by Jim Wallman
Interstellar trading has to be planned well in advance.
The high cost and fairly long journey times mean that merchants
cannot wait for the shipping to arrive before working out what is
being traded for what. Deals and commodities are organised well
in advance of the arrival of a cargo ship - the things being shipped
out be waiting at the orbital station so that turn-around times
are minimised - maximising profit for the shipping operator. Orbital
dockside operators and specialised import-export companies are important
in managing the process.
Therefore, the route and ports of call for any merchant ship must
be planned for months or even years ahead.
Overheads for shipping companies are pay, ship maintenance costs
and ship purchase repayments (or a leasing arrangement). Pay is
significant, because each ship will have more than one crew to allow
for leave, courses and the like (health an safety law requires crews
to have a certain proportion of their working year planetside).
Merchant ships come in five main classes, based on the five main
types of hyperspace drive (there are more, but this is a useful
simplification based on the taxation categories used by the Imperial
Typical Crew size
Operating Cost per tonne / day
|Smallest practical field size (small ones exist, but
you can't fit a ship capably of interplanetary journeys inside
|Maximum field size.
Note: Tonnages are slightly changed from the rules because
I've been playing with the sums a bit.
Operating costs vary for each class and depending on whether it
is being leased or bought via a loan or is fully owned (having paid
off the loan). Typically ship purchase loans are paid back over
10 years, and the vessel has an expected safe operational life of
up to 24 years.
As shown above, smaller classes are slightly less cost effective
than the biggest - but sometimes, especially where trade is developing,
a trader can't fill a Class 5000, so it makes sense to use a smaller
ship, even if the cost per tonne is a bit higher.
This is especially so in the outer colonies, where trading corporations
have complex transport logistic plans to maximise the use of their
varied fleets. And for areas where the gains are more marginal,
small, independent traders (who can only afford to buy the smaller
ships, pick up the work).
Independent Traders are also able to cut their margins by lengthening
the service life of their ships beyond the manufacturer's recommendations,
lengthening routine service and refit intervals, and pay crew higher
rates (illegally) to forgo shore leave. Some even avoid paying ship
tax - falsifying records by creating 'ghost ships' - that is more
than one ship with the same registration and tax record.
So, the operational economics of shipping lines is such that they
are vulnerable to crew pay fluctuations, fluctuations in ship purchase
interest rates, fluctuations in refit and service costs (different
systems charging different rates), fluctuation in government shipping
tax, port taxes and the corner-cutting activities of semi-legal
independents. Not to mention the cost of losing ships to pirates
or STUFT duties.
This is covered, in many cases by the size of the multinational
big shipping lines, who may own hundreds of ships, Universe-wide,
and have huge financial influence and resources. Independents, obviously,
go in and out of business regularly.
Some working assumptions about frequency of shipping
We assumed a while ago that the merchant starfleet was many times
the size of the military one. My estimation is that there are probably
around 1000 military vessels of various types. Let us say there
are 30 merchants for every military, and if we assume an approximate
stellar population of around 800 worlds, then there is an average
of around 30-40 ships per world at any one time.
Lets assume the average journey time between worlds were 24 days
- 8 days out to M25, 8 days HS transit, 8 days in from M25 and then
8 days loading/unloading (I have no idea if this is the case, but
it's in the right area).
Then, on any given day in The Universe at a given colony system:
- 10 ships in transit leaving,
- 10 ships in transit incoming,
- 10 ships in hyperspace somewhere and
- 10 ships in dock, loading / unloading.
It might be a bit less than this, because a proportion of the
merchant starfleet would also be under repair or undergoing routine
refits or maintenance - but it gives us a ball-park figure. It would
be a quite a bit more in the Home Systems.
So..what about pirates
We have assumed that piracy is a common problem.
My assumption is that pirates operate under cover of local corruption,
passing for legitimate merchants most of the time. I can't see the
economics of pirate bases out in the depths of space working (fun
though they are to duff over).
When do they strike?
They have to match velocity to attack. If we assume a slight G
advantage, this might be possible in a tail-chase out to the M25.
Hanging around on the M25 is pointless, since they
couldn't possibly detect an incoming merchant and intercept it in
time. (A military ship might be able to do this, but not a pirate).
The best time is probably quite near an orbital station - but
timing is vital if they are not to be intercepted by security forces.
So the factors are:
- An incoming merchant is moving quite slowly and therefore easier
to intercept, since it is at the end of a long decelerating burn.
- The pirate can mask its intercept by apparently leaving the
station on legitimate business.
- If the intercept takes place, say 6-12 hours out from the station,
the starguard (whose ships are no better than the pirate in agility)
probably cannot get underway fast enough to catch the pirate before
it reaches the M25. Also combats - boarding etc only
takes 10-15 minutes - so even if the merchant gets out a signal
of being under attack - the security forces couldn't possibly
- Of course, if the pirate had just left a station, it could
be identified. Pirates might go to some lengths to disguise their
- Pirate ports are normal colony ports where a pirate can be
refitted and supplied (and fence its goods) with no questions
asked. These are usually corrupt places where the local authorities
are in the pay of pirates. The ruling polity very probably doesn't
know that this is what is going on - because, after all, no governor
is going to report his own corruption.
- Pirates will therefore rarely attack ships leaving a pirate-friendly
port, because that would make things difficult (though they might
do so occasionally to maintain its cover - a system which is never
attacked by pirates might be a bit obvious).
- Pirates escaping a system might choose to take a high-risk
vector to shake pursuit. Normally ships exit a system via 'north'
or 'south' of the plane of the ecliptic. The closer to the POTE
a course goes the greater the risk of catastrophic collision with
a grain of sand. It is then a case of playing the odds - starguard
will rarely risk all to chase down a pirate.
- An important commodity for pirates would be merchant itineraries.
These would change hands for large sums because it would enable
pirates to do things like predict the arrival of a valuable cargo
and possibly even do an M25 intercept.
In many colonial systems, there are also often asteroid mining
operations and other things some distance from the relative safety
of the colonial station. Mining bases (which are usually small
spinning orbitals) are permitted to carry point defences like multi-cannon
- but routine interplanetary trips by miners and their cargos might
be prone to raid from space pirates also. Very daring pirates might
raid miner bases themselves.
Statistics - incidence of piratical attacks