A United Airlines flight from Frankfurt, Germany to Houston, Texas was forced to turn around.
According to FlightAware, the United 47 made a U-turn over Great Britain on Tuesday.
A spokesperson for United said the Boeing 777-200 experienced a mechanical issue and was diverted back to Frankfurt Airport.
The plane safely landed just before 5 p.m.
"We have made arrangements to get customers to their final destination as soon as possible via other routes," United said.
United did not specify what type of mechanical issue the plane experienced or how long it would be out of service.