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Sector, Subsector, Planetary navies

Ahoy there....
There are several canonical references to sector, subsector and planetary navies, but these are very skimpy and allusive (maybe excepting the fleet info in MT's Rebellion Handbook).
How do you handle these forces IYTU ?
Do they exist at all ?
What's the point of having them ? Cannon fodder ? Vital pieces of a layered defense strategy ? Essential part of the so-called "Island defence" strategy ?
Are they the imperial equivalent of a National Guard or a Navy reserve, with second-hand equipment or cast-offs from the "real" navy or are they fully operational forces, with state-of-the-art ships ?
How are ships procured ? On which budget ? The formulas in Trillion Credit Squadron could be used, but they sometimes give really wild results.
Command structure : who's the boss ? How do these navies interact with each other and higher" echelons, i.e. subsector, sector, imperial (imagine the logistical and C3I nightmares that could occur).
How are their personnel trained ? Imperial institutions? Their own ? Isn't this a bit of a waste of credits and energy ?

Etc, etc...
I'll dig out my Fifth Frontier War fleet counters and compare named planetary forces and numbered colonial fleets with the regular Imperial forces.

My understanding of the pre-MT naval structure is thet planets could build whatever ships they want and can afford. The sub-sector Duke could also raise a navy from local taxation. In peace time these forces would be deployed however the planetary authority or Duke decides respectively.
The regular IN forces, or sector Navy is deployed according to the whims of Admirals.

If disputes arise between worlds within the Imperium they may use their fleets against one another, provided they obey the rules of war and don't interfere too much with trade (a bit like a mega corp trade war). If they overstep the mark then the Duke may involve subsector forces to settle the dispute and/or call in IN forces in cases of real emergency.

In the event of war between stellar polities, such as the Frontier Wars, then the planetary and sub-sector forces become subordinate to the IN and are deployed as the "Admiralty" sees fit.

Note that some planetary Navies could have ships equal to or better than regular Naval ships, the majority are probably inferior though.
Depending on the shipyards within a sub-sector the sub-sector Navy could be on a par with the regulars, but probably not.
I did a study of this one. GM thought it was appropiate for my character. (Book-5 Naval officer, Grand Admiral (retired) Soc-15. Figured he was now a Duke responsible for a Subsector directly, GM picked Glisten because of all the border area Glisten is responsible for, with a secondary responsibility of advising the Sector Duke (Duke of Regina, later identified as Duke Norris) on matters of deployment of the Naval assets within the Spinward Marches and working closely with the Grand Admiral of the Marches for coordination of all Naval assets within the Spinward Marches. I did have to build the Glisten Subsector navy from the ground up and used TCS. We quickly found that while the Glisten subsector is fairly large (And the imperial worlds in Pax Rulin and District 268 which Glisten is responsible for)the majority of planets contribute very little to the budget but Glisten itself contributes quite a bit of money. I went for standardization so maintenance and construction would be easier. I also built the fleet with the proportion of 1 8 ship batron, 2 8 ship Cruron (Heavy Cruisers) 2 8 ship Cru-Ron (Light Cruiser) 20 8 ship Desrons, 40 8 ship Destroyer Escort (1000 ton) squadrons, 80 8 ship Corvette (400 ton)squadrons, tankers in the proportion of one per 2 Drednaughts and one per 4 cruisers (So refueling operations would have the capital ships no engaged in skimming ops.) 4 couriers per BatRon, and CruRon plus 6 per naval base and 4 per scout Base. (ANd extra couriers for systems I deemed important and communication hubs, not neccessiarly the same thing.
And I did build one Batron under the battlerider concept (So I had a 30KTon Monitor if I wanted to build it in quantity.) I was concerned about the cost of maintaing a fleet so I used two years of resources from Glisten alone for the subsector fleet (Used local resources to build local defenses like fighters and SDB's.) When I was finished I had 3 Batrons 6 Crurons (Heavy) 6 CruRons (Light) and all the smaller ships associated with those batrons in reserve, 1/26th of the ships scheduled for mainentance ant any time and still had enough capital ships left over that roving patrols (And if you keep them moving you can set up a patrol patern that will put your ships in position for mantainence when they are scheduled.) putting half a squadron of capital ships (4 Drednaughts or Cruisers with escorts and tankers) (with the other half in jump) at all but 4 systems the subsector was responsible for. I was generating more than enough income for maintenance and even had money left over to build extensive system defense ships and fighters. (I really began to feel sorry for Pirates.) With a fleet that size and looking at various sources for fleet designations etc, (the Rebellion Source book and FSOTSI when they came out later were quite useful) I came to the conclusion that Subsector and Sector fleets could be used for patrols, as guard ships, Piracy suppression and general defense while the IN would be primarily a reaction force and offensive weapon concentrated and centralized. Given the size of the Imperium, the nature of communications and the nature of combat operations under those assumptions You would need a very large force to accomplish worthwhile offensive operations. So the IN IMTU is kept at Squadron level or larger at important Nodal The Sector Navy is the Strategic reserve (Defensive operations initially but backing up the IN on offensive ops as needed.) And the Subsector Navy is routine day to day operations convoy escort, anti-piracy patrol, general defense and a tripwire to identify and pinpoint enemy offensive operations. This was based on Glisten, think about a highly populated subsector that isn't on the border of the Imperium, Mora's numbers are staggering as is most of the subsectors in the Solomani Rim. And that is a Naval budget of only Cr500 per head times the gov factors and times the tech diference (per TCS rules). (At Cr2 per head that makes a hell of an income for your subsector Duke.) Generally local training would be based on budget and experience, and command. Most of them would be drawn from the same sources as the IN and most of the others plus the Subsector and Sector Navies would also be able to draw from those that muster out of the IN. All in all in MTU the Subsector Navies integrate into the overall picture and like the US Reserve and National Guard integrate into the military fairly seamlessly.
Overall I think Bhoins is right, although I'd cut the size of those subsector forces, just to give the pirates a chance (I've got to have pirates to menace my PCs!). TCS gives players too much money to spend, anyway.

