Ship building industry of the Third Imperium

[Hal]

Hello Folks,
I got to thinking (I know, always a bad sign!) about the ship building capacity of the Third Imperium.

The laws of economics being what they are, industries that can not make use of their work force through sales of a service or product, eventually go bankrupt from lack of income versus a large outflow of expenses. For example? Lets say that we have a need within a region, for 100 widgets per year. Furthermore, we have 10 companies who would like to manufacture widgets. If each company manufactures 10 widgets apiece, they will stay in business as they provide what the market needs. However, if 9 companies produce 10 widgets apiece, and the 10th company produces 30 widgets - we have a glut in the market with 120 widgets. 20 units do not get sold (as the market can only use 100). Either some of the companies take a loss on producing those extra 20 units, or they have to cut back on production costs and volume of production. If one company however, has found a way to make 100 widgets, and is content with only a 1% profit margin - all those other 9 companies will soon be put out of work - especially if their costs in producing that widget requires that their product be priced at 10% higher than that one company's costs.

Granted, I'm simplifying things greatly, as cost of labor, cost of materials, overhead costs, etc - all factor in for what the "widget" will be worth versus what it is sold for, but you get the gist of my point.

My point is - has anyone bothered to compute the overall Ship Yard capacity per world, and then looked at what the demand for such shipyard services will be?

Lets take Strouden in the Lunion Subsector as an example. Using the Trillion Credit Squadron rules for determining shipyard capacity (the only place that gives rules for calculating that in the CT universe by the by!), we find that Strouden has a grand total of 9.9 MILLION dtons worth of production capacity per week!

That my friends, is a LOT of production capacity. Now, lets examine this in the light of the rules as given in the CT rules. In Traveller, a ship is required to spend 2 weeks in a shipyard undergoing maintenance. One could presume, that a 200 dton ship undergoing maintenance would require 200 dtons of shipyard capacity for two weeks - requiring the work of the shipyard crew to complete the maintenance required. Under the rules, it takes 48 weeks for the shipyard crew to manufacture a 200 dton hull utilizing 200 dtons worth of shipyard capacity. Maintenance is but 2 weeks, so maintenance versus actual construction time is approximately 2/48ths or 1/24th the time required to build a hull from scratch. Does this make sense overall? Maybe - maybe not, I'm not an expert on ship building

In any event, maintenance requires roughly 4% of the time required to build the ship from scratch, so that seems reasonable of sorts.

But this brings me to my next point. Shipyards will have the following services and/or products to offer to their customers:

Annual maintenance of the ship/vessel
Unexpected repairs due to accidental damage or acts of violence
Unexpected repairs due to faulty parts or normal wear and tear
Refurbishing ships that are growing old
Upgrading ships with newer equipment
Building new ships
(possibly) breaking/salving old retired hulls

How much tonnage capacity does the Third Imperium require to accomplish all of those services?

If you consider that each maintenance project requires 2 weeks, a shipyard that devotes say, 200 dtons of capacity towards maintenance, can service 25 x 200 or 5,000 dtons of merchant shipping in a year (assuming 2 weeks off for vacation of shipyard workers and/or maintenance on shipyard facilities).

I guess the question becomes one of "Just how many shipyards does the imperium really need, and just how much of those services/products can be supplied by heavily populated worlds?

9.9 MILLION dtons of capacity can provide maintenance services for:

1,225 Plankwells per year

or

475 Tigress class Dreadnaughts per year

or

49,500 Destroyers


That's just from ONE planet using the rules presented in TRILLION CREDIT SQUADRON. I would presume that the Imperium doesn't really utilize ALL of that shipyard capacity that TCS implies it has!

