Long-haul trade

[robject]

I just heard a snippet of an interview with a U.S. civil war historian, who in passing noted that the biggest, most affluent city in the Colonies around the late 18th century (Philadelphia) was shipping 700,000 tons of wheat to Europe each year.

I don't know what that is in displacement tons, but that sounds like pretty serious shippage.

 

[Chuck Anumia]

74% of the people in America were farmers.

Wheat was grown in the North prmarily and Rice and Indigo in the South.

 

[Fritz_Brown]

Well 700,000 metric tons of wheat (not cracked) works out to 65,020 dTons (at 14m^3/dTon). Edit: How many Free Traders is that? end edit

How do I know that?! This webpage has densities for all kinds of bulk materials.

They have things like sandstone (2323 kg/m^3 solid or 1370-1450 kg/m^3 for broken), nitrogen (1.26 kg/m^3), malt (336 kg/m^3), wool (1314 kg/m^3 - so how much does "3 bags full" weigh?), ice ( 919 - solid), water (1000 if pure - oh yeah, we knew that one. ), and even sewage (721 kg/m^3)! A new Traveller resource!

 

[archhealer]

Erm, if water = 1000... That's wrong, isnt' it? Aren't dts liquid HYDROGEN displacement tons?

 

[Fritz_Brown]

Originally posted by Archhealer:
Erm, if water = 1000... That's wrong, isnt' it? Aren't dts liquid HYDROGEN displacement tons?

That's 1000kg per m^3. That isn't a displacement ton, it's an actual mass ton. 1000kg of water would displace about .07 dTons. (No, it wouldn't float.) (1m^3 = 1,000,000cm^3 = 1000l; 1l = 1kg for water.)

 

[robject]

65 thousand displacement tons per year = say 1300 tons per week.

Let's assume a minimal number of passengers as well: say 65 (1 per 20 tons of freight).

According to a very old script of mine (http://eaglestone.pocketempires.com/starports/StarportCapacity.html), 65 people and 1300 tons per week would warrant:

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">Landing : 2 ships (1800 t)
800t : 1
1000t : 1
Passengers: 100
Freight : 300 t

Orbiting : 1 ships (3000 t)
3000t : 1
Passengers: 0
Freight : 1000 t

Downport Components:
Fuel (T) : 720 MCr 7.2
Repair (T/y): 180 MCr 18
Build (T/y): 200 MCr 20

Shuttles (MCr 0): 0 x 100t, 0 x 1000t

Orbital Components:
Berths (T) : 300 MCr 300
Fuel (T) : 750 MCr 75
Repair (T/y): 3000 MCr 300
Build (T/y): 300 MCr 300</pre>[/QUOTE]So, there could be 3 ships per week: 800t, 1000t, and 3000t. The downport would cost around MCr45, and the orbital support would cost around MCr975.

 

[Fritz_Brown]

But, what if its all Free/Fat/Far-Traders, robject?

 

[Whipsnade]

Three words; Economies Of Scale.

I know a guy who gets a measly 1 penny per shower curtain ring. He owns a palatial home on a Carribean island because he's sold BILLIONS of rings.

Ship enough of a low price item at a cost low enough and you can make money. Buy wheat for $1 a ton, ship it for $1 a ton, and sell it for $2.01 a ton and you'll make millions if you only ship enough wheat.

Whether shipping costs in the OTU can be jiggered low enough is an entirely different question. While canon doesn't seem to support it, Real World examples very much do.

Some odd facts:

- Recently launched 'box ships'; aka container vessels, are too wide for the Panama Canal, are longer than USN CVNs, carry containers by the THOUSANDS, and are operated by a twenty man crew.

- Towards the end of the Spice Trade era, pepper - the very substance that had driven European expansion into the Far East in the first place - was being carried as ballast. Other items like porcelein(sic) and tea now more than paid for the voyage, so pepper was just thrown in the hold as an afterthought to fill it up. (It was learned that shipping pepper with tea lowered the price of tea!)

- The beautiful clipper ships of the China Trade almost all ended their sailing days being operated by dangerously small crews and carrying fossilized bird shit from the Pacific coast of South America to the US and Europe. The amazingly low cost of the vessels; they were going to be broken up anyway, and the unbelievably low cost of operating them; shanghaied men and fleeing criminals, meant that the guano trade was a money maker.

Ship enough of anything, ship it cheaply enough, and you'll get your McMansion on Antigua.


Have fun,
Bill

P.S. I once heard the process of divining the nature of megacorp and hi-pop world interstellar trade in the OTU from the canonical trade examples given as being aking to divining the nature of US-China-Europe trade from dhow traffic between Somalia and Aden.

I still believe that analogy to be true.

 

[robject]

I take Bill's comment as proof that a simple, first approximation is better than a complex one, for the purposes of Traveller. As a corollary, I note that the greater should serve the lesser: setting up a complex trade system that does not cater to the simple solution is the tail wagging the dog.

