Systemwide traffic control in a star system?

[Dank Nyland]

Hi!

I'm preparing a starting adventure for my group. They get a ship via a bankrupt shipping company.
The ship is somewhere in the Garda Vilis system and the players have to find it. Of course the ship is
not at a starport and they have to do investigations to get some clues, where in the system the ship
might be.

There is traffic control for planets and starports and the COACC, but what about the rest of the system?
My question is, if there is some kind of a systemwide traffic control in Traveller for a star system?
If someone could help me out in this matter or direct me to some stuff for reading, that would be great.

Thank you!

 

[aramis]

Not likely. Why? comm-lag.
Any given world will probably make contact if you're on a course that intercepts the 1000 diameter limit (max for system forces authority)... and once you're past commit, if yoou don't have permission, see to it you don't impact... by force.

 

[whartung]

There's no reason for the rest of the system much like there's no "traffic control" on the open oceans. The need for traffic control is founded upon the simple issues of too many ships/boats/planes/cars and not enough space. It's designed to keep folks from bumping in to each other.

In open space, this is not an issue that can't be resolved with proximity sensors and the like.

 

[Dank Nyland]

Perhaps traffic control isn't the right word. English isn't my first language.

In open space, this is not an issue that can't be resolved with proximity sensors and the like.

This is more what I'm thinking about. Some kind of automated sensor system that tracks ship movement,
ship ID's and stuff like that.

 

[Spinward Flow]

Garda-Vilis wiki page

Type B starport.
Captive government (dominated by Vilis).
IISS base in-system.
Express Boat Network linkup.

Have to say that I agree with aramis on this one.
Starport (or spaceport for that matter) traffic control is going to be "local" to a particular feature of the system (mainworld, gas giant refueling depot, planetoid belt habitation, etc.).

1000 diameters is a reasonable notion of "reach" simply because beyond that distance you're talking DAY+ of maneuvering time to get there, even if comms are speed of light. Once it takes "too long" to maneuver somewhere, enforcement of government/starport authority becomes "too far away" to be useful in a timely enough fashion.

So yeah, local space authority.
You can, however contact a starport from farther away than their authority range for communications purposes, but the starport can't "order" you to change course or anything until you get within their authority range.

 

[Condottiere]

1. The Imperium runs starports for a number reasons, one, I'm sure, is to keep track of all traffic. So bring someone in traffic control or hacking into the database might be options.

2. Amateur-astronomers.net/spacecraft-spotters

 

[coliver988]

and there may well be logs of system movement: I would assume just like Earth they want to keep track of things that may end up intersecting something important. Since there is a Scout base there, one could assume that they are doing the Scout thing and tracking stuff in the system, even well beyond the 1000 diameter limit (at least that's what they do in MTU among other things). So the Scouts could be a source of info. And if that ship was somewhere near the XBoat tender it would probably notice it as well.

Side question: just how far out do those tenders go? Is there anything written about that? I would assume a good bit past the 100D limit but probably well within the 1000D limit. I'd assume that as XBoats are not maneuverable you want to have them show up well outside normal traffic patterns.

 

[whartung]

There's tracking blips of heat out in the cold dark, and there's "traffic control".

It would be unsurprising if a system authority did routine scans of the system to identify what "ships" may well be out there lurking. But as for actually identifying those ships, that's quite another matter.

If the ships are continually broadcasting their ID, then, that, too, could be tracked. If you can detect the ship using a wide ranging passive scan, it should be easy enough to point a more sensitive, direction sensor at the "blip" to read it's broadcasting transponder ID.

Even with a large amount of traffic (thousands), a system wide effort could keep up. The close stuff is just plain close and much easier to detect and track. The outer stuff, while more difficult, it going to be there awhile anyway.

Is it possible a ship could jump in and jump out of the deep system without being identified? Sure. I think that's possible, even likely. Having to have a couple of hour window of identification isn't unreasonable, and a ship could arrive and leave within that time (assuming it had fuel).

But that's ok. While the actual ship may not be identified, the scanners will certainly know there was one. Still good intelligence.

There's room for shenanigans, two ships close together, that kind of thing, but that will be cleaned up long before the ships come close to anything important.

 

[BRJN]

The freighter in question is in orbit around an asteroid. Oh BTW there are a dozen other hunk-of-junk small ships in the "parking lot" and a remote 'parking attendant' supervising the area.

 

[Condottiere]

What you want is visual, and if at any point it's in direct line of sight with the observer who has the right equipment lined up.

