Fireworks may be off the table this Independence Day in Durango, but the city is still celebrating in style this weekend with its first-ever drone show, which is scheduled to take to the air Saturday evening.

Drone show company Verge Aero contracted with the Durango Parks and Recreation Department to host a short but exhilarating aerial performance above the city at 10 p.m. The show will last only about 12 minutes, but it will be worth it, according to Verge Aero officials who organized the production.

For the most dazzling display, spectators are encouraged to watch the show from the Durango Transit Center, where music will play over speakers to accompany the production.

Chris Lutts, vice president of sales at Verge Aero, said Durangoans and visitors will be treated to something many of them have likely never seen. The city put up $30,000 to feature about 140 drones projecting images to a soundtrack as they fly in choreographed patterns 400 feet above ground.

“You’ll enjoy it, I promise,” he said. “Durango is a smaller community, kind of off the beaten path a bit. ... You’re (getting) stuff on the scale of what we’re doing in San Diego and Vail and Tahoe and Miami, Florida. It’s pretty cool.”

The drones are 12 inches by 12 inches and weigh just 2.75 pounds. They have four horizontal propellers, can fly at speeds of about 6 meters per second and are equipped with bright lights that shine at just under 1,000 lumens. By comparison, the beam from a 1,000-lumen flashlight can penetrate into the dark up to 200 meters, according to STKR Concepts, a lighting design company.

Lutts isn’t too worried about the chance of thunderstorms Saturday evening. Unless there’s a downpour, the drones should be able to weather the storms, he said.

Lutts said he likes to think of each drone as a little pixel in the sky. Verge Aero has put on shows with as many as 800 drones, or pixels, in the air at once, each one pre-programmed to fly in certain patterns around a fixed GPS location, combining the light they emit individually to create larger images.

He said when they set up for a show, they line drones in a grid, and then each drone operates within its own grid while in flight.

“When the show is designed, the software automatically calculates its position in space so that no drone ever intersects any other drone’s path,” he said. “They just know their own position for anti-collision and geo-fencing for safety.”

There are no remote controls, Lutts said. The whole show is computer programmed.

The city pursued a drone show this year because of drought conditions that presented prime opportunities for fires. Hazardous fire weather was abated a bit by the early start of the monsoon, which allowed fire restrictions to be downgraded.

But drones offer other benefits from the standpoint of safety.

Lutts said the drones are quieter than fireworks. Spectators won’t even hear the humming of propellers when the drones take to the skies.

Jared McCallion, a summer intern at Verge Aero, said fireworks are notorious for disturbing dogs and even triggering people who suffer from post-traumatic stress disorder.

“We did one (show) at a military base and it was big for PTSD,” Lutts said. “For folks that have these sensory things – you don’t have that ‘boom’ and ‘pow’ that can trigger something for an animal or for a person.”

Fire Marshal Karola Hanks said the Durango Fire Protection District reached out to other communities that have hosted drone shows to see what their main concerns or challenges were. The list of concerns was pretty small, she said.

The fire district will have a crew with fire extinguishers at the launch site at Greenmount Cemetery, she said. Fire officials have also screened the fly zone for electrical lines and other hazards, and they placed the fly zone in an area that won’t put the drones above any major roads.

One concern was charging all of the drones. They have short battery lives of about 14 minutes, and trying to charge them all at once presents a fire hazard if a proper charging area isn’t used, she said. The city will use the Exhibition Hall at La Plata County Fairgrounds as its charging station because it has ample ports and space, and electricians helped the fire department make sure the hall was good to go.

Another potential fire hazard is the lithium batteries that power the drones.

“Lithium batteries are known to generate heat and can be problematic in terms of fires and various things like that,” Hanks said. “So we have looked at that in terms of their safety protocol and their personnel that they’ll have on-site to watch for drones that may go rogue – which doesn’t happen that often.”

Her last concern is with somebody flying their own drone in the air space dedicated for the show.

“I really want to stress that deal: Folks, please allow us to present a good show for the community and keep your drones down,” she said.

Overall, drones are much safer than fireworks as far as Hanks is concerned. She said the drone show is an exciting prospect, but acknowledged the city is testing out new technology.

Some spectators may wonder what happens if two drones collide and hurtle toward the ground. Lutts said it isn’t a major concern thanks to very specific programming.

“We haven’t had a drone collide in a long time,” he said. “If one did and got out of bounds, they’ll get an auto land command.”

McCallion, who has a background in emergency management and disaster response, said the drones’ programming includes a formula that gauges wind speeds and height off the ground to calculate safety variables wherever it is flying.

He said a safety formula has been developed over countless test flights. After every mistake or accident or unforeseen condition, that information is taken into account and the programming is updated to prevent it from happening again.

“After you do that enough times you’re going to get virtually zero issues whenever you put on a show,” he said. “Of course, it’s never actually ‘zero.’ We can just assume, ‘OK, if this happens, we don’t want people standing in this radius.’”

The drones won’t fly directly over people, according to a city news release about the scheduled show.

Peter Smiatek, pilot and designer for Verge Aero, said choreographing and programming drone shows requires a filmmaking-like knack for storytelling.

“Storytelling: This is the most important thing in designing shows,” he said. “This is a brand-new industry. People really don’t know what’s possible. They really don’t know what they could expect.”

He said a creative mindset is key to designing great shows. He offered an example of a recent client he worked with who wanted the drones to depict strikes of lightning. The client gave Smiatek a basic drawing of lightning to illustrate the idea.

Smiatek said he took that idea and made it his own, using timed flashes from the left and then the right to simulate an epic thunderstorm. And the audience loved it, he said.

“But it depends on what audience we have,” he said. “If we have a company event, for example, and they want us to (display) company logos and brands, you can also do that. The transition between the shapes and the logos can also be very fascinating and animated.”

cburney@durangoherald.com