--

Type As, A2s, and Rs? 200 and 400 tons only?

Well, I shifted some numbers around on the traffic tool, limiting the ships to 200 and 400 tonners, and get a much more affordable starport, at the expense of having a lot more ships per week:

</font><blockquote>code:</font><hr /><pre style="font-size:x-small; font-family: monospace;">Landing : 24 ships (7200 t)
200t : 12
400t : 12
Passengers: 360
Freight : 1320 t

No ships orbiting.

Downport Components:
Airstrips : 1 MCr 0.01
Parkbays : 2 MCr 0.2
Fuel (T) : 2880 MCr 28.8
Repair (T/y): 720 MCr 72
Build (T/y): 2400 MCr 240

Shuttles (MCr 0): 0 x 100t, 0 x 1000t </pre>[/QUOTE]24 ships per week is nearly one every seven hours... still a frontier port, in my opinion. But it's very affordable, at less than MCr350!

Note: Assuming three 800-ton mini-freighters to carry part of the cargo would further reduce the starport facilities to a mere MCr180 or so...

 

[Martin]

Couldn't help but pay heed to this post as I have been a merchant ships officer for over 20 years in the real world and have always had a bit of a problem with the scale of Traveller trade in relation to both the worlds involved and the size/number of ships involved. I thought I'd give y'all a couple of points to ponder.

As a prime example a couple of years ago I was involved on one single ship that carried one million tons of iron ore in just five months between two european ports, that was just 10 voyages of 100,000t plus each voyage.

The idea that ships of just a few hundred tons would be economically viable in the future has always seemed quite unlikely. IMTU, I generally prefer much larger scale ships to represent real trade between worlds.

As another example I recently left the sea to begin work as a cargo surveyor and in only one moderate size port here in the USA I carry out inspections on even small ships of over 5000 tons that may be carrying far more cargo than 10 far traders in just one day! Larger container vessels of 120,000t are also one at least one a day in this port alone. Imagine how many are required to keep an Empire flowing.

Anyway just wanted to add to the ideas on trade out there!

 

[Ptah]

thrash

Traveller starships are more like aircraft than surface ships

Is this based on the cost per ton shipped? From the designs and economics I've run with HG ship design, the larger the ship the lower the cost per ton. One distinction between modern aircraft and ships is that it becomes exponentially harder (and costlier) to get a plane to take-off the larger you make it compared to ships. This is not the case with HG ship design for example.

 

[far-trader]

First a welcome aboard Martin Belated I guess

You need to get those post numbers up

Now then, while I like the RealLife(tm) experience side of things to compare to it does usually get my groat. Let's see if I can explain this...

I see comparisons of how much interstellar shipping must happen based on populations by comparing it to the total shipping done around our little globe for it's population and wonder how that can be a valid measure. The stuff we ship around the planet and trade country to country is for the most part consumables that the people here need. We'd be hard pressed to come up with a vanishingly small fraction of that we could do without so we could ship it off-world.

I think the small ship universe is probably closer to the possible reality than the large ship universe as far as trade goes. Worlds like earth won't need much in the way of imports and won't produce much in the way of exports on an interstellar market. Smaller populations with like resources would be major exporters of raw materials and large populations on worlds with fewer resources would be major importers of goods and/or raw materials.

I just wonder where people figure the billions of dTons of stuff comes from and goes to when I see some of the suggested trade numbers for some worlds. I think most worlds will be pretty much self sufficient at a certain level and the bulk of the population won't be interested in leaving or simply unable to.

But don't let my contrary ideas stop you

In fact I'd like to see some reasoning for huge trade numbers between worlds if you have them. Don't worry too much about hard numbers, gut level ideas are good enough.

 

[Ptah]

Originally posted by thrash:
</font><blockquote>quote:</font><hr />Originally posted by Ptah:
Is this based on the cost per ton shipped?

No, purchase price per ton overall. Cost per ton shipped is only relevant if you also discuss turn-around time and voyage length. By that measure, Traveller ships ought to be more similar to surface vessels, but amortizing the huge initial cost over so few voyages skews the economics. </font>[/QUOTE]How many voyages do you amoratize over? I tend to amoratize ship cost over 50 years, i.e., the length of the mortgage factoring in the interest. (I forgot the LBB number for the ship mortgage but I recall it was shorter.) I tend to view these hulls as lasting a 100 years if properly maintained. Unrealistic?
This view of hulls lasting a long time raises its own set of problems. How do you compete with someone who has paid off their ship? IMTU the answer are pricing controls and cartels. IMTU major shipping interests have the Imperium set a minimum shipping cost for cargo. Only those individually owned and operated ships in the spec trade (enter the small 200 ton, 400 ton ships) can offer shipping below this set rate. Hence, the market niche for free traders, etc. Everyone in the shipping cartels is happy. Strange thing though, IMTU pirates seem to have a statistical preference to attack shipping that violates the minimum shipping cost regulations.

