Re: [Spaceships]Traveller Ships with economics
 

Comparing the cost per passenger or cargo ton for a range of ships built to the same method as above gives:

Cargo ton per parsec
$730 J1 Cargo Liner
$710 J1+J1 Cargo Liner
$770 J2 Cargo Liner
$930 J2+J1 Cargo Liner
$1050 J3 Cargo Liner
$900 J2+J2 Cargo Liner
$1500 J4 Cargo Liner
$1100 J3+J2 Cargo Liner
$2900 J5 Cargo Liner
$1400 J3+J3 Cargo Liner

$900 J1 Beowulf
$930 J2 Marava
$1300 J3 Long Trader

Passenger Price* per parsec
$4400 J1 Passenger Liner
$4300 J1+J1 Passenger Liner
$4100 J2 Passenger Liner
$5000 J2+J1 Passenger Liner
$5300 J3 Passenger Liner
$4800 J2+J2 Passenger Liner
$7600 J4 Passenger Liner
$6200 J3+J2 Passenger Liner
$15000 J5 Passenger Liner
$6900 J3+J3 Passenger Liner
$34000 J6 Passenger Liner

$9000 J1 Beowulf
$9300 J2 Marava
$13000 J3 Long Trader

And this assumes the same utilization and stopover times for the Tramps as the liners.

Conclusions:
The Refinery needed by tramps to allow wilderness refuelling for adventuring purposes significantly reduces their profitability when competing in places where refined fuel is available.

Tramps need to charge at least 25% more than Liners for cargo, and probably at least 50% more as they will tend to have emptier holds.

Tramps need to charge at least double for passengers.

Cargo wont travel by anything above Jump-2 unless astrography dictates and will almost certainly travel on double hop liners on single jumps that are four or more parsecs.

Passengers probably wont travel above Jump-4 on liners and Jump-2 on tramps. They may take lower TL and cheaper double-jump liners on four or more parsec gaps.

*Passenger sharing a cabin. Luxury passengers and single occupancy passengers pay twice this. Low Passengers pay half this.

Economics are based on: 12% of ships cost repaid/year, depreciation 8%/year, $10K/month/crew member, Insurance 1.2%/year, 5% RoC, 90% utilization.

Re: [Spaceships]Traveller Ships with economics
 

You realize that these are not even remotely like the canonical values? They're not wrong by any means -- probably more realistic, if the truth be told -- but then the results aren't comparable to what has been previously published for Traveller.

Re: [Spaceships]Traveller Ships with economics
 

The mortgage and insurance are from G:Spaceships 2. Utilization is from Far Trader. Salary is a generalized figure off the Jobs table and has minimal impact anyway. I extrapolated depreciation based on mortgage period.

I would rather be more "realistic".

Re: [Spaceships]Traveller Ships with economics
 

So would I, especially where the canonical material implies persistent economic disequilibrium (a.k.a. opportunities for [supernormal] profit, a.k.a. "economic perpetual motion machines", a.k.a. "money trees").

Far Trader made an heroic effort at eradicating the money trees in freight transport demand (though I conclude on examination that it ought to have considered J-3 trade routes). I would be nothing averse to attacking the disequilibriums in transport supply.

Re: [Spaceships]Traveller Ships with economics
 

On a 4-parsec leg the J4 saves one week at a cost of G$2,400 per ton. With the interest rate on commercial paper at, say, 7% that's economic on freight worth G$1.7 million per ton or more. I doubt that there is enough volume at that sort of value to keep J-4 lines in business.

The J-2 liner is both faster and cheaper.

On a 4-parsec leg the J-4 liner saves one week at a cost of $11,200 per passenger (middle passage). It will be preferred only by passengers with BVOT of G$1,600 per day or more. That probably includes executives and professionals. But the high generalised cost of a trip (at least G$41,600 one way, including G$30,400 fare plus at least G$11,200 value of time) and the small economic volumes of planets in the TU suggest that potential traffic volumes will be small, probably too small to sustain a line, especially given the sensitivity of such travellers to headway and the long cycle times on thin routes.

The J-5 liner saves one week at a cost of G$32,400 per passenger (middle passage). It will be preferred over the J3+J3 only by passengers with a BVOT over G$4,630 per day. Such people exist, but there probably aren't enough of them to keep lines in business.

J3+J3 liners will be challenged by J3+J2 liners with more staterooms and fewer fuel tanks, which will still further thin the market for J5 liners.

On a 4-parsec leg with a potential refuelling stop in the middle, the J2+J2 saves the trip in from the 100D limit and back and waiting/refuelling time at the intermediate port, at a cost of G$2,800 and the opportunity for a brief stop-over.

Re: [Spaceships]Traveller Ships with economics
 

Interesting.

Converting those figures to a per-Jump basis for convenience we get:

$4,400 J1 passenger liner
$8,200 J2 passenger liner
$9,600 J2+J2 passenger liner
$15,900 J3 passenger liner
$30,400 J4 passenger liner

Let's consider the route from Regina to Aramis as an illustrative example.

