
Difficulties installing advanced technology into the aging Green Line fleet have delayed the anticipated completion date for the much-needed train collision prevention equipment by 18 months.
MBTA Capital Transformation Chief Angel Peña said that the manufacturer Stadler Rail chose to delay the end date for the final installation of the Green Line Train Protection System from December 2023 to June 2025, after a review of the project made after receiving the supplier of the T project, BBR.
The decision came in late 2022, weeks before the National Transportation Safety Board concluded in its final report that the July 30, 2021 collision between two Green Line trains could have been prevented if the train’s collision prevention system had been in place. The crash killed 27 people and caused both trains to derail.
“Aside from (the Green Line Train Protection System) being a complex system on its own, incorporating this technology into our legacy fleet adds another layer of complexity to the integration,” Peña said at Thursday’s Board of Directors meeting.
“Think for a moment like trying to incorporate the self-driving features of a newer electric car with a Volvo built in the late 1980s. That’s what we’re dealing with now.”
The majority of the MBTA’s Green Line fleet consists of 103 Type 7 and 87 Type 8 cars, which were in service between 1986 and 2007.
The Green Line Train Protection System has been installed on 102 new Type 10 “supercars,” which will replace older trains when they begin arriving in the spring of 2027, at a required rate of two cars per month, Peña said.
All the cars from the $811 million investment are scheduled to be delivered by the spring of 2031, and will operate with 24 Type 9 cars, Peña said.
GLTPS is similar to positive train control in Commuter Rail, according to Peña. It combines vehicles and wayside equipment, he said, to enter speed enforcement, add red light signal protection, and will trigger automatic brakes if the operator fails to react to potential hazards, preventing train-on-train collisions.
These devices were recommended by the NTSB in 2009 following another Green Line collision that he said could have been prevented a year earlier, had a positive train control system been in place. In that instance, 68 people were injured.
But GLTPS has only been under construction at the MBTA since 2020, when the contract was awarded for the $212 million project.
To mitigate the potential risk of an 18-month delay, Peña said the MBTA is working with “system integrators” to identify creative options to safely implement various GLTPS features, including collision avoidance and speed enforcement, by January 2024, as part of a branch-by-branch approach. – branch
“This rollout strategy will address the biggest safety issues of train-to-train collisions and speeding in the near term,” said Peña. “We believe that addressing these two items will add safety value to the entire Green Line.”
Full coverage of the new system will occur in June 2025, when all GLTPS features are expected to be implemented along the light rail line, Peña said.
Older Green Line trains also make it more difficult for the MBTA to provide speed enforcement on the Green Line, according to Interim General Manager Jeffrey Gonneville.
Overspeeding on the Green Line was identified as a major problem in the MBTA Public Utilities Department’s annual oversight report, and was found to be a contributing factor in the July 30, 2021 collision.
Nine stationary speed signs are located along the Green Line; GPS data, which sends automatic alerts to lane supervisors; and daily in-person audits flag if a speed violation occurs, but this must be confirmed through data downloaded from the train, said Patrick Richmond, acting assistant general manager of rail operations.
When speeding was detected, the train was taken out of service and taken to the Riverside maintenance facility for data download verification, Richmond said.
The problem, says Gonneville, is that the Type 7 car doesn’t have a data recorder. Newer Type 8 cars have this system, but the technology is said to be from the 1990s, and not as “advanced” as today’s vehicles, such as the CRRC-built Orange and Red Line cars.
“And that’s what our engineers have to go back and basically piece together where and when this incident happened,” Gonneville said. “It’s a very timely process to do that.”
There were three confirmed cases of speeding on the Green Line in December. Two took place in the new Medford branch, and the third was on Beacon Street in Coolidge Corner in Brookline. Two employees were suspended and received retraining, Richmond said.