The Aviation Safety Council (ASC) releases final report on investigation of a EVA Airways flight BR56, while the aircraft were passing through Fukuoka, Japan, at altitude of 31,000 feet, encountered turbulence.

On November 22, 2017, EVA Airways passengers flight number 56, aircraft model B777-300ER, registration number B-16718, took off from Taoyuan International Airport to O'Hare International Airport, the United States. There were 3 flight crew members and 15 cabin crew members with 181 passengers, 199 in total on board. While the aircraft were passing through Fukuoka, Japan, at altitude of 31,000 feet, encountered turbulence and 3 passengers and 8 cabin crew members suffered injuries, and the aircraft had no damage.

According to the Republic of China (ROC) Aviation Occurrence Investigation Act, and the content of Annex 13 to the Convention on International Civil Aviation, the Aviation Safety Council (ASC), an independent aviation occurrence investigation agency, was responsible for conducting the investigation. The investigation team also included members from Civil Aeronautical Administration (CAA) and EVA Airways. The Final Report was reviewed and approved by ASC’s 75th Council Meeting on January 25, 2019.

Findings related to probable causes:

According to the recorded flight data, during the cruise altitude were at 31,000 feet, the maximum of vertical acceleration was between 1.68g to -0.13g, the maxima of Eddy Diffusion cube root was over than 0.7, which indicated the aircraft was encountering severe turbulence. Since the cabin crew received the turbulence waring during the period of dinning service, they were unable to return and lock up the trollies back in the galley, then be seated. It resulted in 3 passengers and 8 cabin crew members received injuries during the turbulence, 2 were subjected serious injuries among them.

Findings related to risk：

1. There is no procedure for responding predictable turbulence during dining service in relevant the EVA Airways cabin crew manual, only be seated as soon as possible is requested. It takes time to be seated after returning the trollies back to the galley and locking it up, the current procedure is unable to lowers the risk of cabin crew subjected injury in practical.
2. There is no current procedure for turbulence encounters in cruise in EVA Airways to report the moderated or severe turbulence events to the flight dispatching department, this indicates it is not in compliance with the third element of the Advisory Circular which advises to establish an efficient pilot report and communication system for clear air turbulence (CAT) avoidance (not ATC communications), the systems of CAT avoidance were insufficient.

Safety Recommendations

To EVA Airways:

Improve the procedures of cabin crew manual and the cabin crew training, emphasize upon the reactions of turbulence encountering during service, and educate the risks of the turbulence danger.
Comply with the relevant aviation advisories to establish an efficient pilot report and communication system for CAT avoidance in flight.

To Civil Aeronautics Administration, Ministry of Transportation and Communications:

1. Supervise EVA Airways and other national operators to improve the procedures of cabin crew manual and training, emphasize upon the reactions of turbulence encountering during service, and educate the risks of the turbulence danger.
2. Supervise EVA Airways and other national operators to implement the relevant aviation advisories for CAT avoidance in flight.

Full Final Report is in Chinese only and available for download at http://www.asc.gov.tw

Sherry Liu, Engineer
Tel: 89127388-330
Email:sherry@asc.gov.tw