Preliminary Summary from Rail Transit OPS Group on WMATA Red Line Train 101 Pull Apart at Twinbrook 

On Monday, December 12, 2016 at about 9:00AM Eastern Standard Time, Washington Metropolitan Area Transit Authority (WMATA) Red Line Train 101 (RD101) operating in revenue passenger service to Shady Grove suffered an uncommanded pull apart, or uncoupling between the second and third cars of the eight car consist at chain marker A2 702+00 while departing the Twinbrook station.

Upon separation, the two sections immediately went into emergency braking due to the loss of air pressure in the braking system, which resulted in rail cars 7219 and 7135 coming to rest approximately forty feet apart. The trailing six cars were still partly on the platform at Twinbrook and as such, passengers were able to exit to the platform.

There were approximately four passengers aboard the two rail cars–7134 and 7135–that separated from the rest of the consist. Three passengers were evacuated to the roadway with the assistance of a railcar maintenance employee, and the fourth passenger was transported to the Rockville station aboard the two cars due to difficulties in being able to exit the car to the roadway.

Initial review of photography appears to indicate that third rail power to at least the lead pair of cars (7134 and 7135) remained energized throughout the incident.

There were no reported injuries and damage appears to be very minimal. The investigation will be handled by WMATA to determine the factors that resulted in the pull apart.


Rail Transit OPS Group is an independent, publicly-funded group that monitors rail transit operations, performance, and safety procedures to proactively address potential issues. Like us on Facebook and follow us on Twitter.