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The Rocket’s Red Glare
July 11, 1999

Fireworks 2

July 4th, Independence Day, is the day every American fireworks fan dreams of… starbursts light up the night sky, flowers of light blossom in the twilight, brilliant displays enthrall the eye, while children of all ages are captivated by the spectacle. But have you ever wondered just how the magic happens?

Masters of Fire and Light

Phil Grucci, Vice President for Design and Operations for world-famous fireworks manufacturer Fireworks by Grucci , knows the lure of pyrotechnics. The fireworks master says his fascination with pyrotechnics has lasted "all my life, since I was five years old with my father going out on a barge in Coney Island."

The Grucci family has been creating fireworks displays for 150 years, and has pioneered many of today’s hottest innovations, incorporating digital technology and chemical artistry to create ever more dazzling displays of fire and light. But one facet of the fireworks art has not changed: each charge is hand-crafted, taking up to one and one-half weeks to make.

Getting a Charge Out of Fireworks

image: Fireworks by Grucci

The heart of each charge, called a shell, is a hollow cardboard and papier-mache sphere packed with small pellets of specially formulated chemicals called stars. The star is composed of a doughy substance blended with the elements and chemical salts that give the charge its brilliant colors.

Some salts used to produce the colors are strontium (reds), copper (blues and greens), and magnesium (white). Metals such as aluminum (white) and iron (golds) produce the twinkles. The various chemicals can be combined virtually infinitely to create a rainbow of effects.

"When we layer the powder onto a ball, if we want the star when it burns to go from red to green to white, the first layer is white, the second layer is green, the third layer is red and when that burns, it burns from the outside to the center," Grucci explains.

"About a thousand of those small stars… would be in a six-inch in diameter shell casing," Grucci says. Black powder, sparked by fuses, provides the propulsion for the charges. The black powder and fuse container is molded to the bottom of the shell.

At the display site, the shells are loaded into mortars—pieces of pipe sealed at one end. Then, a wire attached to the fuse is threaded into the firing system, and electric sparks ignite the fuse.

Another fuse inside the shell acts like a timer. "It burns for about 4 seconds," Grucci says. "The timing mechanism ignites everything on the inside and then breaks the case open." Then, "whatever… was loaded in the shell back at the plant will take its fiery effect."

Those effects include everything from stars and Grucci’s signature golden split comet to companies’ names and phrases spelled out, to New Year’s Eve countdowns exploding in the sky.

Blast from the Past

As Grucci tells it, the Chinese discovered fireworks accidentally nearly 2000 years ago, and developed them for the purpose of warding off evil spirits. They found that by mixing saltpeter, charcoal and nitrate, the components of gunpowder, they could make a huge bang, which scared off the demons.

"In the beginning, fireworks were only white and yellow, which is what black powder produces," Grucci says. Over the centuries, Europeans found that adding metals and chemicals created many more colors.

Over the last 200 years, as fireworks became a form of entertainment and celebration, the art of pyrotechnics has been supplemented and refined by science:

  • Chemistry: Fireworks masters can now produce all hues of the rainbow, and even produce company logos in fire.
  • Physics: Pyrotechnicians use their expert knowledge of explosives to calculate and orchestrate ever more complicated geometries. One of Grucci’s latest creations displays a rainbow of colors in an arcing rainbow pattern.
  • Technology: Electronic fuses, controlled by computers, make the sequencing of fireworks displays easy; computers also coordinate musical programs to the pyrotechnic show. Even today, however, many fireworks displays are fired manually.
  • Safety: Grucci says that with advances in chemistry, "you can manufacture fireworks to be placed on a table ten feet away from the audience…and you’re able to do that safely indoors with low smoke." Also, deaths from fireworks accidents have declined in recent years.

Grucci points out that there is still only one sure-fire way to test the finished product, adding that the plant’s neighbors think it’s a blast. "We manufacture what we’re testing right here on this property, so our surrounding community enjoys it, "Grucci says. "When we do our testing… they get their firework show once a week."

Thinking Big

Like most pyrotechnicians, when asked about his future goal, Grucci thinks big. "Back in 1979, we manufactured a 42 inch in diameter shell and we broke the world record and we were introduced into the Guinness Book of World Records," Grucci says. "Since then it’s been broken and now the new target is 52 inches in diameter. That would be our next challenge to begin working on.

Y2K Will Be a Bang

Grucci promises some new items for this Fourth of July. However, next year promises to eclipse all others in bedazzlement.

The Grucci firm is booked over 12 time zones for the year 2000. "There’ll be surprises in each and every one of those programs to the extent of the musical selections as well as the pyrotechnic devices designed for the millenium," Grucci says.

Elsewhere on the Web

What are some of the advances in fireworks technology? (STN2 Q&A)

Pyrotechnics’ Guild International, Inc.

Fireworks by Grucci

Chemist Petri Pihko’s site: Pyrotechnics—The Art of Fire

600 milliseconds in the life of a shell

Nova Online’s Kaboom! site

American Pyrotechnic Association

by Debra Utacia Krol

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