 

[flykiller]

... we find that Strouden has a grand total of 9.9 MILLION dtons worth of production capacity per week!

note that that is dton _capacity_, not production. if a 20kdton ship takes two years to build then that means 20kdtons of capacity is occluded for two years. also, maintenance work occludes construction work, so the more ships that are built, the less construction capacity a shipyard has. also, imtu a 9 world has a capacity of 1mdtons (industrial 1.2) and an A world 10mdtons (industrial 12). all this taken together brings production down to manageable levels.

a short research session shows that ship production on modern earth is double that specified in TCS - so the TCS rules are reasonable, since one may expect starships to be more complex and require more effort to build than simple seagoing container ships.

 

[samuelvss]

Also, capacity includes surge capacity, and lingering capacity. Funding gets cut in the middle of a project, immediately scapping the hull or immediately storing elsewhere may not be the most economical answer. Market fluctuations, the stop and go nature of large contracts, would demand that excess capacity be available, except at the most in-demand builders, where they can afford to trun business away.

Labor and equipment is easier to marshal than extra yard space; equipment can be stored, and labor layed off, but the yard space will be held.

There are size and space efficiency problems, too. The number of 200 ton spaces will likely not match the number of 200 ton hulls; or, indeed, a 100 ton hull may take the same space as a 200 ton hull. Geometry does not come into the tonnage equations, but it is a real world factor. The 400 ton Patrol cruiser might commonly take up a 1000 ton or 2000 ton bay. Operations tend to expand into the space available, rather than constraining themselves to the space required.

Airlines have extra planes, crews, etc. They need to to meet holiday surges and market upturns. Managing this extra capacity will of course be a challenge, one of the challenges that separates the 10% of businesses that make it from the 90% that don't.

Another factor is that shipyard capacity is a strategic asset. Wise strategic actors will keep strategic assets in reserve, and pay private enterprise to do it. Subsidies may account of usually empty shipyard capacity in strategically advantageous areas.

I think a relevant question is "How much capacity is used on the average?"
Is the capacity off? I dunno!

I think there are a lot of variables in the equation, though, that dictate that a significant excess capacity is certainly rational.

 

[Captain Midnight]

One could presume, that a 200 dton ship undergoing maintenance would require 200 dtons of shipyard capacity for two weeks - requiring the work of the shipyard crew to complete the maintenance required.

The implication from TCS pp. 33-35 is that only ships requiring refitting, repair, or construction require the services of a shipyard. This is also how it works in GT: Starports, with some additional wrinkles. A lot will depend on just how extensive you think the annual maintenance actually is... but I'll point out that it's generally considered possible to perform it in the field, albeit with more difficulty, which would argue against all the bells and whistles of a shipyard being an absolute requirement.

 

[Hal]

The implication from TCS pp. 33-35 is that only ships requiring refitting, repair, or construction require the services of a shipyard. This is also how it works in GT: Starports, with some additional wrinkles. A lot will depend on just how extensive you think the annual maintenance actually is... but I'll point out that it's generally considered possible to perform it in the field, albeit with more difficulty, which would argue against all the bells and whistles of a shipyard being an absolute requirement.

Actually, you make my argument for me

The logic is as follows in GURPS STARSHIPS (I thought I saw a JTAS reference in the CT reprints, but I can't find it off the bat darn it!)

Class A starport: 2 weeks
Class B starport: 2 weeks
Class C starport: 4 weeks
Class D starport: 8 weeks
Class E starport: 8 weeks

Class E starports are basically, nothing more than a cleared level area for the starship, implying that without the special tools, stockpiled parts etc - the annual maintenance would require 8 weeks.

Ditto with the class D starport.

Class C starports on the other hand, have repair facilities available for which makes it a C starport instead of a D or E. Apparently, repair facilities on hand, make the whole process take 1/2 the listed 8 weeks time.

Now, the ONLY thing that differences a class C starport from a class A or B starport, is that the class A and B starports have the ability to build ships/boats. As this is a function of the shipyard itself, and the fact that class A and B starports can conclude the business of annual maintenance in 1/4 the time (ie 2 weeks), the question now becomes one of...

