JR East Official Issues Apology over Tohoku Shinkansen Decoupling; Cause Likely Different to September Accident

The Yomiuri Shimbun

15:05 JST, March 7, 2025

A senior official of East Japan Railway Co. (JR East) issued an apology regarding an incident involving cars on a Tohoku Shinkansen train decoupling on Wednesday, which temporarily suspended operations on the line, at a press conference on Thursday.

The company has canceled train operations in which different car types are coupled on Friday and is set to extend the cancellation to Saturday.

In the accident, a coupler connecting Komachi cars, owned by JR East, with Hayabusa cars, owned by Hokkaido Railway Co. (JR Hokkaido), while it was running. A similar problem also occurred last September.

“A serious situation developed that should never have occurred during train operations, and it has greatly damaged people’s trust in the Shinkansen,” said Hirohiko Ikeda, director general of the company’s Shinkansen General Management Department.

When JR East inspected the Komachi car, there was no damage to the coupler. However, they found a defect with the electrical system and evidence that a malfunction leading to the decoupling took place.

In last September’s accident, a piece of metal was found behind the switch that forcibly separates the coupler on one car, and it was determined that the switch most likely malfunctioned as a result. All 96 Shinkansen trains that operate in a couple, including the two involved in Wednesday’s accident, had been inspected.

Ikeda expressed his view that the cause of the two accidents were different and said, “We believe that it is highly possible that the problem [regarding Wednesday’s accident] is on the Komachi side.”

About three hours after the emergency stop, the separated Komachi and Hayabusa trains were moved separately to Omiya Station in Saitama. Passengers transferred to other Shinkansen and regular trains to continue their journeys. The accident caused a total of 277 trains, including others operating on the Tohoku Shinkansen line, to be suspended or delayed, affecting about 153,000 passengers.

“It is extraordinary that there have been a pair of accidents where Shinkansen trains have decoupled,” said Hitoshi Tsunashima, project professor at Nihon University’s department of mechanical engineering. “A thorough investigation into the cause and measures to prevent such accidents will be necessary to restore public confidence.”

Transport minister Hiromasa Nakano, in a press conference after the Cabinet meeting on Friday morning, said: “We are taking this matter very seriously. We will provide appropriate guidance to the train operators to ensure safe and stable rail transportation after receiving accident reports from JR East and JR Hokkaido.”

The Japan Transport Safety Board on Friday afternoon dispatched three railway accident investigators to JR East’s Shinkansen general rolling stock center in Rifu, Miyagi Prefecture, where the cars that disconnected were housed, to conduct interviews and check the cars to determine the cause of the accident.

The ministry and the safety board designated the accident a serious incident under the Railway Business and other laws, due to its similarity with the accident in September.