Orbital refineries

[Liam Devlin]

Aramis is correct--
Area denial is the key to beating an enemy force "jumping in" to the GG's. Eventually,, they can run out of fuel if they don't blow their way past you..MG monitors, even planetoid hulled ones, can do the job.

good shtuff.

 

[Malenfant]

I'm with Anthony on this, it's impossible and futile to defend all gas giants and prevent enemies from jumping in and refuelling.

Heck, try and do it in our own solar system. We have four gas giants here, ranging between 5 and 30 AU from the main world (Earth). Assuming Imperial TL's, you can still only put a finite number of ships around each gas giant, and the more remote ones are going to be harder to resupply.

Say a fleet comes in at Neptune. The nearest other planet is a minimum of 10 AU from Neptune. So it takes any other planet at least 80 minutes to even notice that a fleet's arrive (if it can even detect their arrival) since the light of their arrival needs to reach them. So you're relying on a detector at Neptune itself to mobilise a local fleet of SDBs... which would be trivial to throw off with a decoy.

I don't see why you couldn't get some decoy ships to jump in far from where the real fleet is going to be. The SDBs can use up all their fuel getting to them (and of course the decoys leave or blow up in their faces or do something equally annoying), and meanwhile the real fleet can show up on the other side of the planet and do a quick refuel (and you can bet they'll probably have fuel refining plants on them if they've got any sense) and be out of there before anyone has a chance to react.

Or something like that anyway. I'm sure it should be possible to use decoys to mislead the local defences long enough for the real fleet to get in there and out again.

 

[Piper]

Here's one take on gas giant defense: Link

Results will vary depending on fleet design, but tankers are generally cheap to build.

Stellar "geography" would seem likely to play a big part. Defending multiple gas giants in a single system is unlikely to be profitable.

On the other hand, in systems where the "mainworld" is a barren rock, the gas giant might be the only thing worth defending.

On a related note, the Traveller Book gives the average time for skim refuelling at 8 hours. Are there any sources that support/contradict this?

Also, does anyone have an idea on what kind of limits might be placed on a ship engaged in skimming?

 

[Ran Targas]

^ That's an interesting article; strategy anyone who has played Risk or Axis&Allies can understand.

I still hold that with the volume of space being considered and the amount of radiation, dust, micro-meteors, macro-meteors, moonlets, moons, etc. winging around, keeping a clear sensor picture may be more difficult than let on. And with every false target requiring investigation (just in case), the fleet of defenders grows larger and larger until it becomes uneconomical; particularly while trying to maintain a proper defence for rest of the system.

 

[Scott Martin]

I still hold that with the volume of space being considered and the amount of radiation, dust, micro-meteors, macro-meteors, moonlets, moons, etc. winging around, keeping a clear sensor picture may be more difficult than let on. And with every false target requiring investigation (just in case), the fleet of defenders grows larger and larger until it becomes uneconomical; particularly while trying to maintain a proper defence for rest of the system. [/QB]

I think that the difficulty in bridging Aramis' (and oher "Hard" SF folks) view and yours may be due to the fact that in the Real World (tm) space is big, empty and cold. Stuff "whirling around" like in the Empire Strikes Back is not realistic, even in the densest parts of the asteroid belt.

If I'm looking for a "threat" around a gas giant, I will grant for the sake of argument that there is a moderate amount of "clutter" within ~1 ls of a gas giant (In reality this "clutter" will not interfere with my sensor operations at all) This "Clutter" is guarenteed to be out of "jump" range anyway (any hostile target trying to get in to the gas giant needs to enter several light seconds out if you are using Gravity-based jump masking, or a LONG way out if you are using diameter based masking.

So given that your "bogie" has to penetrate this area to refuel (and we'll pretend that this can be done as a quick "skip" at orbital velocity)

How are you going to hide?

