Though it is not recommended for amateur firework enthusiasts to partake in the use of aerial shells at their wedding, on the 4th of July, or at other types of events without adequate training from an approved licensing facility, many people are still curious about the science behind how an aerial shell works. Whether you’ve always wondered from the first time you saw a big city fireworks show or you’re planning on hiring a professional pyro technician to put on a show at your wedding or private event, aerial fireworks shells have always been a point of awe and fascination.
The first thing to note is that aerial shells come in a wide variety of shapes, sizes, and effects for viewers to enjoy. If you’ve ever been to your local fireworks store, then you’ve probably already seen the standard consumer sized aerial shells that can be purchased without a special license. These shells are usually 1 ¾ inches in diameter and reach heights of between 50 and 75 feet before they explode in the air. Though these are the smallest aerial shells you can buy and are typically available without any special training, you shouldn’t confuse that fact with them being completely safe to use. You take very careful precautions when using aerial shells and should definitely consider choosing smaller fireworks like fountains and sparklers for your backyard celebrations.
The second type of aerial shells that are available are considered professional grade. You can’t easily find them for purchase, even with the proper licensing and training, because most professional pyro technicians make their aerial shells by hand in their own factory. Professional aerial shells range in size from 3 inches in diameter to over 24 inches in diameter depending on the size of the fireworks show, but most professional aerial shells are between 6 inches and 12 inches. The science behind an aerial shell is essentially the same regardless of how big the shell is, you will just need more lift charge for a bigger shell and the explosion will be much more impressive in the air.
The Anatomy of an Aerial Shell
A simple aerial shell consists of 4 parts; the lift charge, bursting charge, black powder, and the effect. We’ll take a look at each part in detail to give you a better understanding of how aerial shells work.
The first part is the lifting charge which propels the aerial shell into the air. This portion is located underneath the actual shell and the amount of powder used is determined by how heavy the shell is, how much resistance it will face going up, and how high you want it to go before it explodes.
The second part is the bursting charge which does exactly what it sounds like it will do; it causes the aerial shell to burst apart. This is timed to go off at the appropriate time so the shell explodes when it reaches the highest point in the air that the lifting charge was designed to elevate the aerial shell.
Next, you have the black powder which is essentially filler that pushes the effect charges away from each other. When the bursting charge goes off, it ignites the black powder to both ignite the effect charges and cause them to go in several directions.
Lastly, you have the effect charges that come in a wide variety of shapes and colors. This is essentially what you see when the aerial shell goes off. They come in shapes like willows, stars, and flowers, but the process is essentially the same for any variety of aerial shell.