IMTU the planetary navies focus on system defense and customs patrol, along with piracy suppression. Almost all their ships are not jump-capable, even if the system is TL15. Most jump-capable ships owned by planetary navies are couriers. In some systems (Jewell, Rhylanor) the planetary navies own fleets of "SDBs" that are nothing less than Imperial Navy battleriders. Most systems are lucky to have a few squadrons of fighters and some 200/400 dton SDBs.

Subsector and sector fleets are the "colonial squadrons" shown in 5th Frontier War. They do not belong to the systems they're based in (which is the name on the FFW counter) but to the local Imperial government. They normally serve as the "tripwire" for the borders: making the patrols and keeping an eye on the enemy over the line. In war they form the first line of defense (and so are almost entirely formed from battleships, not battleriders/tenders) and serve to give the "Island systems" their mobile striking force for raids and counterattacks. Many of these ships are second-line Imperial Navy ships, but some are state-of-the-art ships that the Navy feels are better suited to the operational role of the "colonial" forces.

The Imperial Navy's role is the strategic reserve, for the offensive to restore the situation as the Empire wants it. They have the best ships (mostly battleriders in the BatRons) and stay concentrated deep behind the borders (the reinforcements in FFW coming from Corridor Sector are these ships, IMTU) where they spend their time rehearsing attack plans. These squadrons are intended to find and destroy enemy fleets and retake vital star systems.
Actually when you look at the way the budget is calculated Cr500 a head may seem like a bit much but it would make the US military budget during the late 80s approximately 106 billion. (250 million people X 500 X .85 (factor 4 government)) When you consider that the all volunteer force in the late 80s was in excess of 2 million people, if the average pay was 30K per year, (I think that is definitely low) the payroll alone is 60 billion. A single Aircraft Carrier (without airwing and escorts and support ships) is 4.5 billion to build. The original price tag of the B-1 bomber was approximately 1 billion dollars. During the late 80s there were 13 carriers in active US Naval service. Cost of a carrier is 4.5 billion. Cost of the airwing is an additional 2.5 billion. Cost of the rest of the battlegroup is 8-10 billion perhaps more. Maintenance of the carrier fleet according to TCS rules is 19.5 billion. Now add the support ships, the Marine amphibous groups. Additional escort ships. (The carrier groups only accounted for 117 out of the 700 ship navy.) 18 trident ballistic subs at 5 billion each, most escorts will come in under .5 billion. Attack subs run about 2 billion each though. Lets average the rest of the navy out at 1 billion each. (Probably low but what the heck.)That works out that the navy requires 85 billion to maintain the fleet. Don't build much more or replace anything.
I like to keep the size of the fleets small, especially in a TCS campaign, so that the players feel the losses more. To lose one capital ship out of 30 isn't so bad, but to lose one out of 8, now that's different.