Any planetary body at this distance from the sun (far enough not to blast off seas of hydrogen)will have a surface temperature of ~20-100K. Your ship with it's very warm fusion plant needs to have a radiator that is kicking off at least several hundered K, and probably into the thousand K range, while the skin temperature of your hull is probably in the range of 200 K (the temperature of any crew compartments is ~293K, AKA 20 degrees C)

All I need to look for is anything that is more than 3m long with a surface temperature above 150K (as pointed out, easily done with a small IR CCD at current TL)

If you want to play the "but I'm radiating the heat away from the detectors" game (this is called "EMM" in TNE) The detectors that we are talking about could easily fit in a self-cntained bouy smaller than 1 m in diameter, and if solar powered (yup, they're *really* low power) would conveniently be below your "targeting threshold" (smaller than 3m, cooler than 150K) so they also wouldn't "clutter" the targeting environment, and if you are radiating all of your heat away from where you think the detectors are, you are radiating it *towards* something in the sphere of detector bouys.

This all assumes that you can get ALL waste heat directed away, even with some ultra-cool unobtanium I can't see any wy to mask the thermal output of a smal star (AKA your fusion plant)

FYI this is why major navies stopped building big ships for naval superiority missions: it's really easy to fire a swarm of missiles over the horizon with IR trackers set to engage anything big and warm: even the Kirov class sticks out like a sore thumb on the north Atlantic despite a LOT of work on passive countermeasures.

You also need to figure out how you are getting to the GG: either you're accellerating (at which point your drive emissions are probably going to stick out like a sore thumb) or coasting (in which case it's either days for you to be detected, or you're using your drive to slow you down so you don't go *SPLAT* when you try to refuel. So either there is a *tremendously* long detection window, or you are a trivially easy detection target.

I suspect that defending gas giants is more like defending a bank: light security and cameras so that you deter "casual" theft and have pictures of the folks who brought enough firepower to defeat your security anyway, but if the other fellow brings a tank, your guards should just bail. GG defence would thus be a picket (or customs partol) to make it hard for enemy scouts to get a read on your system defences, but not enough strength to actually slow an assault.

Scott Martin

 

[Scott Martin]

BTW IMTU the "refineries" are on the surface (Methane oceans) and have an orbital "tank farm" where ships can refuel.

Easy enough to vent the tanks if an invading fleet arrives, and the bottom of a GG gravity well is not somewhere most navies want to fight.

Invaders would take the mainworld and then call for the surrender of the refineries, since they are trivially easy to blockade from resupply, and expensive to rebuild.

They also offer wonderful adventure possibilities, especially when you keep reminding the players (with various creaks and groans in the infrastructure) that the outside pressure could crush them like a bug. Excellent place to do a "bug hunt" and search for mad scientists (or serial killers)

If you want an idea of "atmosphere" read the SF book "Starfish" which takes place largely in a deep ocean research station.

Scott Martin

 

[Malenfant]

I think people are going to lob this argument round and round without resolution unless someone actually comes up with hard numbers based on reality.

There's a lot to account for here, including:

- the numbers and capability of the invaders and defenders' ships
- number of GGs in the system
- detectability of KBOs (which is actually really easy - look for dust disks from nearby systems).
- the volume of space to defend
- quite how anyone is going to stop a fleet from refuelling in the first place
- how long refuelling takes from start to finish
- what the defenders have in place to detect invaders
-what countermeasures the invaders have to obfuscate their presence or defeat detection methods
- lightspeed communication and sensor delays
- lots of other points too...

What I'd suggest is to run with two systems. The first system is the Sol system - we know a lot about this system, we know where the rings and moonlets and hideyholes are, and we have four GG's to defend. So make some realistic assumptions about what the defenses of the Sol System in IY 1100 or whatever, make an invasion fleet, and then see what happens. You can change the defensive positions with each run of the scenario, with all the defenders around Terra (which would be the most sensible IMO), or with some around each GG, or whatever. Leave no stone unturned in all the considerations, and see if it works.

