I have unfortunately not had the opportunity to see these Hanabi Shells for real.
But on the movies I find very bad qualities this 24inch japanese shells
from Berlin. They are very short in effect duration, altitude is low, the colors
are not really beautiful, and the explosion of the shells too powerful that
distorts the visual sphere.
I feel that the burden of propulsion was too low and the explosive charge far too high!
Or mortar can be too short ... The use of fiberglass may also be the
cause may be that this material absorbs too much energy, I really do not know ...
Because mortars are usually a little longer and steel. This is the first time that
I see 24 inches of Fiberglass Mortar tube
In 1994, I attended in France in the firing of 2 x 24 inches shell by Lacroix-Ruggieri (I believe that came from Shells Marutamaya, Ruggieri worked much with them at this time)
These shots were for the opening ceremony of the Shuttle Tunnel (France > GB) on beaches of Calais (Fr).
I was very young, but I remember that they reached an altitude very
high (since one of the 2 shells had exploded above the clouds), but I
recall very well that I've seen, high altitude, although round, visual effect
very long, a lot of sound, very loud, color, and small spin incandescent during very long minutes after the shooting.
Maybe it was made in France (no Hanabi), I know not ... But it
much like the shell fired at Berlin in 1987.
However, I found very interesting the display of PyroArt.