Shinkansen outage dampens export ambitions
2011/01/20
Naoto Miyashita, executive officer at JR East, apologizes at a news conference Tuesday. (Hiroyuki Yamamoto)
The outage of Shinkansen services operated by East Japan Railway Co. on Monday morning could have been avoided if the centralized computer train management system had been upgraded, JR East officials said.
The situation presents a mark of embarrassment as Japan tries to export its rapid train technologies overseas and will force Tokyo to review its infrastructure export strategy.
JR East had put off upgrading the COSMOS system that controls all five Shinkansen lines since it was introduced more than 15 years ago, despite a 40-percent increase in trains operated on arteries serving the northern reaches of Honshu.
Officials are also questioning the design of the system itself, which was unable to handle the increased traffic.
Japan has been fervently trying to export Shinkansen technology to the United States, Brazil and Vietnam, which plan to build rapid train lines.
The COSMOS system oversees the operations of the Tohoku, Joetsu, Nagano, Yamagata, and Akita Shinkansen lines.
According to officials, the confusion started when JR East tried to rearrange schedules for 24 bullet trains after a track-switch point malfunctioned on the Tohoku Shinkansen Line in Fukushima Prefecture due to heavy snow.
Under normal conditions, when a delay occurs, an operator of the COSMOS system amends the schedule, which is then transmitted to all scheduled stops accordingly.
However, when the amount of data to be amended exceeds a maximum 600 items--set as COSMOS' processing limit--the computer ceases to indicate the arrival times on terminal monitors. This caused the arrival times at each station along the Tohoku Shinkansen Line to disappear from the displays of all 22 train scheduling terminals at the operations center in Tokyo.
As data was being updated by the minute, the electronic updates appeared and disappeared from the monitors while officials struggled to fix the schedule.
While system managers and operators were aware of the system's characteristics and the processing volume limit, those in charge of giving operational orders were not informed, leading them to assume a system glitch.
As a result, operations officials took procedures to stop all trains.
JR East Executive Director Naoto Miyashita apologized at a news conference Tuesday, saying what initially was thought to have been a system glitch "was human error."
Miyashita went on to explain that the supervisor of operations had not been informed about the nature of the system out of fears that "if we were to inform those in the operation room, they would not be able to concentrate on managing the train schedules."
Miyashita said he initially believed that the system had been designed with some leeway to handle excess traffic, but acknowledged that the system's capacity had never been upgraded since being put in use in 1995.
Over the last 16 years, the total number of trains running per day rose from about 230 to about 320.
In May 2008, a train schedule simulation function inside the COSMOS system was extended from a maximum four hours ahead of time, to cover services all the way until the last trains of the day. However, again the data processing capacity was not revised, leading to suggestions that the system design itself may have been insufficient.
Officials said that JR East will likely look into reviewing its rescheduling procedures to reduce the burden on the system, and raising the limit of data that can be handled.
Another incident in which train services were stopped because of lack of awareness toward the characteristics of the COSMOS system occurred in 2008, when trains were halted for up to three hours, affecting 138,000 passengers on the same five lines.
Meanwhile, a separate case of human error caused trains to be suspended for up to four hours on Jan. 15 on the Tohoku, Yamagata and Akita Shinkansen lines after shoddy inspections failed to catch a worn power main near Oyama Station in Tochigi Prefecture that malfunctioned.
One of the key sales pitches for the Shinkansen in competing with rival exports offered by China and South Korea has been punctuality, with an average delay time per train of 30 seconds, including delays due to natural disasters.
The latest embarrassments prompted transport minister Akihiro Ohata to declare Tuesday that the government would take steps to assure that no doubts will be raised over Japan's drive to export Shinkansen technology.
Ohata summoned senior JR East officials to sound them out and receive an explanation on the cause of the outage, which inconvenienced more than 81,000 passengers.
新幹線ストップ、ソフトに不具合か 到着時刻表示されず
2011年1月18日6時13分
運行ダイヤを示す線が異常になった「ＣＯＳＭＯＳ（コスモス）」のモニター＝ＪＲ東日本提供
ＪＲ東日本の五つの新幹線すべてが一時止まった１７日のトラブルは、運行管理システムのソフトの不具合が原因だった可能性が高いことが、同社への取材で分かった。１５本が運休し、１２４本が最大２時間１３分遅れ、影響した乗客は約８万１２００人に膨らんだ。
ＪＲ東では１５日にも小山駅（栃木県小山市）で架線が切れて信号機も故障。東北、山形、秋田の各新幹線が最大約４時間止まるトラブルがあった。国土交通省関東運輸局は１７日午後、ＪＲ東に二つのトラブルの原因調査と再発防止を求める警告文を出した。
ＪＲ東によると、トラブルが起きたのは「ＣＯＳＭＯＳ（コスモス）」と呼ばれるシステム。都内の新幹線運行本部室内にあるダイヤ管理用モニター２２台の すべてで、到着予定時刻を示す青い線が正常に表示されなくなった。各駅に運行データがきちんと届いているか確認するため、全列車を止めたという。
ＪＲ東は、システムのソフトに不具合があった可能性が高いとみている。列車を止めてテストデータを送ったところ、駅の端末で適正に受信。モニター表示も約３０分後には正常に戻った。
このシステムは２００８年１２月にも人為的ミスで不具合を起こし、始発から約３時間にわたってすべての新幹線が止まるなど、過去にも何度かトラブルが起 きている。ソフト更新など改修直後が大半という。しかし、担当者は「昨年１２月のダイヤ改定以降は改修しておらず、今回は心当たりがない」と話しており、 ソフトを開発したメーカーとともに調べている。
ＪＲ東は１９９５年、新幹線網が拡大したためにコスモスを使い始めた。運行管理や情報監視など七つのサブシステムに分かれ、新幹線の運行にかかわるすべての業務を一元管理している。
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