Of course, in most TCS games, players tend not to build real TRAVELLER capital ships, but instead build the missile/meson rock combinations if they can, or just lots and lots of missile boats if they can't. Either one increases the numbers of ships by quite a lot.

I find myself wondering about other missions for the subsector/sector navies. Being as they're more familiar with their sectors (and presumably the enemy systems next door) would they tend to get a lot of the covert intelligence missions? What about control of traffic into/out of Imperial space?
Sigg basically hit it on the head, with respect to the Imperium. I have no clue how the other powers are structured, but the Imperium seems to be set up as almost a mirror of the Roman Empire, with the provincial forces functioning as an equivalent to the Roman militia and limitanei and the Imperial forces filling to role of the Legions.

As for the TCS budget rules, we now know that those were specially crafted for the Islands Subsector campaign and aren't supposed to be used for the Imperium as a whole (TCS budgets would result in an Imperial Navy several times larger than it is), though a friend and I were thinking that over and we thought the TCS rules would work just fine if one keeps construction times in mind, which serve to form a self-limiting factor in just how much yard tonnage is actually available for new construction after tonnage for ships in for repair/refit plus the tonnage held back for "emergencies" is taken into account.

As for the missions sector and subsector navies might perform outside of combat, I'd say it would depend heavily on the TL of the ships and the local conditions. The one problem with having local forces conducting intel ops is that I'd imagine the Imperium would want to keep that sort of thing limited to folks they know they can trust ;) Customs/anti-piracy patrols would definitely be a possibility, I'd think
IMTU, the Imperial Naval Budget contribution is split; half to the IN, 1/4 to the sector and 1/4 to the subsector fleets.

System fleets are not part of the "Assessment".

Now, system fleets proliferate, but are NOT for major actions. They include patrol craft of various sizes, system control platforms, and Space Rescue. Certain paranoid major worlds might keep a couple of cruisers They answer to the world's government (which may or may not include the planetary noble...).

The local noble may ALSO have some firepower, but then it's personally funded, either through investments, government contribution, Feif revenues, or as a budget share from several in-system planetary navies. It varies.

Subsector (and occasionally local multi-world member polity fleets) provide the anti-piracy patrols, generally operating things akin to Type T's... in a variety of variations on the them. Many try to stick to that hullform, tho, for recognition factor. They answer to the subsector duke.

Sector Fleets instead serve as a locally mobilizable adjunct to the IN Fleets. Mind you, these ARE the IN Reserve fleets, IMTU, so reserve fleets might not be where they are "on paper", due to the sector duke having had them show the flag, or collect recalcitrant subsector moot members, etc. They operate on a par with the IN, but limited to locally sustainable tech levels.
IMTU, defense spending goes backwards: the budget is based on the traffic through the ports, because I want MTU to reflect Travelling. Also, to me, worlds look more like provinces, and less like nations. The Imperium is the nation. The worlds have colonial forces, much like Texas has militia, reserves, the Rangers, what-have-you.

I use a quick-and-dirty point system to determine the traffic through a system's mainworld, then set the defensive budget equal to the volume running through that port in one week.

It's quick, it's cute, and it can be done more or less on the fly -- no precalculation necessary. Not too much in the way of rules, either, except for the traffic calculation... and that gets me two birds with one stone.

To find the traffic running through a world, I first figure its 'traffix index': I count up one point for an A/B starport, one point for In/Ag worlds, one point for Rich worlds, one point for TL A+, one point for being on the X-boat route, one point for capital worlds, one for high pop worlds, and so on. I also subtract one point for a D/E/X starport, one point for Poor worlds, etc.

Then I find the 'traffic index' of its most significant neighbor, where 'neighbor' means within 4 parsecs or so.

I then average these indices together (or if I'm feeling up to it, I take the square root of their product instead). This result is a traffic exponent, where a '1' is tens of passengers per week, '2' is hundreds of passengers per week, etc. Freight is something like ten times the number of passengers, in tons.

The defense budget, then, is in tons equal to the volume of freight passing through the port per week. Also, the value of these ships is appx MCr1 per ton. So a world with a 15,000 tons of freight passing through its port has 15,000 tons of system defense, at a price of 15 billion credits.

Example: Rhylanor
Rhylanor's UWP is A434934-F A Hi Cp. It's on the X-Boat route. Its trade index is 6.

