On 16/10/21 21:43, Timothy Collinson - timothy.collinson at port.ac.uk
(via tml list) wrote:
> Following the report on TML of the death of Bill Prankard I did as I
> said and had a look at the things he was credited with for Traveller.
>
> One of which was _GURPS: Starships_ (as 'Other contributions by').
>
> Browsing through I firstly remembered what a treasure house this is
> even if I'm unlikely to build ships using it. Secondly I came to page
> 22 and was reminded of the 'Maintenance Requirements' that I've not
> looked at in ages (years) and never tried actually using.
>
> Oh, brilliant!  I thought.  Maybe this was something I could use to
> better structure jobs and repairs for our engineer on the March
> Harrier.  So I dutifully dug out my calculator as I can't do square
> roots in my head.  I've shown my working below just in case I *have*
> fouled up the math(s) which I wouldn't be surprised at.
>
> And immediately ran into "is this right?"  "I must be doing it
> wrong?"  "is there something I'm not understanding?"  "is there
> something I'm missing".
>
> So,
> "To calculate a starship's maintenance requirements, use;
> Maintenance = 4.8 x original purchase price in MCr / (square root of
> actual purchase price in MCr)
> The result is the number of man-hours per day required for maintenance."
>
> (I should say in passing that it seems odd to base this on ship cost
> rather than ship size but I can see a kind of logic and I suppose it
> means that all those luxurious noble yachts are being kept in tip top
> condition.)  Anyway.
>
> I immediately grabbed the March Harrier's price: MCr101.03 [1],
> decided I'd pretend for the moment that it was brand new and plugged
> in the numbers.
>
> = 4.8 x 101.03 / 10.05
> = 4.8 x 10.05   [2]
> = 48.25
>
> !!!
> That's quite a bit more maintenance than I was imagining. With 8 hour
> days it suggests six engineers!  (For a 400-ton ship!).  Even if The
> Captain wields a cat o'nine-tails and drives them to 12 hour days
> you're looking at four of them. This for a ship that is supposed to
> only require 1 engineer.
>
> Don't forget it gets worse if we know the ship is 100+ years old and
> presumably worth nowhere near its original price.  I think there are
> rules for that somewhere but I couldn't be bothered to hunt for them. 
> Let's pretend the March Harrier is only worth 80% of it's purchase
> price now.
>
> = 4.8 x 101.03 / 8.99
> = 4.8 x 11.24
> = 53.94 hours!
>
> Hmmm, I thought, maybe there's a large difference in ship costs
> between classic _Traveller's The Traveller Adventure_ and GURPS Traveller.
>
> Well, let's keep it simple then and take the (old style) subsidized
> merchant from the _Starships_ book itself.  Here we are, p.93 the
> /Colresh/-class Subsidized Merchant: Price: MCr92.1.  Not so far off. 
> This one requires two engineers - as does the 'standard'
> /Akkigish/-class of GURPS Traveller (p.146) although the latter only
> costs MCr57.2174.  So let's see what that does for us:
>
> Colresh
> = 4.8 x 92.1 / 9.59
> = 46 hours!
> Hardly any better.  2 engineers would still be getting only an hour's
> sleep each!
>
> Akkigish
> = 4.8 x 57.21 / 7.56
> = 4.8 x 7.56
> = 36 hours
> Well, at least two engineers are now getting 6 hours a night sleep
> with no free time.
>
> Just to see if different ships mattered, I tried the 100-ton Scout. 
> In _Starships_ you've got the Iiken-class which costs MCr51.7 but at
> least it requires *four* engineers (along with pilot and co-pilot)
> (p.92).  The standard Sulieman-class in the core book (p.130) is
> MCr26.3796 and (usually) has one engineer (as well as pilot and co-pilot).
>
> Iiken
> = 4.8 x 51.7 / 7.19
> = 34.51 hours
>  - that's better - a 6 hour day (34.5 / 6)!
>
> Sulieman
> = 4.8 x 26.37 / 5.13
> = 24.6
> (well, not much else to do in Jump!)
>
>
> Just for fun, although I appreciate it's probably not fair comparing
> different rule sets, I ran the numbers for three Mongoose 2nd Edition
> ships: Free Trader - 32 hours with 1 engineer, Scout - 29 hours with 1
> engineer and Sub Merchant - 43 hours with 1 engineer.  (Again,
> assuming they're new.)
>
> So, have I missed something?
> Or are all Traveller ships just massively behind on maintenance and
> that's why they need their annual maintenance and are generally quirky?!
> Is it possible they meant hours of maintenance per week?! (And my
> apologies if this is a known erratum - although this would imply not:
> http://www.sjgames.com/errata/gurps/traveller-starships.html - or if
> TML has been round this buoy before - I should have searched.)
>
> It does seem as if I've been massively underworking our engineer!
>
> Or should I just accept these rules aren't fit for purpose?
>
> tc
>
>
>
> [1] _The Traveller Adventure_, p.109
>
> [2] Yes, with rounding I might as well have just done this in my head
> as MCr100/10!
>

Collision,

You don't seem to be the first person to trip over this -
http://www.elvwood.org/Traveller/Maintenance.html tilts at this same
windmill.  He starts with the square root of powertrain power, then
modifies it for TL (presumably TTL), powerplant type, and drive train.

To use the _Butcher's Paradise_ as my example, per GT:S (base price
approx M$ 75 and taking solars as equivalent to CrImp for this purpose):

New: 4.8 * 75 / 8.66 = 41.6 man-hours/day. As if Nikki didn't have
enough to do all bloody ready....

As-purchased (25% off, second hand): 4.8 * 75 / sqrt ( 75 * 0.75 )

4.8 * 75 / sqrt (56.25) = 48.0 man-hours/day.

Taking MGT2 power points as megawatts (and giggling at the image of Das
Boot black-starting a collapsed power grid), the ship has 120,000 kW of
powertrain, is built at TTL12, uses fusion reactors, and has
reactionless thruster/jump drive/contragrav drivetrain.

sqrt (120,000) * 0.012 (TTL12) * 1.0 (fusion reactor) * 1.0
(reactionless/jump drive)

= 346.42 * 0.012

= 4.2 man-hours/day.  Wouldn't be a problem for most engineers, but
Nikki is also first mate, lawyer, purser, spec trade specialist, etc.

Under MGT2 rules, Das Boot is unusual in that it can fight, run _and_
prep for jump at the same time (seems to be a Terran veteran thing
IMTU).  You can do the numbers yourself for an 80 MW powertrain.

Going up the big end of town for the ISW, we have the _Indomitable_
class 30 kiloton battlewagon (whether battlestar or battleship, am not
sure).

Per its GT:ISW writeup, damn thing costs 32 G$.  It also mounts 8,182
dton of fusion power plant that can generate a sustained total of 163.6
GW - if six of those put down on CONUS, I think that's the contemporary
continental USA's power grid covered.

GT maintenance would be 4.8 * sqrt (32,000) = 858 man-hours/day.

Elv maintenance would be sqrt (163,600,000) * 0.011 (TTL13, at a guess)
* 1.0 (fusion) * 1.0 (starship drivetrain) = 140.7 man-hours/day.

I'm still putting together the Tigress' power demands.

Alex