Dupe equiped with jet pack keeps flying away.

Jet packs are there for flying... Its your job to prevent them to go everywhere. Or to make sure, there is a way back, even if the bunker doors are shut. Yes i ran into the same problem. But thats easy to solve. I dont think this is a bug, but intended behavior.

Yup you are right it is not a bug. Basically I grant access to jet packs to dupes who delivery stuff; and these dupes always fly far far away to collect iron (fallen from the sky) and meat (killed by meteorite). I just don't think jet pack is "smart" enough.