System Traffic/Ship Volumes and Numbers

[Franbo]

Hello all,

About to start a campaign (Mongoose rules, circa 1105 and primarily Imperium Fringe based it if matters) and am trying to find out if there is a simple outline anywhere of "average" system traffic and/or number of ships based purely an a world uwp code and bases present.

I have managed to find some good guidelines for developing complex trade route numbers and volumes between planets, however since the campaign isn't really a trading-based one I am not keen on having to put in the time/effort for that complex an approach.

Essentially I am looking for something much quicker/lighter to provide a rough outline for number and types of ship in the vicinity when players arrive at a system (both interstellar and local).

Is anyone aware of something like this existing somewhere already?

Franbo

 

[Reynard]

Hard numbers I doubt. I suggest looking at the sector or subsector your campaign involves and surveying the starports classes and the vicinity to each other. The better starports will attract greater traffic but it's also important to see how many and how close other systems are. An A class port with few close stars isn't going to have much business. Ideally, the best served ports have Jump 1 and Jump 2 neighbors and the greatest traffic. Population will also factor in as it encourages higher trade needs to a system. Treat systems as towns and cities. A class starports on a Main are bustling with ship traffic while backwater C class see infrequent deliveries from Free Traders.

You mentioned a Fringe setting. I assume you mean near a border region rather than systems with low populations and lesser starports which would give system encounters a wild west backdrop. Otherwise, it's still based on what is there.

 

[phavoc]

As far as I know there isn't anything. I'd say it all depends on the location the players are at when they arrive. Bigger = more traffic, smaller = less traffic. The type and amount is going to be dependent upon the size and nature of the place. Obviously starports will get the most, and the primary system starport will get the most traffic. Military will be more or less ignored unless your players are going into the piracy business.

And you have to ask yourself do you wants lots of smaller ships or fewer, but bigger ones? If you use modern analogues, you have the great big super-freighters that carry thousands of containers or millons of tons of oil, but they only deliver to the bigger ports and locations. Much smaller ships take everything to and from everywhere else. So if you have a smaller world, assume you'll have more but smaller ships. Do some hand-wavium and put out what you think the local area would support at any one time. You'll need to figure out a little bit about the rest of the system if you want to come up with a model of sorts for all the in-system traffic and routes.

 

[dragoner]

Essentially I am looking for something much quicker/lighter to provide a rough outline for number and types of ship in the vicinity when players arrive at a system (both interstellar and local).

There are various ship encounter tables out there, for a general description, Starports is rather nice, as well as Starport Encounters, good for on the ground roleplaying. Otherwise it's the stuff off of page 69 of the rulebook; however that doesn't say you can't just create some stuff a make it appear random.

 

[Matt Wilson]

This is kind of a ballparky answer based on some of those trade route rules (Gurps Traveller: Far Trader).

Say you have a high pop, decent tech world, like pop-9 and TL C.

If there's another world of equal pop/tech in that subsector, there's probably enough goods leaving each day to fill 5-6 heavy freighters. Specifically cargo bound for that world. More than that if there's some clear supply/demand between their codes. Worlds of that size in a neighboring subsector will drop that number down to maybe 1-2 per day. Beyond that distance, worlds will only be interested in very specialized goods, as there's probably already a Pepsi bottling plant nearby, etc.

Again, that's pretty loose ballpark stuff, but you can probably use that to eyeball your sector and do a little quick math. Three pop-9 worlds in your subsector? Each one maybe has ten heavy freighters in port at any given moment -- or the equivalent in larger/smaller cargo ships, like maybe 5 heavy freighters, 12 subsidized merchants.

That number drops drastically based on population -- since pop-8 is 1/10 as much as pop-9 and pop-7 is 1/100 as much. So cargo from your pop-9 world to a nearby world that's only pop-3? Probably only enough freight to fill one type-A free trader every week. And there's probably hardly ever freight directly between two pop-3 worlds.

I'm not sure about military or "customs" ships, but again it's probably proportional to world population and starport class. Maybe a site like the US Coast Guard might provide some insight there, adjusting heavily for the high cost of starships. Look at what ships (boats and cutters) are available at a big port like Long Beach for starters.

Hope that helps.

