NPR ships vanishing?

[formicae (OP)]

In my first game with actual spacefaring NPRs, I'm seeing some AI behavior that I'm having trouble understanding.

We made first contact when they came into Sol, and every few months or so they'll send a ship in to visit Earth.  They'll just sit there (either next to my Luna colony or 10,000 km off Earth) for about half a day of 60-second increments, without either of us being the first to shoot, and then vanish.  Based on my passive and active sensors, the only way I can think of that they could have left without me seeing them leave is if they managed to make the normally-several-day journey to and through a JP within 60 seconds, so the only thing I can think of that they're doing in game-mechanics terms is that they're deleting their ship.

Is there anything else they might be doing, and if they are sending in ships and deleting them, is that a bug?

[AL]

What are the detection ranges of your passives/actives? Could it just be that the NPR ship left your sensor range within one increment and so they disappeared from your display?

[formicae (OP)]

Well, the AI began behaving more reasonably (visiting Earth and then leaving) after I restarted the game (tangential question: is it necessary to quit to copy the DB and get a clean save file, or can I just copy Stevefire. mdb while Aurora is running?), so I'm leaning towards guessing that this was a bug.

But my passives had been tracking it from outside Saturn's orbit (that was EM; I'm doing some rough math and I think I'd have had at least about 50m km range on thermals), my actives (the R1 ones I had on) had a range of 7. 6m km, and I saw it at less than 2000 km/s (I've since learned from espionage that they're using nuclear pulse engines).

[Erik L]

As long as you are not actively writing to the database, you should be able to copy it. Look at the Aurora backup utility in the Installs forum. And I think the portable wrapper copies it also.