Before Accident, Track Walkers Found No Flaws on Red Line Rail

Metro personnel conducted track inspections a week before and again hours before Friday's double derailment on Metro's Red Line and found no visible problems with the rail, officials said yesterday.

A broken piece of rail in the tunnel between the Bethesda and Friendship Heights Metro stations caused two trains to derail, one after the other, during the afternoon rush. No injuries were reported, but delays lasted through the weekend on Metro's busiest line. Trains heading in and out of the District took turns sharing the same stretch of useable track between the Friendship Heights and Medical Center stations while crews replaced about 2,000 feet of track.

There have been two other derailments involving rail cars on the main line in 12 months. No injuries were reported in any of the incidents. An Orange Line train derailed outside an Arlington County station in June, and a Yellow Line train derailed at Mount Vernon Square in February. Maintenance vehicles have also derailed.

In the wake of Friday's incident, Metro Deputy General Manager Gerald Francis said officials are conducting a comprehensive review of all operations procedures, including track inspections and training. "We want to step back and look at everything," he said.

A spokesman for the National Transportation Safety Board, which has investigated several Metrorail accidents, said it is monitoring the latest incident.

Metro track walkers inspect stretches of the system's 106 miles of main line track every day. They also perform ultrasonic testing five times a year. An inspection crew found nothing unusual during the day Friday, according to Metro rail chief Dave Kubicek. Ultrasonic testing of the entire Red Line conducted from March 15 to March 19 also found no defects.

But ultrasonic testing does not pick up "very, very small blemishes" on the rail surface, he said. Those blemishes can cause the rail to deteriorate over time, a process known as "shelling," said Kubicek, who was at the Bethesda Station through the weekend overseeing repairs.

Other possible factors include damage from water that "picks up minerals" while leaking from tunnel walls onto the track, he said. Electrical damage is also possible because Metro has increased power usage to run longer trains.

"We wear rail and use electricity faster" than any other transit system in the nation, Kubicek said. The contact between the rail cars and the track "is no wider than a dime," he said. Metro has ramped up the number of rail cars it runs during peak periods, and the pounding is adding to wear-and-tear on the rails.

Metro plans to send samples of the affected portion of rail to labs that do similar work for aircraft damaged in crashes to determine the cause of the break, he said.

Kubicek said rail personnel, starting last week, have begun examining in detail how well the trains are running on the track. To do so, they attach a camera to the underside of a rail car to film the interaction between the wheels and the running rails, as well as the interaction between the special rail car equipment and the electrified third rail that powers the trains.