An emergency exit slide fell off a Delta Air Lines Boeing on Friday shortly after takeoff from New York.
Delta said the Boeing 767 pilots felt a vibration in the plane, circled back, and landed safely at JFK airport.
The United States Federal Aviation Administration (FAA) is investigating the latest incident involving a Boeing aircraft.
Plane returned to JFK without further incident
"As nothing is more important than the safety of our customers and people, Delta flight crews enacted their extensive training and followed procedures to return to JFK," the airline said.
There were 176 passengers, two pilots, and five flight attendants on board the flight, which was scheduled to fly to Los Angeles.
They declared an emergency so the flight could be routed quickly back to JFK airport.
Boeing has faced increased scrutiny over plane safety after a door plug blew out of a 737 Max during an Alaska Airlines flight in January. Its not clear what caused the latest incident.
The plane is now out of service and is being evaluated.