Handling maintenance and overhauls for GURPS Spaceships

[Calvin]

I'm going to be giving my PCs a ship in an upcoming session, and I'm trying to figure out the rules for maintenance and overhauls.

My general idea was to give them a Cheap ship so that fuel and maintenance costs would offset any income from moving cargo so that PC wealth doesn't get out of hand. I've also got general upgrades outlined for them (removing some unneeded modules, adding habitat modules to empty spaces, replacing cargo bays with something else, etc.) but I'd also like to give them the option of overhauling the existing modules.

Basically the idea would be to let them repair a module to the point where it stops being Cheap, and so stops counting for maintenance purposes. But what would this cost? The upper bound for what it costs is simple, it's 80% of the module's normal cost. If it was 80% or more it would be cheaper to simply sell the module (At 40% of the cheap module's price) and buy a brand new one. The lower bound has got to be 50% since if it were cheaper it would be possible to buy a cheap module and then overhaul it to standard quality for less than the price of a new module. Are there even rules for this?

It is possibly stretching the bounds of reality, I know that it might very well be too expensive to get something back in order if it's in really terrible repair. But I would like it to be an option for the PCs, if only to create a money sink to handle wealth inflation.

As a related question, does it make sense for the engineer PC to be able to reduce maintenance costs by their monthly wage per month worked on the ship?

[Frost]

Originally Posted by Calvin

Basically the idea would be to let them repair a module to the point where it stops being Cheap, and so stops counting for maintenance purposes. But what would this cost? The upper bound for what it costs is simple, it's 80% of the module's normal cost. If it was 80% or more it would be cheaper to simply sell the module (At 40% of the cheap module's price) and buy a brand new one. The lower bound has got to be 50% since if it were cheaper it would be possible to buy a cheap module and then overhaul it to standard quality for less than the price of a new module. Are there even rules for this?

There are no rules for this as such, the nearest approach would be the refitting rules from space ships 6 (page 6) I.e. cost of new systems +30% less the cost of selling existing gear for scrap. However these rules assumed an all or nothing process reworking most of the ships systems at the same time.

Originally Posted by Calvin

As a related question, does it make sense for the engineer PC to be able to reduce maintenance costs by their monthly wage per month worked on the ship?

No it doesn't. The engineer is there to keep things running they probably don't have the time or the resources to to make that kind of change to most systems. That is what yard level refits are for. The exceptions are changing fully modular systems and reworking habitat spaces or weapons and these would still require additional investment for new systems and almost certainly need the ship to be in dock while the work happens (again see SS6; 6).

[Anaraxes]

Originally Posted by Frost

The engineer is there to keep things running they probably don't have the time or the resources to to make that kind of change to most systems.

Though you could make an argument for having _extra_ engineers, above and beyond the required crew. Still issues with facilities and tools. You can't do everything under the local shade tree-like flora with your box of hand tools. But you could work out some sort of reduction.

As for comparing prices, it's not a bad place to start. But sometimes replacing something in place in a completed product is just more difficult, time-consuming, and expensive than installing a better-quality new version in the first place. Ever remodel a kitchen or replace the heating and AC units in a house -- never mind rewiring one for Ethernet? Definitely harder than being able to choose your time during initial construction.

[Frost]

Originally Posted by Anaraxes

Though you could make an argument for having _extra_ engineers, above and beyond the required crew. Still issues with facilities and tools. You can't do everything under the local shade tree-like flora with your box of hand tools. But you could work out some sort of reduction.

This may work for in flight refitting of habitats and possibly weapons but I still think that for the bulk of ships systems you are looking at yard work.

[Frost]

While we are discussing overhauls and upgrades how would you handle re-engineing a ship?

For example trying to shoehorn a water propellant engine into the freighter you are trying to militarise in place of its lower thrust hydrogen unit.

My thought would be treat it as any other refit but requiring an engineering roll to prevent serious problems (typically lowered HT) developing. Might there be a better way? Or should I give up on the idea?

