In light of NTSB warning, SEPTA to closely watch Automatic Train Control system

SEPTA has released a set of new policies on the Market-Frankford El to prevent the same type of signaling error that may have contributed to the Washington Metro crash over the summer.

In a series of urgent safety recommendations, the National Transportation Safety Board said that the Automatic Train Control system on the Metro, which is used to prevent collisions, may have had a design flaw that would have prevented the system from working properly.

In that June 22 crash, the NTSB said that “spurious” signals from a train control room gave a false signal to the system, causing it to think the track is clear when it was occupied by a train.

Nine people were killed and 80 were injured in the resulting collision.

Alstom Signaling, which built the Washington ATC system, also built the system currently used on the El in Philadelphia, as well as systems for transit agencies in Boston, Atlanta, San Francisco and Baltimore.

The NTSB told Alstom to work with those transit agencies to test their systems and make sure no malfunctions like this could occur.

In a statement, SEPTA said that it tested the El’s ATC system after the Metro crash and found “no reasons for concern.”

SEPTA tests its track circuits every two years and is in the midst of a current testing cycle, which is “being supplemented to include a specific focus on identifying any possible ‘unintended signal paths’” that were identified in the Metro.

The authority said it has also “initiated new procedures” to more quickly identify a similar signal problem and that when such a condition is discovered, the trains involved will immediately stop. SEPTA has also begun a series of random audits to ensure compliance with the new procedures.

SEPTA “believes the Automatic Train Control system presently employed in our Blue Line train operations are safe,” the statement said.

Posted by Anthony Campisi. Contact him at

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