 

[Pyromancer]

13Mann sells the fabulous "Excellent Maps for Explorers and Merchants" that has this type of information color coded on a beatiful map (reverse side shows the political situation):
https://www.13mann.com/index.php/de/webshop-de/product/view/4/75

It uses the 1115 post-5FF data, but the changes are not very big.

 

[Franbo]

Those are some useful responses there.

I am fine with figuring out "significant random encounters" using the encounter tables, Starports and creativity to tie in with the pacing of the main story arc (I.e. Breeze through an arrival/departure or make something exciting happen), It's more a general atmospheric guidance I am trying to pin down... For example:

Something that tells me... 15 shuttles, 5 small traders, 4 freight haulers, 1 passenger liner and an SDB.

I can ad-hoc convert this to something more interesting like...

"The first post-jump sensor sweep shows 20 or so traces. There are over a dozen small craft, mostly shuttling between a handful of small trading vessels and three cargo haulers around the Starports, with a passenger liner on final approach. Four shuttles seem to be heading out towards the gas giant, likely towards that moon orbiting around it, on parallel courses to the hydrogen hauler heading back in-system, while an SDB seems to be sweeping through the Trojan point."

... and if I'm feeling nasty...

"Although your attention is drawn more closely to the 400 ton Sub-R whose signature just spiked as it accelerated towards you on an intercept vector, the automated threat receiver pinging as icons appear for turrets popping out of the hull"... make me a tactics roll please Jack... "The comms unit beeps as you get an incoming hail from the approaching ship..."

I just have no idea what is "realistic" in terms of numbers of "ambience" ships to build in to the descriptions. In all likelihood none of the players will consciously notice (or indeed care), but it makes me feel better to have some kind of metric rather than just randomly making it up.

Those ballpark figures are useful, I suspect I may need to track down a copy of Gurps Far Trader after all to flesh out some details after all.

That map is very nice indeed!

 

[Rikki Tikki Traveller]

Sorry I cannot give proper credit for this idea...

Someone somewhere posted the idea of adding a Trade Index to the UWP.

Take the square-root of the Population times the TL. It gives you a good general feel for how much trade is moving in/out/through the planet.

 

[phavoc]

Those are some useful responses there.

I am fine with figuring out "significant random encounters" using the encounter tables, Starports and creativity to tie in with the pacing of the main story arc (I.e. Breeze through an arrival/departure or make something exciting happen), It's more a general atmospheric guidance I am trying to pin down... For example:

Something that tells me... 15 shuttles, 5 small traders, 4 freight haulers, 1 passenger liner and an SDB.

Ouch. That sort of detail would be hard to come up with in a simple table format. To do it with dice you'd need pages of possible traffic encounters (if you ever played D&D there were some treasure supplements that did this). If you went through this route you COULD create a number of variable encounters linked to starport sizes, with adjustments perhaps for trade codes, population, distance to other potential trading partner planets, etc. But it would be big and possibly unwieldy.

This is something that is definitely crying out for automation.

 

[Franbo]

This is something that is definitely crying out for automation.

Definitely! That said, I would apply that statement to many things in Traveller .

 

[locarno24]

In addition to the encounter tables in the rulebook, you could have a look at the "Pirates Of Drinax" campaign supplement (look on the main mongoose page) - it has rules for what traffic you encounter in a system based on whether it's a major system (on the trade route) or a minor system, or a naval base, and so on.

Results vary from nothing to light freighters to 1000dTon heavy freighters, up to massed convoys replete with escorting light warships, and even navy patrol groups.

Plus it has rules for how quickly the patrol will come down on you if you start something...

 

[GypsyComet]

If you assume an X-Boat a day for each leg that comes into a world that gets you just the news service frequency, implies Tender populations, and, if you do the math, means a LOT of X-Boats, even for a half-sector like the Marches.

If you then want to assume that the Scouts also maintain a secondary News feed using Scout/Couriers off of each X-Boat node, those can also add up to a LOT of Scout ships. The secondary web needn't even be daily to add up to thousands of Scout ships per sector. No wonder they have them to hand out...

 

[sideranautae]

If you assume an X-Boat a day for each leg that comes into a world that gets you just the news service frequency, implies Tender populations, and, if you do the math, means a LOT of X-Boats, even for a half-sector like the Marches.

If you look at the MGT jump rules and extrapolate further; The X-boats will be jumping in all over the system. Days from the Tender and days from each other. It would take many Tenders even for a system with a moderate amount of X-boat traffic.