Unless you can distinguish spacecraft like seacraft, resonances from fusion reactors, manoeuvre drives or hull frequencies.

 

[whartung]

If the freighter is "cold", and "no one" knows where it is, it can be hard to detect. It's just going to be another "iron rich body" floating in the belt.

If it's "in orbit" around an asteroid, that must be a rather large asteroid (that would be an interesting though experiment, how big would an asteroid need to be to sustain the orbit of a 200 ton freighter).

It would not be a big deal for a ship to go "off grid" in a busy system. Likely nobody would bat an eye. It would only matter if "someone starts asking about it". In that case, they ("they(tm)") would likely have a record of its last position before it went dark. That doesn't mean the freighter couldn't have been, perhaps, towed someplace else. Also, the dynamics of the belt could suggest that just because you knew where it was, you may not necessarily know where it is. Just a lot of gravitic interactions with the other belt bodies, along with the dominant gravity wells in the system.

You may have a "general idea" to narrow it down, but not necessarily an exact position. If its in a dense area, prepare to do a lot of scanning and some flybys.

 

[Quint]

I think I remember form some supplement, that there are inbound and outbound lanes for traffic (really, think of the airspace in the immediate vicinity of an airport), and I expect that there are designated areas for "parking" - but past a certain distance nobody really cares unless you seem to be doing something hinky, and that assuming they even notice.

D.

 

[Spinward Flow]

Side question: just how far out do those tenders go? Is there anything written about that? I would assume a good bit past the 100D limit but probably well within the 1000D limit. I'd assume that as XBoats are not maneuverable you want to have them show up well outside normal traffic patterns.

CT did too much of handwave around the question of XBoat Tenders.
LBB S7 details XBoat Tenders as having 150 tons of fuel on board, meaning there is only enough to fuel 3 outbound XBoats (40 tons each) before the Tender needs to refuel in anticipation of the next XBoat to process. Of course, not every XBoat will be jumping 4 parsecs to arrive in-system, but you're still looking at a situation of being able to refuel 3 XBoats (reliably) or 5 XBoats (probably) before the Tender itself needs to make a pit stop fuel. That fuel would need to come from either a gas giant (hull configuration: 4) or a Scout base.

My point being that the Tenders don't have large enough fuel reserves to be able to maneuver far away from a fuel supply line thanks to their 1G maneuver drives (they're painfully slow). This would then operationally "tether" Tenders to the vicinity around gas giants (usually) in order to supply fuel both for themselves and the XBoats the Tenders are servicing.

However, that said ... the gas giant an XBoat Tender operates near does not have to be the one closest to the mainworld of the system. Indeed, for security purposes it would often times be preferable to set up XBoat operations near a gas giant as far as possible from the mainworld, reducing the amount of ship traffic willing to go "that far out" to harass XBoat Tender operations. Point being that if there are 2+ gas giants in a star system, expect the XBoat Tenders to "set up shop" around the "less convenient" to get to gas giant(s) for that system in order to avoid encounters with non-XBoat traffic in their zone of operations.



This is partly why my J6 Express Boat Network Ships incorporated a larger "flex" fuel capacity in the form of a collapsible fuel bladder for the cargo hold as consumables get ... er ... consumed ... so as to extend the endurance of the J6 Tenders in routine operations. Having a 220-288 ton fuel capacity on board the tender makes it possible to refuel 4 J6 XBoats before the Tender itself needs to make a refueling run. I considered this an important factor in the upgrading of J6 Tender operational security and freedom to maneuver the Tender (and its associated Armored Gigs) within their region of responsibility.

 

[Enoki]

I would think there is for any Type A starport, and possibly for most B types. The degree of control would vary with the amount of traffic in the system and work something like air traffic control does. A Type A system with numerous ships in space, and more near planets along with smaller craft like boats and grav vehicles would absolutely require one.
I can't see where ships and whatever in space or orbit would be allowed to zoom around a anything up to thousands of kilometers a second potentially without being on a predicable flight path. Accidents would be catastrophic. Running into debris, micro-asteroids, etc., would all be bad too. The traffic control system would know about these (much like weather) and direct ships and craft around such things while keeping traffic separated and moving smoothly.
The X-boats would have their area to operate in that might be much like a box in space that is restricted to other traffic. There would likely also be spots the control system uses to 'anchor' ships or park them in specific locations where they're out of the way of traffic near planets.