The distance is 12 parsecs, but astrography does not allow a (J2, J2, J2, J2, J2, J2) route. The (J2, J2, J2, J2, J2, J2, J1) route [Regina, Yori, Treece, Kinorb, Risek, Henoz, L'Oeul d'Dieu or Vinorian, Aramis] takes 64.5 days and would cost G$53,600.

[Regina, Yori, Treece, Kinorb, Risek, Henoz, Aramis] is (J2, J2, J2, J2, J2, J3) takes 55 days and would cost G$56,900.

[Regina, Yori, Treece, Kinorb, Risek, hex 2911, Aramis] is (J2, J2, J2, J2, J2+2, J2+2) takes 53 days and would cost G$52,000. It is both cheaper and faster than the route with the extra refuelling stop and the route with the J1 leg.

[Regina, Yori, Inthe, Risek, L'Oeul d'Dieu, Aramis] is (J2, J3, J3, J3, J2) takes 45.5 days and would cost G$64,100. Contrary to the case in Far Trader costs it does not dominate the best six-Jump route: indeed it is preferred only at BVOT above G$1,600 per day, which is fairly high.

[Regina, Yori, Inthe, Risek, Aramis] is (J2, J3, J3, J4), takes 36 days and costs G$70,400. That is preferred over the 5-Jump route at a BVOT of only $665 per day, which includes all passengers who prefer the 5-Jump route over the 6-Jump route. The 5-Jump route is uneconomic, and the four-Jump route is preferred over the 6-Jump route by all passengers with a BVOT over G$1,080 per day.

[Regina, Treece, Risek, Aramis] is (J4, J4, J4), takes 26.5 days and costs G$91,200. It is preferred over the J-4 route by passengers with a BVOT over G$2,190 per day.

We conclude that there are only three economic services between Regina and Aramis.

• Passengers with a BVOT under G$1,080 per day prefer [Regina, Yori, Treece, Kinorb, Risek, hex 2911, Aramis] in a J2 liner transshipping at Risek to a J2+J2 liner.
• Passengers with a BVOT between G$1,080 per day and G$2,190 per day prefer [Regina, Yori, Inthe, Risek, Aramis]. J2 on the first leg, J4 on the last, transshipping twice.
• passengers with BVOT over G$2,190 per day prefer [Regina, Treece, Risek, Aramis] in a J-4 express liner.

G$1,080 per day is not a very high BVOT. The J4 service Aramis-Risek may be viable.

Re: [Spaceships]Traveller Ships with economics
 

Interesting. I will analyze later.

Note: I added in the missing liners above:

$930 J2+1 Cargo liner

$5000 J2+J1 Passenger Liner
$6200 J3+J2 Passenger Liner
$34000 J6 Passenger Liner

Re: [Spaceships]Traveller Ships with economics
 

You seem to be using around 9.2 days per jump (though I thought you were using 9.5), so shouldn't this be 27.6 days. And BVOT looks only to be around G$1540.

I think there is a fourth. I am quite liking a J2+J2 liner on that last route. Only G$57600 and 48.6 days. BVOT of G$1270 per day. Faster than the seven, and both six jump routes.

And with the BVOT spreads now close together at 1080, 1270 and 1540 I suspect that it collapses to the base route and the J2+J2 liner route - or maybe even just the cheap J2+J2 liner route. No transshipping, and the slightly slower pace gives the demand a chance to build between visits.

Re: [Spaceships]Traveller Ships with economics
 

I'm using 9.5 days per Jump minus 2 days for passenger time, because I figure that passengers will not come aboard for initial loading or stay aboard for final unloading. But in the case of ships taking a double Jump I slice off another 2 days at each deep-space Jump because I reckon that it will not be necessary to cruise in from the 100D limit or to unload, load, and fuel between the Jumps.

Sometimes I make arithmetic errors, especially when I don't do a formal plot. But in this case I think I had it right. Compared with the next slower economic option this saves 9.5 days at a cost of G$20,800, which is G$2,190 per day.

Six Jumps in a J2+J2 liner at 7 days each, with two port calls (at Treece and Risek) at 2.5 days each, half a day for each deep-space Jump, and half a day for the ends. That's 49 days on the basis I was using. Six Jumps at G$9,600 per Jump is G$57,600.

Compared with [Regina, Yori, Treece, Kinorb, Risek, (hex 2911), Aramis] (53 days, G$52,000) it is 4 days faster but $5,600 more expensive. It would be preferred at a BVOT of G$1,400 per day or above. Compared with [Regina, Yori, Inthe, Risek, Aramis] (36 days, G$70,400) it is 13 days slower but G$12,800 cheaper, so it is preferred at BVOT below G$984 per day. There are no BVOT values that are both below G$984 and above G$1,400, so all passengers prefer on of the alternatives and this service is not economic.

I figure that it has a narrow niche if the time between arriving and departing at a deep space Jump is short.

Well, demand building between visits is a double-edged sword, since it means that you lose a lot of passengers whose BVOT is high because they have to meet a deadline. (This is the problem of headway.) Express services need a short headway to be viable, because wait time for the service is a cost in time-critical applications, even if the wait time can be used productively.

Re: [Spaceships]Traveller Ships with economics
 

Thanks for those enlightening explanations. I think I am beginning to more fully understand it now.