 

[Rikki Tikki Traveller]

Check out Issue #51 (Last Month) of Freelance Traveller.

There is an article in there about the Eaglestone Trade Index. It does what I think you want. It provides a way to estimate passengers and trade volume between systems. It also discusses ways to adjust the index for your setting (High or Low volumes).

Might be just what you are looking for.

 

[Reynard]

From what I gather from the rules, the time factor is the most inaccurate portion of a jump compared to the exit point. When an Xboat is launched it's going to arrive at a well known, pre-determined place near an Xboat tender the majority of the time. Tenders can't be spending their days hunting for frequent strays. Those tenders are there to make sure the boats are at peak performance and have the most accurate astrogation data, well tuned engines and refined fuel.

If you were allowed to be within visual of a tender. It probably resembles a miniature airport of activity with Xboats and Couriers docked outside and repair drones buzzing about or in the bay for service. If you're lucky, you see a craft detach and enter jump space or blink in from jumpspace and the tender maneuvers to it for a docking clamp. This would probably be near the 100d limit not for the Boats and Couriers but for transmitting data or shuttling materials to and from planet side. For some, this would be a sight of a lifetime.

I would suggest these tender locations are near but at a safe distance from highports especially considering express route are commonest at Class A ports. Might have a view from the highport like a hotel near an airport.

 

[sideranautae]

From what I gather from the rules, the time factor is the most inaccurate portion of a jump compared to the exit point. When an Xboat is launched it's going to arrive at a well known, pre-determined place near an Xboat tender the majority of the time. Tenders can't be spending their days hunting for frequent strays.

Based on the MGT Jump rules, an X-boat with an Engineer (Jump Drive) - 2 person will experience an "inaccurate jump" ~20-25% of the time. This means that 20-25% of the X-Boats will end up DAYS away from the X-Boat Tender.

That frequency jibes with what I experienced in game under similar circumstances.

NOW the fun begins. After the first X-Boat ends up days away the Tender will start running to get it. (Let's assume it is a slow system and only one boat/day) The next days X-Boat is now almost 100% guaranteed to land days away because it doesn't know where the Tender is, as it has taken off after the Boat that jumped in the day before...

So, X-Boats start stacking up adrift. :lol:

 

[Reynard]

Sounds like time to scrap of the whole Xboat idea. Unworkable for thirty years! Bulkier ships with jump 3 or 4 drives will have to replace them; at least when they fail 25% of the time they just burn more fuel so the cost of data and material delivery needs to go up too. The express boat system is mere window dressing anyhow.

I wonder how many ships in general, and they usually have worst skills, end up deep in gravity wells at vectors?! Another reason to have zero vector before jumping.

 

[sideranautae]

Sounds like time to scrap of the whole Xboat idea. Unworkable for thirty years! Bulkier ships with jump 3 or 4 drives will have to replace them; at least when they fail 25% of the time they just burn more fuel so the cost of data and material delivery needs to go up too. The express boat system is mere window dressing anyhow.

I wonder how many ships in general, and they usually have worst skills, end up deep in gravity wells at vectors?! Another reason to have zero vector before jumping.

Yep, redo the whole shebang. Bigger ships carrying high priority cargo and all the digital data.

 

[GypsyComet]

Bigger ships carrying high priority cargo and all the digital data.

To the people who set up the X-Boat network, the data IS the high priority cargo.

The solution is to increase the number of Tenders and have a working reserve of X-Boats. Tenders can carry as many as four X-Boats, and with a little working reserve can still easily launch one a day while retrieving the incoming. With an extra tender (assuming 1.5 per leg with a minimum of +1) you can have a fairly efficient outfield and always have the X-Boats handy to hit the outbound trails.

This only addresses those systems on the X-Boat routes, though.

 

[sideranautae]

The solution is to increase the number of Tenders and have a working reserve of X-Boats. Tenders can carry as many as four X-Boats, and with a little working reserve can still easily launch one a day while retrieving the incoming. With an extra tender (assuming 1.5 per leg with a minimum of +1)

In a fairly busy system you would need more than 2 Tenders. Easier to build an X-boat with M-drive. Also, in a fairly short time period (given a large empire) X-Boats will be crashing into GG's before a tender can reach them. NOT a viable situation.