Is it implied that the shipyards are engaging in routine "annual maintenance" in order to reduce the required time for the ship's annual maintenance? To me, the answer is yes.

My question as posed thus far is "what does Strouden need 9.9 million dtons worth of capacity for? If for example, Strouden wanted to manufacture a 20,000 dton hull that is not a prototype hull, it must allocate 20,000 dtons worth of shipyard capacity for a total of 139.2 weeks. Were it to allocate 40,000 dtons worth of shipyard capacity to the ship's construction, it would take a mere 99.43 weeks to complete. The point is, the shipyard capacity is essentially currency by which ships are built at any given shipyard.

So what activities are conducted at a shipyard? So far, the only written activities are starship construction, starship repairs, and starship refits. Problem is - why are Class A and/or B starports required for Annual maintenance if not for the presense of their shipyards?

 

[Magnus von Thornwood]

How about TLs?

In all this talk about capacity and such I see no mention of the Tech Level of the shipyards. Surely that would also have some bearing on what can be built/repaired by said yard, not just it's capacity and rating?

Just wondering.

 

[savage]

Economics

Just a couple points;
1. economic focus of the culture. Is the society building ships or something else. We have the ability in our society to build more satellites and space craft than we do.
2. Industries usually don't like being at full market saturation. It raises the risk levels for getting funding, pain in downturns, etc.

During ww2 we produced a ship per day in the US. War time capacity is a focused direction.

 

[flykiller]

During ww2 we produced a ship per day in the US.

yes, and the entire country was on ration cards for food and gasoline, tires and coats were almost impossible to get, and everyone participated in scrap metal drives. not something you want to do in peace time.

I see no mention of the Tech Level of the shipyards. Surely that would also have some bearing on what can be built/repaired by said yard ....

yes, and no. the spinward marches has only four yards capable of doing tech 15 work - mora, trin, rhylanor, and glisten. imtu they are fully occupied building and maintaining the imerial fleet. if they have time and space they do side jobs for important nobles, not just any free trader that stumbles in. in other words since higher tech is in demand each yard is fully occupied at its level already. if that's what you mean.

A lot will depend on just how extensive you think the annual maintenance actually is... but I'll point out that it's generally considered possible to perform it in the field, albeit with more difficulty, which would argue against all the bells and whistles of a shipyard being an absolute requirement.

imtu field maintenance does not create shipyard capacity, it draws from it, i.e. every repair ship in the fleet deducts from shipyard capacity - both in displaced personnel and in building and maintaining the fleet support ship and its accompanying supply ships, a double or triple deduction. the big reason for field maintenance is to save recall transit time, i.e. a battle cruiser doesn't have to transit from jewell to rhylanor and back just for its two week maintenance.

 

[Magnus von Thornwood]

So flykiller...

How long I wonder before one of those four yards gets sued for refusing service to a free trader and it's lost or damaged because the only place they could get service refused them? I mean supposing that the ship survives to make a complaint. Hell, I'd make a complaint right there to the local MOJ office. On the grounds that the shipyard is now endangering my ship, crew and passengers. Hell, if I was real lucky some of my regular patrons both passengers and for sure freight shippers might to get on board. Nothing like a good class action suit. :smirk:

Oh and in point of fact the IN doesn't have all that many TL F starship in it's inventory, because there are so few TL F ship yards, most are TL C and D.

 

[aramis]

1) it's unlikely that the OTU would allow such suits
2) MoJ is likely to see the master's ticket revoked for allowing that level of disrepair
3) There is no evidence to support the 3I as a place of Rule of Law, and several places that make it explicit is isn't.

 

[Magnus von Thornwood]

Really now?

1) it's unlikely that the OTU would allow such suits
2) MoJ is likely to see the master's ticket revoked for allowing that level of disrepair
3) There is no evidence to support the 3I as a place of Rule of Law, and several places that make it explicit is isn't.