The other scenario to run would be a fictional system with one GG. There'd be a lot of variation here, but I think an M V star with a tidelocked mainworld and a single gas giant about 1-2 AU from the star would be a reasonable one to start with. Again, run the scenario with as many different starting defensive configurations for a given invader fleet as possible and see what happens.

It'd be a lot of work but I think that's the only way to really figure out what would work and whether it really is worth defending GGs. Personally my initial feeling is that it isn't worth it and it would be impossible to do anyway. But if something turns up in the process of examination that uneqivocably proves that feeling wrong then I'll happily accept it.

 

[Liam Devlin]

In defense of imagination vs. Hard Science.

This is best resolved with your own powers of plausibility/ communications to your players in-game.

We take into consideration the facts of detection ranges, (passive or active) means of detection, and the system's population & numbers of defenders.

In a multi-GG system with low population (0-4) free refueling reigns, with minimal patrolling by Imperial Navy (if we are to use the Imperium 1st-2nd-3rd-4th examples) on an irregular pattern.

Likelihood of wilderness refueling for free: Extremely high, IMO.

Systems with multi-GG and Pop 8-A, and stellar capability (TL-7 or 8 depending on Traveller RPG flavor), do like Scott Martin has suggested--lots of passive detection systems, and SDB bases at GG moons for early interception.

Systems without Naval bases/ Scout bases vary to level of control measures taken. A hint at System/ mainworld LL maybe gleaned for new GM's looking at this fresh on how hard they might apply the law vs free refueling if they have orbital refineries at all.

Those with bases, or owning own system Navy..well, thats a YTU answer guys, ladies. Apply as you will, and be ready to defend your approach plausibly, logically to the players who sharpshoot your way of thinking. This isn't ADnD and saying "its magic", after all.

Mal & Aramis & others above both have valid points when it comes to explaining detection vs stealth technology. IYTU you will have to make stands and compromise for storyline/ plot vs Science sometimes.

Mal's idea is good for opposing views, and a wargame scenario. Sorry, I haven't the time to participate, but others may take up the gauntlet and try their hand at it. The results should be interesting.

Tactically speaking, a small polity can accomplish this. The Imperium with its 11,000 worlds, well..not all worlds have the criteria we've discussed, so you get two answers, and reasons why pirates, raiders, cursory invaders etc avoid patrolled systems and pass through the lightly held ones.

In the end, Its still YTU.

Lovely day isn't it?

 

[Liam Devlin]

Originally posted by Scott Martin:
BTW IMTU the "refineries" are on the surface (Methane oceans) and have an orbital "tank farm" where ships can refuel.

Easy enough to vent the tanks if an invading fleet arrives, and the bottom of a GG gravity well is not somewhere most navies want to fight.

Invaders would take the mainworld and then call for the surrender of the refineries, since they are trivially easy to blockade from resupply, and expensive to rebuild.

They also offer wonderful adventure possibilities, especially when you keep reminding the players (with various creaks and groans in the infrastructure) that the outside pressure could crush them like a bug. Excellent place to do a "bug hunt" and search for mad scientists (or serial killers)

If you want an idea of "atmosphere" read the SF book "Starfish" which takes place largely in a deep ocean research station.

Scott Martin

I have used robotic refueling stations as an explanation to gamers for some of the refined fuel starports (C, B, A) in the very low populated systems of UWP, or those without GG's, and say, a water world that submerges, and climbs back up refining in the trip to orbit for the vessel to tank up at.

Recently in our TNE campaign, my Co-GM took a line from me, and used one for the Vampire fleet we encountered (and hid from!)in what we thought was a safe system (a collapsed but habitable water world with no GG at all). The VF used their smallcraft as shuttles however since the robot station had lost the ability to use its CG to climb to atmsphere and met them there.

