Ads for 1978's "Superman: The Movie" proclaimed "You'll believe a man can fly." This past weekend, a very different kind of promotion for a new superhero film actually did convince some New Yorkers that human beings had taken to the skies.

What looked to be three people were spotted flying around the skies of lower Manhattan last Friday, causing a lot of double-takes and dropped jaws from onlookers. But while it appeared to be a sight straight out of a comic book, it was actually a clever bit of viral marketing for this week's upcoming film "Chronicle." Those aren't people in the air, but some very intricately designed radio-controlled airplanes. Watch the video of their flight, and keep reading to learn how it was done.

The movie tells the story of three high school students who discover they have superpowers, including the ability to fly. To promote it, the studio called on Thinkmodo, a company that specializes in creating viral sensations. They first made a splash with a video that seemed to show a man using an invention to hack into the video screens in Times Square. It was later revealed to be a tie-in for the Bradley Cooper movie "Limitless," which went on to be a surprise hit. For "Chronicle," though, the team had a different direction in mind.

Related: Buzzy Viral Video Actually a Promotion for 'Limitless' >>

I interviewed James Percelay, the co-founder of Thinkmodo, over email about the video. He said he and his partner Michael Krivicka were approached by 20th Century Fox, the studio behind "Chronicle," and they hatched a plan to do a live event they would also film for a viral video. Percelay said they received approval for the project just three weeks ago. They employed model airplane builders in Oregon, Pennsylvania, and New York to build the three featured planes and two back-ups.

Percelay said, "The planes are highly sophisticated dacron/carbon fiber, battery-powered, radio-controlled units," each with over 200 parts. Percelay described the individual pieces as being "light and delicate as potato chips." Their "flying people" are six feet tall, but they weigh only four pounds. The aircraft were all built in a week, half the time it would normally take to construct them.

Percelay wouldn't reveal exactly who was piloting the planes in the video, only to say "[They] are expert AMA (Academy of Model Aeronautics) members with amazing skills." They practiced flying for two days in Long Island before taking them out for a spin in New York. According to the Los Angeles Times, the three people-planes made six trips over the Hudson River, each lasting only five minutes due to the short lives of their batteries. One flyer did take a tumble into the river and had to be fished out by the NYC Harbor Patrol.

Watch new clips from 'Chronicle' >>

Unlike the "Limitless" video, where the promotional aspect was hidden until the viral element has spread across the Internet, the "Chronicle" stunt actually shows how it was done. Percelay said the Thinkmodo team felt "the behind-the-scenes aspect of this video was even cooler than trying to create a hoax." In an age when we assume everything we see has been digitally manipulated in one way or another, it is especially impressive to watch real aircraft being piloted to such an amazing effect.

Percelay said that the spectators in New York -- notoriously a hard-to-impress bunch -- were uniformly astounded by the flying people. He said, "We loved that nobody felt threatened by them since their movements were so life-like and graceful... A number of people said it looked like an 'aerial ballet.'"

"Chronicle," the movie that inspired the stunt, opens this Friday. Watch the trailer below.

See more at Yahoo! Movies >>