Interesting you mentioned a dragon, that was going to be my suggestion, a young red dragon supplying the “hot hair” as I seem to remember it you add more hot air to go up, and realease some from a valve to go down.
Of course if you have a captive red dragon as your hot air supply there is also a chance of Moma Dragon looking for her young.
Tinker Gnomes can really add to a campaign. One of my GMs had a Tinker Gnome air ship. It had some sor t of compustable feul that was leaking all over the place. It was launcehed by catapult and its landing gear was giantr springs. It was called the White Lightning XV, sadly we figured out what happened to 1-14 once we landed, but everyone survived.
