The FBI is investigating following the sighting from two pilots on separate flights near Los Angeles International Airport on Sunday.
Several US media outlets obtained a recording of communications between the pilots and air traffic control, which revealed details of the incident.
In the recording, one pilot says: "Tower, American 1997. We just passed a guy in a jet pack."
The controller responds: "America 1997, okay - were they off to your left side or right side?"
A few seconds later, another pilot tells the tower: "We just saw the guy pass by us in a jet pack."
The controller then urges the pilot of a JetBlue flight to "use caution", adding: "Person in a jet pack reported 300 yards south of the LA final at about 3,000ft."
An unidentified person then says: "Only in LA."
America's aviation regulator, the Federal Aviation Administration (FAA), confirmed the sighting.
In a statement to NBC News, it said: "Two airline flight crews reported seeing what appeared to be someone in a jet pack as they were on their final approaches to LAX around 6.35pm (local time) [on] Sunday.
"The FAA alerted local law enforcement to the reports, and is looking into these reports."
The FBI's Los Angeles Field Office also confirmed it was aware of the sighting and is investigating, NBC News reported.
https://news.sky.com/story/pilots-report-seeing-guy-in-a-jet-pack-at-3-000ft-above-los-angeles-12061418
