phavoc said:
...And a well-designed vessel will take into account future work and, for example, route power and control cables away from say the roof of the vessel so you can at a later point cut the roof, lift out the engine, drop the new one in and then weld it back together.
Spoken like a user and not a mechanic
Granted you do caveat your statements but in the real world that is seldom the case. More often simply servicing many parts of a complicated machine requires serious dis-assembly of parts not related to the area of interest. I've long suspected designers and engineers of collusion in making the mechanic's job as difficult as possible, increasingly so over the years. Used to be lots of room for access in an engine bay, and routine work was a breeze. Now you have to practically (or actually) remove and /or partly dis-assemble the engine to do anything beyond changing the fluids and filters. And sometimes the filters aren't that easy.
The days of quickly and easily field stripping and reassembling the original jeep are long gone. For one thing the replacement is a lot bigger and heavier. No doubt the military does design with a mind to quicker service but you don't see that in civilian designs.
As for cutting up huge sections of hull to remove drives from a starship, I see several problems with that being the method. Structural integrity, jump grid (if you use that), and fuel buffer (if you use that) off the top. More likely (and the way I've drawn a few) the drives will be disassembled and removed in pieces through the thruster hole(s). So if you need to replace the jump drive, first you have to dis-assemble the maneuver drive and remove it (at least one thruster unit), then dis-assemble the related power plant(s) and remove it through the thruster space, before finally being able to dis-assemble the jump drive and remove it through the power plant area and out the thruster space. Then put it all back together by reversing that. A procedure that will take considerably more time than the original installation which was probably a matter of building the hull around the drives.
Optionally on some merchants the procedure may be done through the cargo bay (via hatch or wall removal) and out the cargo hatch.
What I'm saying is retrofit time will vary by design (size generally) and the part(s) involved (complication). And it could very easily be longer that the build time for the whole ship. Just look at how quickly a car is assembled on a modern auto production line, compared to even some of the simpler maintenance time on parts buried deep in the engine
So, make it up
Let the story dictate. If you have an adventure you're dying to use, then that is how long the player's ship is laid up. Or work up a simple formula to generate a base estimate if you want some consistency and expect it to happen more than once.
(j/k)