1. Why not, it's a valid claim.
2. Why is the master being punished for trying to get their TL F starship repaired at the only places where such repairs can in fact be done? It's not like a TL C yard can do the work, they don't have the tools or parts.
3. Then why have laws? I mean it sure seems to have them when convenient. Like those pesky Laws about interfering in the safety of the space lanes, you know like say the ones that say piracy is unlawful. It seems to me that this is one of those times when they might want to have the law enforced as the yard refusing to service a starship that can only be repaired at that level of yard would in fact have an impact on the safety of the Citizens and upon the holy Commerce.

EDIT: Note that the suit is not against the Imperium, which of course like any government has the right to not be sued if it choses (which I do think is sorta bogus even though I do understand why they do it), this is a suit against a private ship yard.

 

[robject]

Regarding shipbuilding capacity in the Marches... someone on the TML ran the numbers a decade ago. Maybe in 1996 or 1997. Anyone have that on hand? Am I going to have to grep for it myself?

 

[aramis]

1. Why not, it's a valid claim.
2. Why is the master being punished for trying to get their TL F starship repaired at the only places where such repairs can in fact be done? It's not like a TL C yard can do the work, they don't have the tools or parts.
3. Then why have laws? I mean it sure seems to have them when convenient. Like those pesky Laws about interfering in the safety of the space lanes, you know like say the ones that say piracy is unlawful. It seems to me that this is one of those times when they might want to have the law enforced as the yard refusing to service a starship that can only be repaired at that level of yard would in fact have an impact on the safety of the Citizens and upon the holy Commerce.

EDIT: Note that the suit is not against the Imperium, which of course like any government has the right to not be sued if it choses (which I do think is sorta bogus even though I do understand why they do it), this is a suit against a private ship yard.

It's only a valid claim if it's acceptable to the responsible parties for adjudicating it. In modern maritime practice, the captain is the final responsible party; if he can't get maintenance where he's at, he HAS to go where he can get it.

Further, buying a TL F ship in a region with very few TL F ports, one had better be willing to schedule for AND MEET the scheduling requirements; if not, again, it's a "Owner stupidity".

If you don't understand the concept of "Rule by men, not by laws", I don't know how to make it intelligible. But I'll try. Laws are a tool. In medieval society, laws were codifications of the lawmaker's will; the local authority had to interpret both the offense and the best course of action, the law being a guide, not a hard and fast rule to be followed.

Even in modern US law, we have a concept of Rule by Men, not by Law. One needs more than simple establishment of the facts; one must convince 12 men of not just the fact, but also the criminality, of the act. In a less "law based" society, its the belief of the judge that matters most.

Further, you're treating yard access as a right, not a privilege. No one but the 3I and the world gov't itself has a "Right" to access the yards, unless that world grants such; even still, such right is subordinate to the Imperium.

Further, the idea that the imperium grants many rights is doubtful. We know that the Imperium considers slavery and murder to be crimes of an imperial nature, along with piracy, barratry, and such.

The Imperium doesn't even codify the rules of Warfare... why would they codify access rights?

 

[coliver988]

Spinward Marches Ship Building Capacity

I thought Rob's site (http://eaglestone.pocketempires.com/) had something like that in the starport section, but he cleaned up a while ago, if I recall, and not all the links are there.

I thought there was something in GURPS Starports or Far Trader that indicated building volume, but I can't find that after a quick glance. Trillion Credit Squadron may have something in it.

 

[Magnus von Thornwood]

Umm...

OK, I have to admit to being a smidge snotty about the "why even have laws" comment.

I'll take your points vis a vis yard access, I guess MTU is more a society of Rule of Law, since I personally have such a bias.

Now as for Laws on murder, slavery, piracy and warfare I do believe it might actually have them but I would have to get into the stacks and do scads of research. But I do seem to remember such, in fact the use of WMD comes to mind as being part of the Code.

And what about a starship that was victim to pirates or some such and now needs maintenance to run? Or is the owner/master just hosed and out of luck?

