Same circuit board used in two bullet train decouplings
East Japan Railway Co. (JR East) has revealed that two recent decouplings of Tohoku Shinkansen mid-journey involved different Komachi trains that used the same electrical circuit board, which may have triggered the malfunctions.
Following the first decoupling in September, JR East determined that a small metal fragment left over from the manufacturing process may have caused a false unlocking signal by entering the coupler's control switch.
In response, company engineers inspected all 96 train units capable of coupled operations and cleared any metal fragments. They also removed parts behind the control switch for modifications to prevent a recurrence.
One of these modified parts--a circuit board from the first train malfunction--was later installed in the train that experienced the second decoupling in March.
The circuit board in question has been removed and is now undergoing a thorough investigation to determine whether it was responsible for both decoupling mishaps.
In the second incident, officials confirmed that the lever designed to unlock the coupler repeatedly failed. However, the exact cause for the malfunction remains unknown.
The recent discovery involving the circuit board has prompted JR East to re-examine whether the first incident was actually triggered by a loose metal fragment.
In addition to its own investigation, the company is cooperating with a probe by the Japan Transport Safety Board, which has classified the incidents as serious. Along with safety concerns, the malfunctions inconvenienced hundreds of thousands of passengers as hundreds of trains were canceled.
Shortly after the suspension of operations that followed the second incident, JR East resumed coupled train operations using temporary preventive measures.
It installed additional metal components designed to physically prevent the coupler from disengaging trains, even in the event of an electrical signal malfunction.
JR East President Yoichi Kise has announced plans to introduce a permanent double-locking mechanism in the safety system to prevent mid-operation decoupling.
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
SoraNews24
2 days ago
- SoraNews24
Mobile battery fire breaks out on Tokyo's main commuter line
Battery began to burn after less than a minute of use, owner says. Tokyo's Yamanote Line, which loops around the center of the city, is Japan's most infamously crowded commuter train line, and a stressful should-to-shoulder stint on it is part of the daily trip to/from the office for many Tokyoites. The atmosphere tends to be more relaxed outside of rush hour, and on weekends in particular, but last Sunday was a startling exception. At around 4:10 in the afternoon on July 20, passengers on a train traveling on the Yamanote's 'inner'/counterclockwise route between Shin Okubo and Shinjuku Stations noticed white smoke rising from the bag of a passenger. The bag's owner, a woman in her 30s, reached inside, where she had her smartphone connected to a mobile battery for charging. She disconnected her phone, but by this time the battery itself was on fire. A passenger hit the emergency stop button while another quick-thinking individual grabbed the train car's onboard fire extinguisher and began spraying the bag. The woman sustained burns to her fingers and a total of four other passengers suffered injuries such as bruises and sprained ankles in the rush to evacuate the train, but all are expected to make quick and complete recoveries. ▼ A report showing images of the charred remains of the bag the battery was inside. In speaking with investigators from the Tokyo Metropolitan Police, the woman said that she'd only had her phone plugged into the battery for 'about 30 seconds' before it began to burn. While there's obviously ever a good time for a fire to break out in an enclosed space, it's fortuitous that the incident happened when it did, at a time when the train was comparatively uncrowded. During weekday morning and evening rush hours, it's the norm for the Yamanote Line to be so crowded that it's impossible to take a step in any direction unless the train is stopped at a station with its doors open and providing the bare minimum of wriggle room. The weekend mid-afternoon time also likely meant a lower ratio of sleepy, work-exhausted, on-their-way-home-from-drinking, or otherwise slow-reacting demographics that sometimes make up a sizeable amount of Yamanote ridership. Had the timing been different, the results of a fire inside a Yamanote train and subsequent hurried evacuation would have been far worse than a half-dozen or so minor injuries. The incident comes less than two weeks after Japanese airlines instituted new rules for passengers regarding mobile batteries onboard airplanes. Currently JR East/East Japan Railway Company, which operates the Yamanote Line, has no formal regulations about the use or transport of mobile batteries on its trains, but Sunday's fire may have the company considering adopting some, especially as the National Institute of Technology and Evaluation says that it has observed increased instances of mobile battery fires coinciding with higher temperatures during the summer months. Source: NHK News Web, Nihon Keizai Shimbun via Hachima Kiko, YouTube/ANNNewsCH Top image: Pakutaso ● Want to hear about SoraNews24's latest articles as soon as they're published? Follow us on Facebook and Twitter!
