The MBTA has pulled all of its new Orange Line and Red Line trains out of service once again after one of the trains had braking problems Thursday at the Wellington station in Medford, Massachusetts.
MBTA officials said the issue, which disabled the train, never put riders or employees at risk and that the move was a proactive step to troubleshoot the problem.
T officials said they decided to take the new trains offline "out of an abundance of caution" while inspectors probe the newest additions to the fleet, which have faced multiple hiccups since they first launched nearly three years ago.
Orange Line service continues with the older train models, but riders may see slightly longer waits at stations.
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An MBTA spokesperson said 64 new Orange Line cars and six new Red Line cars manufactured by Chinese firm CRRC were available for passenger service before the decision Thursday to pull them from the tracks. Each train features six cars. Another eight Orange Line cars and four Red Line cars have been delivered to the T, but are still being prepared to join the fleet.
The T is partway through a multi-year contract with CRRC to replace the entire Red and Orange Line fleets with brand-new trains, which is set to be complete in April 2023 for the Orange Line and September 2024 for the Red Line following a delay.
This is not the first time the MBTA has experienced issues with the new model trains. At one point they were pulled out of service after multiple trains derailed - an issue that investigators said may have had to do with the weight of the new cars.
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The decision to pull new Orange Line and Red Line trains from service Thursday also comes as the MBTA faces heightened scrutiny from federal regulators. The Federal Transit Administration is conducting a safety management inspection of the T after top officials in Washington warned they are "extremely concerned with the ongoing safety issues" at the agency.