All people escaped from the disabled JAL aircraft
Video footage from social media and other sources shows passengers sliding down one after another from the three exits. Overseas media has described the fact that everyone on the commercial flight survived as a "miracle." But on the Coast Guard side, five people, not including the captain, were killed.
Soon after the JAL plane stopped, the fire spread to the fuselage, which was scorched beyond recognition.
Communication logs with the control tower
It was also confirmed that the Coast Guard plane had stopped on the runway for about 40 seconds before the collision. The air traffic controllers were not aware of the impending danger. Nikkei looked at the communication records, which have become a focal point in the incident.
Communication records released by Japan's Ministry of Land, Infrastructure, Transport and Tourism
TIME(JST)
STATION
CONTENTS
Situation
17:43:02
JAL516
Tokyo TOWER JAL516 spot18.
Situation The JAL aircraft was approximately 1,100 meters above Chiba prefecture. The control tower had instructed it to continue its approach.
Tokyo TOWER
JAL516 Tokyo TOWER good evening RUNWAY 34R continue approach wind 320/7, we have departure.
17:43:12
JAL516
JAL516 continue approach 34R.
Audio communication records
17:44:56
Tokyo TOWER
JAL516 RUNWAY 34R cleared to land wind 310/8.
17:45:01
JAL516
Cleared to land RUNWAY 34R JAL516.
Audio communication records
17:45:11
JA722A
TOWER JA722A C.
Situation The control tower communicates with the Coast Guard aircraft. No permission to enter the runway is given.
Tokyo TOWER
JA722A Tokyo TOWER good evening, No.1,taxi to holding point C5.
Audio communication records
17:45:19
Tokyo TOWER
Taxi to holding point C5 JA722A No.1, Thank you.
SituationThe Coast Guard aircraft said to the control tower, "Number one. Thank you." It is thought that it headed to the runway shortly after that.
We extracted voice communication from LiveATC.net based on recently released records, then adjusted the audio quality.
The Coast Guard captain said after the accident that they had "obtained permission." The understandings of the two sides differ. It is possible that there was a mistake in communicating the instructions, or other miscommunications.
Unanswered questions
Why did the Coast Guard aircraft enter the runway?
The Coast Guard aircraft was told to "taxi to holding point C5," and it repeated these instructions accurately. But the aircraft did not stop at the position as instructed, and incorrectly entered the runway. The standardized statement used by the control tower to authorize entry is "Line up and wait." The wording is clearly different. It is hard to imagine a misunderstanding of the instructions, and it remains unclear why the Coast Guard aircraft acted as it did.
Why could the JAL aircraft not avoid the collision?
The Coast Guard plane was stationary on the runway for about 40 seconds. The JAL captain said that they "could not see it." Why did none of the three pilots on board the JAL flight notice anything unusual? One possibility is the head-up display used to assist in landing. The pilot looks at the runway through this screen. It is possible that the information display covered the Coast Guard aircraft. It was dark after sunset, and the fact that the Coast Guard aircraft was smaller than ordinary civilian aircraft may have also been a factor.
Why could the control tower not prevent the accident?
The air traffic controllers were also unable to notice the erroneous approach of the Coast Guard aircraft. Air traffic control has a function that alerts it if another aircraft approaches the runway that a landing aircraft is approaching. It is believed that the person in charge did not notice the warning of flashing lights on the screen. Another system, which prevents aircraft from moving if they fail to hear or misinterpret instructions, was also under development. Even if it had been in operation, it did not meet the operational conditions at the time of the accident, when visibility was excellent.
The Japan Transport Safety Board has already recovered the voice recorders of both the Coast Guard and JAL aircrafts and has begun interviewing air traffic controllers. The circumstances surrounding the accident have not yet been made fully clear.
Expert views
Former chief air traffic controller
Hidetaka Tanaka
Any of the three sides could have prevented the accident
Air traffic controllers and pilots use a standardized communication format to avoid misunderstandings. According to the communication records released by the Ministry of Land, Infrastructure, Transport and Tourism, the Coast Guard aircraft accurately repeated instructions from the air traffic controller, and there were no unnatural points or miscommunications.
There are reports that the Coast Guard aircraft was on a disaster relief mission and was significantly delayed. There were also several commercial aircraft waiting for permission to enter the runway. The control tower informed the Coast Guard aircraft that it was "Number one [to take off", to which the Coast Guard responded, "Thank you." The possibility cannot be ruled out that, perhaps out of impatience, the Coast Guard aircraft thought it had been given permission to enter the runway and take off.
Aircraft accidents are often the result of a combination of multiple errors. The accident could have been prevented if the two pilots of the Coast Guard plane had thoroughly checked for approaching landing craft when they entered the runway. The Coast Guard plane was stationary on the runway for 40 seconds. Even though it was difficult for the air traffic controllers to see at night, they would have had the opportunity to note the erroneous approach if they had kept a close eye on the aircraft.
Couldn't any of the three pilots on the JAL plane also have noticed it? Is the head-up display in the cockpit, which is increasingly being installed in newer aircraft, creating a situation where it is difficult to see?
All three parties -- the Coast Guard aircraft, the air traffic controller and the JAL aircraft -- could have prevented the accident. It is essential to thoroughly investigate the accident and ensure there are no repeats of it in the future.
Research Center for Advanced Science and Technology, The University of Tokyo
Eri Itoh
New tech needed to assist air traffic controllers
The current infrastructure foundation for air traffic management was established during the 1950s and 1960s. Then, with the development of communication, navigation, and surveillance technologies and the availability of digital data, reforms began around the world in the 2000s. The research and development of a system in which air traffic controllers and pilots communicate not by voice but by data, and a system that shares flight information on all aircraft at an airport to safely and automatically control the interval between takeoffs and landings, is also moving forward.
The obstacle is the cost. In particular, without economic advantages and support, new technologies will not be introduced to aircraft. International collaboration among industry, academia and government must be promoted. Manufacturers, researchers, pilots, air traffic controllers, and domestic and international government agencies need to come together and align themselves. Japan should take a more active role in developing international standards.
When accidents such as this occur, it is important to thoroughly investigate the causes, as well as enact laws to ensure that responsibility for human error is not placed on any particular individual or organization. We must facilitate clarification of the circumstances of this accident and introduce new technology to assist air traffic controllers and pilots in preventing a recurrence.
Haneda Airport in data
Growing use, constant traffic
Annual departure and arrival slots at Haneda Airport
Haneda has been increasing its aircraft capacity to accommodate the growing number of visitors to Japan. In 2010, the airport began using a fourth runway, and the number of departures and arrivals swelled to 486,000 per year. According to the Airports Council International (ACI), there are as many as 90 takeoffs and landings per hour.
One of the most congested airports in G7 countries
Number of flights scheduled to take off and land on Jan. 1, 2024
According to data from the British aviation analytics company Cirium, Haneda has the most takeoffs and landings among major airports in the G7 countries after Dallas Fort Worth Airport and Atlanta International Airport in the U.S. On Jan. 1, the day before the accident, there were a total of 1,297 flights.
Research and analysis methods
The movement of the JAL plane was reproduced based on data from global flight tracking service Flightradar24. Nikkei analyzed the disaster using photos and videos from social media, videos from live cameras, aerial photographs taken on the day following the collision, and others. We prepared 3D models of the planes with matching dimensions and digitally reproduced the event. We were advised by Hidehiro Hata, an assistant professor at Kumamoto University in Japan, who is an explosives expert.