 

[aramis]

Welcome, Martin!

Thrash points out one aspect, and I agree with it... Traveller ships have an operational aspect not unlike aircraft, both in terms of costs and realistic limits of operation.

The For simplicty, stick to 5 Registry tons per Displacement Ton (Td); in most editions the Displacement Ton is 14 cubic meters or just about 17.8 cubic yards.

Remember, though, that spacecraft have transient stress loads of up to 3-4 times their G rating in atmosphere, and up to double in some non-atmospheric cases. This means massive structural needs in order to stay intact. Few wet-naval craft experience transient G-loads in excess of 3G; even then, that's high storm wave loading on near-harmonic wavelengths... spine breakers. Past a certain point, one can no longer effectively stress the hulls, since the strength of structural members is a function of cross section, and the mass-loading is a function of volume: the square-cube law. Likewise, radiative heating is affected in unhappy ways by the square cube law.

While naval ships suffer from the square cube law, they have the advantage of not having to hold their weight up on the keel, only to push it on the keel.

Spacecraft, however, are like fore-and-aft pod-thruster naval ships: they can produce thrust loads and need to be able to transfer thrust from both ends, and often the middle.

Further, the intense needs for life support are far more like subs than surface craft, or even aircraft. And, like subs, any pressure hull leak is a catastrophic failure. But, unlike subs, there isn't even the possibility of sending divers out to spearhunt food, nor is there water available. (Of course, in sealed LS, water needs to be managed very carefully. Humans release an awful lot... )

But then we have to add the unique hostilities of space: High radiation levels (much of it easily stopped by hull shells). Microids (micro-asteroidals) which can hit with forces comparable to major artillery.

Summary

Aircraft-like: need for full-load hull. Available thrust levels. Potential for sudden multi-G transient loads. Possibility of liquefaction failures of structural members.

Surface Naval Similarities: Travel times. Crew rates.

Submarine Similarities: Life support needs. Results of integrity failures. Isolation from exterior.

Unique to spacecraft: radiation levels. microid damage.

 

[shadowdragon]

you could look at it this way- most large volume cargoes like grains, ore, water, chemicals etc.... are prolly going to be handled by huge bulk freighters for the interstellar part of shipping. once the shipping becomes inter- or intra- planetary smaller vessels will come to the fore.

think tramp feighters of the early 1900's.
i dont see a 400 ton free trader hauling ore, wheat, etc.. and making a profit under most circumstances. i see 400 ton free traders hauling low bulk high value items, high bulk super high value (400 dtons of gold sounds fine to me)items and people. bulk freighters will always be the mainstay of the galaxy, but tramp freighters will be the cheaper, faster alternative to the set shipping runs. the main shipping runs of the vast bulk freighters will hit the mainworlds of a sector, dropping and loading cargo at each stop. smaller freighters will then pick up the cargo to take it out to the less "important" worlds of the sector, and even smaller ships out to the addtional system planets of each system served.

a huge intersteller freighter won't stop at sol 3 and again at sol 4, it will dump everything for the system at sol 3 and let the sol system freighters work out distribution headaches.

container ships to trains and tractor-trailers, to box trucks to vans to consumer. not perfectly accurate but it will serve.

 

[Black Globe Generator]

Originally posted by shadowdragon:
container ships to trains and tractor-trailers, to box trucks to vans to consumer. not perfectly accurate but it will serve.

And most Traveller adventurers are the guys selling speakers out of the back of a van in a shopping center parking lot.

 

[Fritz_Brown]

How true, BGG, how true!!!

(Edit: Not that there's anything wrong with that, mind you!

end edit)

 

[epicenter00]

And most Traveller adventurers are the guys selling speakers out of the back of a van in a shopping center parking lot.

Speakers? I'm less sure about speakers. More like rolling up in a Merkava to a strip mall parking lot and selling a combination of boxes conspicously marked "ARMY USE ONLY", Mayan stelae hastily chainsawed and similar priceless cultural treasure brutally looted, and ... okay and speakers.

After all this, they demand to know why the cops, the BATF, and the national guard show up and point guns at them because they're Streetwise-4 and Stealth-4.

 

[graymask1120]

Originally posted by Fritz88:
[QB] Well 700,000 metric tons of wheat (not cracked) works out to 65,020 dTons (at 14m^3/dTon). Edit: How many Free Traders is that? end edit

65,020 dtons ÷ 67 dtons (the cargo capacity of a 'Marava'-class) = 4,356,340 loads.

Divided by 200dtons (the cargo capacity of a Fat Trader/Subsidized Merchant), that equals 325.1 loads.

 

[Anthony]

Um. In your first example, you multiplied rather than dividing. 65,020/67 = 971 loads.