A summary of past safety troubles and measures
Fatal or serious injury of an person as a result of the operation of an aircraft, or an aircraft crash, collision or fire, as classified by the Japanese Ministry of Land, Infrastructure, Transport and Tourism (MLIT).
On December 9, 2008, JAL 2375 (from Osaka International Airport to Nagasaki Airport) encountered sudden rocking at approximately 25,000 ft altitude during ascent, causing injuries to 2 cabin attendants preparing cabin service in the rear galley. After arrival at Nagasaki Airport, one cabin attendant was diagnosed at the hospital with the fracture of right-foot joint medial and posterior malleolus, and injury of right-foot joint exterior ligament, and the other, fracture of the 1st lumbar vertebra and a sprained neck. As a result, MLIT classified this case as an Aircraft Accident on the same day.
Investigations were conducted by Japan Transport Safety Board, and the results were announced on February 26, 2010. According to their report, during ascent after take-off from Osaka International Airport, the aircraft passed a frontal zone under a jet stream while the seatbelt sign was turned off , rocking the aircraft violently due to turbulence caused by strong changes in winds. This is the assumed cause of serious injuries of two cabin attendants working in the rear galley.
The following measures were implemented to prevent injury caused by turbulence.
Weather information for flight crew to check prior to departure were put up in chronological sequence, making it easier to check changes in turbulence information.
The range of aircraft to notify turbulence information was expanded to increase vigilance of turbulence whose location and force is difficult to predict.
We will continuously improve training about meteorological conditions for flight crew and operation controllers.
On January 27, 2009, JAL 950 (from Seoul to Narita) started meal and beverage service by service cart during cruising at the altitude of 7,000 feet. After that, the service cart moved and stopped at a tilt hitting to the seat. The tea pot on the cart turned over by the shock and one passenger got burned right upper arm by spilled-over tea. As a result, Korean Authorities classified this case as an Aircraft Accident on 30, January.
Japan Transportation Safety Board is delegated by Korean Authorities to investigate the cause of this case. JAL has implemented countermeasures and is providing full cooperation with the investigations.
An incident involving circumstances indicating that there was a high probability of an accident, such as overrunning, emergency evacuation, fire or smoke inside the cabin and abnormal depressurization, encountering abnormal weather conditions, etc, as classified by the Japanese Ministry of Land, Infrastructure, Transport and Tourism (MLIT).
On August 12, 2008, Japan Air Commuter flight 2409 (from Itami to Kagoshima)aborted take-off as the Left Engine emitted a strange sound and lost power during take-off run from Itami Airport. After coming to a stop, the indicator reading of both Engines were normal, but Left Engine power was reduced, and the aircraft returned to the Spot. None of the passengers and crew were injured.
As a result of an inspection, there were no damages to the aircraft, but some of the turbine blades in the Engine were damaged. As the damage corresponded to "large-scale damage of the Engine interior" under the Civil Aeronautics Law Enforcement Regulations, the case was classified as a Serious Incident by MLIT on August 13.
Investigations were conducted by Japan Transport Safety Board, and the results were announced on February 26, 2010. According to their report, it is assumed that the outer circumference of the high pressure turbines deteriorated due to heat and the melted particles stuck to the rear low pressure turbines. The turbines could not be cooled down, were damaged, fell off, and entered the rear high speed rotating area, triggering large-scale damage to the Engine interior and causing rapid loss of Engine power.
The following preventive measures were implemented.
We will continuously improve our activities to enhance aircraft quality.
On March 25, 2009, Japan Air Commuter flight 3760(from Tanegashima to Kagoshima) stopped its Left Engine during climb after take-off from Tanegashima Airport, as instruments indicated a drop in lubricant pressure of the Left Engine. The aircraft requested priority in air traffic control and landed at Kagoshima Airport.
As a result of an inspection after landing, damage was confirmed in the No. 1 Engine Gear connecting area, turbine blades, etc. As the damage corresponded to "large-scale damage of the Engine interior" under the Civil Aeronautics Law Enforcement Regulations, the case was classified as a Serious Incident by MLIT on the same day. None of the passengers and crews were injured.
Investigations were conducted by Japan Transport Safety Board (JTSB), and the results were announced on August 27, 2010. According to their report, the assumed caused is damage to parts in the Engine. In concrete terms, the rotating shaft of the Left Engine was broken during climb after take-off, causing damage to parts in the surrounding area. Fragments of the damaged parts scattered in all directions, damaging the Engine's turbine blades and causing Engine trouble.
As for the cause of the broken rotating shaft, it is assumed that impurities were mixed in the production stage, and it lost its original durability.
As a provisional measure for the broken rotating shaft, the Engine manufacturer instructed the airline to immediately inspect all rotating shafts. Japan Air Commuter inspected and confirmed that there was no trouble with rotating shafts of other aircraft.
As a permanent measure, the Engine manufacturer instructed the airline to replace rotating shafts containing possible impurities with a new one, and Japan Air Commuter followed the instructions.
Furthermore, JTSB issued a safety recommendation to the Civil Aviation Bureau of Canada, the country of aircraft and Engine design and production, that the Engine manufacturer should enforce necessary measures to improve production and quality management of its rotating shaft.