What happened
On the night of December 8, 2012, an All Nippon Airways Boeing 737-800, registered JA57AN, was operating a scheduled flight from Tokyo International Airport to Shonai Airport. The flight, designated as Flight 899, carried 161 passengers and 6 crew members.
During the approach to Runway 09, the aircraft encountered changing weather conditions. Earlier in the flight, the crew had been notified of light snow and ongoing runway condition assessments. After a missed approach was executed to allow for updated snow/ice measurements, the aircraft returned for a second approach. At the time of landing, the wind was reported as 320 degrees at 13 knots, and recent weather observations indicated a light shower of snow and snow pellets.
The aircraft touched down at approximately 22:26 JST within the touchdown zone. However, the aircraft failed to decelerate sufficiently on the runway. The landing roll continued past the end of the pavement, and the aircraft overran the runway, eventually coming to a stop in a nearby grass area. There were no injuries to the 167 people on board, and the aircraft sustained no damage during the incident.
The investigation
The Japan Transport Safety Board (JTSB) conducted an investigation to determine the factors leading to the overrun. Investigators analyzed data from the Digital Flight Data Recorder (DFDR) and the Cockpit Voice Recorder (CVR), and performed detailed inspections of the aircraft's braking systems, including the Antiskid/Autobrake Control Unit (AACU), the wheel assemblies, and the brake assemblies.
The investigation also examined meteorological records, including runway snow/ice condition assessments, and reviewed the airline's operational procedures regarding landing on slippery surfaces. The investigation focused on the relationship between the reported runway conditions and the actual braking performance of the aircraft during the landing roll.