(Odd little note, it's seems that my spell checker doesn't know the word Starship...how sad. Now it does! )

 

[robject]

I thought Rob's site (http://eaglestone.pocketempires.com/) had something like that in the starport section, but he cleaned up a while ago, if I recall, and not all the links are there.

I thought there was something in GURPS Starports or Far Trader that indicated building volume, but I can't find that after a quick glance. Trillion Credit Squadron may have something in it.

I think you're thinking of traffic info, rather than sheer construction. Anyhow, I back-engineered that based on what I thought the Imperium's traffic was like (but twiddled it so it would work for those who prefer a busy Imperium too).

Ah, here we go (blows electronic dust off of old files). October 1997, from our own Hans. This is just raw build numbers, but:

Date: Thu, 2 Oct 1997 15:03:44 +0200 (METDST)
From: Hans Rancke-Madsen <rancke@diku.dk>
Subject: Re: Industrial capacity

Douglas <douglas@teleport.com> writes:

Of course, the method I would use for calculating the population of planets
in the Spinward Marches would be to look up the figures in the listings. 
And then I'd pretty much ignore everything but the high-population worlds
except for establishing whether a world can defend itself against piracy.
  
>Assumption - Shipyard capacity = 1 ton per 1,000 pop. per week

I reccommend using tons per year as the measure and then divide all
maintenance by 50 (or perhaps 45 to allow for a 10% messup in scheduling
of maintenance).
 
Spinward Marches 
 
TL 9 shipyard capacity

 	1 shipyard with 30 Mt/year (Junidy)
	1 boatyard with  2 Mt/year (Aki)

TL A shipyard capacity

 	1 shipyard with  8 MT/year (Vilis)
	1 shipyard with 20 Mt/year (Narsil)*

TL B shipyard capacity

 	1 shipyard with 20 Mt/year (Porozlo)
	1 shipyard with 10 Mt/year (Mire)
	1 shipyard with  6 Mt/year (Gram)*
	1 boatyard with  8 Mt/year (Sacnoth)*

TL C shipyard capacity

 	1 shipyard with  6 Mt/year (Jewell)
	1 shipyard with 20 Mt/year (Fornice)
 
TL D shipyard capacity 

 	1 shipyard with  8 Mt/year (Chronor)*
 	1 shipyard with  8 Mt/year (Efate)
	1 shipyard with  8 Mt/year (Lunion)
	1 shipyard with  9 Mt/year (Strouden)

TL E shipyard capacity

	1 shipyard with  3 Mt/year (Pallique)

 
TL F shipyard capacity

 	1 shipyard with  8 Mt/year (Rhylanor)
	1 shipyard with 10 Mt/year (Mora)
	1 shipyard with  8 Mt/year (Glisten)
	1 shipyard with 10 Mt/year (Trin)

TL G shipyard capacity

 	1 shipyard with 2 Mt/year (Darrian)*
 
Of course, Darrian doesn't become functionally TL G until some time after
the Rebellion, but since we're only concerned with Imperial planets at 
the moment, it dosen't matter.

Total shipyard (Class A) capacity is 158,000,000+ tons per year (Note that
statistically speaking it is propably about 6 Mt more than that, but that
I can't prove). 70,000,000 of that capacity is TL B-, but then, if I was
buying the Imperial navy I'd find ways to get around that.

>Now, starting with the figures given above, who wants to figure out how
>much of this shipbuilding capacity is used by the Imperial fleets based in
>and around the Spinward Marches?  (I'm not!!)

Well, assuming the Imperial part of the 872 billion inhabitants you mention
above is 10/16th (roughly 10 subsectors are Imperial), the Imperial 
population is 545 billion. Naval taxes would be 272,500,000 MCr. Cut that
down by roughly a 3rd to reflect that some of the worlds that pay but don't
build have credits worth less than the worlds that both build and pay (If
you want more exact figures you'll have to provide them yourself). That
gives a budget of about 180,000,000 MCr. That gives you a fleet worth
1,800 trillion credits. This includes planetary, reserve, and regular
fleets. If you use that to buy system defenses (at MCr0.85 per T) you get
about 2,117 million tons of ship. If you use them to buy jump-6 ships
(not possible, of course) you'd get about 3,600 million tons. An
average of that would be 2858,t million tons. Let's say 3,000 million
tons for convenience.

