What happened
On July 12, 2023, a Boeing 767-300, registration JA614J, operated by Japan Airlines, was performing a scheduled flight from Tokyo International Airport to Hakodate Airport. The flight, carrying 249 passengers and nine crew members, encountered deteriorating weather conditions upon arrival at Hakodate.
During the initial approach, the pilot in command was unable to establish visual references at the decision altitude, necessitating a go-around. While the crew attempted a second approach, the weather continued to degrade. The crew decided to divert to New Chitose Airport; however, during the process of updating the flight management system for the new destination, they realized that the remaining fuel would fall below the required final reserve levels if they landed on the anticipated runway at the alternate airport.
As a result, the aircraft declared an emergency due to a shortage of fuel requiring urgent measures. The aircraft subsequently landed safely at New Chitose Airport.
The investigation
The Japan Transport Safety Board (JTSB) examined flight data recorder (DFDR) records, cockpit voice recorder (CVR) data, air traffic control communications, and pilot statements. The investigation focused on the crew's fuel management decisions and the discrepancy between the planned alternate fuel and the actual requirements for the diversion. The investigation also noted that the CVR records for the period of the incident had been overwritten before the event was officially classified as a serious incident.