Fireworks go up to 1500 feet in the air. The littler ones go a few
hundred feet up, but the big displays can send an occasional one up a
thousand feet. The burst from the bigger ones is several hundred feet
across (thus my statement that you are unlikely to find anything above
1500). I flew over the Macy's display some (koff) years back and was
above them (but not by much) while below the class B.
They are indeed more specatcular from the ground, up close. However,
they are interesting from the air inasmuch as the aircraft's motion
changes the perspective on the burst as it is exploding, which is a neat
effect and worth flying to see. It's also fun to see the displays all
over the land as you are flying around.
You may not get what you pay for, but you sure as hell pay for what you get.
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