Shipyard utilization:
	New construction: 2.5% of 3,000 million tons = 75 million tons.
	Maintenance: 3,000 million tons/45 =           67 million tons

Total 142 million tons out of 158 million tons, leaving 16 million
tons unaccounted for. That's about 10% off and in the right direction.
Seems to dovetail quite nicely.


      Hans Rancke
University of Copenhagen
     rancke@diku.dk
- ------------
        "The referee should determine the nature of subsequent
         events based on the individual situation."
                                _76 Patrons_, p. 8

 

[aramis]

And what about a starship that was victim to pirates or some such and now needs maintenance to run? Or is the owner/master just hosed and out of luck?

IMTU, he's likely to hve a several month wait. The TLF yards reserve maintenance bays up to 4 years in advance... Major shippers will build their own yard bays and lease them to the yard for 30-50% time share. IMTU, Regina has private yards; using WBH, players of mine built their own yard sections. Not cheap, either. Couple hundred million. But it paid off in a few years.

Getting repairs is always Space Available. If the space isn't available, you wait, or move on.

 

[robject]

Just for the sake of adding fuel to the general fire regarding capacity as it impacts traffic, here's the definitive post made by Derek, back in Feb 1996. I don't agree with his basis, but it's a good post anyway:

Date: Fri, 9 Feb 96 09:37:31 -0500
From: Derek Wildstar <wildstar@qrc.com>
To: xboat@MPGN.COM
Subject: Re: Trade and Commerce (XBd#527)
Message-ID: <9602091437.AA16315@qrc.com>

Andrew Madden <amadden@pcug.org.au> wrote:
> Recently, I was trying to get a feel for the sort of volume of trade and
> shipping which goes on in a place like the Marches.  [SNIP]

About three years ago, I did a similar analysis, covering the entire
Imperium.
From my work (which used quite different assumptions and methods to reach
the same kind of conclusion), I found that the average Imperial Class A
starport has 29 Billion tons of starship traffic a year, which works
out to 280 Million tons of goods and materials moved per week (on the
assumption that about 50% of the average starship is cargo).

Here's the entire analysis, reposted from a 1992-era TML posting:

Method:
I loaded the "new" rebellion-era statistics for all of the sectors for
which computer data files were available into a database and tabulated
the results.  The following analysis is based on worlds coded for Imperial
or Imperial factions, and should be accurate for the last years of the
Imperium or the beginning of the Rebellion.

The Gross Planetary Product and Taxation rules from Striker were used to
compute the GPP in Local Credits.  The Striker exchange table was used to
convert these to Imperial Standard (Port-A, TL-15) Credits, which were
then taxed at the suggested rates.  Rules from Trillion Credit Squadron
were used to compute the shipyard capacity of each Class A and B Starport.
The Trillion Credit Squadron construction rules were also used to estimate
the number and size of ships.

Summary:
The Third Imperium is a trade protectorate encompassing 10,497 systems
with a total population of about 16,731,817,153,000 sophonts.  The annual 
Gross Imperial Product is 219,474,958,700,000,000 Credits.  This is the 
total value of all of the goods and services produced on all the member 
worlds of the Imperium in one year, adjusted to Imperial Standard Credits.
The Imperium imposes a tax burden of about 1% of the GIP, producing Imperial 
revenues of about 2,194,749,587,000,000 Imperial Standard Credits per year.

The shipyards of the Imperium's Class A starports have an aggregate capacity
(all tech levels) of 5,098,672,838 displacement tons for vessel construction.
Its Class B ports have an additional capacity 4,367,049,593 displacement tons
for the repair and annual maintainance of starships.  The table below shows
the tech level breakdown for the Imperium's Class A and B starports.

