As i understand, Workshop is creating planes without pilots.
By the way,
@Bki - i was under impression that our planes is eldrich abominations "part of the ship, part of crew". Or workshop creates bodies, spirits animates them and turns to such abominations?
Hum... This is tricky... There's no definite canon on the subject (though there's little definite canon on anything).
So, let's see...
Fairies are an existence intrinsically linked to shipgirls (and abyssals). While they're separates existences, they need the presence of one nearby to exist. The vast majority as some sort of "imprint" of the crew, and especially those that died with her.
But not all of them trace their origin back to the crew. The ones that worked on the ship, whether it was during construction, repairs, maintenance... They're also represented. Hence, for example, the constructions fairies.
That's basically it for the shipgirls. But, Abyssals are slightly different, they have a deep connection with those that died at sea. The sailors, obviously. But also all those civilians that the sea claimed for various reason, in war or in peace. And, the numerous aviators that died over the pacific... Their feelings, their regrets, their curses, as they were engulfed into the abyss... They persist, and this is upon what you're calling. This is why shipgirls require a support infrastructure while you can build your own from basically nothing.
Anyway, to answer the question about the workshop...
Your assumptions is not completely inaccurate, but this "possession" can't be dissociated from the building process. That's why specific shipgirls can build some items and not others (Shamelessly making a game mechanisms into something plot relevant!). The apparition of fairies are actually just a byproduct of the construction process into which the shipgirl imprint a part of her to build the item. A destroyer wouldn't be able to create a 41cm gun for example.
For Abyssals, this is still the same, but they can cheat, and can call upon the abyss to transfer the necessaries experience to the item.
I summon thee,
@Bki ! Can we build more than one stuff at a time?
You can expand your base or your facilities, but only one at the same time. If the project will be finished during the week, you can start another immediately. If it take several weeks, then the project will continue until it is finished, or you decide to suspend it (in which case you can do another project while it is suspended).
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