Greetings,

I was just curious. Does anyone know how some particular fireworks create certain images?

What I mean are things like those smiling faces that look like this:

Also, they're other fireworks that project other shapes as well, such as clover leaves or hearts and even blue stars.

This leads to another question. What causes those sparkling rocket type fireworks to go up and then come back down and then go up again and come back down once more?

Please reply soon.

Regards,

Trav.

What I mean are things like those smiling faces that look like this:

Also, they're other fireworks that project other shapes as well, such as clover leaves or hearts and even blue stars.

This leads to another question. What causes those sparkling rocket type fireworks to go up and then come back down and then go up again and come back down once more?

That's good idea.

I've seen very simple shapes projected by display shells in fireworks stadium: red heart, fish, tie,five pointed red star,star&moon,four petal,ect. And some I don't know.

As for that rocket, it is hard to do it.

Yes, I know how complex and fascinating they are, but still, I would like to know how they're done.

It's interesting to know.

Regards,

Trav.

Your question relates to some fireworks technic. It is hard to answer you.

I'm sure it's a very complex technique, indeed. I just wonder how they do it.

It fascinates me in the way they're projected before the audience. I find it incredible when I'm viewing these particular fireworks, let alone the audience.

Trav.

It's not as complex as it might sound. This "rockets that go up and down" are called double ascension girandolas. A girondola is simply a small wheel with a number of drivers (which are somewhere between fountains and rockets in how they operate) set almost perpendicular to the rim of the wheel. Because they are not quite vertical, they cause the wheel to rotate around its pivot. The vertical thrust , though, is enough to lift the spinning wheel into the air. To get the double ascension affect, simply two sets of drivers are used. After the first set burn out, the wheel starts to fall before the second set of drivers fires-up. Then the thrust is enough to cause it to start to rise again. It is the gyroscopic action of the spinning of the wheel which causes the (fairly) stable trajectory.

Hope this helps explain how this very enjoyable effect works.

Paul.

Thank you Paul.

Your explanation is clear and concise and it helps me understand this effect much better. I really had no idea of how that was done. Anyways, thx.

One more question. How do they cause certain fireworks to become into particular shapes? For example, the smiling faces, the hearts, the triple rings, blue stars, etc.

How is it done?

Regards,

Trav.