----------------------------------------------------------------
TL  ClassA  ClassB      BuildTons      MaintTons  Build%  Maint%
----------------------------------------------------------------
4        0       3              0        117,600    0.00    0.00
5        0       8              0      1,055,652    0.00    0.02
6        2      43         82,000      4,944,480    0.00    0.11
7        4      89      3,763,899     10,738,080    0.07    0.25
8       23     196     15,853,016     40,124,708    0.31    0.92
9       56     308     11,689,867    104,965,363    0.23    2.40
A      135     427     26,558,910    137,957,429    0.52    3.16
B      158     518     87,529,595    420,700,561    1.72    9.63
C      238     579    300,827,072    671,936,269    5.90   15.39
D      244     484    540,769,684    525,260,647   10.61   12.03
E      388     455  1,254,523,697    857,493,892   24.60   19.64
F      485     251  2,163,360,932  1,271,804,383   42.43   29.12
G       55      21    693,714,164    319,950,528   13.61    7.33
----------------------------------------------------------------
ALL  1,788   3,382  5,098,672,838  4,367,049,593  100.00  100.00

Shipping Volume:
These figures can be used to estimate the approximate volume of shipping
within the Imperium.  A 10,000 displacement ton hull will be used as an
"average" to estimate construction times.  A hull occupies its tonnage
in the shipyard for its entire construction time of 160 weeks.  Ships
must also undergo annual maintainance; 4 weeks every year.  The yards of
the Imperium have an annual capacity of 265,130,980,000 ton-weeks of new 
construction or maintainance, and 227,086,570,000 ton-weeks of maintainance
only.  Presumably, the Naval Bases, Naval Depots, Scout Bases, and Scout
Waystations contain additional ship construction and repair facilities
to build and maintain ships for the Imperial military services (this is
a logical extension of the policy that a world's survey data does not
include the personnel or technology of any military bases present).

Peacetime shipyards and ships presumably exist in an equilibrum, the
number of new ships constructed is the same as the number retired from
service; and all ships in service can recieve their annual maintainance.
In practice, there is always some spare shipyard capacity to provide for
regional differences, trade expansion, and so on.  Let us assume this
spare capacity at 10%. 

Let us assume that the active lifetime of a ship is 80 years (exactly twice the pay-off time).

Computation:
X = total tonnage in service
X/80 = annual tonnage taken out of service = annual new construction
160*(X/80) = 2*X = shipyard capacity in ton-weeks for new construction
2*X <= 0.90 * 265,130,980,000 (available new construction capacity)
4*X = shipyard capacity in ton-weeks required for annual maintainance
6*X = 0.90 * (265,130,980,000 + 227,086,570,000)
X = 73,832,634,000 displacement tons.

General Formula:
T = New Ship Construction Time in Weeks
L = Lifetime of Ship, in Years
U = Shipyard Utilization Factor
N = Ton-Weeks of Shipyard Capacity for New Construction
M = Ton-Weeks of Shipyard Capacity for Maintainance
X = Aggregate Tonnage of In-Service Shipping

Therefore:
X = (U * (N+M)) / (4 + T/L)

But:
X <= (U*N) / (T/L)

Interestingly enough, a 5,000 ton ship requires only 144 weeks to complete.
Therefore, 11 5,000 ton ships can be constructed for slightly less shipyard 
capacity as 5 10,000 ton ships.  From a construction point of view, smaller 
ships are more efficient than larger ones.  However, when carrying cargo or 
passengers, larger ships tend to be more efficient. A balance must be 
struck, and 10,000 tons was chosen rather arbitrarily.  The table below
presents a mix of ship sizes; the ratio column indicates how many ships of
a given size can be constructed using the same amount of shipyard ton-weeks.
For the purposes of estimating the number of ships, I will assume (again
rather arbitrarily) that a mixture of ships will be built so that every
10,000 tons of shipping represents an average of 1.6 ships; the Number
column shows how the shipping is distributed to get this total.

