A United Airlines Boeing 767 flying from Rome to Newark diverted to Shannon Airport in Ireland after its crew reported vibrations from the right engine and an unusual odor aboard the aircraft.
United Flight 509 was crossing the Atlantic on Saturday, July 11, when the pilots changed course toward Ireland. The aircraft, Boeing 767-424ER registration N76065, was carrying 227 passengers and crew, according to multiple reports.
The flight had departed Rome Fiumicino Airport for Newark Liberty International Airport. Flight information cited by news outlets placed the aircraft at about 34,000 feet and roughly 280 nautical miles south of Shannon when the crew decided not to continue across the ocean.
Engine reduced to idle as the crew headed for Shannon
The crew reportedly told air traffic control that the right General Electric CF6 engine was vibrating and that an odor had been noticed aboard. The pilots reduced the affected engine to idle, descended to approximately 20,000 feet and continued toward Shannon.
Shannon is a major diversion point for transatlantic flights because of its long runway, emergency facilities and location on Ireland’s west coast. Airport fire and rescue crews were placed on standby before the United jet arrived.
Reports said the pilots also advised that the aircraft would be making an overweight landing. Long-haul jets can remain above their normal maximum landing weight when they return or divert relatively soon after departure, requiring crews and ground teams to take additional precautions.
Flight landed safely and all 227 people disembarked
The Boeing 767 landed safely on Shannon’s Runway 06 about an hour after leaving its cruising altitude. Emergency vehicles followed the aircraft and conducted a visual inspection before it taxied to the apron.
A United Airlines spokesperson later confirmed that the plane landed safely in Shannon to address an issue with one engine. The airline said everyone aboard disembarked without injury.
Passengers were provided with hotel accommodation, compensation and rebooking assistance, according to the airline statement reported by the Hindustan Times. The remaining Shannon-to-Newark portion of Flight 509 was cancelled.
What investigators and maintenance teams will examine
The precise source of the vibrations and odor has not been publicly identified. Maintenance personnel would be expected to inspect the engine and its associated systems before the aircraft could return to service.
An engine vibration indication does not automatically mean an engine has failed. However, an abnormal vibration combined with an odor gives a flight crew a clear reason to avoid continuing over a remote oceanic route and to land at a suitable airport.
The diversion ended safely, but the combination of a widebody jet, a reported engine problem and a mid-Atlantic course change makes the event a notable example of how crews manage developing technical problems conservatively.
Featured image: United Airlines Boeing 767-424ER N76065 approaching Washington Dulles in July 2025. Photo by Acroterion via Wikimedia Commons, licensed under CC BY-SA 4.0. File photo; not taken during the Shannon diversion.
