2024 Haneda Airport runway collision

Investigation

The Japan Transport Safety Board is the lead agency for the investigation. The French Bureau of Enquiry and Analysis for Civil Aviation Safety (BEA) announced on Twitter that they will be cooperating with Airbus during the investigation. It also added that it would send a team to Japan to investigate the accident, as part of their protocol for accidents involving an Airbus aircraft. UK investigators from the A350 engine manufacturer Rolls-Royce also planned to join them. The Transportation Safety Board of Canada, along with technical advisers from the Dash 8's manufacturer De Havilland Canada and engine manufacturer Pratt & Whitney Canada, announced they would also be taking part in the investigation. The United States' National Transportation Safety Board (NTSB) will also provide assistance in the investigation.

On 3 January, the MLIT released the transcript of air traffic control communication, covering the last 4 minutes and 27 seconds before the crash. It showed that prior to the accident, air traffic controllers cleared the JAL aircraft to land on runway 34R, while the Coast Guard aircraft was instructed to hold short of the runway at a holding point on taxiway C5. NHK, however, citing a source within the Coast Guard, reported that the pilot of the Coast Guard plane claimed to have received clearance to take off. Air traffic controllers later told MLIT officials that they had not noticed the Coast Guard plane moving onto the runway, adding that they were preoccupied with assisting other aircraft. An MLIT official said that the pilot of the Coast Guard aircraft may not have heard the air traffic control tower authorizing the JAL aircraft to land as his radio could have been set to ground control. Another MLIT official also said that the Coast Guard was not informed of measures introduced by a government task force to prevent airport runway incursions following similar accidents in 2007. Japanese police were reportedly investigating possible professional negligence, including fatigue and staffing levels, that may have caused the accident.

By 6 January, the flight data and cockpit voice recorders of both aircraft had been recovered, with the Japan Transport Safety Board saying on 23 January that they had not sustained major damage.

On 24 June, the MLIT released the first interim report. The investigation pointed out issues such as the lack of personnel gathered at the airport and the delay with the guidance of emergency vehicles. Moreover, it was revealed that over 100 emergency vehicles were waiting to enter the airport and several ambulances carrying injured passengers were unable to leave for about 30 minutes. For future measures, the ministry is scheduled to revise its emergency guidance by August and also requested the number of airport staff that are available to respond to such emergencies on holidays and at night be increased.

A progress report was released by the Japan Transport Safety Board on 25 December 2024. The report indicated that the captain of the Coast Guard aircraft mistook air traffic control's instruction when their aircraft was told that they were "number one," and entered runway 34R believing that takeoff clearance was given. The report added that neither the controller in charge nor the JAL pilots noticed that the Coast Guard aircraft had entered the runway, and that the three circumstances combined resulted in the accident. It also provided details on the evacuation of the JAL plane, and the actions of its pilots and cabin crew.