop transports out into the void for a political situation that started years ago.

I don't know. Fabricators seem to me to be absolutely necessary since bulk shipping is out. People in this universe have to make things they need when they get wherever they're going on a small freighter, but that means that the only profitable trade is in transporting important people or information. So, no large companies except maybe mercenary or trading guilds. Maybe an Imperial Post Office? That's the only service a central government can provide in this universe as they can't project massive military might.

This might be a good use for Icelander's Imperial uber-operators, Lensmen-type characters, or Warhammer 40K-style Inquisitors.

Originally Posted by Minuteman37

The number of systems was given so you all could estimate the approximate size of the sphere of space this is set in. Though I am being an idiot becouse I already delt with the issue of making the setting too big with too many generic meaningless solar systems. You can't Travel to a system that lacks a warp buoy so I could literally just have 3 solar systems each on a separate edge of galaxy and none of the intervening space would matter.

Ideally I'm wanting an effect where Small fighterisk ships can buzz about from one neighboring system to another quick enough that it's not unrealistic for them to partake in the Journey, they may not be quite as small as X-wings for example and could have a sort of Truckers cabin besides the cockpit, but overall not comfortable for long travel.

Tramp freighters can make longer voyages and provide comfortable accommodations for a small crew + a few passengers and cargo, they're Journeys could take weeks without resupply.

The SM+10 ships are around the size of Corellian corvettes ( according to Wookieepedia they're 125 meters and I'm rounding down as the book says I can when trying to map fictional ships to the Spaceships system) and I envision them to preform Journeys with lengths much like sea going ships from the age of sail, a couple of months to go from England to Plymouth Rock for example, and do so in comfortable conditions for all the crew and passengers.

The massive SM+15 ships would be carries for many smaller combat craft, bulk transports for tons and tons of trade items, or colony ships. Journeys could take a couple of years but everyone would be living in the lap of luxury for the duration.

[Emerald Cat]

Originally Posted by Fred Brackin

An SM+15 ship is 3,000,000 tons. the closet space of its' cabins adds up to "tons and tons". A single cargo hold is 150,000 tons or one space of a Hanger Bay could hold a Nimitz-class aircraft carrier. Think hard about whether or not you actually want ships this big.

I agree. An SM+10 ship is far more reasonable for an fighter carrier. SM+15 ships would be aircraft carrier carriers. With this setting's FTL mechanics, the SM+10 ships would be much better carriers.

For aesthetic reasons, I always set SM+10 as my largest ship size. Anything SM+11 or larger is basically a mobile small town or city. I prefer to treat objects that large as immobile space stations.

[ericbsmith]

Originally Posted by Emerald Cat

I agree. An SM+10 ship is far more reasonable for an fighter carrier.

Modern Aircraft Carriers, such as the Nimitz & Gerald R. Ford class, are in the area of 100,000 tons. That's solidly SM+12, and carriers have been steadily getting bigger over the last century. If anything being in space, and free from the limitations of gravity and naval design, will allow carriers to be made even larger. While SM+15 is probably too large for a traditional carrier role, SM+13 or maybe even SM+14 isn't out of the question. A modern carrier only has a compliment of a bit under 100 aircraft (including a number of helicopters for anti-sub and rescue); an SM+14 carrier, being 10x larger, would accommodate around 1,000 aircraft, and that's really not that many when you're talking about taking a fight to a whole other planet or solar system.

[ericthered]

Originally Posted by DocRailgun

Aren't you concerned with the economic implications of this system?

Your worlds are going to have to be self-sufficient as noone is going to want to trade bulk items without a command economy. There may be profit in high-value items (drugs, gems, information) or even VIP transport trade, but who wants to ship raw resources (animals, food, bulk raw materials) if it has to sit in a hold for years before it can even be sold? No company or corporation of any size is going to be willing to wait for the money to come in and they certainly won't be accepting raw materials or other bulk commodities in return.

So, large shipbuilding has to be done on-site (or perhaps in-transit if you can manage it somehow). If you have slow-ish information travel time, local shipbuilding (especially large military ships), and fully self-sufficient economies that means no central government. Once a system breaks away there's little chance a central government can reclaim them - they can send massive fleets of small ships, but the local system can build its own defenses and home fleet.

Frankly, though - who wants to colonize far-flung places in this universe? Insular religious or political groups? "Back-to-basics" lifestyle groups that can afford transit on small ships? They can't take a lot of equipment, so unless you have ultra-tech fabricators to build larger and larger fabricator factories there's never going to be heavy industry.

Maybe the "Forerunner" groups that made the warp buoys also have superscience devices in orbit that can pop out ships whole- put an asteroid in one end and get a ship out? Otherwise there won't be large ships out on the Rim of Known Space (TM).

You say that the various polities are fighting over Forerunner sites - how? Small special-forces units that only have the gear they can carry with them? Noone can afford to send heavy cruisers or bulk troop transports out into the void for a political situation that started years ago.