 

[Malenfant]

I don't see that there's any conflict between "plot vs science" at all. Fact is, while thinking through things realistically may remove some options that turn out to be unrealistic, it often creates new ones that you hadn't considered before because you hadn't realised they existed. I've noticed that time and time again, but IME most of the resistance I've seen from other people comes because the ideas that they came up with proved to be unworkable in a realistic setting and because they're unwilling to see or try the other cool ideas and plots that arise because of that realism.

The only difference really is in the amount of thought you want to put into it. If you just want to whip something up on the spur of the moment and don't care whether any of it actually works in reality you can do that, though then you're opening yourself up to players who might go "hey, wait a minute, that doesn't make any sense!". Or you might find an inconsistency yourself that you overlooked that puts you on the spot. Thinking things out realistically takes more time and effort but if you do that it's a lot harder for players to poke holes in what you come up with then.

Either way I think it's no problem to come up with an interesting, exciting plot against a realistic background. It's quite possible to have the best of both worlds, if you don't close your mind to the opportunities provided by both.

 

[RandyT0001]

Orbital refineries, sure. Some defenses and sensors for protecting the refinery and deterring illegal skimming, sure. Most of the system defenses are going to be around the mainworld, that's usually the economic reason for invading in the first place. So a free trader illegally skims what to do? Answer, the locals review the sensor logs and find out the offender's transponder code and put up an in system APB so that he's caught when he returns a couple of months later selling his spec trade goods.

Economics drive what is protected and what is not. If it makes economic sense the GG will have considerable defenses otherwise the mainworld gets the all of it save for a few score of SBD's to patrol the GG's. Governments won't put alot of money and resources to defend things that are basically impractical to defend. If the GG is the most important thing in a system, if it's the lynchpin of strategic defense for the Imperium in the sub-sector then the Imperials station a fleet there.

Well, that's my $0.01.

 

[aramis]

The GG is the "Hostile Refueling Point of Choice" because of detectability and usual duplicates, at least in the OTU.

A Fleet which jumps in is usually tanks-dry, refuel or die. Not always, but usually. Since they must refuel, they must seek known source of fuel. While there are many, the ability to refuel from a GG with fuel shuttles is FAR faster, much less manpower intensive, and only slightly less dangerous than refueling from KBOs and OCO's. Further, the position of GG's can be calculated within a jump-frame from several parsecs away (AM1). Smaller worlds would require interferometry; while plausible, that would likely be specialized ships only.

Defensive fleets at a GG would be of three basic types: Notifiers, local defense dedicated craft (monitors), and Jump capable combat craft. Notifiers task is to ID and disperse incoming.

The other two provide local interdict if needed for commercial shipping. Against military invaders, however, their roles are less certain. Monitors are likely to put up solid defenses or not engage at all. Jump capable ships are likely to engage, and attempt to take out a specific portion of fleet strength, and be ready to jump at any point. If they're winning, they won't. When they start losing, they will jump back to some other system.

The reason for needing to picket GG's is simple: if you don't, you have no borders. With no borders, you have no definition to the polity, and hence no Imperium.

 

[Malenfant]

The reason for needing to picket GG's is simple: if you don't, you have no borders. With no borders, you have no definition to the polity, and hence no Imperium.

That's not true - borders can be defined by the orbital space around the mainworld (or other inhabited worlds in the system).

One variable with a GG refueling is whether defending ships can even get to the invaders in time to do anything to them (and with enough fuel too).

If it requires specialised ships to make the finer observations of a nearby system, then so be it. An invasion force is going to be phenomenally stupid if it just jumped into a system with the minimal amount of information. If it's a totally unknown system then they're going to observe it for a while and gather data first, but 99% of the time there's going to be pretty much no excuse whatsoever for them to not know exactly where the belts and small icy worlds are because that is going to be public knowledge anyway. There's no reason for them to be unaware of exactly where every available fuelling point is, which makes it less likely that they're going to try to refuel at the most obvious spots. And given Imperium technology, I'm sure that they'd be quite capable of refining astronomical techniques known today to be able to see where all the planets and dust/comet belts are in nearby systems anyway.

