The suspension of all bullet train service Jan. 17 on JR East’s five shinkansen lines ― Tohoku, Akita, Yamagata, Joetsu and Nagano shinkansen lines ― reminds railways and any organization, for that matter, of the importance of sharing important information among personnel concerned and designing a computer system that can flexibly cope with changing situations.
At 8:23 a.m. on that day, a screen of the Computerized Safety Maintenance and Operation Systems of Shinkansen (COSMOS) at JR East’s shinkansen traffic control center in Tokyo blacked out. Traffic controllers halted all of JR East’s shinkansen services until 9:38 a.m., fearing that the system, which controls JR East’s shinkansen network, had broken down.
JR East later explained that the trouble occurred because train schedule changes necessitated after railway switches had frozen that morning in Shin-Shirakawa and Fukushima, Fukushima Prefecture, overburdened COSMOS’ capacity.
Following the railway switch problems, the seven traffic controllers at the center started feeding instructions into COSMOS around 8 a.m. to make 24 shinkansen trains stop at the nearest stations, not between stations. Since the feeds resulted in more than 600 schedule changes on the system display ― past the limit ― the display began appearing and disappearing.
JR admitted that the seven traffic controllers had not been told that there was a limit to the number of changes that COSMOS could handle, although designers of the system knew of the limit. Therefore, this was a typical case of necessary information not being shared among personnel.
When COSMOS began operating in 1995, it handled 230 shinkansen train runs a day. The number has increased to 320 now. It is clear that JR East needs to strengthen the system. Such improvement is important as Japan is trying to sell the shinkansen system, including the train traffic control system, overseas. Each railway firm also should closely examine each glitch in its traffic control system to prevent major confusion from occurring in the future.
(The Japan Times, Jan. 31)