It's best neighbor is Porozlo (A867A74-B Hi) with a trade index of 4. The average is 5, meaning around 100,000 passengers per week, and 1 million tons of freight per week.

Thus Rhylanor has 1 million tons of system defenses, with a price tag of one trillion credits.

Of course, worlds like Glisten and Rhylanor are likely to have significant Imperial Naval elements stationed there as well.
robject: not trying to be confrontational, but that makes each system sound MORE like a coutnry, and LESS like a province.
Is there an "official" system for determining the name/number of sector and subsector fleets. For example, if I wanted to work up the subsector fleet for Nightmare subsector in Ley sector. What would the fleet's number be?
in the spinward marches seventy percent of the population lives on just seven planets, and some subsectors have no significant class A shipyards. the subsector system is only a mapping convention and doesn't make sense as a political system. you can try ditching the subsector system altogether, and simply go with the major population centers.


"the imperium rules the space between the stars", i.e. the imperium rules the starports. imperial land grants to nobility are not just unrelated bits of land plopped anywhere, they are the starports, and the nobility runs the starports. all worlds relate to each other and to the imperium via these ports and these nobility. the imperium and the imperial navy and marines are supported by taxes on interplanetary commerce while nobles get to keep a portion of the taxes they collect. noble tax rates, rank and social standing, and political power in the local moots, are all determined by the tech levels of their worlds and by contributions to the imperial navy and marines made by their starports and shipyards. rank structure consists of baron (non-industrial world), vice-count (industrial world), count (jump-capable world; the count's county extends to the limit of that jump capability), marquis (world makes capital ship contributions to the imperial navy), and grand marquis (march contains other marquis'). each increase in rank results in an increase in tax rates and voting power in the local moot alloted to that noble.

the emperor and the imperial nobility are also supported directly by their own tax rates on interstellar trade. a duke is a member of the emperor's family or is a trusted counselor appointed directly from the imperial court. he runs a sector and is responsible for its defense, for the enforcement of imperial law, for the encouragement of interstellar trade, and for keeping starport nobles in line. he directly and by delegation controls all imperial assets in a sector.

a count+ is responsible for the defense and policing of his county/march. he may be assigned the defence of other areas as well, in which case they are considered to be part of his tax base also. thus, there are no "subsector fleets", there are county and march fleets - if the local duke allows any such fleets at all. presumably he would, especially for exposed locations such as glisten and efate, but these would never be allowed to grow to any size sufficient to challenge the main imperial fleets.


this approach explains and puts on a better footing quite a bit of cannon.
Actually yes there is. The MegaTraveller Sourcebook has the Imperial Numbered fleets laid out, by subsector for each subsector on the eve of the Rebellion. (Circa 1116) Though it doesn't say what each numbered fleet consists of. Fleets aren't going to mave around much, except in time of war. Elements may be transferred about, they may be on patrol, but they will still have the same home ports. (IE the Atlantic Fleet is based out of Norfolk, VA)

Originally posted by Paraquat Johnson:
Is there an "official" system for determining the name/number of sector and subsector fleets. For example, if I wanted to work up the subsector fleet for Nightmare subsector in Ley sector. What would the fleet's number be?
Aramis replied "robject: not trying to be confrontational, but that makes each system sound MORE like a coutnry, and LESS like a province."

Or maybe more like a business...? ;)
Much of this has been covered, but I thought I'd deposit my two cents:

Originally posted by Thierry Maitrejean:
Ahoy there....
There are several canonical references to sector, subsector and planetary navies, but these are very skimpy and allusive (maybe excepting the fleet info in MT's Rebellion Handbook).
How do you handle these forces IYTU ?
Do they exist at all ?
The have been mentioned ever since Book 5 / High Guard as an implicit part of the generation process, so obviously they do exist.

What's the point of having them ? Cannon fodder ? Vital pieces of a layered defense strategy ? Essential part of the so-called "Island defence" strategy ?
I think their organization would vary widely. The thing to keep in mind here is that the Imperium is a feudal state of sorts. Though many aspects of it strongly resemble US/USSR "strong military raised through taxes" model, the power distribution is more disparate. There may be some strategic thought into how naval power is accorded, but it's more a political necessity in the fuedal structure.

The biggest and best ships, of course, would be the product of the industries of multiple worlds. This means that aside from having the biggest budget, the Imperial Navy is also in the best position to make massive ships efficiently. Some subsectors might have a few impressive industrial centers, but still would rely largely on trade for other sectors to get more materials.

