Eight of the previously recalled 7000-series subway cars were back on DC subway tracks Thursday, according to the Washington Metropolitan Transit Authority.
The decision to return the 7000 series trains to regular service comes after a federal investigation into a subway derailment near Arlington National Cemetery in October 2021 found a wheel defect in some of the trains.
As a result, all 7000 series cars were removed from service on all DC, Metro lines, eliminating almost 60% of Metro’s fleet.
In recent months, the old 6000 series trains have taken over; although passengers endured longer wait times due to the lack of trains.
Metro, meanwhile, has increased inspector training in an effort to prevent further derailments.
DC Metro announced plans to release all eight cars on Wednesday.
The 7000 series trains run on the Green Line, which runs from Prince George’s County, MD to Greenbelt, MD, and on the Yellow Line, which runs from Alexandria, VA to Fort Totten, in Maryland. Metro says it has done extensive testing over the past month to make adding the 7000 series trains possible.
The introduction of the trains on Thursday is the first step in a three-phase process that will see more 7000 series trains added throughout the summer.
Metro will regularly inspect newly added trains under the approval of the Washington Metrorail Safety Commission.
Trains will also be monitored using an automated process known as the Automated Wayside Inspection System to eventually monitor wheel measurements across the fleet, pending WMSC approval. .
Metro plans to increase the availability of 7000-series trains on the Blue, Silver and Orange lines in July if inspectors see positive results.