It's an old movie, sure, but I've been wondering if the ship is actually robotic or if it has an unseen pilot that speaks to David.
Great movie. A favorite of mine when I was younger. Yes, the ship is a completely robotic artificial intelligence. The only other biological creatures on board the ship are the various animals the ship has collected from various other worlds as part of its mission of exploration. The reason the ship didn't want to go back in time is that it feared that humans were not biologically strong enough to withstand the strains of time travel. The ship only eventually agrees to take David back because he was so sad at being stranded 8 years out of time without his family.
This is addressed directly in the film.
David: Yeah, So what do I call you, anyway?
Max: I am a Trimaxion drone ship from...
Since it's speaking directly to David, it's clear that it is the ship.