They're also unlikely to be jumping in without fuel refineries in tow (again, because they'd be dumb if they didn't), so any source of hydrogen will be viable.

 

[robject]

Defenders could work their way around a GG in a couple of hours, couldn't they? So if a fleet can refuel in less than, I don't know, 3 hours or so, the invader is OK, otherwise aren't they a bit more vulnerable than normal?

I agree with the pre-jump reconnaissance. Gotta know as much as you can, in the time permitted.

I wonder how much of a system's defensive forces "ought" to be allocated to a GG? Don't want the mainworld undefended, but one wouldn't want an easy source of fuel for bad guys. Interesting problem.

Another set of good points from Mal. An attacking force won't jump in dry if they don't have to -- they'll have supply lines, even if only in the outsystem, won't they?

Seems reasonable to me that refueling by hostile fleets is only a minor problem at worst.

 

[The Oz]

There's a trick I've allowed in my TCS campaigns to allow fleets to enter enemy space with full fuel tanks, even after a max-range jump.

It involves using tankers as "self-propelled L-Hyd tanks." The fleet connects to the tankers (using really =long= hoses) and uses their fuel to charge the jump drive, then jumps. The tankers completely refuel and follow later, arriving (hopefully) in a system already secured, but with enough fuel to jump out if the system hasn't been secured.

 

[Pickles]

I would have thought that any hostile fleet jumping into a system would do so with enough tankers to refuel and leave if they have to. A 'find a place to refuel or die' policy would be too foolhardy for the most megalomanic Vargr.

 

[aramis]

One of the best motivations for military success is making attacks on a "Win or Die" basis. It is counter intuitive to the non-military mind, but desperation makes or breaks combatants. Any serious deep probe invasion operates under win-or-die orders.

Also: Borders are contiguous to a polity. The US effectively has at least sets of borders: one for the Contiguous 48 states, another for Alaska, another for Hawaii, another for American Samoa, Another for Puerto Rico, another for the US Virgin Islands, and yet another for Guam.

If the worlds are the borders, you have no overall area denial at all. In exactly the same sense that the Hawaiians had no border for their kingdom, since they could project not effective force off the land of the islands.

If I have an empire, but I can't prevent the capital from being attacked, I have no borders.

The Oort and Kuiper belts are, as stated in other threads, canon-breakers, as are undefended GG's. If there are fuel sources that are readily detectable at distance, and are not interdictable, you can not prevent deep strikes to any location in the empire. At best, you can give an hour or two of notice.

Every major fuel source must be accounted for. Hence, IMTU, Kuiper belts were routinely cleared by the 1st Imperium... in order to create a border.

If a fleet can bypass* any given system at will, then no system is safe from assault, and borders become immaterial. In fact, the realities of Traveller's board games imply that there are not normally Oort nor Kuiper belts, or alternatively, that they can not provide fuel sources. (It doesn't matter why there are none, just that they are not a fuel source available, either by lack, or by incompatibility.)

* enter, refuel, and exit without combat counts as bypassing for this purpose.

So, either the 3I Does defend the GG's, or every world must be prepared to repel any reasonably strong force.

 

[Malenfant]

Seems to me that every world must be prepared to repel any reasonably strong force then. You can't prevent deep strikes to any location in the empire, because you can't cover all the refuelling points.

Seems to me that the best you can do is focus your forces on defending the actual final objective of the enemy (ie the mainworld, usually). That should discourage them from attacking it - and if they start setting up a base elsewhere in the system from which to launch an attack then the defenders have plenty of opportunity to amass and attack from the homeworld.

Forget borders and any assumptions based on terrestrial combat or history - at best they're just lines on a map. For example, we already know that deep space jumps are canonical, so that alone can bypass polity borders easily.

