When one subway train crashed into the rear of another in Washington this week, killing nine, it quickly raised a question in Baltimore: Could it happen here?
Maryland Transit Administration officials aren't taking any chances. Just to be safe, MTA Administrator Paul J. Wiedefeld has ordered an "integrity test" to see how the Baltimore subway's train operation and collision-avoidance systems would perform in a crisis.
MTA officials, who don't think an accident like Washington's could happen in Baltimore, are designing a series of tests to simulate potential problems. The tests will be conducted in the early-morning hours when the Metro has no scheduled service.
"We're going to try to set up something where there's a series of failures," said Henry Kay, MTA deputy administrator. "We need to create some really challenging circumstance that's unlikely but credible."
Baltimore's subway has had one fatal accident since it opened in 1983, according to the MTA. But occasional problems - including the December 2007 failure of an automatic system that governs train speeds - have required the agency to take action.
Kay said the MTA is not running the tests out of a state of alarm, but just to make sure nothing could go wrong. He said the Washington and Baltimore systems are not similar.
Washington's subway is a vast network of five lines that is part of the fabric of the entire capital region. Baltimore's is a single line serving one corridor; many longtime area residents have never ridden it and are only vaguely aware it exists.
The two systems also have far different records when it comes to safety. With the nine fatalities in Monday's crash, Washington's Metro has seen at least 17 passengers and employees die on its tracks since opening in 1976. According to the MTA, the lone Baltimore fatality occurred when an employee was killed in a train yard during the 1980s.
MTA officials are proud of the Baltimore Metro's safety record but recognize that their agency doesn't face as much of a challenge as the Washington Metropolitan Area Transit Administration, operator of the capital's subway system. The Washington system provides an average of about 750,000 rides on an average weekday; Baltimore's averaged 46,587 daily trips during the first three months of this year.
Baltimore's Metro is "a much smaller system, so we're not tested each day in the way WMATA is," Kay said.
The Baltimore Metro did face a test of its backup systems as recently as December 2007, when a train operator noticed that the subway's automatic operating system had set a speed of 40 mph for a train that was about to enter a station, MTA spokeswoman Jawauna Greene said. In that case, she said, the human operator recognized the computer's improper speed setting and stopped the train.
Greene said MTA officials found a problem with a circuit board that prompted the system to send a false speed code. The MTA contacted the manufacturer, United Switch & Signal, which worked with the agency to develop a fix, and then repaired and tested all of the circuit boards in the system.
"It's important to note that we do not have the same system as WMATA," Greene wrote in an e-mail. "To date, we have not had a reoccurrence."
Passengers at the Charles Center Metro Station said the Washington crash had aroused some concern - but not enough to keep them off the subway.
"Maybe something good will come of this," said Paula Jordan of Baltimore. "Maybe now people will be more careful on trains and be more aware."
Baltimorean Carol Johnson noticed that passengers were avoiding cars where a collision would be felt first. "Usually there are a lot of people in the end cars, but today there were more sitting in the middle. I didn't sit on the end."
Like other transit systems, Baltimore's Metro has multiple levels of protections.
The automatic train operating system does most of the driving, while the operator is there to respond to emergencies and to take manual control when directed by the control center. In addition to the operating system, trains are equipped with a safety system called automatic train protection, which is designed to stop the train if it detects another on the same track at too close a distance or if a prescribed speed is exceeded for longer than three seconds.
In the Washington crash, the National Transportation Safety Board is investigating why the automatic operating system allowed one train to plow into the rear of a train stopped on the tracks ahead of it. The NTSB has found evidence the operator applied the emergency brake, but is trying to find out why she was unable to stop in time. She was among the nine fatalities.
Kay said the MTA will conduct a more specific examination of its systems if the NTSB investigation points to specific failures. He noted that the NTSB routinely sends out alerts when it finds problems in one agency that could be common to an entire industry.