----------------------------------
     Hull  Weeks     Ratio  Number
----------------------------------
      100     40  400.0000       2
      200     48  166.6667       4
      400     64   62.5000       3
      800    112   17.8571       4
    1,000    120   13.3333       6
    5,000    144    2.2222       2
   10,000    160    1.0000       8
   20,000    174    0.4598       2
   50,000    192    0.1667       1
  100,000    208    0.0769       0
  200,000    224    0.0357       0
  500,000    232    0.0138       0
1,000,000    240    0.0067       0
----------------------------------

Trade Volume:
Presumably, Class A starports are also primary trade and commerce locations, 
so that most traffic passes through them.  Class B ports would be 
responsible for less of the trade, and so on down through Class E (slim) 
and X (none).  The following table presents a possible breakdown.  The
ships column indicates the number of arrivals and departures (flight
operations) per week; less than half this number will be in port at any
one time.

------------------------------------------------------------------
Class  Number  %Trade  TonsTrade       TonsEach    Ships  1Every
------------------------------------------------------------------
A       1,788   40.00  29,533,053,000  16,517,368  2,643   3.8 Min
B       3,382   32.00  23,626,443,000   6,985,938  1,118   9.0 Min
C       2,768   19.00  14,028,200,000   5,067,992    811  12.4 Min
D       1,079    7.00   5,168,284,448   4,789,884    766  13.2 Min
E       1,252    2.00   1,476,652,699   1,179,435    189  53.3 Min
X         228    0.00               0           0      0       N/A
------------------------------------------------------------------
ALL    10,497  100.00  73,832,634,000         11,813,221

It is interesting to note that there are 11,813,221 starships registered
in the Imperium; approximately 1,125 for every world.  The frequency of
flight operations at a Class A port is about as hectic as the busiest of
present-day airports.  For a commercial starship, between 40% and 60% of
the ship's volume will be cargo or passengers; therefore a Class A starport
handles about 8.25 million tons of cargo a week.  This is quite a large
volume of trade, but not enough to feed a planet of billions.


wildstar@qrc.com
------------------------------------------------------------------------------
                                "Oh, you fools!  Dance to your heart's content
                                 in that small world of yours.  Our world is
                                 the whole of space!"   --- Phantom F. Harlock

------------------------------

 

[flykiller]

... the IN doesn't have all that many TL F starship in it's inventory, because there are so few TL F ship yards, most are TL C and D.

in the spinward marches the mora and trin yards alone are larger than all the tech 14, 13, and 12 yards combined.

iytu what imperial naval role, if any, do porozlo and junidy play?

imtu all imperial naval combatants are tech 15. lower-tech vessels going against higher tech vessels simply get slaughtered.

 

[Magnus von Thornwood]

Well...

Basically at this point none, in fact none of my Traveller games have lasted terribly long, for some reason, supers games, run full on campaigns, my famous 1200 point GURPS Illuminated, All Books campaign, ran quite a bit, and boy what a bleeding work out, but for some reason I just can't keep them running in Traveller...perhaps because they seem to end up as pirates or smugglers or some other you will get hosed types...I know bad Ref, but I can't help it my IN is so damned efficient, oh and the players hose each other...sigh.

But in my mental work up of the Imperium, since the only serous High TL Race to worry about is the Darrians, most of the IN is TL C and D with the Battleships and Carriers as the only real TL F vessels. Oh and all my IN tends to run around in squadrons and such so there is also numbers on their side. In the case of war, they get grouped together into Task Forces and Groups.

Truthfully, I tend to enjoy Traveller for it's History more than anything, and thus have devoted much of my brain power over to the larger workings of the Imperium and it's relations with it's neighbors. I have this theory about the Psionic Suppressions for instance....