Either the OTU works like the real universe (in which case systems have oort clouds, comets, icy bodies, and loads of other places to refuel from) or you have to accept that the OTU's basic physics is completely and arbitrarily different to that of the real universe (since all those sources don't exist). Basically, they don't exist in canon because MWM et al didn't do their research and/or chose to ignore them, because those alternate sources were known about at the time (it was known that icy satellites existed anyway).

Rather than trying to find ways to force a scenario that is based on flawed assumptions to work, how about trying to find ways to make that scenario work plausibly given what we know about how things really work? Otherwise you're just opening yourself up all the time to people blowing holes in your logic (which is already happening).

 

[Piper]

Ice mining for fuel was covered in Beltstrike and, I believe, in the JTAS "Mining the Asteroids" article.

 

[Liam Devlin]

Originally posted by The Oz:
There's a trick I've allowed in my TCS campaigns to allow fleets to enter enemy space with full fuel tanks, even after a max-range jump.

It involves using tankers as "self-propelled L-Hyd tanks." The fleet connects to the tankers (using really =long= hoses) and uses their fuel to charge the jump drive, then jumps. The tankers completely refuel and follow later, arriving (hopefully) in a system already secured, but with enough fuel to jump out if the system hasn't been secured.

I watched the history of the oil business and tanker ships the other day. Learned a few new things, and reading your post reminded me of a few of 'em, the Oz.

CPT Chester Nimitz, USN (later Admiral) perfected, and then performed the first refuelling at sea in 1916-17 or so for convoy escorts in WW-1.

This became the basis of refuelling at sea for the USN throughout the next WW(2), and even today, it is a measure employed when time in port is not achievable and the fleet must get from A to B without delay.

In the space Navy, we have canon Fleet tenders/ fuel ships, and thus we have deep space refuelling/ astrogation all the way up to the 1248 TNE books.

Or just how did the Zhodani suddenly appear at Roup in the initial days of the FFW? Reconnaissance, and deep space refueling with tankers, and a secure supply line.

Or hold the outer system of Imperial Efate, and thus the mainworld in siege for the duration of the war? Not to mention threw back three attempts to lift the siege. Area denial there, remember?

Add to this the 1/2 fuel option, and higher tech powered ships are now carrying twice their know jump ranges in fuel (making possible jump-in/ jump out capability). This however isn't fool proof. I note in MJD's writing that the Lucan Ship at 2nd Gateway made such vessels as set themselves under his control purge their jump tanks...
A- they couldn't jump away and flee, they had to "win or die"..
B- they avoided taking catastrophic fuel explosive hits from the Dominate's ships!

As I've come to hear it, it takes longer to find, shovel and process ice-teroids than do a GG refueling run.

And if you're the invader, timetables and speed are required.

If your the defender, you need to spot 'em and send the alarm, and slow the enemy down, or possibly give attritional damage.

Now a Vargr "horde" of corsairs isn't the same as say, the Dominate, or the old Zhodani Consulate Navy. There, you've got the "win or die" invading types, rapid strikes at pre-spotted weak (they believe) spots along the borders--yes those lines on the map that you can't see in space, or on the earth for that matter.

Of course, like hydrogen molecules which exist but I can't see with the naked eye, are there as well. I have faith in science they do, just as I know there are those lines that say "you have now reached 100d and its safe to jump-out".

Anyways..The most successful & largest bands tended to be the ones with organization, daring, and speed.

I don't see it as allowing real science suffer for story, but everyday, week we learn something new about space. Sooner or later, you'll miss something one of your gamers doesn't.

Its a good GM does his homework, no denial there Mal. In our online game, there are several of us who co-GM. Currently, I'm on vacation writing for Avenger Press, so I'm in player mode, and the Sci-Hard Co Gm is in the chair. We've a diverse group to please, and each of us in the "chair" has strengths and weaknesses. But the story needn't suffer either. You have to know your gamers, and plan accordingly.

The Greeks had it right when they said, "all things in moderation."

Been a productive day. Thanks!