[safisher]

Originally Posted by Frost

While we are discussing overhauls and upgrades how would you handle re-engineing a ship?

For example trying to shoehorn a water propellant engine into the freighter you are trying to militarise in place of its lower thrust hydrogen unit.

My thought would be treat it as any other refit but requiring an engineering roll to prevent serious problems (typically lowered HT) developing. Might there be a better way? Or should I give up on the idea?

Yes, Engineering (Starships) is on some templates, so I'd use it. Maybe require a Mechanic skill at penalty, and/or a specific Mechanic skill in the specialty -- that seems one of the few ways to justify picking the specialty ones. The high-performance ones might be trickier to install in a civilian craft, and so penalties are in order. Also, might extend the time for refit for certifications, flight tests, validations, etc.

[johndallman]

Originally Posted by Anaraxes

Though you could make an argument for having extra engineers, above and beyond the required crew. Still issues with facilities and tools. You can't do everything under the local shade tree-like flora with your box of hand tools. But you could work out some sort of reduction.

Warships are supposed to be able to do self-overhauls, at least in some navies and some historical periods. But this is probably a consequence of their large crews, all trained in maintenance to keep them busy.

[RogerBW]

Originally Posted by Kale

If enough tweaks are applied to the stock design it starts getting really confusing. Even if the engineer making the tweaks carefully documents the changes (I am an engineer and we almost never ever do this unless contractually/supervisorally obligated) then the guts of the major systems are going to be a patchwork mess. What you gain in efficiency you will probably lose in reliability.

Sure, I was specifically thinking of Calvin's comments on what an individual engineer can do without full shipyard facilities.

Originally Posted by johndallman

Warships are supposed to be able to do self-overhauls, at least in some navies and some historical periods. But this is probably a consequence of their large crews, all trained in maintenance to keep them busy.

Hmm, depends on what you mean by "overhaul" I think - at least post-WWII, there seem to be three levels of maintenance going on.

(1) Regular keep-stuff-running, done by the crew.
(2) After a long deployment, time alongside in the home port; some crew are helping with major maintenance along with the shore-based techs, but most are on leave.
(3) After several years in service, full-on shipyard time for refits and upgrades.

[johndallman]

Originally Posted by RogerBW

(1) Regular keep-stuff-running, done by the crew.
(2) After a long deployment, time alongside in the home port; some crew are helping with major maintenance along with the shore-based techs, but most are on leave.
(3) After several years in service, full-on shipyard time for refits and upgrades.

What I've encountered in various 20th century histories was Royal Navy vessels far from home doing (2) with just the crew, somewhere that there was a dock and supplies, but no dockyard personnel. For example, HMS Cumberland was doing this in the Falkland Islands at the time of the Battle of the River Plate, and had to stop it and rush north when she heard about the battle.

[Frost]

Originally Posted by johndallman

Warships are supposed to be able to do self-overhauls, at least in some navies and some historical periods. But this is probably a consequence of their large crews, all trained in maintenance to keep them busy.

I'm not sure how true this has been since say the 1870's, steam engines and steel hulls would have put a severe crimp on the kind of things earlier crews could have done. Before this point most things could be done by the crew with hand tools and a secure anchorage. After this point even if the crew can do the work they will probably need a proper yard to do it in [partialy ninja'ed].

How this carrys over will depend upon the setting. Either way I would be reluctant to assume this is going to provide a basis for what the OP wants firstly because it mostly applies to warships with large crews and systems that are readly accessible to facilitate damage control and secondly because it still doesn't offer a precedent for underway refitting.

In most settings this might justify letting the players deduct crew salaries from the 30% surcharge for crew members with relevant skills as a replacement for hired workers in yard based refits. In settings that stick closely to age of sail tropes (say something close to David Drake's Reaches or RCN series) I might let the crew set up an improvised dock and do the work without the surcharge over a longer period of time.