The Washington Post, 1/25/18:
Metro defends track inspections, radio signal system in aftermath of derailment
Rust was found on the steel rail that fractured in a Red Line derailment near Farragut North last week, but the cracked rail that probably caused the crash would have been imperceptible to track walkers and ultrasonic inspection technology, Metro officials said Thursday.
Agency investigators are awaiting the results of metallurgy testing by outside experts, which are expected next month and may give a clearer indication about what caused the eight-foot section of track to crack at the start of the morning rush on Jan. 15.
Metro officials also discovered that the agency’s communications maintenance unit failed to keep up with prescribed inspection schedules of the radio signal system — a potential reason it took Metro’s traffic control center more than 10 minutes to receive an update from the train operator and determine that a derailment had occurred.
SNIP
“You can have all these layers of defenses, but if you have something on the bottom of the rail, that is not detectable with all the technology in the world,” Lavin said.
Metro Board member Robert Lauby, chairman of the panel’s safety committee and chief safety officer at the Federal Railroad Administration, said the derailment may have been a case of bad luck.
“It’s too bad that we had this accident. In my experience at FRA, broken rail accidents are the number one cause of derailments on mainline railroads in this country,” Lauby said. “We have processes in place to try to detect whatever we can, and it’s not always possible to find everything.”
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