How Do You Say, "Sorry" In Japanese?

The Japanese government blames computer giant NEC for the shutdown of the country's central air traffic control system earlier this month. But the government also says its own technicians overlooked the problem for months.

The failure, which shut down both the main computer and its backup at 7 a.m. on March 1, forced the delay of hundreds of thousands of passengers and prompted the cancellation of more than 200 flights over a period of 48 hours.

Investigators eventually identified the problem as a defect in a program installed by NEC on the central air traffic control system. The program collects flight data from airports nationwide and feeds it to air traffic controllers, according to a statement by the transport ministry.

How Do You Say "I'm Really Sorry"?

Aviation bureau technicians realized the program running on the flight data processing system was flawed when it was installed in September, but dismissed the error as too small to cause serious problems, the statement said.

In January, NEC technicians discovered the same defect but decided not to report it as the system had been running smoothly for four months and left it unfixed.

"The problem was not believed to be of great consequence," said transport ministry spokesman Motohiro Kaneko.

When technicians made changes to a related program on the morning of March 1, it paralyzed the entire system, disabling automatic data transmission of all departures to and from air traffic controllers.

The ministry acknowledged that it failed to test sufficiently for incompatibilities before the other program was updated that morning.

NEC: Our Bad

NEC said in a statement, "We have confirmed that a mistake in a program made by our company was the cause of the... obstruction of March 1." There's no indication yet of what penalties NEC may have to pay, if any.

Aviation and NEC officials said it was highly unlikely other traffic control systems around the world were vulnerable to the same problem.

"Logically speaking, unless they run the same program on the same set up, it would be unlikely," said Kaneko.

Technicians reversed the changes that had prompted the shutdown and had the main computer system up and running within an hour. The planned updates were still being completed, Kaneko said.

All domestic and international flights were grounded for at least half an hour after the failure occurred, but delays continued for two days because of the backlog of earlier flights.

In total, over 200 flights were canceled, while about 1,300 were delayed.

FMI: www.mlit.go.jp/english