The last Blue Line train to Largo services Metro Center before being removed from service on Sunday, October 17. Image by the author.

Metro announced late Sunday that the majority of its rail fleet was being removed from service and trains beginning Monday would run only every 30 minutes. The National Transportation Safety Board (NTSB-led) investigation into last week’s Blue Line derailment outside Rosslyn discovered issues with the axles that the cars run on, potentially affecting the entire car series.

Metro says the cars are being removed “out of an abundance of caution” while the NTSB investigates.

The NTSB has been leading an investigation since Tuesday to figure out why a Blue Line train derailed outside Rosslyn during afternoon rush hour. Metro is one of several groups invited to participate in the NTSB’s investigation, as well as the Washington Metrorail Safety Commission (WMSC), the independent body which oversees the safety processes of the rail system, the Federal Transit Administration and the Amalgamated Transit Union. No fatalities or injuries were reported during the derailment, although one person was later taken to a hospital with “issues related to anxiety.”

Wheel width issue was known since 2017

At a press conference Monday, Jennifer Homendy, NTSB Chairperson, said the Blue Line train derailed not once, but three times on October 12: first at Arlington Cemetery, then Largo, and finally at Rosslyn. At Arlington Cemetery and Largo, the train appears to have re-railed itself as it crossed through the switches that allow trains to cross from one track to the other, but the third derailment outside Rosslyn was final. Pieces of the train’s brake disc were found both at Largo and also outside Arlington Cemetery during the investigation.

Metro reported to the NTSB that it had been working with Kawasaki, the 7000-series railcar manufacturer, to resolve an issue with its wheel/axle assemblies, since 2017. The defect allowed the wheels on the train axles to come out of place, and on 31 occasions between 2017 and 2021 had failed inspection measurements by being too wide, and the rate of failures had been increasing from 2 in 2017 to 18 in 2021. Another 21 inspection failures were discovered on the 7000-series fleet during inspections conducted after the NTSB investigation began.

The 31 test failures prior to the derailment were found during routine 90-day railcar inspections, according to Homendy. While they didn’t result in significant derailments like the one now being investigated, the potential could have been there to cause a potentially “catastrophic event.” The car which derailed was last inspected on July 29, and was scheduled to be inspected again on October 27.

Homendy said the NTSB was concerned about the preliminary issue findings, and said the agency might end up issuing an urgent recommendation to other transit agencies who also purchased cars from Kawasaki. She noted those other agencies should check their wheel gauge widths, as well as the components, could have a shared issue.

The 7000-series railcars are the agency’s newest, arriving between 2014 and 2020, and make up 60% of the agency’s 1200-car fleet. The cars were responsible for delivering 83% of the service Metro ran during its last fiscal year. The cars have boasted higher reliability numbers than the other series, running almost 56,000 miles between breakdowns compared to 9,000, 12,000, and 13,000 miles of the 2000, 3000, and 6000-series trains, respectively.

The problem of pulling the 7000-series trains from service is compounded by an earlier decision the agency made when the 6000-series trains, which make up 15% of the fleet, were removed from service last year after two trains carrying passengers pulled apart unexpectedly on the Red Line. 16 of those 180 6000-series cars have been put back into service after safety inspections, but it’s nowhere enough to what the agency needs to run full service.

No timeline on when the cars might be back in service

The 7000-series cars were pulled from service, according to the WMSC’s order direction as such, because the axle of the car that derailed last week was “out of compliance” with the technical specifications of the railcar series. The compliance defect was also found on other cars in the 7000-series fleet.

In order to return 7000-series cars to service, the WMSC ordered Metro to assess the cause and come up with a plan to ensure that the detection and prevention of the issue can occur to prevent it from becoming serious and causing another derailment. If approved, Metro would then be able to execute a plan to put the cars back into service.

Once the plan is in place, the railcars would likely be phased back in, similar to the slow reintroduction of the 6000-series cars. This could allow service delays to diminish as more cars come back as inspections are performed. But that will take time.

In the meantime, Metro on Sunday recommended riders look into alternate ways to get around and suggested Metrobus for those taking routes served by a convenient bus. The agency implemented a new “frequent service” bus network in July, with a set of routes running either 12 or 20-minute service between 7 am and 9 pm.

Stephen Repetski is a Virginia native and has lived in the Fairfax area for over 20 years. He has a BS in Applied Networking and Systems Administration from Rochester Institute of Technology and works in Information Technology. Learning about, discussing, and analyzing transit (especially planes and trains) is a hobby he enjoys.