Wednesday, June 24, 2009

The Metro Crash

In the immediate aftermath of Monday's crash along the DC Metro's Red Line, many people assumed that it was the train's operator that had screwed up. This jumping to conclusions was probably understandable to a point. After all, last year a commuter rail engineer in California caused a major accident when he ran a signal while texting on his cellphone.

It is now beginning to look like Jeanice McMillan, the train operator in the DC crash, was as much a victim as the eight passengers who died. According to a Metro spokesperson, the train that caused the accident was operating in fully automatic mode. That means that it was Metro's own computers--not the train operator--that was in charge. The computer controls the train's speed, it's braking, and the distance between trains. There is also evidence that the operator hit the emergency brake in the moments before the crash. This would indicate that she was fully aware of what was about to happen.

Thus the question becomes: What went wrong with Metro's computers? According to the various safeguards built into the system, an accident such as the one two days ago was simply impossible. The computers wouldn't allow two trains to get that close to one another.

It was also revealed that a similar incident happened a few years ago along the Orange Line. In that 2005 episode under the Potomac, a train operator noticed that he was getting too close to the train in front of him even though the signal system was telling him the tracks were clear. He hit the emergency brakes and managed to prevent disaster. A third train behind his also managed to stop in time. Metro officials launched an investigation but at this point it remains unclear whether they ever figured out what went wrong.

In another revelation, it turns out that the two lead cars of the train that caused Monday's accident were overdue for an inspection of their braking systems. What the hell is that about? And how many more trains does Metro have running that are also past due on safety checks?

And if that's not enough, it turns out that the transit agency disregarded safety recommendations from the National Transportation Safety Board (NTSB) following previous accidents. One was to install data recorders on the trains to aid in future investigations. The second was to strengthen older rail cars to prevent the very "telescoping" effect that caused Monday's loss of life. In both cases, Metro cited a lack of funds as the reason it couldn't follow through.

For what it's worth, there was a somewhat fortuitous angle to the crash. The trains involved were both heading southbound, from suburban Maryland into DC. Since it was the evening rush hour, that means they were substantially less crowded than trains heading northbound out of the city. Had it been the other way around, with the rail cars packed with standing room only crowds, the loss of life would have been far higher.

0 thoughtful ramblings: