Fireworks require a careful process to ensure that they work optimally. There are several different kinds of fireworks but for this article we focus on the Orion Pirotehnika rocket firework, an aerial firework which launches into the sky. Also known as the skyrocket, the rocket firework was invented in the sixteenth century and involves a conical-shaped top to imitate a space rocket. True to form, it is often launched from the ground up and is often accompanied by a whistling noise as they take off.
Fireworks are ultimately explosives. They work like dynamite where you light a fuse and it explodes. Unlike other explosives and dynamite however, we enjoy fireworks for their splendour; the colour that they splash against the sky. The makeup of rockets, as fireworks, can be split into four main parts: the fuse, the interior, the shell.
So how are these fascinating holiday celebrative pyrotechnics created?
The fuse is called a visco fuse and it is made with an easily excitable material that carries the charge to the body of the rocket. This is the end bit that we light with a match or lighter; the catalyst for the entire chain of events to follow. The fuse is layered to have the outer coat water resistant to prevent moisture build up around the wick of the fuse.
There are a few contents inside the firework shell that make the firework work. There’s the mortar, the bursting charge and the propellant powder. Mortar, which is the outer container; the cannon the fuse is connected to. The shell (also known as the artillery shell) is the ‘housing’ surrounding the contents of the rocket firework. That’s the exterior we often see and hold while setting it up on the launch site. Of course, the colour and the sparkle is what attracts us. But what captivates us and makes us purchase the firework is the external design. This is an easy design printed on the outer layer of the rocket which is often paper, which while it does not hold any significance in the effectiveness of the rocket, is a pleasing aesthetic.
Inside the Shell
The contents of the shell are where the magic of fireworks lies. Inside the shell is the bursting charge, the propellant powder and the ‘stars’. The bursting charge in essence sets the explosion of the ‘stars’ once the firework has reached the required height. Propellant powder (or gunpowder) is what’s ignited when the fire reaches the end of the fuse and causes the firework to burst. The colour and sparkle of the firework display varies from firework to firework. So, some come with delay fuses to allow intermittent bursts as the firework launches. Different powder and chemicals give the colour that we see in the sky, too.