LOS ANGELES - It was an otherwise quiet Sunday night at the Los Angeles International Airport control tower when an American Airlines pilot radioed in with an unbelievable report.
"Tower, American 1997. We just passed a guy in a jet pack," the pilot said.
Minutes later came another report, this time from a pilot approaching LAX in a Jet Blue airliner: "We just saw the guy pass us by in the jet pack."
So began one of the most intriguing aviation mysteries Los Angeles has confronted in years.
Those sightings occurred Aug. 30. The case took another twist Wednesday when a China Airlines pilot approaching LAX reported seeing a jet pack flying at an altitude of 6,000 feet. That's more than a mile up.
The FBI is on the case, as is a good chunk of L.A.'s aviation community, which has been buzzing about the sightings.
Although jet packs make frequent appearances in popular culture and movies - think Sean Connery's James Bond and Disney's "The Rocketeer" - they are actually very rare.
There are only a handful of companies around the world that make jet packs, including a winged device created by former Swiss air force pilot Yves Rossy, which requires him to be hoisted in the air by a helicopter or balloon before he can take off. There is also a type of hoverboard made by French company Zapata and flown only by its inventor, Franky Zapata.
Locally, Chatsworth-based JetPack Aviation has created five jet packs that are worn like backpacks. But they're not for sale, and Chief Executive David Mayman said none of his competitors' products are sold to consumers, either.
It's possible that Wednesday's sighting near LAX was indeed a person flying with a jet pack. But the reported altitude makes such a flight seem "highly unlikely," said Mike Hirschberg, executive director of the Vertical Flight Society, a nonprofit professional organization.
Mayman said his company's jet packs are technically capable of soaring to heights of 15,000 feet. But because of fuel constraints, they can actually reach only about 1,000 or 1,500 feet off the ground safely.
"To fly up to 6,000 feet from the ground, to fly around long enough to be seen by China Airlines and then to descend again, you'd be out of fuel," he said.
Mayman said he knows it wasn't any of his company's jet packs because he knows exactly where they are - plus, they are disabled when not in use, so grabbing a pack out of storage wouldn't be possible.
Instead, he suggests a more likely scenario, an electric drone - perhaps with a mannequin attached.
Thomas Anthony, director of the University of Southern California Aviation Safety and Security Program and a former Federal Aviation Administration criminal investigator, said the strongest evidence that the LAX sightings is a person with a jet pack - as opposed to a balloon or drone - came from the American Airlines pilot, who reported seeing the object at 3,000 feet over Cudahy.
The pilot stated he saw "a guy in a jet pack" 300 yards to his left and flying at about the plane's altitude.
"That is quite close," Anthony said.
He said federal investigators would immediately look at the limited number of jet packs that exist in the U.S. and overseas.
"People in that community will know who has bought these packs," he said. "If someone is doing this, they are going to have to take off and land somewhere, and there is going to be noise."
Anthony said he doubts the culprit is using an airport to take off and that investigators should look to out-of-the-way industrial spots for clues. The FBI suggested the jet pack was flying in a section of Southeast Los Angeles County near Cudahy and Vernon that is dotted with commercial and manufacturing businesses.
The flying range of jet packs is pretty limited, Anthony added, so it's unlikely it traveled any great distance.
After the China Airlines pilot's report Wednesday, the LAX control tower called in a law enforcement aircraft to investigate.
The aircraft was flying about seven miles from where the pilot said he'd seen the jetpack, according to radio communications.
But when the craft arrived, no signs of the jet pack remained.
A jet pack could be operated as an ultralight - meaning it would not be registered and its operator wouldn't need a pilot's license if it meets fuel capacity, weight and speed requirements, according to the FAA. Ultralight aircraft are permitted to fly only during the day and are barred from flying over densely populated areas or in controlled aerospace without FAA approval.
Anthony and others say it's imperative that the FBI investigate the sightings for safety.
"This does represent a very significant compromise of the airspace," he said.
If a rogue pilot were flying at 6,000 feet without a transponder or radio, Anthony said, that would put him or her in the path of commercial airlines maneuvering over Los Angeles.
Airliners are designed to withstand getting hit by small objects. But a big metal object is another matter, especially if it were sucked into an engine.
"The engines aren't designed to consume something large and metal, or something with fuel that's going to burn or explode," Hirschberg said. "That could be potentially catastrophic for an airplane. You could potentially have an engine explode and bring down the airliner and potentially hundreds of people could die."
So is what has been reported near LAX really a jet pack?
Some experts say it's possible.
In February, a pilot in Dubai reached an altitude of 5,900 feet flying a Jetman jet pack powered by four mini jet engines with carbon-fiber wings. The pack's builders say it can reach speeds of nearly 250 mph. After a number of dip and roll maneuvers, the Dubai pilot descended to the ground using a parachute.
Others, though, are more skeptical. Hirschberg said the apparatus seen near LAX could have been a balloon, particularly because the China Airlines pilot noted that the flying object was shiny.
Or it could have been a drone, he said. In recent years, some airports have had to halt flights after drone sightings. In 2018, London's Gatwick Airport closed for more than a day after repeated drone sightings.
Drones comes in many shapes and sizes. In August 2019, an inventor demonstrated a flying man drone at a German remote control show. The drone was made to look human with a flight suit stuffed with bubble wrap with boots and a lightweight visored helmet attached to a battery-powered drone.
In the U.S., recreational users are not allowed to fly their drones higher than 400 feet, cannot fly over people or moving vehicles and are prohibited from interfering with crewed aircraft.
L.A. airspace is no stranger to unexpected sights. Back in 1982 a guy took flight over Long Beach in a lawn chair lifted aloft by helium-filled balloons. Pilots reported seeing him too.
As for the jet pack sightings, the FBI has so far been tight-lipped about its investigation.
But on the late August night when the mystery began, the air traffic controller summed up the feelings of many: "Only in L.A."
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