Metro has a plan to fix the wheels that it says would return the 7000-series train cars to normal service, which the transit agency has been gradually adding back into operation following a derailment more than a year ago.
The plan will include changes to the way the wheels are assembled or pressed to the rail cars, and it’s based on data released by the National Transportation Safety Board, which opened a docket of its ongoing investigation of the derailment that happened on Oct. 12, 2021.
The repairs will take about three years and cost approximately $55 million.
While the NTSB has not yet identified a probable cause for what happened, Metro engineers agreed with the board’s independent reports that an “increase to the fit and press tonnage used to mount rail wheels onto axles is required” for the 7000-series, a Metro news release said.
“The process of changing all 5,984 wheels on 2,992 axles for 748 railcars may take a couple of years to complete,” Brian Dwyer, chief operations officer for Metro, said. That’s about 20 cars a month. The 7000-series cars make up 60% of Metro’s fleet.
After months of planning, Metro added some 7000-series trains back on the tracks last summer but paused the return to deal with a “data backlog” problem related to inspections.
The latest phase of the transit agency’s plan to put more of the 7000 series back in service started in January, with a plan to measure the wheels every seven days instead of every four.
“We will take the time needed to get this right because every single rail car must undergo a rigorous process to be ready to serve our customers and support our employees,” Metro safety chief Theresa Impastato said in a news release.
The NTSB’s preliminary report released in December 2021 revealed that the wheelset problem that causes wheels on the 7000 series cars to move outward on the axle was a major factor in the derailment. The Washington Metrorail Safety Commission, the transit agency’s watchdog, said the issue was wider spread and went back further than previously known — as far back as 2017.
NTSB will issue its final report at a later date that will include analysis, findings, recommendations and a probable cause of the derailment. In the meantime, the investigation progress and documents are available on the NTSB website.