Metro said the misrouting was caused by signal problems and that it has taken proper “corrective actions.”
“There was no safety issue,” the agency said in a statement.
The misdirection mishaps followed another operations head-scratcher; a Silver Line train traveling in the McLean area Saturday morning decoupled. The eight-car train separated into segments of five and three cars. The incident prompted the inspections of all the agency’s 5000- and 6000-series rail cars in an effort to prevent a recurrence.
No injuries were reported and riders continued their trip on another train. The agency said it is investigating the cause of the decoupling.
Meanwhile, Metro said earlier this month that it will spend the next year rewiring all of its 7000-series rail cars after internal inspections discovered wire crimping defects that were not found during manufacturing.
In Tuesday’s incident, while it was clear to riders that the train was going the wrong direction, Metro told passengers to expect delays on the Blue Line for what it called a “train malfunction” at Rosslyn.
The Blue Line train, bound for Franconia-Springfield, took the wrong route out of Rosslyn, and ended up at the Court House station, according to riders and scanner reports.
A worker could be heard over Metro’s radio identifying what was supposed to be a Blue Line train en route to Franconia-Springfield. “However, instead of keeping on in the direction of Franconia the train operator went toward Vienna,” the worker said.
One rider tweeted that the train switched its designation to Silver Line after passing Rosslyn. At Court House, the rider said, passengers were told to take the train back to Rosslyn where they could catch the Blue Line.
The Blue, Orange and Silver lines converge through downtown Washington and the rest of the system’s core before splitting into two segments at Rosslyn — Orange and Silver going west and Blue going south, via Arlington Cemetery, to Franconia-Springfield.
In Monday’s incident, a Wiehle-Reston-bound Silver Line train began heading toward Franconia-Springfield. Riders were offloaded at the Arlington Cemetery station, the agency said. Customers were delayed for about eight minutes, Metro said.
Metro spokeswoman Sherri Ly said the same signal issue was responsible for both incidents.
She said the agency was working on a fix for the problem Tuesday afternoon. Metro trains change tracks at points called crossovers, where track signals dictate the movement of switches in joint mechanisms known as “interlockings.”
The Federal Transit Administration, which has safety oversight authority over Metro, said it was aware that trains were being misrouted and that it planned to monitor the agency’s response.
“Metro is working to address the signal issue and has procedures in place to ensure the safe movement of trains,” Ly said.