Holy shit, it was controlling itself? Why are we even letting these things do missions for us? Sure, they are safer, but if they could potentially control themselves, and fuck shit up in places they shouldn't, I say we just off the entire project.
As a poster above me noted, the way that these bad boys work is by satellite connection; if that satellite connection cuts out for a second, the vehicle just keeps going on the course it previously had set (if it shut down every time the connection was interrupted, we'd be losing lots of Reapers). So no, it wasn't thinking for itself; basically, it went on autopilot and kept flying. The only issue is that it wasn't supposed to be flying into the area it was headed in to, that's all.
People need to actually read articles instead of assuming things.