The first pilot report of a person flying a jet pack high over Los Angeles was enough to start a federal investigation. The second caused a stir on airport channels, with an air traffic controller remarking, “Only in LA.” Months after that, a controller warned, “The jet pack guy is back.”

The authorities now say the jet pack guy may in fact be more of a balloon guy.

“One working theory is that pilots might have seen balloons,” Rick Breitenfeldt, a Federal Aviation Administration spokesperson, said Wednesday.

The FAA made its statement after NBC 4 News in Los Angeles on Monday published police video and photos showing what appeared to be an inflatable, life-size or larger-than-life-size balloon in the shape of a person floating above the Beverly Hills and Holmby Hills areas. The station observed that it looked like Jack Skellington, the spindly looking and sharply dressed main character from Tim Burton’s 1993 film “The Nightmare Before Christmas.”

The images were captured by a Los Angeles Police helicopter crew in November 2020, about two weeks after a second jet pack sighting, and around Halloween, the station said.

“The FAA has worked closely with the FBI to investigate every reported jet pack sighting,” Breitenfeldt said. “So far, none of these sightings have been verified.”

The Los Angeles Police Department declined to comment, saying that the investigation was being run by the FAA. and the FBI. The FBI did not immediately return a request for comment.

Retailers sell a variety of decorations and toys modeled after Skellington, or at least resembling the character, including a 6-foot hanging model and an 18-foot inflatable model.

Pilots first reported a suspicious sighting in August 2020, describing a man flying a jet pack at about 3,000 feet near Los Angeles International Airport. “Tower, American 1997 — we just passed a guy in a jet pack,” the pilot of American Airlines Flight 1997 from Philadelphia told air traffic control at the time, saying it looked like there was a person about 300 yards to the plane’s left.

The sighting started an investigation by the FBI and the FAA. The authorities then heard of a second sighting about six weeks later, as crew members on a commercial airliner flying near the airport reported seeing what looked like a person at an estimated 6,000 feet. This July, a third sighting, at 5,000 feet, was reported by a pilot flying a Boeing 747 over Los Angeles.

“Possible jet pack man in sight,” the pilot said at the time. After air traffic controllers and pilots discussed the sighting, a pilot simply said, “We’re looking for the Iron Man.”

A spokesperson for the FBI at the time of the third sighting said that the bureau was working with the FAA to investigate, but that it had not been able to validate any of the previous sightings.

While the jet pack sightings have drawn widespread attention, they’ve also drawn skepticism from companies that make jet packs.

Most jet packs lack the fuel efficiency to fly for more than a few minutes, which makes it difficult for them to get very high. And flying in a crowded airspace, like around a major airport, could be extremely dangerous for a jet pack user, who would risk collision with a jet or being drawn into a plane’s engine.

The FAA has tried to reduce the risk of accidents with aerial vehicles like drones in recent years, enacting new rules and restrictions. The agency requires authorization to fly drones in controlled airspace.

Despite the hazards of handling jet packs, some companies, inventors and stunt-takers have pursued them. In 2020, a pilot from Jetman Dubai, a team of pilots who says it is “pushing the boundaries of aviation,” flew nearly 6,000 feet up using a jet pack, in a flight that lasted 3 minutes. The landing was aided by a parachute. Last year, the team said that one of its pilots, Vincent Reffet, died “during training in Dubai.”

Some tourism companies also offer the opportunity to fly jet packs, usually for just a few minutes at a time and over areas of water.

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