JTSB Serious Incident Report on JA8978
The Japan Transport Safety Board have completed their Aircraft Serious Incident Investigation Report (AI2022-5) on Japan Airlines Co Ltd flight JA8978
While a Boeing 777-200, registered JA8978 and operated by Japan Airlines Co., Ltd. as its scheduled flight 904, was climbing after take-off from Naha Airport for Tokyo International Airport on December 4, 2020, there occurred an abnormal sound accompanied by shaking of the Aircraft, and the instrument displayed anomaly in the left engine (No. 1 engine) at an altitude of FL170*1 over the sea approximately 50 km north of Naha Airport. The captain shut down the engine and landed back at the Airport after declaring a state of emergency to the air traffic controller.
The JTSB concludes that this was a serious incident certainly caused by the fan blades of the left engine which were fractured during take-off climb, resulting in parts and cowlings of the engine were departed, and the airframe was damaged by scattered parts.