Update: There is now a wiki entry for jumpdrives, which supercedes this.
When ships are close enough to each other in voidspace, their jump fields will interact slightly. Enough to notice at most range, but a larger field can knock a smaller field out of whack at close range, enough to "swamp" it: collapse its jump bubble. If it's got a solid jump charge, the bubble can be re-lit, but in the meantime it will coast to a stop, making it vulnerable to boarding. If the jump field isn't restored while the ship is in deep voidspace, it will drop out - whether this means it is destroyed is unclear, but it is never seen again.
As the jump charge decays, the window to restore the jump field drops from 6-8 hours down to as low as a few minutes. Swamping a ship that's within the correspondence area of a solar system can force it to drop out into realspace before it has arrived at its destination.
Conversely, a ship that has its running lights off and its jump bubble down is all but invisible (except when silhouetted against something else) in voidspace. Of course, it can't move, and it can't stay that way for long without dropping out (and with a jump charge that's too high, that is generally unsafe), so a pirate hoping to knock an inbound freighter into realspace prematurely has to calculate carefully, and generally know the freighter's course well in advance.
Observation points
Update: There is now a wiki entry for jumpdrives, which supercedes this.
If a key part of a ship's "instruments" is the eyes of its biological crew, a ship has to have windows, which is kind of atypical.
I know I've mentioned starships with rivets, but I think I've also talked myself into starships with portholes.
Before the mast
Still more Moby Dickery:
Now, the grand distinction drawn between officer and man at sea, is this—the first lives aft, the last forward.
This probably doesn't mean much among smaller-crewed ships, but it does for naval and larger (more naval-esque) ships: there are two (or more) separate crew areas. In Trav deck plans, and therefore in mine, the "officers" tend to live forward, adjacent to the bridge. (As the captain would be adjacent to the tiller/wheel, maybe?)
Some of my ships have crew cabins next to the bridge and engineering, but that's more convenience than social strata.
the community of interest prevailing among a company, all of whom, high or low, depend for their profits, not upon fixed wages, but upon their common luck, together with their common vigilance, intrepidity, and hard work; though all these things do in some cases tend to beget a less rigorous discipline than in merchantmen generally
The smaller tramp freighters, I think, probably are paid in shares in the same way as whalers were.
Jumpspace navigation, yet again
Update: There is now a wiki entry for jumpdrives, which supercedes this.
What if: currents and realspace correspondences can be picked up by their effect on the jump field, but the former, at least, is not wholly predictable. As in: you know you're being swept "sideways" by the current, but not necessarily how much exactly.
But also: if you know your correspondence to realspace, you know what direction the other gates are, even if you can't see them, which eliminates my problem of "you can see distant stars even if you can't get there."
I think I'm going to go with this. You still need to take sightings, either looking for the false star (when you're close enough), or perhaps taking soundings of the currents. A ship could send out a flare of brightspace energy, which can't be picked up by instruments, and see where it ends up. This would probably be better for choosing an efficient path than for navigation as such, but it would make human-piloted ships faster than bot ships even if the latter could fly entirely by the jump field effect.
The Advocate
Chapter 24 of Moby Dick is all about the influence whaling had on the world of its time and tbh I am starting to rethink the whole idea of combers and so forth. Maybe deep-sea fishing is the way to go? Whaling would, of course, be controversial, since there's clearly a higher order of void creatures, the equivalent of whales and dolphins.
There's still no three-year whaling voyage, unless I assume some part of the map where the gates only lead to deep-space locations on the realspace side or something. Hmm.
Space weather
I have established that jumpspace has "weather" but not exactly what it is. "Currents" might be more like it. I think that should be something you can detect with the jump field, which will give engineers more to do during jump. The general underlying currents can be mapped and known (star charts!) but they can shift over time, and short-term eddies can spring up. Too much turbulence can deform or even snuff out a jump field, so pilots will want to skirt "storms" where they can.
Within a false star, there's a bit more turbulence so it's somewhat more hazardous. If it's not the presence of the gate but rather the echo of the real-world matter, causing it, it could be that a ship could navigate by the presence of their destination planet's "wake" in jumpspace. Hmm.
Whaling, again
I've been (re)reading Moby Dick as part of a book club, and I am not entirely happy with the combers/voidwhale situation. So I think I'm making some more changes: given the correspondence of realspace to voidspace around a false star, interstellar flights don't begin/end inside the false star. Diving into the star (which, again, is a dense area of mostly-small not-exactly-energy creatures) is a little more hazardous, so combers are not just big vacuum cleaners. Or, they are but there are things you don't want to vacuum up. And individual ships can collect bright energy as well, but without the specialized fields of a comber they have to go for bigger prey.
On a slightly different note: in Traveller you get a loan from a bank and buy your starship like you're buying a car. But of the Pequod:
It turned out to be Captain Bildad, who along with Captain Peleg was one of the largest owners of the vessel; the other shares, as is sometimes the case in these ports, being held by a crowd of old annuitants; widows, fatherless children, and chancery wards; each owning about the value of a timber head, or a foot of plank, or a nail or two in the ship. People in Nantucket invest their money in whaling vessels, the same way that you do yours in approved state stocks bringing in good interest.
I think I like this idea, and certainly this is the way Zhdez ships are "owned": a co-op.
