Metro began testing two trains with 7000 series railcars Monday.
The transit agency pulled all of its 7000 series railcars after Oct. 12's partial derailment on the Blue Line, which happened near the Arlington Cemetery station.
The eight-car test trains are stopping at stations but not carrying passengers, Metro said.
It’s part of the plan to submit a new testing plan to safety groups, which are closely watching the tests.
Wheel issues were discovered with the 7000 series trains after that Blue Line derailment.
Nearly 200 riders sat on the dark train and then walked through a tunnel the equivalent of about six football fields to get to safety. Some riders reported smoke on the train and made panicked calls to family members to tell them they loved them, fearing the worst. One person was taken to a hospital.
Metro had known for years there were significant issues with parts of the wheels on the 7000 series railcars – yet a permanent fix was never made. If the testing goes well, the trains should eventually return to service.
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