What this probably means is that even if the subsector can build their own ships, they are probably getting many components from the imperial navy or designed for the imperial navy, just to take advantage of the industry norms. This gives the Imperial Navy and the Emperor a lot of leeway to control what kind of power ends up in the hands of the dukes. And they probably like it that way.

Even then, only very wealthy and industrialized subsectors would have the means to build their own ships. Most probably get stripped down navy surplus ships.

The situation is even more scattershot for planetary navies. Smaller worlds with less industrialization would have to rely on subsector navies or purchases from other worlds. Large, industrial worlds are far more likely to have huge fleets of monitors, asteroid ships, and SDB's, many probably not jump capable.

Are they the imperial equivalent of a National Guard or a Navy reserve, with second-hand equipment or cast-offs from the "real" navy or are they fully operational forces, with state-of-the-art ships ?
That's not a bad anology, if you keep in mind again this is a feudal empire. Someone brought up Rome as a good example.

Various books have presented personal forces of nobles in power; their may be some conventions, but their composition and organization would probably vary widely. In the Spinward Marches campaign, the "Dukes Huscarles" are presented. In Domain of Gateway, the Imperial Trade Cluster Authority covers the area of the sector capital and helps compensate for losses of the Imperial Naval ships in the region to the Solomani Rim War effort.
Originally posted by Paraquat Johnson:
Is there an "official" system for determining the name/number of sector and subsector fleets. For example, if I wanted to work up the subsector fleet for Nightmare subsector in Ley sector. What would the fleet's number be?
MT Rebelion Soucebook has a complete listing.on page 26.
it's available at drivethroughrpg.com as a PDF, under $12

IMTU, the IN organises the Sector into nominally 16-20 numbered fleets. The reserve fleets can purchase surplus IN equipment at scrap rates, fully intact, provided they keep it in service. But the Reserve fleets operate on a budget provided by the Sector Duke. There is a reserve fleet for every numbered fleet, even if it ammounts to just a few Type T's and Gazelles. (District 268, anyone?)

TYpically, a Reserve fleet will be comparable in nominal strength, but available strength will usually be less, to a regular IN Fleet, but the sector navy (reserve fleets) will look almost identical to the IN; personell are kept trained to a full IN level, and the equipment, while often old, is very much still high-end.
According to GURPS Ground Forces, there are three levels in the imperial army:

1) local defence forces, under direct command of the local governement, with no direct ties to the Imperium, their size is based on TL and population of the world, and they've got reserve, 10% of the active units are able to move off-world.

2) sub-sector unified armies, under command of the sub-sector highest ranking noble, their size is about 10% of the sum of all the active units of all the sector's local defense forces, all units are able to move off-world.

3) sector commands, under command of the sector highest ranking noble, they are basicaly ghost armies with only HQs and a squeleton cadre, in wartime all sub-sector armies of a sector would act under a single command rather than individually.

With this in mind we could figure out that planetary, sub-sector, and sector navies are organized like this:

1) planetary navies, whose size depends on TL, size and starport rating (the starport rating being a measure of a world opening to the outside, in should influence the size of it's navy), depending on the world attitude they could be real combat oriented navies, but they're more likely to be so kind of coast guard, concerned more with policing the space lanesand fighting piracy and contraband, they would be equiped for 90% of the tonnage with SDBs, cutters and other non-jump capable ships, and for 10% of jump-capable ship (mostly courriers and maybe some light combat ship suited for chasing pirates like the class T cruiser), exact type and TL of ships depends of what the world is able and willing to buy.

2) sub-sector navies would have about 10% of the dTon avaible to all of their world's planetary navies, but all of it jump-capable, those ships being combat ships, some of them state of the art, some of them older, surplus of the IN designs, depending of the sub-sector, forming the backbone of the imperial defense

3) sector navies would have very few ships (most of them C3, support, recee and courriers) as their only role in peace time would be planning of potential crisis, they would only become active in wartime and act as unified command for all the units of the sector's sub-sector navies.

According to that picture the IN would have to main tasks: conducting all action outside the imperium (both peacetime courtesy visits and wartime raids) and acting as a strategic reserve able to bear its firepower where needed in short notice.

Well, that's only a theory, but it seems quite logical to me that fleet and ground forces should have the same kind of power levels.