Current explanation is that conscious sophont (biological) mind required for default jump transition.
Awareness is the requirement, at least sufficient enough to qualify as a reliable observer, in (I suppose) the von Neumann sense. Where this line exists in biological minds is hazy (I have this distinct recollection of reading an account of unsuccessful jump space experiments involving using lower animals as 'observers', but I cannot recall if this was anything canonical or not), but it can be said that Imperial technology (TL15) is unable to make artificial intelligences that are capable of satisfying this requirement.
That is, at least, until the Imperial Navy stumbled across that hack which conveniently allowed them to do it. But pretty much everyone in Charted Space wishes that they hadn't.
Not in the OTU, canon is clear.
Wait a minute ...
Kinunir, Annic Nova, Vampire Fleets, 101 robots
- Kinunir: According to the CT Adventure, the Kinunir did not show any indication of having jumped without any of her crew. I've never read the more recent novelization of what went down, but even if it contradicts this, the mitigating circumstances surrounding the ship (the experimental AI installation, and the fact that the malfunction happened in IY1088, see below) means that the above rule remains unaffected.
- Annic Nova: There is no evidence, anywhere in the text of the Annic Nova Adventure, that even implies that it was jumping without a crew. The ship is simply found, also adrift, with the crew missing and/or dead.
- Virus: The Vampire Fleet ships were capable of independent jump because they achieved full sentience, thanks to the above mentioned hack.
- 101 Robots: This, I do not know what you are getting at. Are you talking about the robots that went rogue and committed criminal acts, including hijacking starships? If so, then hijacking doesn't require one to go solo; lots of living beings can go along for that ride. In fact, since the robots didn't come equipped with Pilot skill, someone else would have to go along with them for that ride.
And, about this:
In CT, it was (S7, p9):
View attachment 3663
What
is, does not mean what always
was. Assuming the publication date of this supplement, autonomous XBoats would be a thing as of IY1105 or so. But CT canon also adds this salient point to the mix:
- CT Book 8 (Robots), Page 10: "Recently, the Imperium has started to experiment with combination courier-pilot robots as xboat pilots, but this is not common knowledge."
So, autonomous XBoats are possible
now, but they are a
recent and
experimental development.
So what, in the Traveller Universe, might have changed to allow this to happen? Why might starships prior to about IY1105 need crews to function in jump space, and those operating after IY1105 might, at least 'experimentally', not? I think we can already guess the answer.
According to
Survival Margin, the Deyo transponder chip (the one based on the Cymbeline life form) can achieve full awareness if it is connected to a sufficiently advanced processing network (like a starship computer).
This was the aforementioned hack which, while completely unintended, does allow for autonomous starships. The chips completed final testing in IY1086, and were implemented in
all Imperial starships from IY1088-1100.
As such, while
every Imperial (and near Imperial) ship built or operating after IY1100 was capable, under the right circumstances, of full autonomy, including jump,
no ships (outside of Ancients technology) operating prior to IY1088 could, or did.
Or at least I don't know of any examples of such in the literature. If anyone out there knows of any, I'd like to see it.