Would it generally be considered safe to watch fireworks from a hot air balloon directly over or very near to the area where the fireworks are being detonated? What if the hot air balloon was up very high, out of the ‘firing range’ of the fireworks? Is there any good reason not to go up in a hot air balloon to watch fireworks like this?
FYI, I’m asking this on behalf of a friend. I personally think the idea is utter madness…but maybe I’m wrong.
We had a local television station cover this year’s fireworks from the ground as well as in the air (helicopter). The FAA informed them of their required minimum altitudes (it changed depending upon the distance from air zero). Many times the chopper flew directly over the the fireworks with the onboard cameras pointing straight down.
Granted, a helicopter is much more maneuverable than a hot air balloon.
Well, many locations which put on large fireworks displays (i.e. large cities) have tight air traffic control already. I imagine that whoever grants flight paths in these cities would not grant you one that goes anywhere near a dangerous flight space. It’s also likely that they would ground most flying objects as a precaution against people straying from the flight path, getting distracted and/or startled by the fireworks, etc…
In the small town I went to high school in, the city limited how close you could get to the fireworks by boat (they launched the fireworks over a lake) or by air. I can’t imagine how they would enforce the air ban without any aircraft of their own, but I would guess that any other municipality would have the same rules. I would also guess that they would stop the show if they saw an aircraft anywhere near the firing range.
So, no, I don’t think you could watch the fireworks from a balloon unless you were so far away that you would have no better view than you’d get anyway.
However, I’m not a pilot or other professional in fireworks or air travel. Keep asking.
mischievous
I can think of a couple of potential problems. One is that hot air balloons light up when the burner is ignited, which would be pretty, but would distract from the fireworks. So the people putting on the display might be annoyed.
More importantly, fireworks displays happen at night. Hot air balloons are not particularly manuverable and you pretty much take your landing spot as it comes. So trying to land a hot air balloon at night would be dicey at best, and in a built-up area with lots of powerlines, possibly suicidal.
It sounds like something that you would see in a Monty Python movie - or Blake Edwards. I’m seeing Jack Lemon as Professor Fate watching a rocket punch a hole in his own balloon (The Great Race). 
Good point there - hot air ballooning is almost always a daytime-only activity. I don’t know that it’s possible to get an IFR (instruments) rating for piloting a balloon. Or that anybody would put IFR instruments into a balloon. IIRC, balloons are more often considered a nuisance by air traffic control that they need to alert airplanes about.
Also, if you think about it, a fireworks display is designed as a 2-D presentation, meant to be viewed from the “broad side” on the ground. From above, the streaks in the sky as a rocket goes up would be more like points of light.
Aside from the problem of landing at night (which could be exceedingly dangerous), you have to remember that balloons are NOT very manuverable! You really are at the mercy of the wind, which may push you away from the fireworks - or into them. The only real control you have is vertical height. You could certainly get above the fireworks, but then you have the problem of getting back down.
More than municipal fireworks - which only rise a few hundred feet - I worry about model rocketry clubs which may have clearance to several thousand feet in altitude. The FAA does, by the way, require both prior notice for that sort of thing AND disseminates this information to pilots. You are given an altitude that they recommend you stay above to avoid problems, like errant balls of fire. This is fine for fixed wing and rotorcraft, which are quite manuverable, but again, balloons are not so steerable. If the wind fails the only way back down to the ground may be straight through the danger zone.
I’ve been in a hot air ballons with instrumentation like an altimeter, transponder, and radio stack, but the concept of “IFR” is a little strange - maybe for those record-setting round-the-world flights but your average hot air balloon would have nothing of the sort.
Most folks I’ve known who have watched fireworks from the air have said the show is actually much better on the ground - because that’s where they are supposed to be viewed from.