Asahi Shimbun
02-06-2025
- Asahi Shimbun
Same circuit board used in two bullet train decouplings
The decoupled Hayabusa and Komachi bullet trains in Tokyo's Arakawa Ward on March 6 (Yasumasa Kikuchi) East Japan Railway Co. (JR East) has revealed that two recent decouplings of Tohoku Shinkansen mid-journey involved different Komachi trains that used the same electrical circuit board, which may have triggered the malfunctions. Following the first decoupling in September, JR East determined that a small metal fragment left over from the manufacturing process may have caused a false unlocking signal by entering the coupler's control switch. In response, company engineers inspected all 96 train units capable of coupled operations and cleared any metal fragments. They also removed parts behind the control switch for modifications to prevent a recurrence. One of these modified parts--a circuit board from the first train malfunction--was later installed in the train that experienced the second decoupling in March. The circuit board in question has been removed and is now undergoing a thorough investigation to determine whether it was responsible for both decoupling mishaps. In the second incident, officials confirmed that the lever designed to unlock the coupler repeatedly failed. However, the exact cause for the malfunction remains unknown. The recent discovery involving the circuit board has prompted JR East to re-examine whether the first incident was actually triggered by a loose metal fragment. In addition to its own investigation, the company is cooperating with a probe by the Japan Transport Safety Board, which has classified the incidents as serious. Along with safety concerns, the malfunctions inconvenienced hundreds of thousands of passengers as hundreds of trains were canceled. Shortly after the suspension of operations that followed the second incident, JR East resumed coupled train operations using temporary preventive measures. It installed additional metal components designed to physically prevent the coupler from disengaging trains, even in the event of an electrical signal malfunction. JR East President Yoichi Kise has announced plans to introduce a permanent double-locking mechanism in the safety system to prevent mid-operation decoupling.
The Mainichi
21-04-2025
- The Mainichi
Dating app woes and a bullet train altercation: Our 5 most-read stories from last week
We've listed our five most read stories on The Mainichi news site, from top to bottom, that were published between April 12 and 20. The first story was viewed by 27.8% of our regular readers. (The Mainichi) Tokyo woman regrets meeting 'single' man via dating app after she's left with child TOKYO -- A woman in the Japanese capital cannot help but feel her dignity was trampled upon after she met a man through a dating app, got impregnated by him and gave birth, only to end up finding out that the man had a family despite having said he was single upon their first meeting in person. Full story. Altercation on bullet train in northeast Japan causes window damage, delay TOKYO -- Trouble between a passenger and a conductor aboard a bullet train on the Tohoku Shinkansen Line in northeastern Japan resulted in damage to a window, causing delays to the service, East Japan Railway Co. (JR East) announced on April 13. Full story. Ex-bus driver in Kyoto loses $84,000 retirement pay for embezzling $7 TOKYO -- Following a Supreme Court ruling, a former Kyoto City Bus driver has lost retirement pay of some 12 million yen (about $84,000) for pocketing 1,000 yen ($7) from a passenger fare. Full story. Tokyo school operator sues 8 people for $5.1 mil. in damages, releases defendants' names TOKYO -- Musashino Higashi Gakuen, an educational corporation operating schools in Musashino, Tokyo, announced April 15 it had filed a lawsuit seeking some 725.72 million yen (about $5.1 million) in total damages from eight people, including a graduate who previously filed a criminal complaint against its chairperson. Full story. How do doctors detect 'hypothyroidism' that claimed life of Japanese singer Ayumi Ishida? TOKYO -- Singer and actor Ayumi Ishida, best known for hits such as "Blue Light Yokohama," died at a hospital in Tokyo in March at age 76 due to hypothyroidism, a type of thyroid hormone deficiency. Her death prompted specialists to highlight the importance of early detection of this disease, which is relatively common among women, yet seldom fatal. Full story.
