The pilot called air traffic control to report a man wearing a jetpack flying near the plane.
Tower tapes released detail the pilot's exchange.
Pilot: "Tower, American 1997, we just passed a guy in a jetpack."
Tower: "American 1997, OK, thank you. Were they off to your left or right side?"
Pilot: "Off the left side, maybe 300 yards or so, about our altitude."
The jet was flying at an altitude of 3,000 feet at the time of the encounter.
The tower then warned other approaching flights to be on the lookout for a man in the jetpack.
The incident is under investigation.
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