On December 4, Japan Airlines announced a possible cause and immediate recurrence prevention measures based on the trouble that the engine of a passenger plane of Japan Airlines was damaged and made an emergency landing at Naha Airport.
On December 4, Japan Airlines flight 904, Boeing 777, which took off from Naha Airport, returned to Naha Airport and made an emergency landing due to a problem with the engine on the left side being damaged.
The 189 passengers and crew were not injured, but the Japan Transport Safety Board is investigating it as a "serious incident" that could lead to an accident.
Japan Airlines commented, "We sincerely apologize for the inconvenience and inconvenience caused to our customers and related parties," and said that the cause was under investigation, and the possible causes and cases based on them. Announced measures to prevent recurrence for the time being.
Since it has been known that the blades inside the engine, which generate the propulsive force of the aircraft, have broken, some small damage has occurred to the fan blades, and fatigue failure gradually progresses from that point. It is said that there is a possibility that it went out.
Based on that possibility, the surface of the fan blade will be distorted, so as a measure to prevent recurrence for the time being, Japan Airlines will carry out a visual inspection every time it flies and specially invisible scratches. It is said that it will take more measures than the country requires, such as conducting an inspection with equipment once every 100 flights.