As for a derelict freighter... Maybe make it one of a number of plotted wrecks, navigation hazards, and other detritus lying about the system. The players (for a fee of course) can get data on all of these (numerous) things from the space traffic control authority that has them mapped. But of course, they're not too specific about what any one of these things really is as they don't care beyond it being a navigation hazard and marked.
It might even be a bit more fun for the players to find that their prize ship has been picked over to one degree or another already and is in need of some repair...

What the players were expecting:

What they find...

 

[whartung]

There's no reason to not have XBoats near the main world. No reason to have them lingering in the hinterlands. First, there's no reason to mess with XBoats. Only people that would mess with an XBoat line is either and external State threat (to disrupt CIVILIAN communication), or someone REALLY disgruntled that a message is going out that they don't want sent. And the odds of them intercepting that message are slim, and in the end all they can do is delay it. "Can't stop the signal Mal".

I mean, even today, how often do we hear about USPS or UPS or FedEx trucks being hijacked? Maybe it happens, I've never heard of it. (Who wouldn't want to hijack a truck full of iPhones!?) I'm sure someone is crazy enough to try it. But, no, rather than punishing the messenger, they go to the destination and intercept it there.

XBoats are Imperial. Mess with XBoats, and the Imperial Navy comes knocking. This isn't some backwater naval patrol with no budget protecting an E starport with 10,000 denizens. The Imperial Navy do not have a sense of humor, nor a sense of restraint.

 

[Condottiere]

Tenders should be stationed for the best direct line to the next destination; possibly several along a busy intersection, plus one or two spares, since you don't want the routes disrupted due to a malfunction.

 

[whartung]

XBoats are not the pony express. When an XBoat is ready to go, they go. When an XBoat arrives, it arrives, it's processed, and then they're sent on their merry way. There's slack in the system. There has to be, especially if they're trying to keep any kind of schedule. (Like one boat a day.)

Don't forget jump has that +/- 17 hour time window on arrival. So any schedule shorter than 34 hours necessarily needs to have extra boats, plus you have to have extra boats for maintenance windows anyway.

Park the tenders near the primary world. When the XBoats show up, fly the tender over, round up the Boat, feed the pilot, fuel it up and it's ready to go. If it's a really busy system, station more tenders. They have plenty of time to manage this. There's no critical time crunch.

The comms will beam the messages upon arrival from anywhere in the system.

 

[giant.robot]

Most (if any) systems aren't going to have deep space "traffic control", space is really big. You'd have traffic control near a habitable planet or space station or some specific destination for safety reasons but outside of that it would be a free for all with some common conventions governing behavior. I would though see one of those conventions being running a transponder and announcing arrival and departure from a system. This could just be a tight beam transmission to the system's biggest spaceport. Lien holders on ships might get nervous if they don't at least have some idea of a ship's whereabouts.

So searching for a ship parked out behind an asteroid, characters might be able to go through spaceport records and see the ship announced its jump into the system, a record of refueling (or maybe no refueling so it's still in-system), and no announcement of jumping out. It's last transponder ping was at coordinates x,y,z and the doppler compensation suggests the heading was A. A little more investigation finds the chief engineer sent a tight beam message to a station on the main world's moon to place a bet on some sports game a day after the last transponder ping and it came from the vicinity of some large icy asteroid which matches with the heading calculated from the transponder ping.

Just a note, a lot of traffic monitoring here on Earth of aircraft and ships is done with passive radar. Transponders send out identifiers with telemetry which are just picked up by networks of passive receivers. This is called secondary radar, primary radar is where a radar transceiver is actually pinging out a radio signal to bounce off the hull of the vessel. Primary radar is used in closely controlled areas where really precise locations are necessary. Secondary radar is used everywhere else since the location tolerances are much looser.

 

[Spinward Flow]

XBoats are not the pony express.

Uh ...

LBB S7 p8

The entire network operates like the pony express

You want to try that one again?

 

[whartung]

Well this suggests that there is an idle XBoat for every arriving XBoat so that it can jump as soon as the other arrives. Which still suggests that there's little rush to get to the arriving boat.

Boat arrives, beams messages to the tender, which downloads it to the waiting boat, which jumps. Now there's a window of maintenance and downtime (like, say, the pony express!) for the arriving boat. And there's no need to transfer the pilots (in fact it's inefficient to do so as the exchange of the pilot to the next boat can just take too much time). XBoats stand by, pre-crewed and jump when loaded.