That's gung-ho! Making your own hydrogen with zinc and HCl is way more dangerous than getting a cylinder of gas.
When I've built hot air balloons, we've chased them for over an hour, retrieved, refilled, relit and relaunched them!
Some of them covered over 80km in a single flight.
As I mentioned in another thread I've been working on a tiny glider controlled with an Arduino.
Now I live in the city again I've had to stop development for a while, that and summer/fire ban season is here again.
But next winter...