I don't know. Fabricators seem to me to be absolutely necessary since bulk shipping is out. People in this universe have to make things they need when they get wherever they're going on a small freighter, but that means that the only profitable trade is in transporting important people or information. So, no large companies except maybe mercenary or trading guilds. Maybe an Imperial Post Office? That's the only service a central government can provide in this universe as they can't project massive military might.

This might be a good use for Icelander's Imperial uber-operators, Lensmen-type characters, or Warhammer 40K-style Inquisitors.

Not so. Imagine that you can only travel in vehicles the size of trucks. Yes, it'd be nicer to move in trains and boats, but in the grand scheme of things, freight isn't that terribly more expensive.

[lwcamp]

Originally Posted by ericthered

Not so. Imagine that you can only travel in vehicles the size of trucks. Yes, it'd be nicer to move in trains and boats, but in the grand scheme of things, freight isn't that terribly more expensive.

But it still takes a year to get there. Also, the description of hyperspace made it seem like a goodly fraction of those will never arrive. This is not the sort of scenario that encourages trade.

Luke

[Johnny1A.2]

Originally Posted by ericthered

Not so. Imagine that you can only travel in vehicles the size of trucks. Yes, it'd be nicer to move in trains and boats, but in the grand scheme of things, freight isn't that terribly more expensive.

Would you like to make a bet? Trains and boats are notably cheaper forms of transport than OTR trucks, for ex, and vastly cheaper than air travel. If time is not critical, and you're moving bulk freight, a train or a boat is almost always the preferable choice if it's available.

[ericthered]

Originally Posted by Johnny1A.2

Would you like to make a bet? Trains and boats are notably cheaper forms of transport than OTR trucks, for ex, and vastly cheaper than air travel. If time is not critical, and you're moving bulk freight, a train or a boat is almost always the preferable choice if it's available.

They are indeed notably cheaper (nicer) to move in bulk, but in the grand scheme scheme of things, they don't cost oodles upon oodles more. People transported goods in that size of vehicle for years and years. I'm not saying their "just as good". They're not. They're a good deal more expensive. But they're not orders of magnitude more expensive (perhaps 1 order), and that's what would kill transportation.

Originally Posted by lwcamp

But it still takes a year to get there. Also, the description of hyperspace made it seem like a goodly fraction of those will never arrive. This is not the sort of scenario that encourages trade.

Luke

Those are bigger issues. Though if you can't guarantee that you'll arrive at your destination with that large of a frequency no one will want to travel at all: you'll be playing Russian roulette every time. Unless what he meant is you often will need manual course correction, which is a different matter.

Huge travel times are an issue. Though if we look at history similar things have been done when there were rich enough commodities. But generally its a good idea in science fiction settings to not have year long trips if you want a trading setting. I don't think the OP wants these giant trips, he's just trying to figure out the correct speed.

If I was dead set on trying to make large scale trade work, I'd set up something like a caravan, if possible, where a few dozen ships all set out at once, and we stop every 24 hours or so to check on each other, let some crews have breaks, and switch things up so there is some social interaction. And see which crews are having personnel problems so the caravan leader can work things out.

[Emerald Cat]

Originally Posted by ericbsmith

Modern Aircraft Carriers, such as the Nimitz & Gerald R. Ford class, are in the area of 100,000 tons. That's solidly SM+12, and carriers have been steadily getting bigger over the last century. If anything being in space, and free from the limitations of gravity and naval design, will allow carriers to be made even larger. While SM+15 is probably too large for a traditional carrier role, SM+13 or maybe even SM+14 isn't out of the question. A modern carrier only has a compliment of a bit under 100 aircraft (including a number of helicopters for anti-sub and rescue); an SM+14 carrier, being 10x larger, would accommodate around 1,000 aircraft, and that's really not that many when you're talking about taking a fight to a whole other planet or solar system.

I just realized that I was misremembering the SM Table. I thought that SM+11 corresponded to 1000 yards and SM+12 to 2000 yards. So I was off by an order of magnitude.

With that in mind, I'd increase my maximum ship size to SM+13. Again, this has more to do with aesthetics than realistic astroengineering. I would expect the logistics of keeping large ships fueled to be their biggest weakness.

[RyanW]

Originally Posted by Emerald Cat

With that in mind, I'd increase my maximum ship size to SM+13. Again, this has more to do with aesthetics than realistic astroengineering. I would expect the logistics of keeping large ships fueled to be their biggest weakness.

I'd expect keeping 10 SM+13 ships fueled is more difficult than keeping 1 SM+15 ship fueled. Historically, shipping has been in the largest ship you can build and have cargo to fill, because it's the cheapest way to operate. "Largest" might be limited by the amount of cargo available, the engineering limitations, or some other limit. At the moment, most large cargo and cruise ships are built to just barely fit through whatever channel they are expected to pass or the docks they are expected to frequent.