An equipment failure and a computer glitch caused headaches for Muni subway passengers during the Thursday morning commute rush hour.
Delays in the subway began a 5:09 a.m., when the subway experienced an equipment failure past the Embarcadero Station where the J-Church, L-Taraval and M-Ocean View switchback from the inbound and outbound direction,
The delay reduced the number of the trains that were able to turn around, which caused congestion inside the subway tunnel between Van Ness and Embarcadero stations.
Then, shortly after 9 a.m., Muni Metro experienced a computer failure with its Automatic Train Control System (ACTS), which control trains inside the subway. Trains were operated in manual mode for the duration of the delay with fewer trains that normal entering the subway.
While transit officials said it took five minutes to restart the computer, it was not until 10:10 a.m. that the computer system reestablished communications with the 40 trains already in the subway.
This was the second time in two weeks that a computer failure occurred causing trains inside the subway to lose communications with the ACTS. The first incident happened on Feb. 14.
Last week, SFMTA’s Acting Director of Transit Julie Kirschbaum explained to the SFMTA Board of Directors that the Feb. 14 incident was an “extremely, rare situation” where all three computers that control the ATCS failed at the same.
Transit officials said they are working with Thales, the manufacturer of the ATCS, to find the cause of the problem.
Twitter user @GregJhng took photos of what it looked like at West Portal station with Muni passengers waiting for shuttle buses.