NTSB: Wheels on derailed DC metro Blue Line train out of alignment, safety alerts issued

ARLINGTON, Va. (7News) — The National Transportation Safety Board released a report Wednesday on their investigation into the Oct. 12 Blue Line DC metro derailment. In the report, the NTSB says the train actually derailed a total of three times while it looped along the Blue Line.

A review of data shows, one of the 7200 car's wheelsets derailed and rerailed around 3:23 p.m. between Arlington Cemetery and Rosslyn while moving through a pair of switches. As the train moved to Largo Town Center, the same wheelset derailed and rerailed at 4:13 p.m. while moving through switches.

An onboard event recorder revealed that the train was traveling at 33 mph when it derailed for the third time around 4:51 p.m. between Rosslyn and Arlington Cemetery stations. Of the 187 passengers, one person was taken to an area hospital for treatment.

RELATED | Metro train derailed at least 3 times before being pulled out of service: NTSB

The NTSB said the train left the Rosslyn station when the wheelset on the fourth car derailed. The train traveled another 1,800 feet before stopping in the tunnel. The cars remained upright. The train operator, initially unaware of the derailment, though there was a stuck brake and reported it to rail operations. The rail controller told the train operator to move the train, but it wouldn't move. When a Washington Metropolitan Area Transit Authority supervisor arrived it was determined the lead axle derailed and power to the third rail was disconnected at 5:03 p.m.

Arlington County Fire Department and WMATA began to evacuate the passengers around 6:20 p.m. The derailment damage is estimated at $715,000.

NTSB investigators inspected the track and equipment, reviewed signal and train control data logs, reviewed station video and data on recorders and interviewed people. They determined the final derail was in the frog of a turnout about 166 feet south of the Rosslyn station.

They learned the wheels were well out of alignment. Wheels more than 1/16 of an inch further apart than they should be are supposed to fail inspection. Wheels on the derailed train had moved 2 inches.

Broken sections of the brake discs were found at the crossover location north of the Arlington Cemetery station and at the turnout near the Largo Town Center station.

SEE ALSO | Initial testing of weighted 7000 series trains complete, Metro officials say

The Washington Metrorail Safety Commission pulled the 748 7000 series railcars from service on Oct. 17 stating, "The prevalence of this defect throughout the 7000 Series railcar fleet is unknown and an inspection interval that is adequate to detect this defect before a safety event occurs has not been determined."

READ MORE | Continued testing of 7000-series cars extends reduced Metrorail service through year's end

WMATA announced that customers can expect continued levels of reduced service to continue through Dec. 31, 2021.

The NTSB is continuing its investigation.

In their report, officials said, " future investigative activities will focus on failure analysis of the subject wheelsets, evaluation of the response from rail traffic controllers, internal and external oversight of the WMATA system, and identification of similar wheelset issues on passenger rail cars."